VoL 26, No. 1, 1995 Volume 26, Number 1, 1995 Sixteenth Annual Report of the California Bird Records Committee Matthew T. Heindel and Kimball L. Garrett 1 Greater Sandhill Crane Nesting and Production in Northeastern California, 1988 Carroll D. Littlefield 34 First Record of the Marbled Murrelet and Third Record of the Ancient Murrelet for Mexico Richard A. Erickson, Robert A. Hamilton, Steve N. G. Howell, Peter Pyle, and Michael A. Patten 39 NOTES Incubation and Brood Rearing By a Wild Male Mountain Quail David J. Delehanty 46 First United States Nesting Records of the Streak-backed Oriole Troy Corman and Gale Monson 49 Fifty Years Since Grinnell and Miller: Where is California Ornithology Headed? Michael A. Patten, Philip Unitt, Richard A. Erickson, and Kurt F. Campbell 54 Cover photo by © Renee Lynn (Davis/Lynn Photography) of Palo Alto, California: Sandhill Cranes (Grus canadensis ), Bosque del Apache National Wildlife Refuge, New Mexico, December, 1992. Western Birds solicits papers that are both useful to and understandable by amateur field ornithologists and also contribute significantly to scientific literature. The journal welcomes contributions from both professionals and amateurs. Appropriate topics include distribution, migration, status, identification, geographic variation, conservation, behavior, ecology, popula- tion dynamics, habitat requirements, the effects of pollution, and techniques for censusing, sound recording, and photographing birds in the field. Papers of general interest will be considered regardless of their geographic origin, but particularly desired are reports of studies done in or bearing on the Rocky Mountain and Pacific states and provinces, including Alaska and Hawaii, western Texas, northwestern Mexico, and the northeastern Pacific Ocean. Send manuscripts to Philip Unitt, 3411 Felton Street, San Diego, CA 92104. For matter of style consult the Suggestions to Contributors to Western Birds (8 pages available at no cost from the editor) and the Counci/ of Biology Editors Style Manual (available for $24 from the Council of Biology Editors, Inc., 9650 Rockville Pike, Bethesda, MD 20814). Reprints can be ordered at author’s expense from the Editor when proof is returned or earlier. Good photographs of rare and unusual birds, unaccompanied by an article but with caption including species, date, locality and other pertinent information, are wanted for publication in Western Birds. Submit photos and captions to Photo Editor. Also needed are black and white pen and ink drawings of western birds. Please send these, with captions, to Graphics Manager. WESTERN BIRDS Volume 26, Number 1, 1995 SIXTEENTH ANNUAL REPORT OF THE CALIFORNIA BIRD RECORDS COMMITTEE MATTHEW T. HEINDEL, 4891 Royce Road, Irvine, California 92715 KIMBALL L. GARRETT, Section of Vertebrates, Natural History Museum of Los Angeles County, 900 Exposition Blvd., Los Angeles, California 90007 In this report we review 239 records of 86 species and one hybrid recently assessed by the California Bird Records Committee (hereafter the Committee or CBRC). Of these records, 160 were accepted, yielding an acceptance rate (68%) consistent with the most recent reports (Roberson 1993, Fatten and Erickson 1994). This rate, however, is lower than in earlier reports, primarily for two reasons. First, in the recent reports, we have voted on a substantial number of historical records that have been published but not reviewed, and a higher percentage of these records has been rejected. Second, the Committee has become more conservative recently. For this report, records dating from 1956 to 1991 were reviewed, the majority being from the summer of 1990 through the spring of 1991. This report adds no species to the California list, which stands at 586 species. This “inactivity” is temporary, as the acceptance of the Alder Flycatcher ( Empidonax alnorum) will be reported in the 17th report and that of Great Frigatebird ( Fregata minor) and Fork-tailed Flycatcher (Tyrannus savanna ) in the 18th. Other potential additions to the state list under review are the Dark-rumped Petrel ( Pterodroma phaeopygia), Manx Shearwater (Puffinus), and Black-tailed Gull ( Larus crassirostris). The Band-rumped Storm-Petrel (Oceanodroma castro), on the state list by means of a single sight record, is being reconsidered. Outstanding decisions included in this report are the acceptance of California’s second record of Stejneger’s Petrel ( Pterodroma longirostris) and the rejection of prospec- tive first state records of Townsend’s Shearwater ( Puffinus auricularis ), the Band-tailed (Larus helcheri), Iceland (L. glaucoides ) and Swallow-tailed Gulls ( Creagrus furcatus), and the Oriental Turtle-Dove ( Streptopelia oriental is). All records reviewed by the CBRC are archived at the Western Founda- tion of Vertebrate Zoology, 439 Calle San Pablo, Camarillo, CA 93010. All Western Birds 26:1-33, 1995 1 CALIFORNIA BIRD RECORDS forms of documentation (written descriptions, photographs, recordings, videotapes, etc.) are housed at the foundation, where they are organized taxonomically and by CBRC record number. All are available for public review. The CBRC solicits information on all occurrences in California of species on its Review List (see Roberson 1993) and requests that documen- tation be sent to Michael A. Patten, CBRC Secretary, P. O. Box 51959, Riverside, CA 92517-2959. The format of this report closely follows that of recent reports (e.g., Patten and Erickson 1994). In general, records are listed chronologically by first date of occurrence. Included with each record is the location, county abbreviation (see below), and date span. The date span generally follows that published in American Birds; if the CBRC accepts a date span differing from that in a published source, the differing dates are italicized. Initials of the observer(s) responsible for the record, if known, are listed first, followed by a semicolon, then the initials of additional observers submitting documentation, then the CBRC record number. All records are sight records unless otherwise noted. Initials followed by a dagger (t) indicate that the observer supplied an identifiable photograph. A indicates a speci- men record, and is followed by the acronym of the institution housing the specimen and the institution’s catalog number. An asterisk (*) prior to a species’ name indicates that it is no longer on the Review List. The number in parentheses following the species’ name is the number of records accepted by the CBRC. Two asterisks (**) after this number indicate that the number of accepted records is limited to in a restricted review period or includes records accepted for statistical purposes only [see Roberson (1986) for more information]. When individual birds return to a locality after an absence (for example, in consecutive winters) or remain continuously for multiple years, their occur- rence in each subsequent year is reviewed as a new record. The Committee judges, by a majority vote, whether or not the same individuals are involved. Although the Committee does not formally resolve identification issues below the species level, comments on age, sex, or subspecies are often included. The authors of this report assume responsibility for all such comments, although they are usually based on comments by Committee members during circulation of the record. The Committee uses the following codes for California counties: ALA, Alameda; ALP, Alpine; AMA, Amador; BUT, Butte; CLV, Calaveras; COL, Colusa; CC, Contra Costa; DN, Del Norte; ED, El Dorado; FRE, Fresno; HUM, Humboldt; IMP, Imperial; INY, Inyo; KER, Kern; KIN, Kings; LAK, Lake; LAS, Lassen; LA, Los Angeles; MAD, Madera; MRN, Marin; MRP, Mariposa; MEN, Mendocino; MER, Merced; MOD, Modoc; MNO, Mono; MTV, Monterey; NAP, Napa; NEV, Nevada; ORA, Orange; PLA, Placer; PLU, Plumas; R1V, Riverside; SAC, Sacramento; SBT, San Benito; SBE, San Bernardino; SD, San Diego; SF, San Francisco; SJ, San Joaquin; SLO, San Luis Obispo; SM, San Mateo; SBA, Santa Barbara; SCL, Santa Clara; SCZ, Santa Cruz; SHA, Shasta; SIE, Sierra; SIS, Siskiyou; SOL, Solano; SON, Sonoma; STA, Stanislaus; SUT, Sutter; TEH, Tehama; TRI, Trinity; TUL, Tulare; TUO, Tuolumne; VEN, Ventura; YOL, Yolo; YUB, Yuba. 2 CALIFORNIA BIRD RECORDS Museums that have allowed Committee members access to specimens or have provided information are as follows: CAS, California Academy of Sciences, San Francisco; LACM, Natural History Museum of Los Angeles County, Los Angeles; SBCM, San Bernardino County Museum, Redlands; and SDNHM, San Diego Natural History Museum. Deborah L. Davidson and Michael A. Patten submitted photographs of and information about museum specimens. Other abbreviations used are AFB, Air Force Base; I., island; n. mi., nautical miles; NM, National Museum; NWR, National Wildlife Refuge; Pt., point; R., river; SB, State Beach; and SP, State Park. An addendum/corrigendum for the 14th report is available from its author, Don Roberson, at 282 Grove Acre Ave., Pacific Grove, CA 93950. THE ROLE OF THE CALIFORNIA BIRD RECORDS COMMITTEE In this section we explore, in part, the role of the Committee and its interaction with the birding community. All opinions and definitions are those of the authors, not those of the Committee as a whole. We ask that our readers keep the following thoughts in mind. First, the CBRC does not attempt to “prove” a record; this is beyond our means. Furthermore, our failure to accept a record does not mean the reported bird was not present. Rather, we decide collectively whether the available evidence supports the record to a certain threshold, a threshold that varies tremendously from member to member. The threshold also varies with the significance of a record. The more unexpected a record, on the basis of date and geography, the more cautious some members may be. Criteria for acceptance of a record may follow a continuum; although each member needs to believe that the identification was correct in order for him or her to vote for the record, some members may require less documentation for some species whereas other members may require the same high level for all species. In other words, some want the Committee to approximate as closely as possible what really happened, whereas others would rather reject records that are likely good if there is any question about them. Let’s use the following example to illustrate this point. Suppose 100 records are circu- lated, of which 90 are indeed valid. One member supports 92; the other supports 80. The first favors a more liberal policy, even though it resulted in the acceptance of two bad records, because it more accurately reflected what really happened. The other favors a more conservative policy, even though it resulted in the rejection of ten good records, because it ensured that all accepted records were, in fact, good. Of course, the situation is not this simple, but this example points out how differently various members approach this issue. There is no right or wrong, just ten individuals driven by various philosophies. Committee decisions can have undesired results. For example, most people feel a certain sense of frustration or anger if their record is not accepted. (“I know what I saw,” etc.). A sense of inequity is felt by some, who feel that if you are not part of the “gang, ” your description will not be given the same chances. There is, unfortunately, likely some truth to that feeling, although most Committee members are aware of the potential for that bias. Some argue that only a description should be reviewed, without 3 CALIFORNIA BIRD RECORDS regard for who the observer is. We believe, however, that the observer’s reputation and previous experience are important factors. If a person has a history of being able to correctly identify some difficult species, and has demonstrated that he or she understands variation that so often trips up even careful observers, that should weigh in favor of a record’s gaining acceptance. There remains, then, an element that is “unfair” to those who write a similar description but do not receive the benefit of such doubt. There is no easy answer, but an understanding of the process and an objective view would be of value. Let us share the message behind certain sentiments recently expressed to Committee members, a resentment that some (many, we fear) do not submit their sightings because they feel they will not be believed. If so, this is “birding’s loss,” diminishing our knowledge base to some degree. Several solutions to this problem are possible. The Committee could take a rather permissive tone and accept more records. This may please more people and stimulate more involvement. However, we fear that this “kinder, gentler” approach would not serve the scientific study of bird distribution. Another route is to work with the birding community, leading the way to a higher standard of documentation by helping birders understand what it takes to document a record sufficiently. We can do this, in part, through articles in local newsletters (e.g., The Western Tanager and The Gull), through workshops at meetings of the Western Field Ornithologists and local Audubon Society chapters, and through individual correspondence. Yet another angle is to minimize what we call the human side. It is not logical to expect that someone would care enough to write a description and submit it to the CBRC yet not care if the record was accepted. However, we are hopeful that some of this displeasure, and the correspond- ing “drop-out rate,” can be reduced. We feel, and these definitions are ours, there is a distinction between a “sighting” and a “record.” In some cases, we might feel that a species was likely seen, as reported, but do not want to embrace the sighting as an accepted “record.” Why? Referring to the previously mentioned continuum, we feel that there must be definitive documentation to ensure that when future ornithologists look back at the records we accept the errors will be as few as possible. Removing one’s ego from the process can be a difficult task but is a worthwhile goal. Heindel can provide a personal example. The Little Stint ( Calidris minuta) reported from Orange County and listed in this report under Records Not Accepted was his. Yes, he is disappointed that it was not accepted. Yes, he has likely seen more Little Stints (from years of experience in the Middle East) than any other member of the Committee. But this is a difficult identification, and the record was of an adult, then unprecedented. Even though the description was lengthy, it had its weaknesses. The Committee made a defensible decision. The process is more important than one person’s ego. Sometimes a sighting in which the observer has complete confidence fails to gain acceptance. Perhaps it is the ‘“wrong” decision, although such issues are rarely cast in black and white. But we feel strongly that withdrawing from the process solves little, and the potential knowledge that goes unreviewed lessens our ability to learn more about the fascinating subjects of avian vagrancy and range expansions. 4 CALIFORNIA BIRD RECORDS Why spend so much effort discussing this topic? We feel a need to reach out, increase communication within the birding community, and solicit your help. It is not self-serving to underscore that the Committee has done some worthwhile work. Yet it is not free of problems. Some of its internal conflicts have not been pretty, and have been waged for too long. This is a shame, but is also on the mend and does not negate the solidity of the Committee’s work. This discussion is a recognition of the complexities of the process and reflects a determination to improve it continually. Birders are hopelessly human. The Committee will always be imperfect; some of its decisions will ultimately be judged wrong. But ornithology can only gain by everyone’s working together to raise the level of documenta- tion. We are under no delusions here — we do not expect reams of descrip- tion for every Philadelphia Vireo (Vireo philadelphicus), nor do we expect to receive flowers from someone who has seen his or her record rejected. The less the CBRC is a self-serving, self-important group, the members voting on each other’s records, the better. The more inclusive it is, the more information it will generate for future use. We feel that, with your help, the process can yield improved results, which in the end will be worth the effort. RECORDS ACCEPTED YELLOW-BILLED LOON Gavia adamsii (51). An immature was at Moss Land- ing, MTY, 30 Dec 1990-17 Feb 1991 (SFB, JLD, MJL, GMcC, DR, SBT; 6-1991). This sighting fits the pattern of records for this species. The straw-colored distal half of the bill and the dark auricular spot, which contrasted with the paler head, were mentioned; both of these marks are excellent for this species. MOTTLED PETREL Pterodroma inexpectata (30). Eight were 42 n. mi. offshore due west of Klamath River, DN, 10 Dec 1990 (MF; 23-1991). This species continues to be seen offshore from November to March, although numbers may fluctuate from year to year. STEJNEGER’S PETREL Pterodroma longirostris (3). Two were well studied, with one being photographed (Figure 1) 53 n. mi. SW of Pt. Reyes, MRN, 17 Nov 1990 (MJA, SFB, BB, AD, EG, KH, CHK, THK, JMk, RNt, DRi, BR, TS, MTt, AW; 175-1990). The only previous record for California was for the same date in 1979 (71-1979); that earlier record was not accepted by the American Birding Association Checklist Committee, generating substantial controversy (see McCaskie and Roberson 1992; Kaufman 1991). Therefore, the photographs supporting these records are most welcome. In addition to the photographs, published in Am. Birds 45: 146 and 45:174, the observers compiled an impressive series of descriptions. In particular, Bailey and Hansen were very thorough, ensuring that all congeners were eliminated. For an excellent discussion of identification criteria in this complex, see Roberson and Bailey (1991) and Spear et al. (1992). ’WILSON'S STORM-PETREL Oceanites oeeanicus (12S). Up to two were on Monterey Bay, MTY, 1 1 Sep-7 Oct 1989 (RS; 95-1992). This species has proven to be quite regular in this area, and records from 1990 and later are no longer reviewed. BROWN BOOBY Sula leucogaster (36). At least eight (two adults, five subadults, and one first-year bird) were at the Salton Sea, IMP and R1V. 12 Jul-29 Sep 1990 (JLDt; SFB, NBB, MJLf, GMcC, RLMf, MAP, DR, JCWt; 99-1990). Determining the exact number of individuals was complicated. In addition to the problems caused by movements of individuals around the sea, inconsistencies among observers in 5 CAUFORNIA BIRD RECORDS terminology and ageing led to some controversy. In the end we followed the recommendations of Patten and McCaskie, who spent the most time at the sea and analyzed the situation most thoroughly. TRICOLORED HERON Egretta tricolor (4**). An adult in the Tijuana R. estuary, SD, 5-9 Aug 1990 (GMcC; JFW; 137-1990) was felt to be the same as one found nearby in the Tijuana R. valley, SD, 28 Dec 1990-11 Jan 1991 (MJL; GMcC, MAPt; 24-1991). An immature was in the Tijuana R. valley, SD, 7 Dec 1990-3 Feb 1991 (SFB; GMcC, MAP; 211-1990). One at the Whitewater R. mouth, north end of the Salton Sea, RIV, 27 Jul-24 Aug was an adult {GMcC; MAP; 110-1991). Only records from 1990 and later are under Committee review. REDDISH EGRET Egretta rufescerxs (55). An adult at the south end of San Diego Bay, SD, 2 Sep 1990-1 Jan 1991 (GMcC; MJL, MAP, GR; 135-1990, 105-1991) was the same bird with a deformed bill that had been seen annually since 1982 [see Patten and Erickson (1994) for date spans] . An immature was also on San Diego Bay, SD, 2 Sep 1990-8 Feb 1991 (GMcC; 136-1990). Another immature was found slightly to the north near Del Mar, SD, 15-24 Oct 1990 (LS; 191-1990). Yet another San Diego-area record was of an adult at San Elijo Lagoon, SD, 19 May 1991 (SWt; 100-1991). An adult in Marina del Rey, LA, 27 Apr 1990 (JRf; lb- 199 1) was only the second for Los Angeles County. YELLOW-CROWNED NIGHT-HERON N\;ctanassa violacea (14). An adult in La Jolla, SD, 18 Dec 1990-26 Feb 1991 (JLD, SFB; 46-1991) was considered to be the same individual seen here and along the adjacent coast north to San Elijo Lagoon since 25 Oct 1981; for a complete date span, see Patten and Erickson (1994). An Figure 1. This Stejneger’s Petrel (175-1990) was photographed on 17 Nov 1990, 53 n. mi. off Pt. Reyes, Marin Co. The photographs and accompanying descriptions eliminated all congeners and give California its second record of the species. Photo by Rod Norden 6 CALIFORNIA BIRD RECORDS adult was in the Tijuana R. valley, SD, 30 Sep 1990-7 Jan 1991 (GMcC, MAP; 153- 1990), and a subadult at this same location on 16 Jun 1991 stayed until at least 31 Mar 1992, by which time it had molted into adult plumage (GMcC, SEF; 88-1991). EMPEROR GOOSE Chen canagica (58). Two arrived on SE Farallon L, SF, 25 Jan 1991; one left around 1 Feb 1991, the other remained to 28 Mar 1991 (JWf; PP+, DAS; 551991). Another was found at Pt. Reyes, MRN, 11 Feb-10 Mar 1991 (PP; SFB, GMcC. JLD, MJL, JO’B; 47-1991); by an 8-2 majority, the Committee felt this individual to be different from the one that vacated the island. Another was seen at Tule Lake NWR, SIS, 25 Jan- 14 Feb 1987 (SEF, KHi, MFR; 86-1987). This bird, for which documentation was slow in coming, was agreed by the Committee to be the same bird that was at Tule Lake 19-21 Oct 1986 (Roberson 1993). We also received, through the efforts of Roberson and Patten, two older records. Two Emperor Geese were photographed near Santa Cruz, SCR, 9 Jan-19 Mar 1956 (JMit; 176-1992). This record would have remained unreviewed (see Roberson 1993) were it not for the efforts of many, including a suggestion by Laudenslayer et al. (1991); we thank Hal Michael for his help in piecing together his father’s record. Also, an immature was photographed at the Eel R. mouth, HUM, 8-20 Nov 1961 (CFYt; SWH; 112-1992). GARGANEY Anas querquedula (13). An adult male in Irvine, ORA, 12-20 Sep 1990 was the first for that county (MTH, GMcC, MAP; 132-1990). California’s first Garganeys in the desert were near Cantil, KER, 30 Sep 1990 (MTHf; JLD; 197- 1990) and at Furnace Creek Ranch, INY, 12 Oct-1 Nov 1990 (JLDf; SEFf, KLG, BHf, PEL, MJL, GMcC, KCM, MAP; 150-1990). Both of these individuals were thought to be immature males from the bold border to their speculums but relatively pale blue-gray forewing; most of the Committee felt, however, it was wiser to leave the question of the birds’ age unanswered. See Jackson (1992) for a more thorough discussion of ageing of this species. An adult male in Bolinas, MRN, 10 Oct-11 Nov 1990 (GAF, MJL, JMct, JM, SWM; 166-1990) and refound 29 Dec 1990-5 Jan 1991 (DAS; PP; 13-1991) was felt to be the same bird seen 27 Mar-30 Apr 1990 (51-1990; Patten and Erickson 1994). COMMON POCHARD Aythya ferina (1). A male at Silver Lakes, SBE, 17 Jan- 23 Feb 1991 (SFB, JLD, RAE, KLG, EGt, RAH, JML, PEL, GMcC, MAP; 7-1991; Patten 1993) was judged to be a returning bird, first seen at the same location 1 1-17 Feb 1989 (Patten and Erickson 1994). This single state record continues to raise concern as possibly pertaining to an escapee. By a 9-1 vote, the Committee concluded that its return at an “appropriate” season, coupled with the few records for Alaska (including a spring record for Homer, which might indicate a bird wintering on this side of the Pacific), outweighed the possibility of the bird’s having escaped from captivity. ’TUFTED DUCK Aythya fuligula (63). A female in Saticoy, VEN, 23 Dec 1990 (JLD; 106-1991) was judged to be the same individual present most winters since Feb 1985. Another in nearby Ventura, VEN, 19 Jan-5 Mar 1991 (PEL, DDf; 15- 1991) was judged to be different, as it lacked some white near the bill apparent on the Saticoy bird. An excellent photograph of the Ventura bird appeared in Am. Birds 45:320. This is a good example of the value of detailed descriptions. Puddingstone Res., LA, was home for what was believed to be a returning male, seen 14-17 Jan 1990 (KAR; MB, JLD, KLGt, MAP; 23-1990) and 17 Nov 1990- 30 Jan 1991 (GMcC, MAP; 171991). Two males were on Castaic Lake, LA, 28 Dec 1990-21 Jan 1991 (KLG; 101-1992). A female on Bouldin I., SJ, 15 Dec 1990 (MJL; 198-1990) was thought to be the same as one found some 10 mi. away in Stockton, SJ, three days later (DGY; 60- 1991). This is only the third record for the Central Valley, the previous two being for 7 CALIFORNIA BIRD RECORDS Stockton 22 Mar 1984 (70-1984) and San Luis Reservoir, MER, 17 Feb 1986 (173- 1986) and 21-22 Feb 1988 (209-1988). Males wintering at at least three sites in the San Francisco Bay area generated confusion over the number of individuals involved. Morlan effectively sorted out the situation as follows: A male was first found at Rodeo Lagoon, MRN, 16 Nov 1990 and was last seen there 15 Mar 1991 (SFB, JLD, GMcC, JM; 48-1991). What was likely the same bird was seen on the Sutro Bath ponds, SF, 18 Jan-16 Mar 1991; it was then seen on Lake Merced, SF, 23-30 Apr 1991 (56-1991), All of these sightings likely pertain to one returning individual, initially present 19 Nov 1988-27 Mar 1989 (257-1988) and seen again 9 Jan-26 Apr 1990 (7-1990). One observer’s seeing the bird fly from the Sutro Baths across the Golden Gate toward Rodeo Lagoon convinced the majority of the Committee that one energetic male was responsible for the various sightings. An adult male in the Mare I. area of Vallejo, SOL, 15 Mar 1990 (DAs, RL; 8- 1991) was considered the same as one located 3 mi. away, in Glen Cove, a year later, 16-22 Mar 1991 (MBG; 73-1991). Records of this species after the winter of 1991-1992 are no longer reviewed. KING EIDER Somateria spectabilis (29). A female was at Monterey harbor, MTY, 18 Mar 1991 (BAF; 521991). What was almost certainly the same bird was at Moss Landing harbor, 2 Jun-6 Sep 1991 (DR, RST; 101-1991). It was one of the few King Eiders to be seen through the summer in California. MISSISSIPPI KITE Ictinia mississippiensis (20). A first-year bird was at Oasis, MNO, 25-26 May 1990 (PR; 89-1990), The majority of the records of this species are from late spring at such desert oases. ZONE-TAILED HAWK Buteo albonotatus (31). An adult was near San Marcos, SD, 22 Dec 1990 (JO’B; 107-1991). Another adult photographed near Escondido, SD, 19 Dec 1990-12 Mar 1991 (GMcC, MAP, HWt; 26-1991) was felt to be a returning bird, seen first on 30 Dec 1989 (84-1990). An immature was at this same location 30 Jan-18 Mar 1991 (GMcC; 25-1991). This species is becoming quite routine in winter in portions of San Diego and Orange counties. GYRFALCON Falco rusticolus (6). One at Lower Klamath NWR, SIS, 23 Jan 1985 (RRHt; 198-1989) came to our attention in a most unusual way. In the May 1989 issue of MD Magazine, in an article discussing the comeback of the Peregrine Falcon ( Falco peregrin us), mixed in with a few photos of Peregrines was one of a Gyrfalcon (Figure 2), labeled as a Peregrine. Craig Roberts of Tillamook, Oregon, noticed the misidentification and alerted us. WILSON’S PLOVER Charadrius wiisonia (5). One was photographed at the mouth of the Tijuana River, near Imperial Beach, SD, 9 Apr 1991 (DP-C; DWA, AMt, REW; 97-1991). This is the earliest of the five state records, the others falling between 20 May and 29 Jun; it is also the first since 1979. AMERICAN OYSTERCATCHER Haematopus palliatus (12). One was on Santa Barbara I., SBA, 30 May 1987 (BWA; 375-1986); this record has been subsumed into the 1986 record of one at the same locality, reported by Bevier (1990). UPLAND SANDPIPER Bartramia longicauda (1 1). A juvenile was photographed near Oxnard, VEN, 15-20 Sep 1990 (RJM; DDf, KLG, BH|, PEL, GMcC, JO’B, MAP, DR; 124-1990). The cooperativeness of this bird was much appreciated, as most previous Upland Sandpipers in California remained for only a single day. HUDSONIAN GODWIT Limosa haemastica (9). California’s second was photo- graphed near Daggett, SBE, 9 May 1975 (GSt; 102-1990). A photo was published in Am. Birds 29:908, but that photo did not, in some people’s minds, eliminate the 8 CALIFORNIA BIRD RECORDS Black-tailed Godwit (L. limosa ), a potential stray to California. The Committee thanks Mike San Miguel for his work in obtaining copies of the original photos, which were conclusive, LITTLE STINT Calidris minuta (3). Most remarkable was a Little Stint in first basic plumage collected at Harper Dry Lake, SBE, 21 Nov 1988 (#SBCM 52766; 210-1990). It was clearly a small Calidris without any trace of webbing, fitting the Little Stint/Rufous-necked Stint (C. ruficollis ) species pair. Patten carefully measured the specimen on two occasions, confirming its identification as minuta. For further information on measurements and identification, see Prater et al. (1977). This species’ being found in California on this date is both exciting and disconcerting. How many others have come through (or stayed), only to be overlooked in their basic plumage, which so closely matches that of the Western Sandpiper ( Calidris mauri)? WHITE-RUMPED SANDPIPER Calidris fuscicollis (11). An adult was in Irvine, ORA, 9-13 Sep 1990 (BED, MTHt, GMcC, MAP; 131-1990). Adult White-rumped Sandpipers are very dull at this time of year; this bird was in typical basic plumage Figure 2. This picture of the Gyrfalcon at Lower Klamath Natl. Wildlife Refuge, Siskiyou Co., 23 Jan 1985 (198-1989), shows a grayish bird with a poorly defined moustache and a tail extending well beyond the primary tips, both excellent marks for this species. Photo by Richard Hansen 9 CALIFORNIA BIRD RECORDS except for a few black streaks on the flanks. This is the third fall record for California; all three are of adults. ’BUFF-BREASTED SANDPIPER Tryngites subruficollis (77). Juveniles were photographed on SE Farallon I., SF, 15-18 Aug 1990 {PPt; 144-1990) and 31 Aug 1990 (PPt; 145-1990). A juvenile was at Ft, Reyes, MRN, 1 Sep 1990 (AME; 212- 1990). A juvenile photographed at Edwards AFB, KER, 16 Sep 1990 (MTHt; 201- 1990) was the fourth recorded at this locality. One in the Tijuana R. valley, SD, 21- 25 Oct 1990 (GMcC; 161-1990) was late but overshadowed by an even later one there 17-23 Nov 1990 (GMcC; 1-1991). At the time this was the latest record for California and the entire United States, though subsequently a juvenile was photo- graphed at the same locality 4-7 Dec 1993 (Natl. Audubon Soc. Field Notes 48:248). This species has proven regular in California and poses little identification problem; records after 1991 will no longer be reviewed. LITTLE GULL Larus minutus (43). An adult was at Ravenswood, SM, 31 Mar 1991 (PJM; 86-1991). A first-winter bird was in Santa Cruz, SCZ, 23 Dec 1990-6 Feb 1991 (PELt; GMcC, MAP, KARf, SBT; 3-1991); a photograph of it appeared in Am. Birds 45:317. THICK-BILLED MURRE Uria lomvia (20). One was photographed in Monterey Bay, MTY, 26 Aug-6 Sep 1990 (MO’B; SFBf, DRt; 116-1990). The early date and worn plumage elicited considerable debate. Some felt the bird was more likely a holdover from the influx of the previous fall (Patten and Erickson 1994); in the end the Committee agreed to consider it a new arrival because of the absence of this species at this locale in the intervening months. PARAKEET AUKLET Cyclorrhynchus psittacula (36). Two were about 95 n. mi. WSW of San Nicolas I., VEN, 3 Mar 1991 (both PP; 61- and 62-1991). In his notes Pyle indicated that these birds were in a zone of water mixing on the boundary of the California Current. He saw another approximately 98 n. mi. W of San Nicolas I., VEN, 6 Mar 1991 (PP; 63-1991). Pyle, who has extensive experience with alcids, noted the bright white undertail coverts this species typically shows as it flies away from a boat. Parakeet Auklets often fly 4-5 m above the surface, enhancing this character’s visibility. RLJDDY GROUND-DOVE Columbina talpacoti (25). One was at Iron Mountain Pumping Plant, SBE, 1 Oct 1990 (DSt; 139-1991). A female was at Imperial Beach, SD, 8 Sep 1990 (GMcC, JM; 134-1990). A male was photographed at Deep Springs, INY, 26 Sep 1990 (PEL, JLDf; 169-1990), constituting the northernmost record for the state. A male photographed near Cantil, KER, 30 Sep 1990 (MTHt; JLD; 190-1990) was the first for Kern County. Determining the number of Ruddy Ground-Doves at Furnace Creek Ranch, INY, can be difficult. This species can be easily overlooked, and difficulty of sexing some individuals (Patten and Erickson 1994) leads to confusion; the Committee followed the scenario proposed by Patten: A male was present from 14 Oct to 24 Nov 1990, combining records 156-1990 and 204-1990 (KLGf; PEL, GMcC, MAP, KAR). A female was there 17-24 Nov 1990 (GMcC, MAP; 205-1990). Two birds, variously reported as males or females but best left undetermined, were present 17 Nov-23 Dec 1990 (MAP; GMcC, MP, KARt; 219-1990, 220-1990 and 109-1991). ‘BARRED OWL Strix uaria (7). One nicely sketched bird was near Crescent City, DN, 29 Oct 1989 (ADB; 35-1990). Although records of this species in California are still few, its apparent establishment in the northwestern corner of the state prompted the Committee to remove it from the Review List in 1990. BROAD-BILLED HUMMINGBIRD Cynanthus latirostris (35). A male was in Orange, ORA, 11 Feb 1991 (DRW; 68-1991). Although this species was seen 10 CALIFORNIA BIRD RECORDS regularly from 1976 to 1988 (31 records), this is, strangely, the first accepted record since March 1988. GREATER PEWEE Contopus pertinax (25). One at Peters Canyon, Tustin, ORA, 10-13 Feb 1991 (GMcC; DLD, MAPf; 20-1991) was the second recorded in Orange Co., the first being at the same site 14 years earlier. This bird undoubtedly wintered locally, fitting the well-established fall and winter pattern for this species in California. SULPHUR-BELLIED FLYCATCHER Myiodynastes luteiuentris (6). One was photographed at Goleta, SBA, 23-28 Sep 1990 (RFJt; SEF, PEL, MAP; 163- 1990); a color photo was published in Am. Birds 45:177, 1991. Many Committee members included in their comments a discussion of the identification of this bird vis- a-vis other species of Myiodynastes and related tyrannids, concluding that its plumage was diagnostic for luteiuentris. The late September date fits within the expected mid-September to early October pattern in California of this highly migra- tory neotropical species. GREAT CRESTED FLYCATCHER Myiarchus crinitus (34). One was at Pismo SB in Oceano, SLO, 7-10 Oct 1990 (KJZ; JLD; 34-1991). Like the great majority of Great Crested Flycatchers in California, this bird was along the immediate coast; all accepted records are between 4 September and 1 November. THICK-BILLED KINGBIRD Tyrannus crassirostris (8). One at Peters Canyon, Tustin, ORA, 16 Dec 1990-16 Mar 1991 was returning for its ninth consecutive winter (JWr, DLD, JLD, BH, GMcC, MAP; 21-1991). SCISSOR-TAILED FLYCATCHER Tyrannus forficatus (68). One was near Big Pine, INY, 29 Sep-13 Oct 1990 (THf, JH; SEF, PEL, GMcC, MAP; 157-1990). One was at Upper Newport Bay, ORA, 17 Mar-27 Apr 1991 (BO; JLD, MTHf, GMcC; 70-1991). One was at Lake Cuyamaca, SD, 26-28 Jun 1991 (DDG; GMcC; 89-1991). One was photographed at Furnace Creek Ranch, INY, 23 May 1991 (BHef; 99-1991). Unlike many vagrants to California, the Scissor-tailed Flycatcher occurs in a complex seasonal pattern, with records for the state in every month of the year (at least one accepted December record will be published in an upcoming CBRC report). The Big Pine bird was a fall vagrant; the Furnace Creek Ranch bird was a spring vagrant. The March record coincided with the first major wave of migrant Western Kingbirds but could also pertain to a wintering bird; the late June record is more difficult to categorize. WOOD THRUSH Hylocichla mustelina (9). One at Harbor Regional Park, Harbor City, LA, 10 Oct 1990 was accepted 9-1 (MH; BPE, BP; 148-1990). The one dissenter based his vote primarily on the brevity of the observation by all three reporting observers and the slightly early date. Four of the eight previously accepted records of this species are from late October and November. GRAY-CHEEKED THRUSH Catharu s minimus (14). One was at Pt. Loma, SD, 10-11 Sep 1990 (GMcCf, RAE; 133-1990). It was mist-netted and banded by Bunny Jones and Ginger Johnson on the first date, when McCaskie took in-hand photos. All but two of the accepted records of this species for California are from September and October; this for Pt. Loma establishes the earliest in fall by two days. The only specimen of the Gray-cheeked Thrush for California is of the widespread race C. m. alicioe (or minimus if the former is not recognized). The records with measurements (e.g, those from SE Farallon I.) conform with aliciae and eliminate the smaller and more richly colored Bicknell’s Thrush (Catharus bicknelli ), considered specifically distinct by Ouellet (1993). 11 CALIFORNIA BIRD RECORDS GRAY CATBIRD Dumetella carolinensis (52). One was photographed near the mouth of the Santa Maria R., SBA, 5 Oct 1990 (SEFt; 183-1990). One was in Costa Mesa, ORA, 19 Oct 1990 (BO; RAE, RAH; 186-1990). One was at Black Rock Fish Hatchery, 10 mi. S of Independence, INY, on 23 Oct 1990 (JH, TH; 218- 1990) . One was photographed at Pajaro Dunes and Sunset SB, SCZ, 1 Jan-9 Feb 1991 (PJM; SFB, JLD, RAE, EG, MJL, PEL, GMcC, DR, DLS, SBT, RFTt; 14- 1991) . One was in Joshua Tree woodland near Butterbredt Spring, KER, 1 Jun 1991 (MTH; 76-1991). The first three records fit a well-established fall and early- winter pattern; small numbers are also recorded in late spring, as indicated by the Kern County record. YELLOW WAGTAIL Motacilla f lava (8). One was at Crescent City, DN, 12 Sep 1986 (ADB; 134-1992). This species has a well-defined September “window” of occurrence in California; all records are for the immediate coast between 4 and 21 September. WHITE WAGTAIL Motacilla alba (2). A returning adult male was at settling ponds near Saticoy, VEN, 8 Nov 1990-9 Mar 1991 (DDet, GMcC, MJL, MAP; 188- 1990; Figure 3). From 22 Nov 1987 to 6 Mar 1988 and 16 Oct 1988 to 4 Mar 1989 it was about 2 mi. away at a different set of ponds. Because the bird was not seen at all during winter 1989-1990, some Committee members felt the one in 1990-1991 was possibly a different individual, but all agreed that the best scenario was to accept it as a returning bird. ’RED-THROATED PIPIT Anthus cervinus (73). Two were on the Oxnard Plain in Port Hueneme, VEN, 30 Sep-3 Oct 1990 (LS; JLD, RJM; 149-1990). Up to two were in the Tijuana R. valley, SD, 13-24 Oct 1990 (GMcC; 158-1990). One in Goleta, SBA, 1 Oct 1990 was identified principally by call note (JLD, PEL; 180- 1990). One was near the Santa Maria R. mouth, SBA, 6-7 Oct 1990 (PEL; 1811990). One was in fields near the Oxnard Plain in Camarillo, VEN, 7 Oct 1990 Figure 3. This adult male White Wagtail (188-1990) at the Saticoy settling ponds in Ventura Co. on 17 Nov 1990 was thought to be the same individual present nearby in the winters of 1987-1988 and 1988-89. 12 Photo by Don Desjardins CALIFORNIA BIRD RECORDS {PEL; 182-1990); this site is several miles from that for record 149-1990. One {distant photos) was on SE Farallon L, SF, 24-27 Sep 1990 (PPt; 101991). One was at Thompson Reservoir, Santa Catalina I., LA, 26 Oct 1990 (HU; 38-1991). This Eurasian species, no longer on the CBRC Review List, has a well-defined pattern of vagrancy, primarily to coastal regions, from mid-September through mid- November, with the great majority of records from late September to late October; all of the records above fit this pattern. YELLOW-THROATED VIREO Vireo flauifrons (39). One was near the east shore of Upper Newport Bay, ORA, 3 Jan 1988 (HLJ; 28-1989). The only previous midwinter record was of one in Riverside, RIV, 5 Dec 1969-19 Mar 1970 (Binford 1983). Considerable discussion centered around the question whether the bird at Upper Newport Bay was a Pine Warbler, much more likely in midwinter; these two species are confused frequently in the southeastern United States in winter (J. V. Remsen pers. comm.). One was at Panamint Springs, INY, 13-14 Oct 1990 (GMcC; KLG, KCM, MAP; 151-1990). PHILADELPHIA VIREO Vireo philadelphicus (81). One was on Pt, Loma, SD, 22-26 Sep 1990 (LSa; GMcC; 152-1990). One was near the Carmel River mouth, MTY, 6 Oct 1990 (KW; 173-1990). One was at Galileo Hill Park, KER, 19 Oct 1988 (REW; 66-1991). One was collected at Harper Dry Lake, SBE, 11 Oct 1990 (#SBCM 52732; 54-1992); this bird proved to be an immature female. One was at the Smith R. estuary, DN, 4 Sep 1990 (ADB; 135-1992). The last represents the first for Del Norte County; Mendocino County, relatively undercovered, is now the only county on the immediate coast lacking a record of this species. YELLOW-GREEN VIREO Vireo flavoviridis (29). One was in Golden Gate Park, SF, 23-26 Sep 1990 (SWM; JM, RST; 139-1990). One at Pt. Loma, SD, 7-17 Oct 1990 (GMcC, AME; 155-1990), was seen by several observers during this period, but documentation was submitted only for 7 and 14 Oct. This problem is a recurring one, and all observers are encouraged to send in descriptions, both to increase the quality of documentation of records and to fill in date spans. All but one of the California records of this species are coastal, and all fall between 8 September and 30 October. BLUE-WINGED WARBLER Vermiuora pinus (12). A singing male was photo- graphed at Huntington Central Park in Huntington Beach, ORA, 28 May 1990 (DRW; MHf; 105-1990). Of the 12 California records, seven are for May and June; this, however, is only the second spring record for the coast. BLUE-WINGED x GOLDEN-WINGED WARBLER Vermiuora pinus x chrysop- tera (3). A Brewster’s-type hybrid was captured and banded on SE Farallon I., SF, 6 Jun 1991 (PPt; 80-1991; Figures 4 and 5). GOLDEN-WINGED WARBLER Vermiuora chrysoptera (41). A male was in Moss Beach, SM, 22-24 Sep 1990 (RST; JM, BDP; 141-1990). A male was at Morongo Valley, SBE, 27 Oct 1990 (MAP; DLD; 164-1990). A male was at Lake Palmdale, LA, 21 Sep 1990 (JKA; 195-1990). A male was banded and photographed on SE Farallon I., SF, 3 Jun 1991 (PPt; 79-1991); a color photograph was published in Am. Birds 45:1179. A singing male was along Keys Creek, midway between Pala and Valley Center, SD, 22 May 1991 (EL; 91-1991). A female was in the Tijuana R. valley, SD, 15 Dec 1990 (REW; 104-1991). These records engendered considerable discussion of age criteria in this species. The Committee concluded that the males were best left unaged, except for the one on SE Farallon bird, identified in the hand as a second-year bird by the shape, wear, and faded colors of the rectrices and remiges. 13 CALIFORNIA BIRD RECORDS Figures 4 and 5. These pictures of a Brewster’s (Blue-winged x Golden-winged) Warbler (80-1991), taken on SE Farallon I. on 6 Jun 1991, are the first from California to be published in color. This is only the third record of this hybrid for California. 14 Photos by Peter Pyle CALIFORNIA BIRD RECORDS Figure 6. This Louisiana Waterthrush (78-1991) is the first for northern California. It was found on SE Farallon I. on 2 Jun 1991. Photo by Peter Pyle Figure 7. California’s fourth Brambling (196-1990) was widely seen in Santa Cruz, Santa Cruz Co. This photo was taken on 31 Dec 1990. Photo by Bob Hefter 15 CALIFORNIA BIRD RECORDS PINE WARBLER Dendroica pinus (40). A male was in Morro Bay, SLO, 20 Dec 1988-3 Feb 1989 (TME; 31-1989). A majority of Committee members felt this bird was probably not the same individual there 19 Dec 1987-29 Mar 1988 (Pyle and McCaskie 1992). A male (immature?) was in the Tijuana R. valley, SD, 17-19 Oct 1990 (GMcC; 160-1990). A female-plumaged bird was in San Diego, SD, 3-21 Mar 1991 (GMcC, MAP; 49-1991). Even though this species is an early spring migrant in eastern North America, the early March date and lengthy stay strongly suggest that the last bird wintered locally. All Pine Warblers in California have been in fall and winter except for one on 31 May 1984 at Furnace Creek Ranch, INY (Roberson 1986), a singing male 5-6 Jun 1987 at Torrey Pines SP, SD (Langham 1991), and one on 7 Apr 1984 at Clear Creek Station, LA (Bevier 1990); the last may also have wintered in the vicinity. YELLOW-THROATED WARBLER Dendroica dominica (61). One at Pismo SB, Oceano, SLO, 30 Sep-2 Oct 1990 (KJZf, MJL; 143-1990) showed the characters of the expected race albilora. GRACE’S WARBLER Dendroica graciae (26). One was in Montecito, SBA, 23 Sep 1990-25 Feb 1991 (PEL, SEF, GMcC; 1771990). From its relatively dull plumage it was a female, probably immature, and thus not a repeating wintering bird (males have wintered nearby). A female-plumaged bird was at Deer Spring, MNO, 26 Jun 1991 (WDS; 111-1991) and represents the first accepted record north of San Bernardino County, though Johnson and Garrett (1974) noted some expansion of the breeding range. WORM-EATING WARBLER Helmitheros vermivorus (58). One was banded at Palomarin, MRN, 4 May 1979 (KHt, DDeS; 24-1989). LOUISIANA WATERTHRUSH Seiurus motacilla (5). One was banded and photographed on SE Farallon I., SF, 2-3 Jun 1991 (PPt; 78-1991; Figure 6). In- hand criteria suggest that bird was in its second calendar year; though there was speculation based on its dull plumage that it might have been a female, this species cannot be sexed by plumage characters. This is the first record of this species for the thoroughly worked Farallon Islands and for anywhere in northern California. KENTUCKY WARBLER Oporornis formosus (59). One was on Pt. Loma, SD, 14-17 Sep 1990 (DWA, GMcC, MAP; 130-1990). One was in Pacific Grove, MTY, 21-29 Oct 1990 (DRf, BJW; 162-1990), the first for well-covered Monterey County. One was banded and photographed on SE Farallon I., SF, 1-3 Oct 1990 (PPt; 12-1991). Of the 12 Kentucky Warblers recorded for SE Farallon, this bird, a hatch-year male, was only the second in fall. A singing male was at Scotty’s Castle, Death Valley NM, INY, 31 May-1 Jun 1991 (JH, TH; GMcC, MAP; 71-1991). One was banded and photographed on SE Farallon I., SF, 2-4 Jun 1991 (PPt; 77-1991). One was at California City, KER, 19 Oct 1984 (JCW; MTH; 216-1992). Though this represents the first record for Kern County, 15, all but one in spring, have been accepted through 1992. MOURNING WARBLER Oporornis Philadelphia (73). One was at the Carmel R. mouth, MTY, 28 Sep 1990 (GWL; 142-1990). One was at Gaviota SB, SBA, 13 Sep 1990 (PEL; SEF; 176-1990). One was along Carpinteria Creek, SBA, 23 Sep 1990 (PEL; 178-1990). One was banded and photographed on SE Farallon I., SF, 30 Sep 1990 (AB, PPt; 1 1-1991). One was at Mad River County Park, HUM, 5-8 Sep 1990 (GSL, LPL; BBA, SWH; 64-1991). These fall records fit a well-established pattern. A female was banded and photographed on SE Farallon I. 7-11 Jun 1991 (PPt; 81-1991); though this is the 37th record for the island, it is only the first of a female in spring, 16 CALIFORNIA BIRD RECORDS CONNECTICUT WARBLER Oporornis agilis (61). One was on Ft. Loma, SD, 14-15 Sep 1990 (GMcC; 129-1990). One was at Stovepipe Wells, Death Valley NM, INY, 22 Sep 1990 (MAP, KAR; 167-1990). One was at Scotty’s Castle, Death Valley NM, INY, 22-27 Sep 1990 (KAR; JLDt, JH, TH, MAP; 168-1990). One was in Goleta, SBA, 28-30 Sep 1990 (SEF, PEL; 179-1990). One was 4 mi. S of Half Moon Bay, SM, 22 Sep 1990 (RST; 1871990). One was banded, measured, and photographed on SE Farallon I., SF, 18 Sep 1990 (RPHt; 9-1991). These fall records fit a well-established pattern for this species in California; all but five state records are from 1 September to 22 October, and over half of these are for the latter half of September. The two for Death Valley are only the second and third records for interior California. SCARLET TANAGER Piranga olivacea (75). One male was on Pt. Loma, SD, 14-16 Oct 1990 (GMcC, JLD; 159-1990). One male at Mojave, KER, 19 Oct 1990 (MTH, JCWf ; 202-1990) was the first for Kern County. One was in Costa Mesa, ORA, 12 Nov 1990 (RAE, RAH; 45-1991); the bird was possibly present several days earlier, when briefly seen by RAH. PYRRHULOXIA Cardinalis sinuatus (12). A male was on San Miguel I., SBA, 19-23 Jul 1990 (DAGf; 140-1990; photo published in Am. Birds 44:1188). This represents the first record for the Channel Islands and is an amazing example of vagrancy. The question of possible captive origin has been raised with all coastal sightings, but the consensus of the Committee was that natural occurrence was more likely on this remote island. PAINTED BUNTING Passerina ciris (36). One was in Cambria, SLO, 18-19 Sep 1988 (JHa, GPS, KHa; 235-1988). One was in Goleta, SBA, 18 Sep 1989 (ABi; SEF, PEL; 157-1989). One was at Furnace Creek Ranch, INY, 25 Sep 1990 (PEL, JLD; 170-1990). One was near Cantil, KER, 6 Oct 1990 (RAE; MTHt; 203-1990). The Committee engaged in its usual discussion of natural occurrence, weighing such factors as coastal vs. interior localities, spring vs. fall dates, adult male vs. other plumages, and urban vs. rural habitats. Many records also generated discussion about ageing and sexing. Most Committee members were conservative with ageing female- plumaged birds, given the complexity of molt in Passerina buntings (see Thompson 1991). LE CONTE’S SPARROW Ammodramus lecontei (19). One was at the Santa Clara R. estuary, VEN, 23-24 Sep 1990 (RJM, BHet; 185-1990). The submitted descriptions were not convincing in themselves, but the photographs were identifi- able, and suggested that the bird was an immature, retaining some juvenal plumage. SNOW BUNTING Plectrophenax nivalis (44). Two were at Lower Klamath NWR, SIS, 30 Oct-11 Nov 1989 (JO, BEDe, RE; 124-1989). Although there was no question about the identification of these birds, resolving the date span proved more difficult. Two were at Bear River Ridge near Scotia, HUM, 2-10 Nov 1990 (GH; BBA, GSL; 65-1991). One was at Tule Lake NWR, MOD, 27 Dec 1990 (MFR; 108-1991). One was at Lower Klamath NWR, SIS, 2 Dec 1990 (CYt; 180-1991). COMMON GRACKLE Quiscalus quiscula (25). One was at Oasis, MNO, 24 May 1987 (CDB; SFB, SEF, JML, PEL, MJL, CAM, GMcC, DR; 140-1987). The record generated considerable debate regarding the reported presence of a second bird. Even though the first bird was accepted on the first circulation, the Committee took three additional rounds discussing the second; on the final round the vote was 6-4 in favor of accepting two birds, not enough for approval. Another was at Fish Springs, south of Big Pine, INY, 12 Dec 1990 (JH, THf; 50-1991); this represents the latest fall record for the interior. A male was at the Smith R. mouth, DN, 24 Sep 1990 (ADB; 235-1992), the third record for Del Norte County. 17 CALIFORNIA BIRD RECORDS BRAMBLING Fringilla montifringilla (4). One was in a residential area in Santa Cruz, SCZ, 15 Dec 1990-16 Feb 1991 (DV, PR; SFB, PDeB, JLD, TF, BHet, CK, PELf, ELt, MJL, GMcC, JM, JO, MAP, DR, DLS, SBT; 196-1990; Figure 7). This widely seen bird was recorded on videotape, broadcast on a local television news program! It represents the fourth record for California, all for late fall and winter. RECORDS NOT ACCEPTED, IDENTIFICATION QUESTIONABLE YELLOW-BILLED LOON Gauia adamsii. An interesting rerort was of one at Eureka, HUM, 16 Apr-1 May 1988 (202-1988). Distant photos suggested this species, giving a sense of a pale bill, but the description specified a pale gray culmen. The record circulated four rounds with the final vote evenly split, 5-5. One in Abbott’s Lagoon, MRN, 20 Aug 1990 (192-1990) failed to gain any votes on the first round. The bird was said to have a pale gray bill, which with the unusual date caused considerable concern. WEDGE-TAILED SHEARWATER Puffinus pacificus. An intriguing description was received of one along the shore at Pt. Reyes, MRN, 16 Dec 1989 (205-1989). Another, from an experienced pelagic observer, was of one seen 60 n. mi. off San Nicolas I., VEN, 16 Jan 1991 (67-1991). The first was said to have glided on bowed wings, a feature good for this species. However, the descriptions of the tail length and shape, as well as wingbeats, differed greatly between observers. The record failed 3- 7 on the second round. The observation off of San Nicolas I. was too brief and lacked details on bill color and tail length and shape. California still has only two records of this species: off Pt. Pinos, MTY, 31 Aug 1986 (Stallcup et al. 1988) and the remarkable stray at the north end of the Salton Sea, RIV, 31 Jul 1988 (McCaskie and Webster 1990). TOWNSEND’S SHEARWATER Puffinus auricularis. One was reported near Cordell Banks, west of Pt. Reyes, MRN, 28 Oct 1990 (165-1990). This would have been a first record for California and the United States but was rejected 3-7 on the third round. All Committee members were impressed with the level of documenta- tion, in both the thoroughness of the descriptions and the number of submitting observers (19). Everyone agreed that an interesting small black-and-white shearwater was seen. Furthermore, the bird showed white “saddles” on the sides of the rump, a feature of this species. The undertail coverts were thought to be dark, but there was not a consensus on this point. As is so typical with pelagics, the observation was rather brief, in this case less than a minute. Questions about the undertail covert color and no black being noted in the axillaries (a mark Townsend’s should show) led the majority to reject. Some members wondered whether the Manx Shearwater (P. puffinus) was eliminated, which might find these cold waters more attractive. At least one of the observers now believes this record does pertain to a Manx. Manx shows some degree of white “saddles" (Howell et al. 1994). One or more possible Manx shearwaters photographed off central California in fall 1993 are currently circulating through the Committee. Pyle has noted an anomalous Black-vented Shearwater (P. opisthomelas) showing white saddles. It is apparent that we still have much to learn here about the occurrence of small shearwaters off of our coast. BAND-RUMPED STORM-PETREL Oceanodroma castro. A report of nine seen 115-175 n. mi. SW of San Nicolas I., VEN, 20 Jul 1989 (107-1989) has raised again the issue of the identification of this difficult species. The observer, one of our most experienced with pelagics, shares the opinion of the majority of Committee members that we are still learning about the identification of Band-rumped and Leach’s (O. leucorhoa) Storm-Petrels and that this record should not be accepted at this time. Leach’s may vary substantially in the amount of white it can show wrapping 18 CALIFORNIA BIRD RECORDS RECORDS NOT ACCEPTED, identification questionable, Cont. around the base of the tail and in flight characteristics. The depth of the tail fork seems to be a reliable measurement but can be exceedingly difficult to judge accurately in the field. Some feel that the Band-rumped is likely in our waters but that photographic or specimen evidence may be necessary to prove this. At a minimum our level of knowledge must be increased. One 15 n. mi. W of San Nicolas I., VEN, 25 Jul 1989 (22-1991) was unanimously rejected, as the description was very brief. The true status of this species in our waters is causing substantial debate within the Committee. There is one accepted record: 12 Sep 1970 off San Diego, SD (McCaskie 1990), Because of the issues discussed above, the Committee voted at its 1994 annual meeting to recirculate the 1970 record for further evaluation. MASKED BOOBY Sula dactylatra. An adult was reported from San Elijo Lagoon, SD, 14 Nov 1987 (57-1988). It was apparent that a white booby with a black tail was seen. However, many members were concerned about the face’s being described as “vivid blue,” as the bare facial skin of the Masked Booby should be black, or subtly dark blue. The Red-footed Booby (S. sula ) was not eliminated in the opinion of some. The latter may have bright blue at the base of the bill. The record received only two accept votes after three rounds. BLUE-FOOTED BOOBY Sula nebouxii. A report of an unsalvaged dead bird at the north end of the Salton Sea, RIV, 11 Sep 1973 (86-1990), was rejected 4-6 on the third round. No notes were taken at the time, and the recollection was under- standably incomplete. Although this species has occurred a number of times at this locale, it usually does so only during “invasion” years. No other reports of this species were received in 1973. TRICOLORED HERON Egretta tricolor. A most unusual heron that may well have been an aberrant Tricolored was seen near Red Hill at the south end of the Salton Sea, IMP, 11 Aug 1990 (29-1991). Distant photos showed a blue-and-white heron with the general pattern of this species in a plowed field. Marks causing concern included tertials with white fringes, patches of white on the scapulars and wing coverts, and traces of bluish on the thighs. The scapulars may have been bleached-out breeding plumes, and the bluish thighs might be matched by a photo in Farrand (1983). However, the tertial pattern caused concern, and some felt the overall coloration looked too pale, more like that of a Little Blue Heron (E. caerulea ), engendering talk of hybridization. The bird’s being in a field, abnormal haunts for a Tricolored Heron, was also a source of concern. Although the record was rejected on the second round, we hope that this lengthy explanation accomplishes a couple of objectives. First, if the bird was not a Tricolored Heron, it was something even more significant. Second, thorough, honest write-ups like this one can greatly increase our knowledge, in turn helping the evaluation of future records. REDDISH EGRET Egretta rufescens. One was reported at the north end of the Salton Sea, RIV, 8 May 1978 (98-1992). This bird was seen by an experienced observer but was not described at the time, resulting in a reject vote by the majority. This case exemplifies the difficulty this Committee has with many older records. Records long accepted have often never been reviewed, and there is little or no documentation for many of them. Various members have suggested that we create a category for these records, as it may be unfair to demand that they stand up to today’s standards. There are still no acceptable spring records of the Reddish Egret for the interior of the State. YELLOW-CROWNED NIGHT-HERON Nyctanassa uiolacea. One at Bodega Bay, SON, 4 May 1991 (87-1991) was rejected 3-7 on the first round. Although the 19 CALIFORNIA BIRD RECORDS RECORDS NOT ACCEPTED, identification questionable, Cont. date is good for an arrival in northern California, the description was brief and incomplete. Also, one of the observers questioned whether the bird was a Great Blue Heron (Ardea herodias), a species most unlikely to be confused in this case; this, and the distance of observation, prompted the reject vote. TRUMPETER SWAN Cygnus buccinator. A silent solitary swan was reported from Sierra Valley, PLU, 18 Mar-2 Apr 1988 (111-1988). Identification of silent swans, particularly when there are no other swans for comparison, is perilous. Some of the details were interesting, but a videotape, which surfaced after the voting, was inconclusive according to the two experts who evaluated it and may have better fit the Trumpeter’s more common congener, the Tundra Swan (C. columbianus). A dead bird was identified as this species by a California Department of Fish and Game employee at Venice I. in the Sacramento-San Joaquin R. delta, SJ, 20 Jan 1989 (53-1989). Measurements were somewhat ambiguous and the specimen was not kept, so a majority rejected the record on the fourth round. Two swans reported near Stockton, SJ, 1 Jan 1991 (59-1991) were seen only in flight. They were said to have a warm pink lateral stripe on the bill; observers are cautioned that many Tundra Swans also show this character, and some lack a yellow loral patch. This is one of the most complex identification issues confronting observers without extensive experi- ence with both species. See Patten and Heindel (1994) for more information. EMPEROR GOOSE Chen canagica. One was seen in flight at Colusa NWR, COL, 8 Dec 1990 (5-1991). The observer, a Committee member at the time, urged a reject vote after spending more time with geese in the Northwest Territories, Canada. His experience revealed greater variation in blue-morph Snow Geese (C. caerulescens ) than he had previously thought. Reports of Emperor Geese should be detailed enough to exclude the possibility of other “blue” geese. *TUFTED DUCK Aythya fuligula. One in Oakland, ALA, 4 Apr 1991 (75-1991) went 4-6 on the first round. It was described as having a dark back with a “tuft” visible under some conditions. A minority of the committee felt it was a poorly described Tufted Duck but most objected because of such problems as no discussion of the bill and flank color. One at Abbott’s Lagoon, MRN, 7 Oct 1981-22 Feb 1982 (163 and 164-1987) was rejected by a split vote after four rounds. COMMON BLACK-HAWK Buteogallus anthracinus. One was reported in the Tijuana R. valley, SD, 1 May 1991 (96-1991). The description was interesting but did not specify the color of the cere or legs, both of which should be bright yellow and obvious on this species. In addition, the bird was compared to a Turkey Vulture (Cathartes aura), a species most unlikely to cause confusion. There is only one accepted record: 13 Apr 1985, Thousand Palms Oasis, RIV (Daniels et al. 1989). ZONE-TAILED HAWK Buteo albonotatus. One reported from Finney Lake, IMP, 24 Apr 1960 (93-1988) was rejected 3-7. There was little doubt that the claim was correct, but a majority were troubled by the lack of documentation prepared at the time of the sighting and therefore felt this did not meet the criteria of a “record.” RUFOUS-NECKED STINT Calidris ruficollis. One was reported (Am. Birds 45:147) from Moonglow Dairy, Moss Landing, MTY, 1-2 Sep 1990 (64-1992). This sighting provoked an extended controversy, but in the end everyone agreed the bird was a Western Sandpiper (C. mauri). We also reviewed a published record (Am. Birds 35:979) of an adult at the south end of the Salton Sea, IMP, 19 Jul 1981 (214- 1992). One of the observers is no longer convinced that an alternate-plumaged Sanderling (C. alba ) was eliminated; the description is not detailed enough to preclude this species or an adult Little Stint (C. minuta). 20 CALIFORNIA BIRD RECORDS RECORDS NOT ACCEPTED, identification questionable, Cont. LITTLE STINT Calidris minuta. An adult was reported from Upper Newport Bay, ORA, 9 Jul 1988 (156-1988). This was a single-observer sighting, and photographs were not obtained. At the time there were no records of adult Little Stints in California. Any record as unprecedented as this needs to withstand strict scrutiny, and after four rounds it was one vote short of acceptance. RUFOUS-NECKED/LITTLE STINT Calidris ruficolli$/minuta, A juvenile peep at Bolsa Chica, ORA, 16 Aug 1990 was reported as one of these two species (221- 1990). Although the bird was described as being quite bright and having a white “V” on the mantle, the Committee was concerned by its similarity to a juvenile Least Sandpiper (C. minutilla). Additionally, several parts of the bird, such as the under- parts and sides of the breast, were undescribed. Vagrants of Calidris need to be thoroughly documented, as this genus presents significant identification challenges. WHITE-RUMPED SANDPIPER Calidris fuscicollis. Two were reported from the Tijuana R. valley, SD, 30 Aug 1990 (128-1990). The descriptions were somewhat incomplete, and the simultaneity of two birds caused some concern. The descriptions seemed better for alternate-plumaged birds, with rusty edges to the upperpart feathers and a thin white “V” on the scapulars. By late August most adult White- rumped Sandpipers are remarkably dull, being mostly brownish with a few dark flank streaks. Juveniles, not yet recorded in California, are late migrants in the East, normally not seen until after mid-September. BUFF-BREASTED SANDPIPER Tryngites subruficollis. An interesting descrip- tion, possibly of this species, was received from the Santa Clara R. estuary, VEN, 9 Dec 1990 (51-1991). Perhaps a report from mid-September would have received less scrutiny, but a Buff-breasted Sandpiper on 9 December would be the latest for North America. Concerns existed about some “blotchiness” on the belly and the size comparison to a Sanderling. Only two members supported the record. COMMON BLACK-HEADED GULL Larus ridibundus. An adult was reported from the Santa Clara R. estuary, VEN, 9 Nov 1989 (202-1989), another adult was reported from Pigeon Pt., SM, 7 Apr 1990 (57-1990), and a third bird was reported from Shelter Cove, HUM, 27 Jun 1977 (19-1991). The report from Pigeon Point received the most support, though still only three accept votes. The concerns included the dark bill (the Black-headed Gull usually has a bright red bill unless it is in breeding condition, when the bill can darken), the bird’s being in basic plumage in April, and the wing’s not being seen well enough for its exact pattern to be determined. The bird at the Santa Clara R. estuary was said, among other problems, to have a light iris. BAND-TAILED GULL Larus belcheri. An adult reported from San Nicolas I., VEN, 9 Nov 1987-28 Jan 1988 (76-1988) generated considerable debate, on both identification and natural occurrence issues. The record would have been the first for California. The identification was rejected with two “identification questionable” votes. The eight members supporting the identification noted that the bird was seen on four or five occasions and that the description covered the basics of a distinctive species. The dissenters were concerned that for such a significant record the details needed to be more thorough, to ensure both that the expected race (L. b. belcheri) was involved and that hybrids were eliminated. Had this record passed on identification, it would still have failed on the question of natural occurrence. Gulls are a notoriously difficult group with respect to the natural occurrence of vagrants. They may wander great distances yet may also be kept captive. A Committee member usually makes his or her decision from individual philosophy. In the case of this species, generally restricted to the Humboldt Current 21 CALIFORNIA BIRD RECORDS RECORDS NOT ACCEPTED, identification questionable, Cont. off western South America, there has been a record for Panama. The tremendous gap between the Panama and California records, combined with this bird’s location near a major shipping channel, caused dissenters to wait for more evidence that this species could arrive under its own power. As with most controversial “natural occurrence” records, there was no evidence of captivity. LESSER BLACK-BACKED GULL Larus fuscus. Three records were rejected. One was from the Mattole R. mouth, HUM, 11 Jul 1988 (54-1991), another was from the Salton Sea, IMP, 18 Jun 1990 (174-1990), and a third was from Riverside, RIV, 24 Jan 1990 (62-1990). On the Humboldt record, the identification was not made until months after the sighting, and the description was incomplete; it received no accept votes. The Imperial report lacked enough information to support an unprecedented summer occurrence. Some felt that the California Gull (L. californi- cus ) was not adequately eliminated; that species can appear quite dark-backed. The photos of the Riverside bird as the photos clearly show a gull with a dark mantle. The Western Gull (L. occidentalis), though abundant along the coast, would be excep- tional at this location some 60 mi. inland. Committee members felt that a Lesser Black-backed should have dusky head streaking in January (the head was described as pure white). The bill shape and length was hard to determine, but some felt it favored this species. However, foot and leg color were not seen, meaning that acceptance would be based mainly on the bird’s “looking like a Western, but being too small and therefore a Lesser Black-backed.” BRIDLED/SOOTY TERN Sterna anaethetus/fuscata. A most intriguing report came from Bolsa Chica, ORA, 5 Aug 1990 (138-1990), where this bird was attracted by the colony of Elegant Terns (S. elegans). An extensive written descrip- tion pointed to an adult of one of these two species. All Committee members felt one or the other was involved with the vote split as to which better fit the description. Marks supporting the Bridled included supercilium shape and upperwing contrast (described as recalling that of a Long-tailed Jaeger, Stercorarius longicaudu s). The lack of a collar and the underwing pattern seemed best for the Sooty. There is only one California record of the Sooty Tern, from the San Diego R. mouth, SD, 27 Sep 1982 (Webster et al. 1990), none of the Bridled. Eight members felt it best not to force a name on this bird, as either species would be remarkable and neither was completely supported by the documentation. In the summer of 1993 another interesting tern, reported as either a Bridled or a Gray-backed (S. lunata), was also at Bolsa Chica (Am. Birds 47 : 1150). At this site yet again in 1994, an adult Sooty Tern was reported, currently under review by the CBRC. THICK-BILLED MURRE Uria lomvia. The two rejected records were of birds seen in flight only. One flew past SE Farallon I., SF, 28 Oct 1989 (214-1988); the other was seen from the lighthouse at Ft. Reyes National Seashore, MRN, 28 Jun 1990 (139-1989). Both observers are excellent, with extensive alcid experience. In both cases four dissenting members felt the birds, described as stockier and blacker, may have been correctly identified but that more specific details were needed. KITTLITZ’S MURRELET Brachyramphus breuirostris. Two pairs were reported near Shelter Cove, HUM, 15 Mar 1991 (53-1991). Most members felt that the variation in the amount of white in the face of the Marbled Murrelet (B. marmoratus) is not appreciated by most observers, and none was willing to support this record. Also, with only three records south of Alaska, a sighting of two pairs seems improbable. ORIENTAL TURTLE-DOVE Streptopelia orientalis. One reported from Furnace Creek Ranch, INY, 29 Oct 1988 (246-1988) would represent the first record for the 22 CALIFORNIA BIRD RECORDS RECORDS NOT ACCEPTED, identification questionable, Cont. contiguous United States. It was rejected on identification by three members, though it was seen very well by one of our best field observers, with extensive experience with this species in Asia. The supporting details, while good, were not exhaustive, and there were some minor differences between the two descriptions submitted. The dissenters centered most of their arguments on whether the documentation estab- lished such a unique record. A debate over whether this species would likely occur as a natural vagrant also ensued. There certainly has been a pattern of records in Europe (Hirschfield 1986), indicating that the species is prone to vagrancy. There are a few records from Alaska, but not all of these are necessarily unassailable. The recent record from British Columbia (Peterson 1992) was for August, earlier than a fall vagrant might be expected. For the Furnace Creek Ranch bird, the late October date seems good, and the location is a famous vagrant trap far from human population centers. In addition to the three reject votes on identification, four members decided there were too many concerns about the bird’s origin to accept it as a naturally occurring vagrant, even in the absence of evidence of captivity. RUDDY GROUND-DOVE Columbina talpacoti. A female was reported from the Tijuana R. valley, SD, 22-24 Oct 1988 (69-1989). A male was at the same location 12-20 Oct 1988 (Patten and Erickson, 1994), and two dissenters felt the description was inadequate to establish a second individual. What would have been Orange County’s first was reported from Huntington Central Park, Huntington Beach, ORA, 10 Oct 1989 (154-1989). A majority rejected this record on the third round, feeling the description needed to be more complete and that some marks better fit the Common Ground-Dove (C. passerina), a common resident in the area. A report from Ridgecrest, KER, 29 Sep 1990 (32-1991) was far too brief; it would have been the first for that county by one day. There was no description of the bill or the covert pattern, leaving many to wonder if the Common Ground-Dove was eliminated. One reported from Desert Center, RIV, 23 Nov 1990 (31-1991), had some support, but the majority felt the brief view in poor lighting was insufficient to ensure the bird was not one of the two Common Ground-Doves present at the time. RUBY-THROATED HUMMINGBIRD Archilochus colubris. An adult male was reported from Pt. Loma, SD, 19 Sep 1990 (33-1991). The vast majority of adult males have migrated south by the end of summer, and although it is conceivable that one could make it here this late in the year, it should have a flawless description. In this case there was no mention of the forked tail usually evident in this species, nor of bill length, flank color, or vocalizations. YELLOW-BELLIED FLYCATCHER Empidonax flauiuentris. One was reported at Montana de Oro SP, SLO, 27 Sep 1989 (13-1990); the observer was acknowl- edged to be experienced, excellent, and careful by all Committee members, but an uneasiness about accepting a single-observer record of a silent vagrant Empidonax seen for only about a minute ultimately led to the record’s rejection. Ironically, an accepted Yellow-bellied Flycatcher (Patten and Erickson 1994) was found the same day in Kern County. GREAT CRESTED FLYCATCHER Mpiarchus crinitus. A report of one at Pt. Loma, SD, 20 Oct 1974 (95-1988) had not been submitted earlier, and the description received was a recollection written by one of the observers 14 years later. Sightings not documented during or immediately after the fact normally have a rough ride through the CBRC. Those accepting the record cited the date and locality, which fit perfectly within the species’ established pattern of occurrence in California, and the observers’ giving convincing verbal description to at least two Committee members immediately after the sighting. The record ultimately received a 5-5 decision during a fourth circulation. 23 CALIFORNIA BIRD RECORDS RECORDS NOT ACCEPTED, identification questionable, Cont. SCISSOR-TAILED FLYCATCHER Tyrannus forficatus. One was reported in Afton Canyon, SBE, 25 May 1990 (97-1990). The fact that the bird was described as a juvenile troubled some members; no pink or salmon color was described on the bird, and the tail was said to be “relatively short.” An inordinate number of Scissor- tailed Flycatcher sightings in California are supported by brief and weak documenta- tion, perhaps because observers feel that the species is obvious enough not to require a detailed description. VEERY Catharus fuscescens. One was reported from a residential area in La Jolla, SD, 14 Sep 1990 (36-1991). Although some characteristics of this species were described, particularly the face pattern, the views were admittedly brief, and the observer indicated less than 100% certainty as to the identification. The record was unanimously rejected. WOOD THRUSH Hylocichia mustelina. One was seen and heard by several observers in Sunnybrae, HUM, 15 Jun 1984 (343-1986; Harris 1991). The brief descriptions submitted to the CBRC were considered by several members to be inadequate to confirm the identification of so rare a vagrant to California. Several experienced observers heard the bird’s song, but none offered a detailed description of it, and a taped recording made by one observer was apparently lost subsequently. The record ultimately received 6 supporting votes, but was considered by the four dissenters to be almost certainly good but unfortunately too poorly documented. EYEBROWED THRUSH Turdus obscurus. Two were reported with a flock of American Robins ( Turdus migratorius) at Pt. Reyes, MRN, 25 Feb 1990 (101- 1990). The observer had no previous experience with the species, and all Committee members agreed that the details were inadequate to support a first record for the state. The record was unanimously rejected. As with other recent claims of the Eyebrowed Thrush in California, the Committee felt that the birds were possibly confused with dull American Robins (which can show a pale supercilium), or perhaps with Varied Thrushes (Ixoreus naevius). WHITE WAGTAIL Motacilla alba. A report of two in urban San Francisco, SF, 1 1 Oct 1990 (194-1990) was considered inadequately documented by all ten Commit- tee members. The described black throat (incorrect for an October White Wagtail) and behavior (“swooping from tree to tree”) left little doubt that the birds were not even wagtails. YELLOW WAGTAIL Motacilla flava. One was reported at Arroyo de la Cruz, SLO, 23 Sep 1990 (37-1991). Several points in the description, including the call, suggested the Yellow Wagtail, but the views were less than ideal. The observer was not convinced of the bird’s identity until some time after the observation, and most Committee members were unconvinced. SPRAGUE'S PIPIT An thus spraguei i. One reported from the Tijuana River Valley, SD, 25 Nov 1990 (39-1991) received only two accept votes on the first round, with many Committee members expressing concern that the bird might have been a relatively unmarked American Pipit ( Anthus rubescens). The bird’s being seen in an open plowed field was atypical for the grass-loving Sprague’s. PHILADELPHIA V1REO Vireo philadelphicus. A report of one in Golden Gate Park, SF, 4 Oct 1983 (99-1987) ultimately failed by an 8-2 vote. One reported near the Carmel R. mouth., MTY, 17 Sep 1987 (367-1987) was rejected 4-6. Two were reported on Pt. Loma, SD, 20 Apr 1991 (92-1991); the Committee unanimously considered this report a misidentification because of an unconvincing description and the unprecedented date. Of 84 previously accepted California records, only ten are 24 CALIFORNIA BIRD RECORDS RECORDS NOT ACCEPTED, identification questionable, Cont. for spring, and the earliest of these is for 23 May: no previous report involved more than one individual. The rejected fall records more closely fit the expected pattern and received split votes in four circulations. The Philadelphia Vireo continues to have one of the highest rejection rates of any species reviewed by the CBRC. A bird collected at Harper Dry Lake. SBE, on 30 Sep 1990 (#SBCM 52709) and published as a Philadelphia Vireo (Am Birds 45:152) was reexamined and proved to be a Warbling Vireo ( Vireo giluus). YELLOW-GREEN VIREO Vireo flavouiridis. One reported from Upper Newport Bay, ORA, 29 Sep 1990 (154-1990) fits the pattern of vagrancy of this species in California, but the brief views and incomplete description led to a 1-9 first-round vote. YELLOW-THROATED WARBLER Dendroica dominica. One was reported seen on SE Farallon L, SF, 4 Jun 1978 (20-1988), and another was banded there 2-7 May 1980 (21-1988). No description of either bird was recorded at the time, although the former was noted in the Farallon journal to have been of the “white- lored race”; the latter was described only in recollections from two observers written 7 and 8 years, respectively, after the fact. As noted above, votes on such records generally break down along philosophical lines, as no Committee members raised serious doubts that the birds were correctly identified. These two records were defeated by 7-3 and 8-2 votes, respectively. PINE WARBLER Dendroica pinus. One at Pismo SB, Oceano, SLO, 27 Oct 1990 (41-1991) was considered inadequately documented and received a 1-9 decision on the second round. CERULEAN WARBLER Dendroica cerulea. One was reported in Arroyo Grande, SLO, 1 Oct 1989 (17-1990), but a majority of committee members felt the description contained features incorrect for this species. ‘PROTHONOTARY WARBLER Protonotaria citrea. One was seen by numerous observers in Zuma Canyon, Malibu, LA, 30 Sep-11 Oct 1979 (152-1987). How- ever, not a single observer submitted any real description (although several persons did indicate that the bird was missing its tail). Two Committee members rejected the record on its fourth and final circulation, each indicating that they believed a Prothonotary Warbler was present but that it was incumbent upon the Committee to affirm the adequacy of documentation submitted and not simply the likelihood that an identification was correct. SWAIN SON'S WARBLER Limnothlypis swainsoni. One reported on Gazos Creek, SM, 18 Jun 1990 (80-1990) was considered inadequately documented for a potential first state record. The date does accord well with the only other record of this species from the far West, of one in Apache County, Arizona, 12-13 Jun 1981 (Monson and Phillips 1981). WORM-EATING WARBLER Helmitheros uermiuorus. One was banded on SE Farallon L, SF, 5 Jun 1973 (204-1987), and another was observed there 28 May 1981 (22-1988). No descriptions of the former bird were available, and the latter bird was documented only with recollections supplied several years after the sighting. The records received eight and seven accept votes, respectively. CONNECTICUT WARBLER Oporornis agilis. One observed on SE Farallon I., SF, 5 Oct 1978 (24-1988) was supported primarily by the statement “perfect clean eyering on drab Oporornis although a majority of committee members voted to accept this record on all four circulations, it was ultimately defeated by a 6-4 vote. One reported from Galileo Hill Park, KER, 19 Sep 1990 (42-1991) was seen only briefly, although its reported walking behavior certainly suggested this species. 25 CALIFORNIA BIRD RECORDS RECORDS NOT ACCEPTED, identification questionable, Cont. MOURNING WARBLER Oporornis Philadelphia. One was banded on SE Farallon I., SF, 13-14 Sep 1981 (25-1988); no plumage description was provided, and although measurements presented suggested the Mourning Warbler, the impor- tant wing minus-tail measurement was at or near the overlap zone with MacGillivray’s (O. tolmiei); the record was narrowly rejected on an 8-2 vote. One reported from Gaviota SP, SBA, 13 Sep 1989 (155-1989) was felt by most Committee members to have probably been a Mourning, but several characters were inadequately described, and the yellow throat is now known not to eliminate all MacGillivray’s Warblers (Pyle and Henderson 1990). BAIRD’S SPARROW Ammodramus bairdii . One was reported from near Lake Earl, DN, 18 Sep 1987 (174-1988). This record circulated for four rounds, losing an accept vote each round and ending up at 6-4. There are only three accepted records of this species in California, each supported by a specimen or photograph. Any report based on written details only needs to be thorough. SNOW BUNTING Plectrophenax niualis. One was reported from SE Farallon I., SF, 26 Oct 1972 (251-1987) but was not supported by any description; a recollec- tion by one observer 15 years after the sighting was considered inadequate documen- tation by the three rejectors on the fourth and final circulation. RECORDS NOT ACCEPTED, NATURAL OCCURRENCE QUESTION- ABLE (IDENTIFICATION ACCEPTED) SWALLOW-TAILED GULL Creagrus furcatus. An adult was extensively photo- graphed at Pacific Grove and Moss Landing, MTY, 6-8 Jun 1985 (A1B; RAE, KLH, ASHf, JML, MJL, GMcC, JM, GNt, DR, PLTt, REWt; 79-1985); color photos were published in Am. Birds (39:958) and by Roberson (1985). The record was the first of this species north of Panama. The question of whether a Swallow-tailed Gull would more likely appear far from home on its own, or with human assistance, generated an emotionally charged debate. The species breeds near the equator, on islands off Colombia and in the Galapagos Islands. It disperses after breeding, so should not be considered sedentary. After four rounds, a discussion at our annual meeting, expert commentary, and hundreds of pages of documentation and comments, the vote on this record remains evenly split. Truly accidental records (that is, unprecedented records that defy easy explanation and may never be repeated) represent a major challenge for this or any committee, a challenge further complicated when the potential for captivity is difficult to assess. For example, below we reject a Purplish-backed Jay (Cyanacorax beecheyi), a species resident in Mexico. Vagrants of this species are not known, and jays are kept caged in Mexico. For most of us, this was a rather straightforward decision. In contrast are two examples from the other extreme: the Golden-cheeked Warbler from SE Farallon I., SF, 9 Sep 1971 (Lewis et al. 1974) and the Arctic Warbler found in Baja California on 12 Oct 1991 (Pyle and Howell 1993). Both of these records are unique but insectivorous passerines are not likely captives, and these two species are highly migratory (and therefore subject to navigational errors). Furthermore, the timing of these two records coincides with the species’ expected period of movement. These extremes are much easier to resolve. Such was not the case with the Swallow-tailed Gull, Many people have been surprised and dismayed at the level of emotion and animosity this record generated, both inside and outside the CBRC. The polarization engendered by this record reflects the differing philosophies discussed in our intro- ductory comments. Regardless of these arguments, nothing concerning the bird’s origin is provable. 26 CALIFORNIA BIRD RECORDS RECORDS NOT ACCEPTED, natural occurrence questionable (identifica- tion accepted), Cont. Those members who supported the Swallow-tailed Gull as more likely to have occurred on its own had many good arguments. First, gulls have an ability to wander, occasionally being found far from home. Examples could include the Ring-billed (Larus delawarensis) in Hawaii (Pyle, in comments) and the Laughing (L. atricilla) in the Marshall Islands (Garrett 1987), but the list of examples could be quite lengthy. Second, the Swallow-tailed is a highly pelagic gull. It is not sedentary, wintering along the coast of South America, where it has been found as far south as 36° S (Jehl 1973). Therefore, if a Swallow-tailed Gull traveling that distance traveled in the wrong direction, it would reach the latitude of California. Also, there are no known records of captives; zoos and other sources were not known to keep this species. Although this species occasionally follows boats, the likelihood of one’s being held captive then released in our waters must be remote. Finally, the El Nino/Southern Oscillation in 1983 may have been related to the bird’s arrival in California. In that year this regular phenomenon was exceptionally strong, and the entire population of this species was displaced from its breeding grounds. It was suggested that a young bird, presumably more susceptible to displacement, wandered into northern waters. As it molted into adult plumage it came ashore with other gulls, perhaps prospecting the area as a potential nesting site; this species generally remains at sea except to breed. The Committee members who could not support the record all felt that the bird was quite possibly a natural vagrant but could not place it on the state list because of the degree of uncertainty. Doubts centered on a Swallow-tailed Gull’s ability to get here on its own. This species is generally tied to cold waters, and would have to cross 2000 miles of warm water to reach the cold California Current. The lack of intervening records (only one questionable report from Panama) means that accep- tance of this record greatly expands the known range of this species and has wider implications for its biology. This species’ having reached 36° S may or may not indicate it could move to an equivalent northern latitude. The southernmost record may represent only an overshoot of the normal nonbreeding range, only a small percentage of the displacement necessary to bring a Swallow-tailed Gull to Califor- nia. Dissenters agreed that the proof of captivity is nonexistent; however, people capture birds all too regularly and the fact that one was photographed while being held on a boat shows that this possibility is real, though small. The Swallow-tailed Gull at Monterey occurred two years after El Nino, making any connection tenuous. El Nino recurs regularly, implying that another record should be expected. The Com- mittee concurred that an undisputed record well north of the Swallow-tailed Gull’s breeding range would be cause to reconsider this record. As discussed by Patten and Erickson (1994), we maintain a Supplemental List, created for species not on the state list whose identification is accepted and natural occurrence was rejected, in cases where the majority felt natural occurrence was plausible. At the 1994 annual meeting we unanimously voted to place the Swallow- tailed Gull on this list. PURPLISH-BACKED JAY Cyanocorax beecheyi. An unbanded immature was photographed in Calexico, IMP, 13 Dec 1990 (WRR; 102-1992); the bird had been present since late November 1990. The Living Desert Museum in Palm Desert, RIV, confirmed that two individuals of this species were housed there, but both were banded and accounted for. Committee members unanimously considered the bird an escapee rather than a natural vagrant; the species is a sedentary resident in western Mexico north to southern Sonora. Presumed escapees are known from El Paso, Texas, and from southern California; in fact, a pair apparently bred in the Tijuana 27 CALIFORNIA BIRD RECORDS RECORDS NOT ACCEPTED, natural occurrence questionable (identifica- tion accepted), Cont. River Valley, SD, in the 1980s (fide Guy McCaskie). This record once again raised the issue of the origin of Neotropical vagrants along our southern border. The Commit- tee believes that sedentary species are not likely to be natural vagrants, especially when found in urban areas. PAINTED BUNTING Passerina ciris. An adult male was seen in the Tijuana R. Valley, SD, 3 Nov 1979 (DP; 233-1988), and a male was seen in a yard in Coronado, SD, 3 Jun 1989 (EC; 1971989). These records received six and four accept votes, respectively. Records of adult male Painted Buntings always receive extra scrutiny, as are all records from urban regions near the Mexican border. UNRESOLVED RECORDS At the 1994 annual meeting, the CBRC voted to “table” three records of the Iceland Gull ( Larus glaucoides ) until the taxonomic status of that complex is better understood. Currently, Thayer’s Gull (L. thaperi) is considered a species separate from Iceland Gull, the latter including the nominate race and L. g. kumlieni. As of this writing the American Ornithologists’ Union’s Committee on Classification and Nomenclature has not yet made the anticipated move of merging thaperi and glaucoides. The darker thaperi may not even be ranked as a subspecies, if the cline leading into the paler kumlieni is too gradual. Whatever the ultimate taxonomic outcome, it appears hopeless for the Committee to attempt to judge the identity of an Figure 8. This gull, reported as an Iceland, was photographed in Bodega Bay, Sonoma Co. (7-1985). There is still confusion over its identity, and the Committee has not resolved this issue. 28 Photo bp Dan Nelson CALIFORNIA BIRD RECORDS Photo by Richard E. Webster Photo by Arnold Small Figures 9 and 10. This first-winter gull was photographed on 26 Jan 1986 near San Diego (15-1986). It shows the characters of subspecies kumlieni of the Iceland Gull, a most unexpected bird at this locale. The short bill, long primary extension, and barring on the tertials and tail are all visible in these pictures. 29 CALIFORNIA BIRD RECORDS UNRESOLVED RECORDS, Cont. individual bird when species limits are so uncertain. Zimmer (1991) discussed problems posed by variation in Kumlien’s Iceland Gull. The records are as follows: An adult was well studied and photographed at Bodega Bay, SON, 30 Dec 1984- 17 Jan 1985 (7-1985). The photographs (e.g., Fig. 8; see also Am. Birds 39:206) clearly show a "white-winged” gull in adult plumage. This bird appeared too white for thayeri or most kumlieni, but in this case the issue is not linked directly to the glaucoides-kumlieni-thayeri problem but instead concerned differentiation from the Glaucous Gull (L. hyperboreus). The race L. h. barrouianus, the one occurring in California, is the smallest race of the Glaucous Gull, and many Committee members wondered if the photographs could eliminate it. Substantial commentary was re- ceived from some of the most knowledgeable gull experts in the world. The debate continues, however, as opinions are split. A first-winter bird was photographed extensively near San Diego, SD, 18-25 Jan 1986 (15-1986). Figures 9 and 10 (see also AB 40:334) show an intriguing gull, far paler than thayeri; in fact, the bird appears to be at the pale end of kumlieni. The questions surrounding the validity of this record centered on the species-limit ques- tions, as well as on the likelihood of a “real” kumlieni occurring near the Mexican border, at the latitude of the southernmost limit of its winter range. Everyone agreed that the bird’s identity would not be given a second thought if a similar bird were in New England. An adult was well studied in Areata, HUM, 6-23 Feb 1987 (72-1987). Unlike the Bodega Bay adult, this bird did not look like nominate glaucoides but rather showed a primary pattern traditionally associated with kumlieni. Thus elimination of the Glaucous Gull was not a question. There was some conflict among the written descriptions in eye color, mantle color, etc., but everyone agreed that this bird “showed the characters” of kumlieni. Most Committee members reviewing these records feel that two or three of them represent the Iceland Gull as understood in the past. Much remains much to be learned regarding how far west the pale extreme of this complex breeds and migrates. We hope our declining to put a specific name on these birds does not discourage observers from giving attention to such gulls. CONTRIBUTORS Douglas W. Aguillard, Jonathan K. Alderfer, Brooks B. Allen, Brian W. Arnold, Dick Ashford (DAs), Michael J. Austin, Stephen F. Bailey, Alan Baldridge (A1B), Bruce Barrett, Alan D. Barron, Chris D. Benesh, Allyn Bissell (ABi), Milt Blatt, Arun Bose, N. Bruce Broadbooks, Eugene A. Cardiff, Dick Cunningham, Brian E. Daniels, Deborah L. Davidson, Paul DeBenedictis, David DeSante, Don Desjardin, Bruce E. Deuel (BEDe), Ann Dewart, Jon L. Dunn, Thomas M. Edell, Alan M. Eisner (AME), Ray Ekstrom, Barbara P. Elliott, Richard A. Erickson, Shawneen E. Finnegan, George H. Finger, Michael Force, Tom Forrest, Kimball L. Garrett, Daphne D. Gemmill, Edward D. Greaves, Marguerite B. Gross, Daniel A. Guthrie, Kem L. Hainebach, Robert A. Hamilton, Keith Hansen, Richard R, Hansen, Stanley W. Harris, Jim Havlena (JHa), Karen Havlena (KHa), Gjon Hazard, Bob Hefter (BHe), Jo Heindel, Matthew T. Heindel, Mitch Heindel, Tom Heindel, R. Philip Henderson, Kevin Hintsa, Alan S. Hopkins, Bryan Huehnken (BHu), Richard G. Jeffers, H. Lee Jones (HLJ), Clay Kempf, Christine H. Koundakjian, Theodore H. Koundakjian, Jeri M. Langham (JML), Greg W. Lasley, Peter La Tourette, Eari Lebow, Paul E. Lehman, Robin Leong, Gary S. Lester, Lauren P. Lester, Eric Lichtwardt, Michael J. Lippsmeyer, Curtis A. Marantz, Guy McCaskie, John McCormick (JMc), John McKean (JMk), Robert L. McKernan, Anthony Mercieca, Peter J. Metropulos, John 30 CALIFORNIA BIRD RECORDS Michael (JMi), Kathy C. Molina, Randy J. Moore, Joseph Morlan, Scott W. Morrical, Gary Neil, Rod Norden, John O’Brien, Michael O’Brien, Bill O’Connell, Jean Olive, John Osner (JOs), Bob Pann, Deborah Parker-Chapman, Benjamin D. Parmeter, Michael A. Patten, Mike Prather, Peter Pyle, Kurt A. Radamaker, Peter Radcliff (PRa), David Rice (DRi), Robert J. Richmond, Michael F. Robbins, Don Roberson, Jim Robertson, Geoff Rogers, Philip Rostron, Larry Sansone, Luis Santaella (LSa), Gus Sawyer, David Seals (DSe), David A. Sibley, Rich Stallcup, Tom Staudt, David Stejskal (DSt), Timothy Steurer, David L. Suddjian, Monte M. Taylor, Scott B. Terrill, Ronald S, Thorn, Robert F. Tintle, Kent Van Vuren, David Venner, Susan Walker, Joan Walsh (JWa), Richard E. Webster, Brian J. Weed, Herbert Williams, Douglas R. Willick, John C, Wilson, John Wright (JWr), David G. Yee, C. F. Yocum, Carol Yoder, Kevin J. Zimmer. ACKNOWLEDGMENTS For all CBRC reports we routinely solicit input from outside reviewers. The insights of others are welcome and necessary. We thank the following for their comments on some of the records we reviewed: Per Alstrom, Steven F. Bailey, Eirik A. T. Blom, Steven W. Cardiff, Donna L, Dittmann, Davis Finch, Daniel D. Gibson, Michel Gosselin, the late Peter J. Grant, Peter Harrison, Ted Hoogendoorn, the late Burt L. Monroe, Jr., Dennis Paulson, J. V. Remsen, Jr., David Sibley, Stu Tingley, and Thede Tobish. The following past and present Committee members voted on this report’s records: Stephen F. Bailey, Louis R. Bevier, Jon L. Dunn, Richard A. Erickson, Shawneen E. Finnegan, Kimball L. Garrett, Matthew T. Heindel, Jeri M. Langham, Paul E. Lehman, Michael J. Lippsmeyer, Curtis A. Marantz, Guy McCaskie, Joseph Morlan, Michael A. Patten, Peter Pyle, Don Roberson, Rich Stallcup, and Scott B. Terrill. LITERATURE CITED American Ornithologists’ Union. 1957. Check-list of North American Birds, 5th ed. Am. Ornithol. Union, Washington, D.C. American Ornithologists’ Union. 1983. Check-list of North American Birds, 6th ed. Am. Ornithol. Union, Washington, D.C. Bevier, L. R. 1990. Eleventh report of the California Bird Records Committee. W. Birds 21:145-176. Binford, L. C. 1983. Sixth report of the California Bird Records Committee. W. Birds 14:127-145. Daniels, B. E., Hays, L., Hays, D., Morlan, J., and Roberson, D. 1989. First record of the Common Black-Hawk for California. W. Birds 20: 11-18. Farrand, J., Jr. 1983. The Audubon Society Master Guide to Birding, vol. 1. Knopf, New York. Garrett, K. L. 1987. Occurrence of the Laughing Gull in the Marshall Islands. ‘Elepaio 47:7. Harris, S. W. 1991. Northwest California Birds. Humboldt State Univ. Press, Areata, CA. Hirschfield, E. 1986. Rufous Turtle Dove in Europe. Dutch Birding 8:77-84. Howell, S. N. G., Spear, L. B., and Pyle, P. 1994. Identification of Manx-type shearwaters in the eastern Pacific. W. Birds 25:169-177. Jackson, G. D. 1992. Field identification of teal in North America, female-like plumages. Part II: Garganey and Baikal Teal. Birding 24:214-223. 31 CALIFORNIA BIRD RECORDS Jehl, J. R. , Jr. 1973. The distribution of marine birds in Chilean waters in winter. Auk 90:114-135. Jehl, J. R., Jr. 1982. The biology and taxonomy of Townsend’s Shearwater. Gerfaut 72:121-135. Johnson, N. K., and K. L. Garrett, 1974. Interior bird species expand breeding ranges into southern California. W. Birds 5:45-56. Kaufman, K. 1991. The changing seasons: Autumn 1990. Am. Birds 45:63-66. Langham. J. M. 1991. Twelfth report of the California Bird Records Committee. W. “Birds 22:97-130. Laudenslayer, B., Grenfell, W., and Zeiner, D. 1991. A checklist of the amphibians, reptiles, birds, and mammals of California. Calif. Fish and Game 77:109-141. Lewis, T. J., Ainley, D. G., Greenberg, D., and Greenberg, R. 1974. A Golden- cheeked Warbler on the Farallon Islands. Auk 91:411-412. McCaskie, G. 1990. First record of the Band-rumped Storm-Petrel in California. W. Birds 21:65-68. McCaskie, G., and Roberson, D. 1992. First record of Stejneger’s Petrel in Califor- nia. W. Birds 23:145-152. McCaskie, G., and Webster, R. E. 1990. A second Wedge-tailed Shearwater in California. W. Birds 21:139-140. Monson, G., and Phillips, A. R. 1981. Annotated Checklist of the Birds of Arizona, 2nd ed. Univ. of Ariz. Press, Tucson. Ouellet, H. 1993. Bicknell’s Thrush: Taxonomic status and distribution. Wilson Bull. 105:545-572. Patten, M. A. 1993. First record of the Common Pochard for California. W. Birds 24:235-240. Patten, M. A., and Erickson, R. A. 1994. Fifteenth report of the California Bird Records Committee. W. Birds 25:1-34. Patten, M. A., and Heindel, M. T. 1994. Identifying Trumpter and Tundra Swans. Birding 26:306-318. Peterson, A. 1992. An extraordinary backyard. Birders’ J. 1:339. Prater, A. J., Marchant, J. H., and Vuorinen, J. 1977. Guide to the Identification and Ageing of Holarctic Waders. Br. Trust Ornithol., Tring, England. Pyle, P, and Henderson, P. 1990. On separating female and immature Oporornis warblers in fall. Birding 22:222-229. Pyle, P, and Howell, S. N. G. 1993. An Arctic Warbler in Baja California, Mexico. W. Birds 24:53-56. Pyle, P, and McCaskie, G. 1992. Thirteenth report of the California Bird Records Committee. W. Birds 23:97-132. Roberson, D. 1985. Monterey Birds. Monterey Peninsula Audubon Soc., Carmel, CA. Roberson, D. 1986. Ninth report of the California Bird Records Committee. W. Birds 17:49-77. Roberson, D. 1993. Fourteenth report of the California Bird Records Committee. W. Birds 24:113-166. Roberson, D., and Bailey, S. F. 1991. Cookilario petrels in the eastern Pacific Ocean — identification and distribution. Am. Birds 45:399-402, 1067-1081. 32 CALIFORNIA BIRD RECORDS Spear, L. B., Howell, S, N. G., and Ainley, D. G. 1992. Notes on the at-sea identification of some Pacific gadfly petrels (genus Pterodroma). Colonial Waterbirds 15:202-218. Stallcup, R, ( Morlan, J,, and Roberson, D. 1988. First record of the Wedge-tailed Shearwater in California. W. Birds 19:61-68. Thompson, C. W. 1991. The sequence of molts and plumages in Painted Buntings and implications for theories of delayed plumage maturation. Condor 93:209- 235. Webster, R. E., Morlan, J., and Roberson, D. 1990. First record of the Sooty Tern in California. W. Birds 21:25-32. Zimmer, K. J. 1991. Plumage variation in “Kumlien’s” Iceland Gull. Birding 23:254- 269. Accepted 12 November 1994 Yellow-throated Warbler Sketch by Edward Rooks 33 GREATER SANDHILL CRANE NESTING AND PRO- DUCTION IN NORTHEASTERN CALIFORNIA, 1988 CARROLL D. LITTLEFIELD, Malheur Field Station, HC 72-Box 260, Princeton, Oregon 97721 (present address: HCR 4-Box 212, Muleshoe, Texas 79347) The population of the Greater Sandhill Crane (Grus canadensis tabida ) wintering in the Central Valley was listed as a sensitive species by the U.S. Fish and Wildlife Service in 1982 and as a threatened species by the state of California in 1983. Many of these cranes breed in northeastern California. In 1988, I surveyed the species’ California breeding range, locating nests and following up the fate of selected pairs. Except at Modoc National Wildlife Refuge (NWR), Modoc County, little is known about the nesting biology and success of the Sandhill Crane in California. The objective of this report is to provide such information. STUDY AREA AND METHODS The study area included the six northeastern California counties where G. c. tabida is known to nest, from the Oregon and Nevada lines west to Montague, Siskiyou County, and south to Sierraville, Sierra County. I surveyed all known and potential Sandhill Crane breeding habitat within this region, examining nests in Big and Ash Creek valleys, Lassen County, and in Jess, Big, and Surprise valleys, near Likely and Alturas, and at Goose Lake, Modoc NWR, and Reservoir C, Modoc County. I counted broods at these locations and at Honey Lake Wildlife Area (WA), in and near Lassen National Forest, in Willow Creek Valley, and on the Madeline Plains, Lassen County, in Sierra and Indian valleys, Plumas County, at Lower Klamath NWR, Siskiyou County, and in and near the Modoc National Forest, Modoc County. In addition, R. Johnstone counted broods elsewhere in Siskiyou County. I did not search the Fall River Valley, in Shasta and Lassen counties, for broods, even though cranes had established territories there in the spring, as there was no water in the nesting marshes by mid-June. Nests were located between 28 April and 19 May. After locating a nest, I recorded the surrounding vegetation type and height, water depth, and incubation stage. Incubation stage was determined by flotation (Westerskov 1950). I considered incubating cranes poorly concealed when visible at distances >75 m, fairly well concealed when visible at 10 to 75 m, and well concealed when visible only at <10 m. After the normal 30-day incubation period, I revisited the nests and determined their fates. I surveyed selected nesting areas for broods when fledged or nearly fledged young were still within or near their natal territory. RESULTS I found nests at eight sites in Modoc and Lassen counties, mostly in Modoc County, home of 59.2% of the 276 known pairs of G. c. tabida in California (Littlefield et al. 1994). The sample size was limited because Western Birds 26:34-38, 1995 34 SANDHILL CRANE NESTING drought persisting from the previous winter continued through spring and summer 1988, resulting in many pairs’ never attempting to nest (Littlefield 1989). Only in Modoc County, particularly near Alturas, did appreciable (>7 cm) rain fall, in late April and early May. This failure of Sandhill Cranes to breed in northeastern California during drought was paralleled in the late 1940s and early 1950s (Naylor et al. 1954). Of the 56 nests I examined, 22 were on the Modoc NWR, 14 were in Big Valley (in the Ash Creek WA), 8 were in the Ash Creek Valley, 4 were in Jess Valley, 3 were near Goose Lake, 2 were near Likely, and 1 each were in the Surprise Valley, near Alturas, and adjacent to Reservoir C. Nesting Biology and Ecology Egg-laying began in mid-April (earliest 1 1 April), with most pairs laying in late April (latest 1 1 May). At least one pair nested later, as 6 km northwest of Likely on 9 August 1988 I found a chick under 4 weeks old. It must have hatched from an egg laid between 15 and 21 June. Most nests were in open wet meadows. Of the 48 nests whose surround- ing vegetation was recorded, 21 (44%) were in rushes ( Juncus and Eleocharis spp.), 9 (19%) were in Broad-fruited Burreed ( Sparganium eurycarpum), 5 (10%) were in grasses, 4 (8%) were in sedges (Carex spp.), 3 (6%) were in Hardstem Bulrush (Scirpus acutus), and 1 (2%) was in Common Cattail ( Typha latifolia). The other five (10%) were in various combinations of these vegetation types. The height of the vegetation surrounding the nests averaged 29.6 cm, and water depths ranged from 0 to 33.5 cm, averaging 6.2 cm. Forty-five (80%) nests were poorly con- cealed, 10 (18%) were fairly well concealed, and only one (2%) was well concealed. The size of the complete clutch was determined in 42 nests, of which 36 had two eggs, five had one egg, and one had three eggs, for an average of 1.91 eggs per clutch. Nest Success The average nest success for all areas combined was 37.5%. Thirty clutches (54%) were destroyed by predators, Coyotes ( Canis latrans ) taking 17, Common Ravens (Coruus corax) taking 6, Raccoons ( Procyon lotor ) taking 5, and unknown predators taking 2. Three clutches were infertile, and two were abandoned. Success rates varied from site to site. Modoc NWR (0.8 km S of Alturas). Modoc NWR was one of the few nesting areas having adequate water in 1988. Of the 22 nests examined on the refuge, 11 had eggs that hatched. Raccoons were the most important predator, destroying four clutches. Common Ravens and unidentified preda- tors each destroyed two. Two clutches were infertile and one was aban- doned. Big Valley (Ash Creek WA, 4.8 km NNE of Bieber). Here the success rate was 36% (5 of 14 clutches). Lack of water probably contributed to this low success. Coyotes destroyed seven clutches, all in the southwest portion of the wildlife area; no clutches were lost in the northern portion. One clutch was destroyed by a Common Raven and another was infertile. 35 SANDHILL CRANE NESTING Ash Creek Valley (16 km W of Madeline). This valley had very little water throughout the nesting period, and all eight nests examined were unsuc- cessful. All were crowded into a 10-ha burreed wetland that had been grazed the previous winter by livestock. Nests were poorly concealed, being clearly visible from 1.6 km away. Water depths averaged 6.2 cm, and coyotes apparently had little difficulty in locating and destroying six of (he clutches. I saw two coyotes near the nesting marsh in May, indicating a den was nearby. A Common Raven consumed one clutch and another was abandoned. Jess Valley (14 km E of Likely). Even though all four crane nests examined in this valley were poorly concealed, two clutches hatched. The other two were destroyed by coyotes. Water depths at nest sites averaged only 1.3 cm. W. Fluorney (pers. comm.), who owns a large percentage of the valley, reported that in the past losses of crane nests were due primarily to flooding. He reported some coyotes and raccoons in the area but few ravens; I did note one pair of ravens in May and June. Goose Lake (4.8 km WNW of Davis Creek). I found only three nests near Davis Creek in May, though an additional pair with a single chick was there in June. The three nests were within an enclosed ungrazed marsh 0.8 km south of Goose Lake on the Lakeshore Ranch. Both clutches in the two nests over water >30 cm deep hatched. The third, among rushes where water had recently receded to 2 cm, was destroyed by a coyote. Two more pairs of cranes apparently nested in the same marsh, but I could not locate their nests. Likely (1.6 km WNW). Of the two nests I found in this region, one was over 4 cm of water and was subsequently lost to a coyote, seen within 0.4 km of the nest on the day it was discovered, 19 May. The second nest was in a stand of Hardstem Bulrush over 23 cm of water; it was eventually destroyed by a raccoon. There were four other pairs of cranes in the same area but I noted no other nesting activity. On 19 May 1988, most meadows around Likely were dry. Surprise Valley (29 km E of Alturas). I found only one nest in the Surprise Valley in 1988, although 56 pairs of cranes occupied territories there and four of these fledged a single young each. Fifteen of these were within 3.5 km of Eagleville. The single nest was in a stand of Hardstem Bulrush over 9.5 cm of water on 17 May, but the two eggs were lost to a Common Raven in early June. Most of the Surprise Valley remained dry throughout the 1988 breeding season. Reservoir C (22 km NW of Alturas). One pair nested 0.8 km south of the reservoir adjacent to Forest Service Road 43N18 in a small wetland among Western Junipers ( Juniperus occidental is). The nest was composed of rushes, situated over 20 cm of water. The pair was successful in hatching the two eggs, but neither the pair nor young was seen at this site thereafter. The family could have moved south onto the Antelope Plains, as B. Deuel (pers. comm.), during an aerial survey, saw a pair there in May. Alturas (3.2 km E). This was the first nest located in 1988, the only one in cattails. Unfortunately, one member of the pair died after colliding with an electric transmission line before 10 May. The nest was in a small cattle- 36 SANDHILL CRANE NESTING trampled marsh with little water. The eggs were consumed by a Common Raven, seen during my follow-up visit. Recruitment of Young I recorded only 20 young fledged by 224 pairs, yielding a recruitment rate of 4.5%. Of 18 broods observed, two (11%) were of two chicks; 16 (89%) contained a single chick. The two-chick broods were at the Modoc and Lower Klamath national wildlife refuges. Of the 20 young, 10 were raised at Modoc NWR (C. Bloom pers. comm.), 4 were in the Surprise Valley, 1 was near Likely, 1 was in Jess Valley, 2 were at Lower Klamath NWR (J. Mainline pers. comm.), and 2 were elsewhere in Siskiyou County. In addition, a pair at Buchanan Flat, Modoc County, had two well-devel- oped chicks in mid-July, but it was not determined if these survived to fledge. DISCUSSION The nest success and recruitment rate of G. c. tabida in northeastern California in 1988 were low, most likely as a result of drought. R. Schlorff (unpublished data) surveyed several of the cranes’ nesting areas in 1987, recording 10 young in the Surprise Valley, 2 near Likely, 2 at Goose Lake, and 1 in Big Valley, for a total of 15 young at these four sites. Only five young were located at these same sites in 1988, indicating recruitment rates were considerably higher in the region in 1987. Indeed, unlike elsewhere in the Pacific states, in northeastern California Greater Sandhill Crane numbers have been increasing at least since the early 1970s (Littlefield 1982, 1989). Although the number of nests examined was limited and observations were restricted to a single drought year, the information produced by this study will provide a basis for more detailed studies in the future. Additional data on nesting success, fledging success, predation rates, habitat prefer- ences, disturbance factors, and brood chronology need to be gathered and analyzed, especially in relation to variation in precipitation, to enable the development of management strategies to ensure the continued survival and increase of the Greater Sandhill Crane in California. SUMMARY The 224 pairs of the Greater Sandhill Crane surveyed on the Modoc Plateau of northeastern California fledged only 20 young in 1988. This low rate was partially a result of drought drying the marshes where the cranes nest, giving predators (mainly coyotes) easier access to nests. Predators destroyed 30 of the 56 clutches found, and another 5 were infertile or abandoned. Hatching success reached 50% only at the Modoc National Wildlife Refuge near Alturas, the only area receiving significant relief from drought via spring rains. 37 SANDHILL CRANE NESTING ACKNOWLEDGMENTS This study was funded by the Nongame Bird and Mammal Section of the California Department of Fish and Game. Of the numerous people who contributed to the study, I am particularly indebted to Ron Schlorff of the California Department of Fish and Game, who was responsible for initiat- ing, coordinating, and who also participated in the field work. Clark Bloom and Tom Melanson, U.S. Fish and Wildlife Service, Modoc NWR, provided data on nest locations and other information on cranes in the Alturas area, and Rich Johnstone provided data on cranes in Siskiyou County. Robert Holloway assisted in most phases of the study, and to all of these and others I extend my sincere thanks. I also express my sincere thanks to Dan Airola, Tim Manolis, and Bruce Deuel for suggestions and corrections of the manuscript. LITERATURE CITED Littlefield, C. D. 1982. The status and distribution of Greater Sandhill Cranes in California, 1981. Admin. Rep. 82-1, Calif. Dept. Fish and Game, 1416 Ninth St., Sacramento, CA 95814. Littlefield, C. D. 1989. Status of Greater Sandhill Crane breeding populations in California, 1988. Report to Nongame Bird and Mammal Section, Calif. Dept. Fish and Game, 1416 Ninth St., Sacramento, CA 95814. Littlefield, C. D., Stern, M. A., and Schlorff, R. W. 1994. Summer distribution, status, and trends of Greater Sandhill Cranes in Oregon and California. North- western Naturalist 75:1-10. Naylor, A, E., Miller, A. W., and Foster, M. E. 1954. Observations on Sandhill Cranes in northeast California. Condor 56:224-227. Westerskov, K. 1950. Methods for determining the age of game bird eggs. J. Wildlife Mgmt. 14:56-67. Accepted 30 August 1994 38 FIRST RECORD OF THE MARBLED MURRELET AND THIRD RECORD OF THE ANCIENT MURRELET FOR MEXICO RICHARD A. ERICKSON and ROBERT A. HAMILTON, LSA Associates, 1 Park Plaza, Suite 500, Irvine, California 92714 STEVE N. G. HOWELL and PETER PYLE, Point Reyes Bird Observatory, 4990 Shoreline Highway, Stinson Beach, California 94970 MICHAEL A. PATTEN, Department of Biology, University of California, Riverside, California 92521 We discovered two Marbled Murrelets ( Brachyramphus marmoratus marmoratus) and an Ancient Murrelet ( Synthliboramphus aritiquus) at Ensenada, Baja California, in the early afternoon of 9 January 1994. We first saw the Marbled Murrelets from the beach just south of the southern jetty forming Ensenada harbor. Wishing to document the record more fully, and to consider further the possibility that the birds were of the more vagrancy-prone Asiatic race (B. m. perdix), we rented a boat at the harbor. After closely viewing and photographing the Marbled Murrelets on the water, we found the Ancient Murrelet along an inner jetty of the harbor. MARBLED MURRELETS The two Marbled Murrelets (Figures 1 and 2) remained close to one another the entire time we observed them, diving and foraging over the sandy bottom. They appeared healthy; their alert posture, with heads and tails up, contrasted with that of the Ancient Murrelet seen later. They called several times as we slowly approached them by boat, giving soft quack-like notes (“eh-eh”; S. B. C. Dechesne, unpubl. data) typical of the species. Presumably the same birds were seen again on 1 1 January by R. E, Webster (in litt.), but they were not found later in the month, despite considerable searching by K. Radamaker, A. M. Sada, L. Santaella, and T. E. Wurster (pers. comm.). Distinction between North American and Asiatic Marbled Murrelets Our descriptions and photographs show that the Ensenada birds were B. m. marmoratus in basic plumage, not B. m. perdix. Marmoratus is primarily resident in its North American breeding range, which extends from southern Alaska to Santa Cruz County, California (AOU 1983, Marshall 1988). Perdix occurs at similar latitudes in Asia, ranging from Kamchatka and the Commander Islands south to Japan and Korea (AOU 1983). Except in coastal southern California, all previous North American records of the Marbled Murrelet away from the general breeding range have been of perdix (Sealy et al. 1991, Sibley 1993). After examining two specimens of perdix at the California Academy of Sciences and observing a live bird in Ontario, Sibley (1993) suggested field characters useful in distinguishing the two forms of the Marbled Murrelet in basic plumage. On 26 January 1994, Erickson examined specimens at the Western Birds 26:39-45, 1995 39 MARBLED AND ANCIENT MURRELET Figure 1. Marbled Murrelets at Ensenada, Baja California, 9 January 1994. Note the typical murrelet shape and general plumage pattern, white scapulars, extensively white flanks and, in contrast to the similar Kittlitz's Murrelet, longer bill and dark face. The largely white nape and extent of dark below the eye indicate the nominate race rather than B. m. perdix. The ages of these birds are unknown: although Bent (1919) suggested that first winter birds are blacker and less gray than adults, Carter and Stein (in press) stated that “by early fall, older juveniles are not distinguishable in the field from after-hatching-year birds in basic plumage. " Photo by Robert A. Hamilton Figure 2. Marbled Murrelet at Ensenada 9 January 1994. The nearly complete white nuchal collar typical of B.m. marmoratus is evident here. Photo by Robert A. Hamilton 40 MARBLED AND ANCIENT MURRELET Museum of Vertebrate Zoology, University of California, Berkeley (MVZ), including a large series of marmoratus and eight perdix , all but one in basic plumage. These specimens revealed that Sibley’s recommendations (quoted here and illustrated in Figure 3; see also useful photographs of perdix in Am. Birds 34:137, 37:206, 48:105 and Natl Audubon Soc. Field Notes 48:291) should be tempered somewhat. 1. “ Perdix shows an entirely dark hindneck; [marmoratus has a] nearly complete white nuchal collar.” This, the most obvious distinction between the two forms, was borne out by all of the MVZ specimens, as well as both specimens of perdix at the San Diego Natural History’ Museum (P. Unitt pers. comm.). Caution is essential, however, as specimens showed that some juvenile and molting marmoratus can have hindneck patterns sug- gestive of perdix. Figure 3. Basic plumages of Asiatic (upper) and American (lower) Marbled Murrelets. This drawing of perdix is based entirely on an individual on the St. Lawrence River, Ontario/New York, in October 1993; the drawing of marmoratus is based on photos and sketches of numerous birds. See text for further discussion. Sketch by David Sibley (from Birders’ Journal 2:211) 41 MARBLED AND ANCIENT MURRELET 2. “Perdix shows ... less black below the eye.” This was consistent with all MVZ specimens. 3. “Perdix shows ... less black on the sides of the breast.” This, too, was consistent with all MVZ specimens in basic plumage, though some juveniles of marmoratus lacked extensive dark sides of the breast. 4. “ Perdix shows ... bolder white eye-arcs,” (i.e., broken white eye-rings). This mark was earlier suggested by Harrison (1983). Although the MVZ specimens showed this difference to prevail on average, there was complete overlap, with some marmoratus showing bold eye-arcs and some perdix showing indistinct eye-arcs. 5. “Perdix [is] entirely dark above the gape; marmoratus shows a broad pale stripe above the gape.” Again, the MVZ specimens showed this difference to be of averages only, there being complete overlap in both directions. 6. “Presumably typical of perdix is a pair of pale patches on the nape, divided by a darker gray stripe down the center of the nape.” This mark was not matched by any of the MVZ marmoratus but was not shown by most of the perdix either; only two specimens had distinctive patches. As alluded to previously, juvenal and transitional plumages of marmoratus may show nape patches if incoming white feathers appear there first. 7. The bill of perdix “averages 30% longer” than marmoratus. Sealy et al. (1982) found a complete separation at an exposed culmen length of 18 mm. Perdix also averages larger in body bulk, 296 g, versus 225 g in marmoratus (Piatt et al. 1994). These differences are likely to be difficult to ascertain in the field, especially on lone birds. Note also that Sealy (1975) found fledgling marmoratus to weigh an average of only 70.5% of adults and to have exposed culmen lengths averaging 83.8% of adults’. In all features, the Ensenada birds were typical of marmoratus. Southern Records of the Marbled Murrelet on the Pacific Coast of North America South of its breeding range, the Marbled Murrelet is nearly annual in the California Current as far south as Point Arguello, Santa Barbara County, primarily in fall and winter (Roberson 1985, Marantz 1986, Lehman 1994). It is irregular farther south, with most records for the Santa Barbara and Los Angeles areas (Webster et al. 1980, Garrett and Dunn 1981, Lehman 1994, Am. Birds 35:227, 36:331, 36:894). As it did with the Ancient Murrelet, the winter of 1979-80 brought exceptional numbers of Marbled Murrelets to central and southern California (Am. Birds 34:201, 34:303, 34:307; Garrett and Dunn 1981), including the southernmost previously recorded: two at Imperial Beach, San Diego County 15-16 December 1979. Unitt (1984) considered the racial identity of the Imperial Beach birds inconclusive, lacking a specimen, but a photograph in Am. Birds 34:307 clearly shows the white hindneck and extensive black below the eye, typical of marmoratus. Except for the birds at Ensenada, the species was unrecorded south of Santa Barbara in the winter of 1993-94 (Natl. Audubon Soc. Field Notes 48:248). 42 MARBLED AND ANCIENT MURRELET ANCIENT MURRELET The Ancient Murrelet at Ensenada was easily approached as it swam just off a jetty within the harbor (Figure 4). Its rather slow movements and slouching manner suggested to us that it was not healthy. Pyle refound the bird later in the afternoon, but it was not seen thereafter, despite the concerted efforts of K. Radamaker, A. M. Sada, L. Santaella, R. E. Webster, and T. E. Wurster (pers. comm.) through the end of the month. There was an irruption of this species in California in the winter of 1993-94, with records from most southern coastal counties and an exceptional inland bird at San Pablo Reservoir, Contra Costa County, 13-22 November {Am. Birds 48:149, 48:152; Natl. Audubon Soc. Field Notes 48:248). Among the alcids, the Ancient Murrelet is one of the most prone to vagrancy. It has been recorded as far from its normal North Pacific range as Quebec, Ohio, Louisiana, and England (Munyer 1965, Verbeek 1966, AOU 1983, Waldon 1994). Prior to the one at San Pablo Reservoir, there were only three confirmed inland records for California, of single birds at the north end of the Salton Sea on 16 June 1984 {Am. Birds 38: 1062) and 23 May 1987 {Am. Birds 41:488) and at Mono Lake on 9 December 1985 (Gaines 1988). The location of an undated specimen from Palm Springs reported by Garrett and Dunn (1981) is unknown; we consider the record inconclusive. Figure 4. Ancient Murrelet at Ensenada, 9 January 1994. The pale bill and gray upperparts contrasting with the uncrested black head are characteristic of this species. The criteria for assessing an Ancient Murrelet s age in winter are poorly known, but the apparently unworn primary coverts visible here may suggest this was an adult. Photo by Robert A. Hamilton 43 MARBLED AND ANCIENT MURRELET Along the California coast, the Ancient Murrelet is annual south to San Luis Obispo County (Marantz 1986); it occasionally irrupts to the south (Garrett and Dunn 1981, Lehman 1994). The winter of 1979-80 was especially noteworthy, producing the greatest flight ever recorded in south- ern California (Am, Birds 34:201, 34:307; Garrett and Dunn 1981). Even in that year, very few birds were seen in southern California after the first week of January (Am. Birds 34:307). There are two previous records of Ancient Murrelets in Mexican waters (Howell and Webb in press), of one collected near Ensenada on 25 December 1927 (Grinnell 1928) and five seen near Los Coronados Islands on 24 February 1980, during the invasion (Am. Birds 34:307), not in 1975 as stated by Wilbur (1987). SUMMARY In basic plumage, the two subspecies of the Marbled Murrelet, Brachyramphus m. perdix and B. m. marmoratus, differ as follows: perdix has an entirely dark hindneck, a narrow band of black below the eye, and limited black on the sides of the breast; marmoratus has a nearly complete white nuchal collar, more black below the eye, and extensive black on the sides of the breast. Other plumage characteristics are inconsistent or are average differences only. In addition to the two we photographed at Ensenada, Baja California, on 9 January 1994, all Marbled Murrelet specimens and photographs that we have examined from coastal California south of the species’ breeding range have been marmoratus on the basis of these criteria. An Ancient Murrelet we photographed at Ensenada on this same date was at the southernmost locality recorded for the species. ACKNOWLEDGMENTS El Maru skillfully maneuvered his boat to allow our observation and photography of these birds. Jon L. Dunn alerted us to David Sibley s published note, and Sibley allowed us to reproduce his drawings. Carla Cicero and Ned K. Johnson arranged for examination of murrelet specimens at the Museum of Vertebrate Zoology, University of California, Berkeley, as did Kimball L. Garrett at the Los Angeles County Museum of Natural History. Stephen F. Bailey, Harry R. Carter, James W. Cornett, Sharon B. C. Dechesne, Thomas M. Edell, Shawneen E. Finnegan, Guy McCaskie, Janet L. Stein, and Walter Wehtje were helpful in our research. Spencer G. Sealy and Philip Unitt offered numerous constructive comments on the manuscript. We thank them all. LITERATURE CITED American Ornithologists’ Union. 1983. Check-list of North American Birds, 6th ed. Am. Ornithol. Union, Washington, D.C. Bent, A. C. 1919. Life histories of North American diving birds. U.S. Natl. Mus. Bull. 107. Carter, H. R., and Stein, J. L. In press. Molts and plumages in the annual cycle of the Marbled Murrelet, in Conservation Assessment for the Marbled Murrelet, An Interagency Scientific Evaluation. (C. J. Ralph, G. L. Hunt, Jr., J. F. Piatt, and M. G. Raphael, compilers). U.S. Forest Service, Areata, CA. 44 MARBLED AND ANCIENT MURRELET Gaines, D. A. 1988. Birds of Yosemite and the East Slope. Artemisia Press, Lee Vining, CA. Garrett, K., and Dunn, J. 1981. Birds of Southern California: Status and Distribu- tion. Los Angeles Audubon Soc., Los Angeles. Grinnell, J. 1928. A distributional summation of the ornithology of Lower California. Univ. Calif. Publ. Zool. 32: 1-300. Harrison, P. 1983. Seabirds: An Identification Guide. Croom Helm, London. Howell, S. N. G., and Webb, S. In press. A Guide to the Birds of Mexico and Northern Central America. Oxford Univ. Press, Oxford, England. Lehman, P. E. 1994. The Birds of Santa Barbara County, California. Vertebrate Museum, Univ. of Calif., Santa Barbara. Marantz, C. 1986. The birds of San Luis Obispo County, California: Their status and distribution. Senior thesis, Calif. Polytechnic State Univ., San Luis Obispo. Marshall, D. B. 1988. Status of the Marbled Murrelet in North America: With special emphasis on populations in California, Oregon, and Washington. U.S. Fish and Wildlife Service, Biological Report 88(30). Munyer, E. A. 1965. Inland wanderings of the Ancient Murrelet. Wilson Bull. 77:235-242. Piatt, J. F., Friesen, V., and van Vliet, G. 1994. Status of a “new” rare alcid, the Long-billed Murrelet. Abstracts from the 1994 annual meeting. Pac. Seabirds 21:47-48. Roberson, D. 1985. Monterey Birds. Monterey Peninsula Audubon Soc., Carmel, CA. Sealy, S. G. 1975. Aspects of the breeding biology of the Marbled Murrelet in British Columbia. Bird -Banding 46:141-154. Sealy, S. G., Carter, H. R., and Alison, D. 1982. Occurrences of the Asiatic Marbled Murrelet [Brachyramphus marmoratus perdix (Pallas)] in North America. Auk 99:778-781. Sealy, S. G., Carter, H. R., Shuford, W. D., Powers, K. D., and Chase, C. A. III. 1991 . Long-distance vagrancy of the Asiatic Marbled Murrelet in North America, 1979-1989. W. Birds 22:145-155. Sibley, D. 1993. An Asiatic Marbled Murrelet in Ontario. Birders’ J. 2:276-277. Unitt, P. 1984. The birds of San Diego County. San Diego Soc, Nat. Hist. Memoir 13. Verbeek, N. A, M. 1966. Wanderings of the Ancient Murrelet: Some additional comments. Condor 68:510-511. Waldon, J. 1994. Ancient Murrelet in Devon: New to the Western Palearctic. Br. Birds 87:307-310. Webster, R,, Lehman, R, and Bevier, L. (1980]. The birds of Santa Barbara and Ventura counties, California. Santa Barbara Mus. Nat. Hist. Occasional Paper 10. Wilbur, S. R. 1987. Birds of Baja California. Univ. of Calif. Press, Berkeley. Accepted 18 November 1994 45 NOTES INCUBATION AND BROOD REARING BY A WILD MALE MOUNTAIN QUAIL DAVID J. DELEHANTY, Ecology, Evolution, and Conservation Biology Program, 1000 Valley Road, University of Nevada, Reno, Nevada 89512 The Mountain Quail [Oreortyx pictus ) is among the most poorly known birds of the American west. No comprehensive study of the species’ breeding biology exists (Gutierrez 1975, 1980). This is unfortunate because Mountain Quail populations have declined significantly in Washington (Wash, Dept. Wildlife 1993), Oregon (K. Durbin, Ore. Dept. Fish and Wildlife, pers. comm.), Idaho (T. Hemker, Ida. Dept. Fish and Game, pers. comm.), and Nevada (S. Stiver, Nev. Div. Wildlife, pers. comm.). Information on Mountain Quail reproduction could benefit management efforts. Primary accounts of the Mountain Quail provide little information on male and female roles in reproduction (i.e., Coues 1874, Grinnell et al. 1918, Grinnell and Storer 1924, Bent 1932, Linsdale 1936, Miller and Stebbins 1964, Gutierrez 1975, 1980). Grinnell and Storer (1924:268) stated, “Females, so similar to the males in plumage as not to be distinguishable under normal circumstances, are not in much evidence after the nesting sites have been selected,” suggesting an assumption that primarily females tend nests and eggs. Miller and Stebbins (1964:70) noted that many male Mountain Quail have incubation patches, and they collected one such male associated with a brood of one-third-grown young. Incubation by males has been documented for the California Quail (Callipepla californica ), Scaled Quail (C. squamata) (Johnsgard 1988), and Northern Bobwhite ( Colinus virginianus) (Clark 1903, Curtis et al. 1993). Males of these species also brood young, as do male Gambel’s Quail ( Callipepla gambelii) and Montezuma Quail {Crytonyx monte- zumae) (Johnsgard 1988). Neither incubation nor brooding by male Mountain Quail has been documented, although incubation patches on males imply this possibility (Johnsgard 1973). Here, I report a case of a wild first-year male Mountain Quail successfully incubating a clutch of 13 eggs and subsequently rearing the young unaided by a female. On 2 June 1993, Dave Pratt located and reported to me a Mountain Quail nest containing 6 eggs in second-growth mixed pine forest in Nevada Co., California (39° 26' 35" N, 120° 16' 04" W). On 16 June, I trapped an adult Mountain Quail on the nest while it incubated. I did not count the number of eggs the day the adult was trapped, but I did notice that the nest contained more than 6 eggs. Two days after trapping, the nest contained 13 eggs, which proved to be the complete clutch. I placed a radio transmitter on the quail, took a blood sample for genetic identification of sex, and inspected its plumage. The quail had buffy-tipped greater primary coverts on the upper side of the wing. Also, primaries 9 and 10 were faded and worn relative to primaries 1-8, a pattern typical of first-year quail. Together, these features indicated the bird was a yearling (Johnsgard 1983). Subsequent genetic analysis, following the methods of Longmire et al. (1993) as adapted to Mountain Quail (unpubl. data), indicated that the quail was male. I relocated the quail nine times each during incubation and brood-rearing. Reloca- tion times varied from early morning to dusk, and monitoring periods ranged from 46 Western Birds 26:46-48, 1995 NOTES brief visits to the nest to as many as 10 hours of continuous monitoring. During incubation, I also photographed and observed the quail for extended periods from a blind 3 m from the nest. Two days after capture, the male was off the nest for 10 hours before beginning incubation at dusk. Thereafter, during each relocation, 1 observed the male incubating or, in the early morning, foraging near the nest. Whenever the male was not incubating, I checked the nest for another adult incubating the eggs. I did not observe another quail on or near the nest. The 13 eggs hatched on approximately 14 July, after which 1 regularly relocated the male with chicks. I ended each relocation by flushing the male away from the chicks and listening to the subsequent reassembly of the adult and brood. The male and chicks vocalized back and forth until they were reunited. In no case did an adult quail other than the radio-marked male vocalize to assemble the brood. Only once was another adult Mountain Quail observed near the brood. Twenty-six days after the eggs hatched, an adult Mountain Quail flushed with the radio-marked male approxi- mately 10 m from the brood. The radio-marked male quickly returned to the area and, unlike the second adult, which was not seen or heard again, vocalized and assembled the brood. Twenty-nine days after hatching, I observed 12 or 13 chicks with the radio- marked male. My last observation was made 37 days after hatching, when approximately 12 strongly flying young Mountain Quail flushed with the radio- marked male. Together, these observations imply that a single yearling male Mountain Quail successfully incubated and reared 13 young. Incubation and brood-rearing by males as a regular feature of Mountain Quail reproduction would have strong implications for our understanding of the reproductive and population dynamics of the species. For example, if female Mountain Quail are also able to incubate and rear young alone, which is likely, then “pairs” might be able to rear two broods during one breeding season by employing uniparental care for each brood. This could occur even where the breeding season is too short for two broods to be raised sequentially. Thus, the frequency of uniparental care by Mountain Quail merits further investigation. This research was funded by a grant from the University of Nevada. Thanks are due to V. Boucher, M. Reynolds, and the University of California Sagehen Creek Field Station for logistic support, D. Pratt and D. Davis for help in the field, J. Longmire for laboratory analysis, and S. Baab and M. Rubega for manuscript reviews. LITERATURE CITED Bent, A. C. 1932. Life histories of North American gallinaceous birds. U.S. Natl. Mus. Bull. 162. Clark, J. N. 1903. The domestic affairs of bob-white. Auk 20:161-164. Coues, E. 1874. Birds of the Northwest. Government Printing Office, Washington, D.C. Curtis, P. D., Mueller, B. S., Doerr, P. D., Robinette, C. F., and DeVos, T. 1993. Potential polygamous breeding behavior in Northern Bobwhite, in Quail III: National Quail Symposium (K. E. Church and T. V. Dailey, eds., pp. 1-202) Kansas Dept. Wildlife and Parks, Pratt. Grinnell, J., Bryant, H. C., and Storer, T. I. 1918. The Game Birds of California. Univ. of Calif. Press, Berkeley. Grinnell, J., and Storer, T. 1. 1924. Animal Life in the Yosemite. Univ. of Calif. Press, Berkeley. 47 NOTES Gutierrez, R. J. 1975. Literature review and bibliography of the Mountain Quail (Oreortyx pictus). U.S.D.A. Forest Service, Pacific Southwest Forest and Range Experiment Station, 800 Buchanan St., Albany, CA 94710. Gutierrez, R. J. 1980. Comparative ecology of the Mountain and California Quail in the Carmel Valley, California. Living Bird 18:71-93. Johnsgard, P. A. 1973. Grouse and Quails of North America. Univ. of Nebr. Press, Lincoln. Johnsgard, P. A. 1988. The Quails, Partridges, and Francolins of the World. Univ. of Nebr. Press, Lincoln. Linsdale, J. M. 1936. The birds of Nevada. Pac. Coast Avifauna 23. Longmire, J. L., Maltbie, M., Pavelka, R. W., Smith, L. M., Witte, S. M., Ryder, O. A., Ellsworth, D, L., and Baker, R. J. 1993. Gender identification in birds using microsatellite DNA fingerprint analysis. Auk 110:378-381. Miller, A. H., and Stebbins, R. C. 1964. The Lives of Desert Animals in Joshua Tree National Monument. Univ. Calif. Press, Berkeley. Washington Department of Wildlife. 1993. Distribution status of the Mountain Quail (■ Oreortyx pictus ) in Washington. Wash. Dept. Wildlife, 600 Capital Way North, Olympia, WA 98501. Accepted 23 October 1994 NOTES FIRST UNITED STATES NESTING RECORDS OF THE STREAK-RACKED ORIOLE TROY GORMAN, Arizona Game and Fish Department, 2221 W. Greenway Road, Phoenix, Arizona 85023 GALE MONSON, 8831 North Riviera Drive, Oro Valley, Arizona 85737 In the United States, the Streak-backed Oriole ( Icterus pustulatus) has been reported primarily as a casual fall and winter visitor to southern Arizona and southern California. Its main range extends from the western lowlands of Mexico south to Costa Rica in Central America (American Ornithologists’ Union 1983). In the Mexican state of Sonora it nests in tropical thorn scrub and deciduous forests (especially riparian) north to about latitude 30° N, the northernmost known nest having been found about 175 km south of the international boundary at Felix Gomez (S. Russell and Monson, unpubl. manuscript). On 6 June 1993, Corman observed a dull-plumaged female Streak-backed Oriole carrying nesting material along the San Pedro River near Dudleyville, Pinal County, Arizona. This location is almost 280 km north of the nearest known nest site in Sonora. She was accompanied to a nest by an adult male Streak-backed Oriole (Figure 1). The nest appeared to be less than a week under construction. Only the female worked on the nest. The male joined her there periodically but did not bring material or help with any construction. Monson visited the site on 8 June and located a larger, apparently completed nest approximately 130 m from the nest under construction, without realizing it was not the nest found by Corman. During his visit no activity was discernible at this nest, although an adult male was nearby and a brighter adult female was observed flying past. Corman revisited the nest under construction on 16 and 17 June and spent many hours watching and videotaping the slow progress of nest building. The dull-plumaged female brought pieces of nesting material one at a time, with some of her visits being more than 30 minutes apart. In the early morning and early evening, the male came into the nest tree each time the dull-plumaged female flew in with nesting material. During the late morning and throughout the afternoon, however, he did not appear very often (once in 2 hours was average). Not until his next visit, on 23 June, did Monson discover that he and Corman were watching separate nests. Corman visited both nests on 26 June. There was still no activity at the completed nest, but the dull-plumaged female appeared to have completed the outside of the active nest and was adding lining to the inside. Monson visited both nests on 9 July and saw no activity at the completed nest. The adult male and dull-plumaged female were near the newly finished nest, but neither went into it. Two days later Corman found the dull-plumaged female apparently incubating in her newly completed nest. Surprisingly, when the other nest was checked, the brighter plumaged female was relining the nest with very fine material (Figure 2). She made many trips to the nest during the hour or so it was under surveillance. The adult male also showed up briefly a few times with the brighter female. We revisited both nests intermittently until 4 August. Except on 11 July, the nest completed earlier appeared inactive. The brighter female may have attempted a nesting or brought off a brood before the nest’s discovery on 8 June. The adult male and dull-plumaged female were observed bringing food to the first nest from 20 July through 2 August, the degree of participation by each seemingly being equal. On 30 July, the dull-plumaged female was observed chasing the brighter female from a tree next to the active nest tree. Young could not be seen but were heard begging and their Western Birds 26:49-53, 1995 49 NOTES motion inside the nest was noticeable on several occasions. The possibility that the begging and movement were of a young cowbird ( Molothrus sp.) could not be discounted. On a last visit, on 4 August, neither adult nor young Streak-backed Orioles could be found at or near the nest. We infer that the adult male was paired with both females. The two nests were close enough for him to do this easily, and the birds were not raising young in both nests simultaneously. Polygyny could also explain his long absences during nest construc- tion. The dull-plumaged female was never observed near the nest discovered by Monson, and the brighter adult female was observed only once briefly near the tree with the active nest. Figure 1. Adult male Streak-backed Oriole about to enter nest, with food, near Dudleyville, Pinal Co., Arizona, 17 July 1994. 50 Photo by Troyi Corman NOTES Both nests were large, being approximately 40 to 50 cm long (Figure 3). This is much longer than nests of other western U. S. orioles, which are typically 10 to 16 cm long. Each was supported from the ends of twigs about 8 m above ground in Fremont Cottonwoods ( Populus fremontii) 18 to 20 m tall. Much of the nest material was strips from the lining of dry cottonwood bark with some grasses. The nests were loosely constructed, with some material dangling from adjacent limbs above the nests and from the bottom of the nest structures. The other chief plants in the surrounding riparian woodland were Goodding Willow ( Saiix gooddingii), Seepwillow ( Baccharis salicifolia ), Velvet Mesquite { Prosopis velutina), and Salt Cedar (Tamarix pentandra). Interestingly, three other primarily Mexican species at the northern edge of their known ranges, the Gray Hawk ( Buteo nitidus), Tropical Kingbird ( Tyrannus melancholicus), and Thick-billed Kingbird (Tyrannus crassirostris ), were nesting near (in the same tree in the case of the last) the orioles. These birds returned to the same general location in 1994. This year, however, two separate pairs nested. The nests were farther apart than the previous year, approxi- Figure 2. Adult female Streak-backed Oriole with material to line inside of nest near Dudleyville, Arizona, 11 July 1993. Photo by Troy Corman 51 NOTES mately 220 m. Nesting also appeared to begin a week or more earlier than in 1993. Young were being fed by mid-July in both nests, and on 24 July a fledgling oriole was observed with both parents near one of the nests. Surprisingly, another pair, an adult female and a bird thought to be a first-year male, were found by George Hentz on 9 June 1994. The female of this pair was observed constructing a nest in a bare dead pecan tree near the Santa Cruz River northwest of Marana. Pima County. This nest was extremely long, at 66 cm, and constructed primarily of grasses. The nest was found on the ground on 29 June after high winds the evening before and contained shell fragments from a single egg. The female almost immediately started a new nest on the old nest's limb. She continued working on the nest through 13 July. This nest was shorter than the first (52 cm). On July 16, this nest and the limb attached to it were found hanging from an adjacent tree. The orioles could never be relocated. Little natural-history information is readily available for this species, so we summa- rize our observations in Arizona. The song and chatters of this species are much like Figure 3. Nest of Streak-backed Oriole near Dudleyville, 30 July 1993. Photo by Troy Corman 52 NOTES those of Bullock’s Oriole ( Icterus galbula bullockii/parvus) and were heard primarily near the nest. During the nesting period, a true song given by the male was heard on only a few occasions. Females appeared to sing a partial song, sometimes from the nest. The common call given by both sexes was a low “wrank” reminiscent of the higher “weenk” call of the Hooded Oriole ( Icterus cucullatus). Nest construction is accomplished only by the female and takes approximately 25 days. The site selected is in fairly open situations, under the canopy of the tree, 6 to 8 m above the ground. At all active nests, construction evidently began in early June. The eggs were laid during the last few days of June or in early July, possibly in association with the beginning of the summer “monsoon" season. The female alone incubates. The incubation and nestling periods appear to be much like those of other North American orioles (Bent 1958, Ehrlich et al. 1988), taking approximately 12-14 days for incubation and about 14 days for fledging of the young. Although there may be no direct connection with the nesting individuals near Dudleyville, Monson observed a wintering adult male Streak-backed Oriole at Cook’s Lake, about 6 km south of the oriole nests, on 25 January 1990 [American Birds (AB) 44:305, 1990]. What may have been the same individual was seen subsequently on 5 October 1990 by Gary Rosenberg, David Stejskal, and Chris Benesh [AB 45:137, 1991), on 17 January and 29 March 1991 by Diane Laush (AB 46:298, 1992), on 27 February 1992 by Tom Gatz and Diane Laush (AB 47:286, 1993), on 23 January 1993 by Diane Laush (pers. comm.), and on 13 April 1994 by Monson {Natl. Audubon Soc. Field Notes 48:327, 1994). Yet no Streak-backed Orioles or their obvious nests have ever been found in the immediate Cook’s Lake area during the summer. This first nesting of the Streak-backed Oriole north of Mexico may be related to the changing status of other primarily Mexican species. Within the past 10 years, several, especially riparian species have colonized Arizona. Only time will tell if the oriole will follow the Green Kingfisher (Chloroceryie americana), which has gone from a casual fall and winter visitor in Arizona to a rare breeding resident. The Streak-backed Oriole may parallel other species, such as the Eared Trogon (Euptilotus rieoxenus), Black- capped Gnatcatcher (Polioptila nigriceps), and Rufous-capped Warbler (Basileuterus rufifrons), that occasionally disperse north into Arizona and attempt nesting. Such species appear to persist or return each year, perhaps until eliminated by fire, bad weather, or some such catastrophe. We thank Tom Huels, Dwight Lee, David Stejskal, and especially Deb Treadway for all the time they contributed and effort required in taking notes and watching the progress of the nests. We also thank George Hentz for his surveillance, detailed notes, and photos of the Santa Cruz River pair and Gary Schafer for videotaping nest- building. This note was improved by comments and suggestions from Gary Rosenberg and Philip Unitt. LITERATURE CITED American Ornithologists’ Union. 1983. Check-list of North American birds, 6th ed. Am. Ornithol. Union, Washington, D.C. Bent, A. C. 1958. Life histories of North American blackbirds, orioles, tanagers, and allies. U. S. Natl. Mus, Bull. 211. Ehrlich, P. R., Dobkin, D. S., and Wheye, D. 1988. The Birder’s Handbook: A Field Guide to the Natural History of North American Birds. Simon & Schuster, New York. Accepted 5 December 1994 53 FIFTY YEARS SINCE GRINNELL AND MILLER: WHERE IS CALIFORNIA ORNITHOLOGY HEADED? MICHAEL A. PATTEN, Department of Biology, University of California, Riverside, California 92521 PHILIP UNITT, San Diego Natural History Museum, P. 0. Box 1390, San Diego, California 921 i 2 RICHARD A. ERICKSON, LSA Associates, 1 Park Plaza, Suite 500, Irvine, Califor- nia 92714 KURT F. CAMPBELL, 600 Central Ave., Apt. 118, Riverside, California 92507 December 1994 marked the fiftieth anniversary of a monumental event in California ornithology, publication of The Distribution of the Birds of California by Joseph Grinnell and Alden H. Miller, perhaps the most thorough state avifauna ever produced. Grinnell and Miller laid an impres- sive foundation. Published posthumously (it was completed by Miller), this work was the culmination of nearly fifty years of Grinnell’ s study of California wildlife, an achievement unmatched by anyone. The species accounts are filled with information about centers of abundance, seasonal movements, habitat uses, and outlying records. In terms of habitat descrip- tions, breeding ranges, and subspecies distributions, this work remains the key to our understanding of California’s birds. Its enduring importance is exemplified by the enduring demand for it, enabling Artemisia Press to reprint it in 1986. More recent summaries, such as those by Garrett and Dunn (1981), McCaskie et al. (1988), and Small (1994), have contributed incrementally to our understanding of the status and distribution of California’s birds, but none have reached, let alone exceeded, the level of detail that their forebears attained. For example, Grinnell and Miller’s distribution maps, though forty years older, are still on average more detailed, accurate, and useful than those in Zeiner et al. (1990). As noted by Dunn (1994), “By and large, our knowledge of California breeding birds really hasn’t advanced a lot in most areas beyond what was in Grinnell and Miller.” Whereas this tribute to the authors is a huge one, Grinnell, as noted by Miller (1940), would have been the first to encourage that we move on, using their document as a springboard, and not relying upon it alone forever. Unfortunately, it is all too easy to be complacent about our current state of knowledge. Certainly we have learned a tremendous amount during the past fifty years, but even California, a relatively well-explored state, has many frontiers. Its avifauna, like that anywhere, is not constant. From its inception through the 1950s, the Condor was the primary means of communication about these topics for California birds. As the Condor began to focus more on other issues in avian ecology and behavior, at the expense of distributional and taxonomic notes, a publication void had developed by the late 1960s. Fortunately, California Birds arrived in the nick of time, so that nary a beat was missed in the publishing of basic descriptions of bird distributions. In 1973, the fledgling California Field Ornithologists expanded into the Western Field Ornithologists; this organi- zation has just celebrated its 25th anniversary, and its journal, Western Western Birds 26:54-64, 1995 54 CALIFORNIA ORNITHOLOGY Birds, has grown to become the means of exchange of basic field ornithol- ogy ideas and information throughout western North America. Regional reports in American Birds, now National Audubon Society Field Notes, continue to be a valuable, though narrowly focused, source of primary distributional information. THE QUEST FOR VAGRANTS So what strides have we made in the past fifty years? Without question, our knowledge of the occurrence of vagrants has increased dramatically (“vagrants” being defined as “out-of-range,” after DeSante and Ainley 1980:84). An oft-quoted remark by Grinnell (1922) is that “It is only a matter of time theoretically until the list of California birds will be identical with that for North America as a whole.” By 1970, the quest for vagrants was a hot trend, and largely remains so today. This intrinsically exciting and entertaining pursuit has real scientific value: the status and patterns of occurrence of vagrants often provide insight into large-scale bird move- ments. But as a result of birding’s preoccupation with glamorous vagrants, our knowledge of their status and distribution in California has leapfrogged over that of many regularly occurring breeders, migrants, and wintering species, with Grinnell and Miller still providing the core of our current knowledge for non-vagrants. Grinnell and Miller treated 427 species. By the end of 1979, the California state list had grown to 535 species, an increase of 25% (Jehl 1980). The state list now stands at 586 (Heindel and Garrett 1995), a 10% increase since 1979 and a nearly 37% increase since Grinnell and Miller. With the exception of a few procellariids, particularly Murphy’s {Pterodroma ultima ) and Cook’s (P. cookii) petrels, which have proven to be regular parts of our avifauna and probably always were, and roughly ten species that have truly invaded, such as the Cattle Egret ( Bubulcus ibis) and Great-tailed Grackle ( Quiscalus mexicanus), nearly every species added to the California list since Grinnell and Miller has been a vagrant (see Jehl 1980: Table 1). Species continue to be added annually, and a few invaders may establish themselves, but the ocean far offshore probably represents the only true frontier where we are likely to add species other than vagrants. Yet aside from this impressive increase in the list of species recorded in California, which included, admittedly, a ground-breaking understanding of vagrancy in western North America, our current position in understanding of status and distribution is only marginally ahead of where Grinnell and Miller left us. THE CONSULTING INDUSTRY Another major factor driving California ornithology has been environ- mental regulations, such as the federal Endangered Species Act and the California Environmental Quality Act. The requiring of environmental reports has drawn vastly increased numbers of biologists into the field and prompted the gathering of vast amounts of new data. In particular, the 55 CALIFORNIA ORNITHOLOGY federal Endangered Species Act, because of its role as one of the most effective tools for conservation of birds and their habitats, has resulted in endangered species attracting intensive study and, in some cases, substan- tial money. Knowledge of their distribution and biology has thus often increased disproportionately over that of more common species. Witness, for example, the extensive efforts focused on gathering basic data for the California Gnatcatcher ( Polioptila californica), recently listed as threat- ened by the United States Fish and Wildlife Service. Over the past fifteen years, this species has gone from as obscure as any, even incorrectly classified as a subspecies, to one of California’s best known birds. At this point we probably know more about the California Gnatcatcher than 90% of the other bird species in the state! The status review by Atwood (1990) provided the basis supporting the petition to list the this species as endan- gered. This review was able to include substantial information about current population levels, trends, habitat use, breeding biology, and taxonomy, making it probably the most thorough such documentation ever written. Nevertheless, the listing was recently successfully challenged in court (this ruling was stayed, pending review of additional information). Unfortunately, most current information regarding the biology of the California Gnatcatcher, and a host of other sensitive species, exists only in unpublished documents, in-house reports, or other forms of “gray litera- ture.” This situation arises from the nature of the biological consulting industry, which has grown exponentially as environmental regulations have directed more businesses, developers, and government agencies into bio- logical research. Yet almost none of the information generated by this industry is shared with other biologists. Indeed, much of it is considered proprietary to the business that commissioned the study! Although this problem is not confined to ornithology (c/. Wilbur 1990, Germano and Bury 1994), it has perhaps reached its pinnacle in this field, if only because of the sheer volume of consulting work being performed on birds in this state. Without question, more data about California birds is now being generated than at any time in the state’s history. We acknowledge that many consultant reports are prepared only to assist regulatory agencies in judging compliance with environmental laws, but many contain new, well- documented information describing the basic biology of various California birds. The ultimate culprit is the short-sightedness of the environmental review process, which pays for the gathering of information, and for the writing of reports that gather dust in bureaucrats’ files, but not for dissemi- nating this information to the scientific community. Every effort should be made to share such data and, if appropriate, to publish them in peer- reviewed outlets such as Western Birds. Failure to share requires all of us to continually reinvent the wheel, escalating costs. Researchers in the bur- geoning field of conservation biology desperately need good field data and solid descriptive ornithology, not the political strife so often associated with conservation efforts, such as the recent lawsuits associated with the Califor- nia Gnatcatcher and Northern Spotted Owl ( Strix occidentalis caurina ) listings. As noted by Dhondt and Matthysen (1993), “urgent answers that conservation biology needs cannot often be provided by our present knowl- edge [and] although birds are better known than any other animal group, for 56 CALIFORNIA ORNITHOLOGY many species we have only vague ideas about their actual ranges and basic life-history traits.” LEVELS OF SCALE Effective conservation planning at the local level requires a very fine-scale knowledge of bird distribution and abundance. Yet this kind of information is lacking except for a few endangered species and colonial seabirds (Sowls et al. 1980). For the great majority of California birds, the most detailed distributional data for the state as a whole are still the maps and text in Grinnell and Miller. Accurate as they are, their focus is at too coarse a scale for many of today’s needs. The several county- or region-specific avifaunas published over the past twenty-five years (e.g., Harris 1991, Lehman 1994, Unitt 1984) for the most part update Grinnell and Miller adequately for those areas, but none achieves a significantly finer focus of scale. The first real breakthrough beyond this level has come only in the past two years with the publication of California’s first two breeding bird atlases (Roberson and Tenney 1993, Shuford 1993). Several other similar projects are in varying stages of progress (Manolis 1991). Each of these atlases has been initiated and pursued by private organiza- tions and individuals, mainly amateurs, with no significant direction or support from government agencies. Yet, for the areas covered, these atlases will likely prove more useful to the wildlife agencies than anything the agencies have produced or sponsored themselves. If a tenth of the millions of dollars spent for consultants’ studies had gone to support bird atlases as well executed as those for Marin and Monterey counties, we would have California’s avifauna mapped completely, in even more exquis- ite detail, and a solid base for multiple-species conservation plans through- out the state. Instead, we endure the spectacle of millions being wasted on unpublished studies whose only visible result is political deadlock. The state of California has made a significant step toward useful management of information with the establishment of the Department of Fish and Game’s Natural Diversity Data Base (Shaw 1987), but this data base is still very incomplete, even for the sensitive species it covers, and will remain so as long as its cost for use remains exorbitant. Other projects, such as the Urban and Environmental Outreach Program at the University of Califor- nia, Riverside (intended to provide consultants and researchers with litera- ture searches from published and unpublished sources), show promise of solving this information-management problem on a local level, but they have yet to become operational. THEORETICAL VS. APPLIED ORNITHOLOGY If descriptive ornithology and wildlife management have diverged, de- spite their natural interdependence, descriptive and theoretical, often uni- versity-based, ornithology have diverged even further (see Auk 97:409 and 98:636). With advances in the science and technology of avian ethology, ecology, energetics, physiology, genetics, etc., descriptive ornithology (the search for patterns ) ceased to be at the “cutting edge,” even though much 57 CALIFORNIA ORNITHOLOGY of it remains to be done. Universities began directing students into “cutting- edge,” theoretical research (the search for processes) and away from descriptive ornithology. Ultimately descriptive ornithology, especially local faunistics, was left unsuitable as a thesis topic for graduate students in biology. All too frequently now, university-trained ornithologists have no ability or interest in identifying birds. It is as if physics students, after the development of relativity theory and quantum mechanics, no longer learned Newtonian mechanics. Thus orphaned, descriptive ornithology was inher- ited by birders, who have a natural interest in cultivating it. Meanwhile, academic ornithology forged ahead, using mathematical and physical tools not readily accessible to amateurs. Ornithology thus followed the path of so many other sciences, in which ground-breaking advances can now be made only with the aid of sophisticated theories, expensive instru- mentation, and money. Yet the need for more and better information on bird identification and distribution remains, along with those of us who feel motivated to explore these topics. One point where the divergence between theoretical, process-oriented and descriptive, pattern-oriented ornithology is about to become a rift is over the definition of species. Genetic studies are beginning to suggest that some populations are reproductively isolated even though they are not completely differentiated in either external appearance or by voice. Johnson (1994) is quite right to point out that birds bear no responsibility for making themselves easy to identify. But field work in ecology, biogeography, and the like demands a species concept that is not only biologically sound but broadly useful as well. A proliferation of species cryptic to anyone outside a genetics lab would disrupt ornithology pursued anywhere else. We do not doubt that such cryptic “species” may be real, may merit study, and may have useful applications, but we prefer they be known by some other name. Otherwise, we see the biggest upheaval in systematics since Darwin, and the rift in ornithology becoming as great as that between quantum mechan- ics and home remodeling. A related trend is the promotion of the “phylogenetic species concept” (Cracraft 1983, McKitrick and Zink 1988), in which every minimally diagnosable cluster of individuals considered an independently evolving unit is ranked as a species. This notion seems equally destructive to applied ornithology, its theoretical validity aside. We question the usefulness of a concept that assumes that speciation proceeds uniformly by the dichoto- mous branching of lineages, when evidence of their anastomosing in a network (secondary intergradation) is manifest. THE VALUE OF SUBSPECIES Perhaps in nothing is the divergence between process-oriented and pattern-oriented ornithology more marked than in the use of subspecies. New genetic techniques have revealed that the difference between two subspecies is reflected in but a tiny fraction of their genome, a fraction often different from the tiny fraction examined in genetic studies. These studies have often implied a population structure and evolutionary history different from what might have been inferred from subspecies defined by differences 58 CALIFORNIA ORNITHOLOGY in external appearance. Therefore many ornithologists have rejected the use of subspecies or at least neglected them as irrelevant. The viewpoints presented in a forum on the subspecies concept (Wiens 1982) illustrate this trend well (see also Monk 1992, Zink 1994, and Frank A, Pitelka’s comments in the 1986 Artemisia Press reissue of Grinnell and Miller 1944). Part of the recent disdain for subspecific taxonomy may be traceable to misunderstanding just what a subspecies is. Many believe that described subspecies have utility only if they represent “evolutionary units” or incipi- ent species. But as Mayr (1942:155) wrote in addressing the relationship between species and subspecies, “Geographic speciation is thinkable only if subspecies are incipient species. This, of course, does not mean that every subspecies will eventually develop into a good species. Far from it! All this statement implies is that every species that developed through geographic speciation had to pass through a subspecies stage.” Subspecies remain essential to the most detailed understanding of bird distribution and migration. They constitute the finest level on which most persons interested in birds will ever be able to describe them and their distributions. Marshall (in Phillips et al. 1964:x) put it well when he noted that “subspecies teach us more about migration than any other source of information . . . [and] constitute whole populations which are ‘marked’ by their peculiarities of color, size and proportions.” Even the American Ornithologists’ Union, in its Check-list of North American Birds, the source followed as a standard for taxonomy in most publications on this continent, seems to have abandoned subspecies, de- spite its fine explanation for their maintenance (A.O.LI. 1983:xiii). Not for thirty-eight years (A.O.U. 1957) has it dealt with subspecific taxonomy or distribution, and most of the current members of the check-list committee have published little or nothing on the subspecies of North American birds. Although it was not the intent of the A.O.U. to leave subspecies out of its check-list forever (Lanyon 1982), as this neglect continues, many field ornithologists and birders mistakenly conclude that subspecific information is of no value. Worse yet, the omission of subspecies from the sixth edition of the A.O.U. Check-list is frequently misinterpreted. For example, in their Field Sparrow ( Spizella pusilla) account, Carey et al. (1994) stated that there are “No currently recognized subspecies (Am. Ornithol. Union 1983)”! Despite such misconceptions, S. p. arenacea remains strongly differentiated. With few exceptions (e.g., Johnson and Marten 1992), as a result of this long neglect, understanding of California subspecies has advanced little since the time of Grinnell and Miller. The preoccupation of some of the old- time collectors with this subject may lead some to assume that little remains to be learned about it. Since 1957, however, some twenty new subspecies of birds occurring in California have been described (Browning 1990, Phillips 1991), though the validity and precise ranges of some of these need to be tested and refined. Doubtless some subspecies remain to be described, even in California; the avian biodiversity in our vast state has still not been fully documented. Data about the distribution and status of many, if not most, subspecies remain poor. For example, the literature indicates that only one subspecies 59 CALIFORNIA ORNITHOLOGY of the Black-capped Chickadee ( Parus atricapillus) occurs in California: P a. occidentalism as a resident in cismontane lowlands south to Humboldt County and inland to Siskiyou County, with only limited winter movements (A.O.U. 1957, Erickson pers. obs.). Yet E. Clarke Bloom (unpubl. data) has recorded Black-capped Chickadees in winter on the Modoc Plateau. Rather than P. a. occidentalism which many might assume they are, these birds could be P, a, fortuitus, a subspecies with documented winter dispersal in other regions, or even the presumably sedentary but geographically closer P. a. neuadensis; neither of these subspecies is known from California, and both differ conspicuously from occidentalis. Vagrants can originate from multiple source populations (McCaskie and Patten 1994). For example, the majority of the Yellow-throated Warblers C Dendroica dominica ) recorded in California have been of the “white- lored,” small-billed subspecies albilora, but there are at least four well- supported occurrences (e.g., Craig 1970) of large-billed, yellow-lored birds, presumably nominate dominica. Unfortunately, this species is one of the few for which such information is available, for the commendable effort made to document vagrants too often stops at the species level. Whereas many vagrants have proven regular in California, these are of species lacking subspecies common in California. That eastern subspecies of transcontinental species are lacking from the California list is nearly as true as twenty years ago, when Phillips (1975) joked that “eastern birds appear to stray west only if they lack western relatives.” He mentioned specifically the eastern Hermit ( Catharus guttatus) and Swainson’s (C. ustulatus) thrushes, Bell’s ( Vireo bellii ), Solitary ( V. solitarius), and War- bling vireos (V. gilvus), and Nashville ( Vermivora ruficapilla), Yellow { Dendroica petechia), and Wilson’s warblers ( Wilsonia pusllla). Twenty years later, of these subspecies, only the nominate subspecies of the Solitary Vireo has been collected in California (once); for the others there are only a few inconclusive unpublished sight reports. CONSERVE THE COLLECTIONS Answering these sorts of questions requires judicious collecting of speci- mens. Collecting (and even mist-netting), however, has unfortunately fallen into disfavor in many birding circles, despite many excellent commentaries explaining the critical need for specimens and collections, including one by Grinnell himself eighty years ago (Grinnell 1915). Mercifully, in California bird collecting is not regulated as excessively and counterproductively as it is in some states, but urbanization and the need for special local authoriza- tions make it impractical over ever larger areas. Still, collecting and collec- tions need the wholehearted support of birders (Winker et al. 1991). If the practitioners and consumers of applied, descriptive ornithology do not support collections, they cannot expect the ecologists, physiologists, and geneticists to do it for them. The recession of the 1990s has led to the financial hobbling of several of California’s important bird collections. If these are to remain open for public use, birders and field biologists must make responsibility for their maintenance and prosperity a priority for their parent institutions. 60 CALIFORNIA ORNITHOLOGY Collections and descriptive taxonomy are crucial not only to basic orni- thology but to many conservation efforts as well. As noted by Zink (1994), “Museums, and associated personnel trained in identification of specimens, taxonomy, and phylogenetic relationships, must form the framework of our attempt to preserve the earth’s biota. ” So whether or not subspecies are in fashion, we must keep in mind that birds distribute themselves by popula- tions, not by species; they are also most effectively conserved, or lost forever, at the population level. The California Gnatcatcher is just one example of taxonomy’s bearing on conservation. Many other rare or endangered taxa need taxonomic reevaluation. For example, the Eagle Mountain Scrub Jay ( Aphelocoma coerulescens cana ) and Inyo Brown Towhee ( Pipilo crissalis eremophilus) may not be valid subspecies (Phillips 1986, Peterson 1990, Unitt pers. obs.). Conversely, the recently described and intensively analyzed San Diego Cactus Wren ( Campylorhynchus brun- neicapillus sandiegensis), though rarer than California Gnatcatcher (Rea and Weaver 1990), will receive no protection from the U. S. Fish and Wildlife Service (1994). This agency denied the subspecies’ existence by pretending the published study did not exist and relying on one of its own employees for scientific cover. Subspecies distributions are no less static that those of species. For example, the San Diego Song Sparrow ( Melospiza melodia coopen ) has invaded the range of the desert subspecies M. m. saltonis, and secondary intergradation of two of the most divergent subspecies in North America has begun (Unitt pers. obs.). Do the Loggerhead Shrikes of San Clemente Island, still represent Lanius ludovicianus mearnst, a subspecies listed as endangered? Our observations suggest that, externally, they may not. What does this mean for the conservation of the population? Even without collecting one can contribute to our understanding of subspecies distribution. The Atlantic Brant (Branta bernxcla hrota), Myrtle Warbler ( Dendroica coronata), and Harlan’s Hawk (Buteo jamaicertsis hariani), are as readily field-identifiable as they were when they were ranked as species, though reports of them are spotty or have virtually ceased (Patten and Campbell 1992). CONCLUSION Grinnell and Miller provided us with a sturdy foundation for the study of bird species and subspecies in California. Now more than ever, given the massive and rapid changes in this state’s environment, we need to update and refine our knowledge in all fields to build upon that foundation. Unanswered questions remain at all levels. Why has the Brown Pelican (Pelecanus occidentalis) increased so dramatically as a post-breeding visi- tor to the Salton Sea? Why do we almost never detect migrant Black- chinned Sparrows (Spizella atrogularis )? Is the Least Bittern (Ixobrychus exilis ) declining in California? Basic knowledge of breeding biology, dis- persal capabilities, and habitat requirements is still needed for most species, let alone populations. Most counties still need an updated summary, much less a breeding bird atlas. An atlas of winter distribution, as has been done for Britain and France, for example, is still beyond the horizon. As clear as 61 CALIFORNIA ORNITHOLOGY the importance of descriptive ornithology may seem to those of us in the field, it will be an uphill battle to educate and reeducate society about its relevance and applications. Finding resources to support its practice and communication will be an even greater challenge. Fortunately, Western Birds remains committed to the importance, practice, and publication of descriptive ornithology in the tradition of Grinnell and Miller. ACKNOWLEDGMENTS We are indebted to Matthew T. Heindel, Robert A. Hamilton, and Amadeo M. Rea for many valuable discussions about the issues covered in this commentary. We thank Mary K. Chase, Robert A. Hamilton, Art Homrighausen, Pey-yi Lee, Jamie Rotenberg, John T. Rotenberry, Brenda D. Smith, and Scott D. White for providing useful comments on various drafts and for their helpful perspectives. UTERATURE CITED American Ornithologists’ Union. 1957. Check-list of North American Birds, 5th ed. Am. Ornithol. Union, Baltimore. Atwood, J. L. 1990. Status review of the California Gnatcatcher ( Polioptila coiifornica). Manomet Bird Observatory, P. O. Box 1770, Manomet, MA 02345. Browning, M. R. 1990. Taxa of North American birds described from 1957 to 1987. Proc. Biol. Soc. Washington 103:432-451. 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California [Christmas Bird Count sum- mary]. Am. Birds 47:1042-1044. Peterson, A. T. 1990. Birds of Eagle Mountain, Joshua Tree National Monument, California. W. Birds 21:127-135. Phillips, A. R. 1975. Why neglect the difficult? W. Birds 6:69-86. Phillips, A. R. 1986. The Known Birds of North and Middle America, Part I. A. R. Phillips, Denver. Phillips, A. R. 1991. The Known Birds of North and Middle America, Part II. A. R. Phillips, Denver. Phillips A., Marshall, J., and Monson, G. 1964. The Birds of Arizona. Univ. of Ariz. Press, Tucson. Rea, A. M., and Weaver, K. L. 1990. The taxonomy, distribution, and status of coastal California Cactus Wrens. W. Birds 21:81-126. Roberson, D., and Tenney, C., eds. 1993. Atlas of the Breeding Birds of Monterey County. Monterey Peninsula Audubon Soc., Carmel, CA. Shaw, C. A. 1987. The California Natural Diversity Data Base and riparian ecosys- tem conservation. W. Birds 18:85-88. Shuford, W. D. 1993. The Marin County Breeding Bird Atlas. Bushtit Books, Bolinas, CA. Small, A. 1994. California Birds: Their Status and Distribution. Ibis, Vista, CA. Sowls, A. L., DeGange, A. R., Nelson, J. W., and Lester, G. S. 1980. Catalog of California seabird colonies. U. S. Fish Wildlife Serv. OBS-80/37. 63 CALIFORNIA ORNITHOLOGY United States Fish and Wildlife Service. 1994. Endangered and threatened wildlife and plants; 1-year finding for a petition to list the Pacific Coast population of the Cactus Wren under the Endangered Species Act. Federal Register 59:45659- 45661. Unitt, P. 1984. The birds of San Diego County. San Diego Soc. Nat, Hist. Memoir 13. Wiens, J. A., ed. 1982. Forum: Avian subspecies in the 1980’s. Auk 99:593-615. Wilbur, R. L. 1990. Gray literature: A professional dilemma. Fisheries 15:2-6. Winker, K. W,, Fall, B. A., Klicka, J. T., Parmelee, D. F., and Tordoff, H. B. 1991. The importance of avian collections and the need for continued collecting. Loon 63:238-246. Zeiner, D. C., Laudenslayer, W. F., Jr., Mayer. K. E., and White, M. 1990. California’s Wildlife, vol. II: Birds. Calif. Dept. Fish and Game, Sacramento. Zink, R. M. 1994. Review [Avian Systematics and Taxonomy]. Wilson Bull. 106:575-577. Accepted 1 December 1994 Yellow-billed Magpie Sketch by Tim Manolis WESTERN BIRDS Quarterly Journal of Western Field Ornithologists President: Robert McKeman, 1230 Friar Lane, Redlands, CA 92373 Vice-President: Steve Summers, P.O. Box 202, Silver Lake, OR 97638 Treasurer/Membership Secretary: Dorothy Myers, 6011 Saddletree Lane, Yorba Linda, CA 92686 Recording Secretary: Jean-Marie Spoelman, 4629 Diaz Drive, Fremont, CA 94536 Circulation Manager: Mamie S. Crook, P.O. Box 10483, San Bernardino, CA 92423 Directors: Bruce Deuel, Kimball Garrett, Peter Gent, Guy McCaskie, Robert McKeman, Steve Summers, Bill Tweit, Janet Witzeman, David Yee Editor: Philip Unitt, 3411 Felton Street, San Diego, CA 92104 Associate Editors: Cameron Barrows, Tim Manolis, Thomas W. Keeney Graphics Manager: Virginia P. 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Pelagic Birds of Monterey Bay, California: $2.50 each, 10 or more $2.00 each, 40 or more $1.50 each. All postpaid. Published January 15, 1995 ISSN 0045-3897 VoL 26, No. 2, 1995 Volume 26, Number 2, 1995 Bird Observations on Wake Atoll H. Lee Jones 65 Sex Ratios and Bill Growth in Nestling Black-chinned Hummingbirds Elizabeth P. Elliston and William H. Baltosser 76 Distribution and Abundance of Snowy Plovers Wintering in the Interior of California and Adjacent States W. David Shuford, Gary W . Page, and Catherine M. Hickey 82 NOTES Breeding Birds of Esteros Tdbari and San Jose, Southern Sonora Eduardo Palacios and Eric Mellink 99 Cassins Sparrow Nesting in Wyoming Robert D. Dorn and Jane L. Dorn 104 House Wrens Feeding Fish to Their Nestlings Tara Y. Williams and David S. Pennock 107 Commentary Tim Manolis 109 President’s Message Robert McKernan 110 Corrigendum Richard A. Erickson and Michael A. Patten .... 112 Cover photo by © Herbert Clarke of Glendale, California: Mountain Quail (Oreortyx pictus), Yosemite National Park, California, August, 1989. Western Birds solicits papers that are both useful to and understandable by amateur field ornithologists and also contribute significantly to scientific literature. The journal welcomes contributions from both professionals and amateurs. Appropriate topics include distribution, migration, status, identification, geographic variation, conservation, behavior, ecology, popula- tion dynamics, habitat requirements, the effects of pollution, and techniques for censusing, sound recording, and photographing birds in the field. Papers of general interest will be considered regardless of their geographic origin, but particularly desired are reports of studies done in or bearing on the Rocky Mountain and Pacific states and provinces, including Alaska and Hawaii, western Texas, northwestern Mexico, and the northeastern Pacific Ocean. Send manuscripts to Philip Unitt, 3411 Felton Street, San Diego, CA 92104. For matter of style consult the Suggestions to Contributors to Western Birds (8 pages available at no cost from the editor) and the Council of Biology Editors Style Manual (available for $24 from the Council of Biology Editors, Inc., 9650 Rockville Pike, Bethesda, MD 20814). Reprints can be ordered at author’s expense from the Editor when proof is returned or earlier. Good photographs of rare and unusual birds, unaccompanied by an article but with caption including species, date, locality and other pertinent information, are wanted for publication in Western Birds. Submit photos and captions to Photo Editor. Also needed are black and white pen and ink drawings of western birds. Please send these, with captions, to Graphics Manager. WESTERN BIRDS Volume 26, Number 2, 1995 BIRD OBSERVATIONS ON WAKE ATOLL H, LEE JONES, 6108 Wildwood Road, Lake Isabella, California 93240 Wake Atoll, at 19° 18' N, 166° 38' E, is one of the earth’s most isolated land masses. It is 1700 mi. (2700 km) from Japan and 2000 mi. (3100 km) from Honolulu. The nearest point of land is tiny Taongi Atoll in the northern Marshall Islands, 350 mi (550 km) to the southeast. As this island is seldom visited by ornithologists, its avifauna is little known. Wake Atoll, usually referred to as Wake Island, consists of three islets, only one of which is correctly called Wake Island. The atoll is V-shaped with its apex projecting southeast. Its total land mass is only 3 mi 2 . Each arm of the "V" is approximately 4.5 mi. (7.0 km) long and averages about 0.3 mi. (0.5 km) across, with a shallow lagoon between the arms. Both arms are broken near their distal end. Wilkes Island, at the tip of the south arm, was once separated from the main island by about 300 feet (100 m) but is now connected by a causeway. At the tip of the north arm is slightly larger Peale Island, separated by a 400-foot (125-rn) channel traversed by a narrow bridge. Seabird colonies are almost restricted to these two islands. Most human activity and virtually all permanent buildings are confined to the main island. The birds of Wake Atoll are known from only a few accounts: Vaughn (1945), Bailey (1951), Bryan (1959), Rice and Kenyon (1962), Casey (1966), Fosberg (1966), Johnston and McFarlane (1967), Rowland (1990), and Sutterfield (1990), plus unpublished reports and field notes of the Pacific Ocean Biological Survey Program in the National Museum of Natural History, Washington, D.C. Pratt et al. (1987) summarized the known avifauna through about 1985. I visited the island from 24 March until 1 April 1993 as the ornithologist for a biological survey conducted for an “environmental assessment for long-term activities at Wake Atoll” (U. S. Army Space and Strategic Defense Command). I found most of the species reported by previous investigators. The Red-tailed Tropicbird [Phaethon rubricauda ), Brown Booby ( Suia leucogaster), Red-footed Booby ( Sula sula), Sooty Tern ( Sterna fuscata), and Brown Noddy ( Anous stolidus) were breeding at the time of my visit. Three other species present but Western Birds 26:65-75, 1995 65 BIRDS OF WAKE ATOLL apparently not breeding at the time of my visit were the White-tailed Tropicbird ( Phaethon lepturus ), Masked Booby ( Sula dactylatra), and Great Frigatebird ( Fregata minor), SPECIES ACCOUNTS The following species accounts include, in addition to my observations, accounts of the birds observed and photographed by Lou Hitchcock, a civilian Air Force employee and 20-year resident of the island, Hitchcock is not an ornithologist and has had no access to field guides or experts, but he has documented much of what he has observed of the plants and wildlife over the years with an excellent series of photographs that I examined. Historically, no land-dependent birds other than shorebirds, ducks, and the now-extinct Wake Rail ( Rallus wakensis) were documented from this remote atoll. Laysan Albatross Diomedea immutabilis. This species breeds in the northwestern Hawaiian Islands and the Ogasawara (Bonin) Islands south of Japan, and may be establishing small colonies on Guadalupe Island and San Benedicto Island off the west coast of Mexico (Harrison 1990). It ranges at sea throughout the northern Pacific Ocean (Sanger 1974). It was formerly more common and widespread and may have bred on Wake Atoll. In Hawaii it nests during the winter (Harrison 1990), but in what season it has nested or attempted to nest on Wake Atoll is not clear. Hitchcock frequently has seen up to four or five birds at a time on the island. He reports that they stay for a few weeks at a time but never nest successfully. They keep to the closely cropped grassy areas adjacent to the runway, where they lay their eggs. Hitchcock has never seen young and believes the feral cats, and possibly rats, may destroy the hatchlings. He has excellent photographs of paired birds in courtship (Figure 1). I did not see this species during my visit. Titian Peale, artist and naturalist on the LJnited States Exploring Expedition in 1841, found “short-tailed albatrosses” here, which may have been this species, as well as the Black-footed (Rice and Kenyon 1962). Peale referred to them as D. brachyura, believing the different plumages were different age classes of the Short- tailed Albatross. The one specimen from this expedition in the U. S. National Museum is nigripes, but an egg collected appears to be that of immutabilis (Rice and Kenyon 1962). Rice and Kenyon (1962) also reported Alexander Wetmore’s recollections from his 1923 Tanager Expedition to Wake Atoll. Wetmore told them of great destruction of birds by the Japanese in the years prior to his visit from 27 July to 7 August 1923. He found evidence of a recently operated skinning plant, indicative of extensive plume hunting on the island, that contained piles of bones from frigatebirds, boobies, and terns, but no albatrosses. He surmised that the lack of albatross bones suggested that they no longer bred on the island by 1923 and perhaps long before. Rice and Kenyon also stated, “Information supplied by several observers who were on Wake from 1935 until the Japanese occupation in 1942 confirmed the absence of albatrosses on the island during this period.” Rowland (1990), however, mentioned a 1936 photograph of the old Pan Ameri- can hotel in the Wake Island Museum that shows an adult Laysan Albatross and several downy chicks on the lawn. He also mentioned a possible Laysan Albatross nest in 1988 reported to him by island residents in 1989. Furthermore, Bailey (1951) also suggested that some species of albatross bred on the island during the period of Japanese occupation in World War II. An American blockade of the island had all but cut off the Japanese from their supply lines, resulting in the starvation of 66 BIRDS OF WAKE ATOLL many of the troops during the last few months of their occupation. He quotes from the diary of a Japanese officer stationed on the island at that time: “An order has just come out forbidding us to catch gooney birds [albatrosses] lest they be wiped out.” It appears from these accounts that Laysan Albatrosses have bred or attempted to breed periodically on Wake Atoll since the earliest visits by ornithologists in the last century. Unfortunately, little concrete evidence exists to support these observations. Black-footed Albatross Diomedea nigripes. I saw two flying together about 2 km off Peacock Point on 25 March and observed one flying low over the airstrip on 31 March. Gary Lumia. an Air Force maintenance technician, described to me six large all-dark “gooney birds" he had seen regularly at Peacock Point for a period of time until about “four weeks ago." He thought they might be nesting because of their courtship activities but never saw eggs or young. Black-footed Albatrosses have bred on Taongi Atoll (Pratt et al. 1987). the land nearest Wake, but have not been definitely observed breeding at Wake Atoll since Peale's visit in 1841. White-tailed Tropicbird Phaethon lepturus. I briefly saw one adult in flight near the rain catchment basins between the personnel housing area and the air terminal on 25 March. Hitchcock sees them every year and believes that a few breed. Fosberg (1966) reported one near Flipper Point in September 1961 and two on Wilkes Island on 8 March 1963. Casey (1966) reported two adults with one chick in the rubble of an old Japanese blockhouse on the island during her visit in 1966 (specific date not given). This species breeds primarily on high islands, in trees in the interior or in shaded rock crevices along coastal headlands, but also nests in small numbers on low- lying atolls such as at Midway Island (Harrison 1990). Figure 1. Laysan Albatross courting, Wake Atoll. Photo by Lou Hitchcock 67 BIRDS OF WAKE ATOLL Red-tailed Tropicbird Phaethon rubricauda. Unlike the White-tailed Tropicbird, this species breeds primarily on atolls and other low-lying islands (Figure 2). Its numbers increased noticeably during the eight days I was on the atoll, suggesting that it was in the earliest stages of its breeding cycle. In all, I found ten birds on nests and observed courtship activity in several other areas, suggesting additional unseen or not-yet-established nest sites. Nesting and courting birds were in six more or less distinct areas on Peale Island and Wake Island proper northwest of the air terminal, but not on the southern arm of the atoll. Of three attended nests examined, one contained an egg and two were empty. According to Gould et al. (1974), this species breeds mainly from March through July or August on Wake Island. Masked Booby Sula dactylatra. I saw three adults in the Brown Booby colony and these or other individuals on nearby offshore rocks at the west end of Wilkes Island. No nests, eggs, or young were observed. These birds may have been in the early stages of breeding (before egg laying). Apparently, this species breeds on Wake only in small numbers. Other accounts have reported fewer than six pairs. Fosberg (1966) saw only a very few on Peale Island on 22 and 23 October 1953. Casey (1966) stated that it is “rarely seen.” Rowland (1990) saw only two active nests, both with chicks, on Wilkes Island in 1989. Sutterfield (1990) saw two Masked Boobies on eggs in late October 1989. Brown Booby Sula leucogaster. I located two adjacent colonies of approximately 30 and 26 nests on the outer perimeter of the Wilkes Island Sooty Tern colony. Young were in all stages of growth from recently hatched to nearly full-sized downy with moderately developed flight feathers. No nest contained more than two young, and all nests with well-developed young had only one. I saw no eggs, but several Figure 2. Nestling Red-tailed Tropicbird, Wake Atoll. 68 Photo by Lou Hitchcock BIRDS OF WAKE ATOLL sitting birds may have been incubating, Fosberg (1966) found it to be the most common of the boobies. He found 20 pairs, all with young, on the lagoon side of Kuku Point, Wilkes Island. Rowland (1990) counted 106 nests, most with young, on Wilkes Island in April 1989. Sutterfield (1990) found 148 Brown Boobies beginning nest construction and two on eggs in late October 1989. Red-footed Booby Sula sula. I found two small adjacent colonies in Beach Heliotrope (Tournefortia argentea) and Naupaka (Scaevola sericea ) trees near the west end of Wilkes Island. These two colonies were approximately 100 m apart at the interface between heliotrope scrub forest and the large grassy field (the Vortac area) at the island’s west end. The nests were between 1.5 and 4 m off the ground. Approximately one third of the nests held nestlings; the other nests may have contained eggs or recently hatched young. No young were more than two-thirds grown. Approximately 26 nests were visible from the field and about nine others were seen as far as about 15 m into the scrub forest. Bailey (1951) saw no boobies of any species nesting on the island when he visited in May 1949, and attributed this to the near devastation of the island during the war, which had ended four years earlier. Fosberg (1966) found a few nesting on Peale Island on 21 April 1952. Rowland (1990) counted 41 Red footed Booby nests on Wilkes Island in April 1989. The eight nests in which he was able to determine the contents all had young. Most Red-footed Boobies on Wake Atoll are light-morph birds; however, at least two I saw were white-tailed brown morphs. One of these was paired with a white- morph individual and the other one may have been as well. A few other birds mottled with dusky on their back, wings, and (in some cases) tail I presumed to be immatures of the light morph. I saw no Red-footed Boobies away from the immediate vicinity of the colony other than one flying toward the colony from the ocean south of Wilkes Island on 31 March, suggesting that this species forages farther at sea. Great Frigatebird Fregata minor. I saw up to 225 birds roosting on powerlines across the man-made channel that nearly bisects Wilkes Island about midway along its length. Often, a few were seen there well into the morning and well before dusk as well. About 70% of the frigatebirds I observed at the atoll were immatures. Frigatebirds showed no indication of breeding during my visit. Only one of the sources that I have read (Fosberg 1966) specifically mentions frigatebirds’ nesting on the island, although most found a number of birds present (Sutterfield, for example, counted 274 on the powerlines). Fosberg (1966) found birds carrying twigs and “perhaps 10-12 pairs with eggs’ in trees on Wilkes Island just back of Kuku Point in March 1963. He also found a number of individuals roosting in trees and on the remains of an old pier, on both Peale and Wilkes islands, in April and July 1952, October 1953, and September 1961. Cattle Egret Bubulcus ibis. Hitchcock showed me photographs he had taken of a Cattle Egret, one of three that were present. The bird in the photographs was rather stocky and short-necked, with a relatively short yellow bill and black legs and feet, characters all typical of this species. It was photographed in the interior of the island in short grass. Although he did not record the date, his prints were processed on 16 October 1979. These birds could have been migrants or strays from eastern Asia or wanderers from the introduced Hawaiian population. Northern Pintail Anas acuta. Hitchcock has photographs of five females on a small freshwater pond near the air terminal. The photos were processed on 16 October 1979. According to him, ducks show up twice a year, apparently on a regular basis, but never more than seven birds at a time. Fosberg (1966) found one on a small pond on 8 March 1963 and mentioned that a resident had seen up to nine ducks at a time. This species was also mentioned by Casey (1966) as one of three duck species that occur rarely. 69 BIRDS OF WAKE ATOLL Black Kite Miluus migrans. I examined several photographs in Hitchcock's collec- tion of an individual that appeared around 1980 and stayed for about five years (Figures 3). The Black Kite is abundant in much of mainland Eurasia from the tropics nearly to the Arctic Circle, in Japan, and in much of Australasia, including Sulawesi, Papua New Guinea, and portions of the Solomon Islands. Populations in northern latitudes (M. m. lineatus in Asia) are long-distance migrants, but extralimital island records are rare. Amadon (1952) and Dickinson et al. (1991) reported a 1907 specimen of M. m. lineatus from Palawan. MacKinnon and Phillipps (1993) described this species as a “rare winter visitor” to Sumatra and Borneo. Interestingly, the specimen from Borneo is also M. m. lineatus (Smythies 1981) rather than the largely resident M. m. affinis from nearby Sulawesi. To the best of my knowledge, this species has been reported only three times before in the oceanic North Pacific. T. Lemke and T. Pratt observed an immature on Pagan Island in the northern Mariana Islands on 19 February 1984 (Glass et al. 1990), and one was seen on Tinian Island, also in the northern Marianas, from 25 July 1989 until 19 November 1990 (Stinson et al. 1991). Glass et al. also mentioned, without further details, an unpublished sighting from Midway Atoll “more than a decade ago. " Because of the paucity of extralimital records in the Pacific, the possibility that the Wake Atoll bird was ship-assisted must be considered. Black Kites are common in large ports such as Hong Kong, Shanghai, and Tokyo, where they may frequently be seen perched on ships’ riggings. Figure 3. Black Kite in flight, Wake Atoll, early 1980s. 70 Photo by Lou Hitchcock BIRDS OF WAKE ATOLL Pacific Golden-Plover Pluuialis fulua. This species is a common and widespread winter visitor on Wilkes and Wake islands, but is relatively scarce on Peale Island, which lacks open grassy habitats. I saw it primarily in short-cropped grassy areas, especially along the runway, taxiway, and golf course, but also on both outer and inner beaches. Johnston and McFarlane (1967) conducted a comprehensive study of the bioenergetics and seasonal status of the Pacific Golden-Plover on Wake Atoll. On the basis of seven visits between June 1963 and May 1965, they estimated that 200-500 winter on the atoll, with the first birds arriving in late July and the last departing in late May. Wandering Tattler Tringa incana. I saw several individuals daily in a variety of aquatic habitats, including outer rocky and pebbly beaches, calm channel shorelines, freshwater and brackish ponds, and sand flats in the inner lagoon. This species is a frequently recorded migrant (Fosberg 1966, Casey 1966, Johnston and McFarlane 1967). Siberian (Gray-tailed) Tattler Tringa breuipes. I saw and heard one individual in basic plumage at the freshwater pond between the tarmac and taxiway at the air terminal on 29 March. It gave a distinctive “tuwee tuwee” call, very unlike the “tlee- tlee-tlee-tlee” call of the Wandering Tattlers with which it was associating. This represents the first record of this species from Wake Atoll; however, it should be expected occasionally, as it is common in Micronesia and rare in the Hawaiian Islands (Pratt etal. 1987). Bristle-thighed Curlew Numenius tahitiensis. I examined photos of a probable Bristle-thighed Curlew taken by Hitchcock sometime in 1983 (photo processed in December 1983). Although the photographs are rather poor, the bird’s generally warm brown plumage suggests this species rather than the Whimbrel (Numenius phaeopus). Fosberg (1966) found a Bristle-thighed Curlew on 1 September 1961 and several from 7 to 9 March 1963. With no comment, Casey (1966) also listed this species for Wake. Ruddy Turnstone Arenaria interpres. I observed one feeding in the closely cropped grass at the west end of the runway on 25 March. However, during brief stops at Kwajalein Island (750 mi. south of Wake) while traveling to and from Wake, I found this species abundant. Fosberg (1966), Johnston and McFarlane (1967), and Wetmore (Rice and Kenyon 1962) found small numbers in July, August, October, and March, suggesting that it is an expected migrant on Wake. Gray-backed Tern Sterna Iunata. This species is confined to the tropical Pacific from Hawaii south to the Tuamotu Archipelago, Tonga, and Fiji, and west to the Marianas (Harrison 1985). I saw eight, four, and seven individuals, respectively, on 26 and 27 March and 1 April, perched on and flying around a cluster of wooden posts just offshore on the lagoon side of the causeway between Wake and Wilkes islands. I saw no indication of breeding. Harrison (1990) listed Wake as one of the islands where the Gray-backed Tern breeds but gave no specific information. Casey (1966) listed it as present but did not elaborate. Sooty Tern Sterna fuscata. This is far and away the most abundant bird on Wake Atoll (Figure 4). There was a large breeding colony at the west end of Wilkes Island and a smaller colony on Peale Island at the time of my visit. I also found evidence of two recently active colonies elsewhere on Peale; however, no birds breed on Wake Island proper. The Wilkes colony occupied 18,000 m 2 at the west end of an expansive grassy area just above the shoreline. The number of adults in this colony at the time of my visit varied between approximately 10,000 and 25,000, the higher figures being counted at dawn and dusk. The number of young 1 estimated at approximately 3000-3500, by extrapolation from counts of various sections of the 71 BIRDS OF WAKE ATOLL colony. There were an estimated 9800 eggs in the colony, but none examined were viable and most were cracked or broken. Young birds varied from only a few days old to nearly full grown. No flying young were seen in this colony the first two days, but one was seen on 26 and 27 March flying over the shoreline just west of the colony. I observed no predation on Sooty Tern eggs or young; however, a feral cat ventured into the colony on 27 March. The cat did not attempt to capture any young but rather seemed intent on exiting the colony as quickly as possible. On Peale Island the only breeding Sooty Terns were on and immediately adjacent to Flipper Point. Young birds were in groups along the shoreline, and a few were in the vegetation just above the shoreline. An estimated 300 young were in this colony; however, a direct count was not possible because of dense vegetation. In contrast with the Wilkes colony, many young in this colony had fledged and were flying about the colony on 24 March and afterward. The average unfledged bird was also about IV 2 to 2 weeks more advanced here than on Wilkes. Island residents mentioned that there were considerably more birds (adults) on Peale a few weeks prior to my visit (one used the term “millions”). I found evidence of recent nesting near Ripper Point and at the west end of Peale, where I observed dead chicks and non-viable eggs. There were approximately 500 eggs and an undetermined number of dead chicks of all ages, as well as about ten dead adults. The age of the carcasses prevented any determination of cause of death. At the extreme west end of Peale I found fewer than 20 carcasses of hatchlings in a small clearing at the end of the road. I found no evidence of nesting anywhere else on Peale. Much of Peale Island is heavily vegetated with shrubs of Tourrtefortia argentea , Scaevola sericea, and Pemphis acidula so is not suitable for Sooty Terns. Bailey (1951) described the Sooty Tern colony on Peale Island as “the largest I had ever seen,” suggesting that it was much larger than the one I observed, although he Figure 4. Incubating Sooty Tern, Wake Atoll. 72 Photo by Lou Hitchcock BIRDS OF WAKE ATOLL did not estimate its size, saying only that he saw “thousands of birds on their eggs” on 15 May. The Pacific Ocean Biological Survey Program (unpubl. field notes; Gould 1974) reported 1,750,000 Sooty Terns on Wake Island from 1964 to 1966. Fosberg (1966) found a “considerable rookery” on Peale on 20 and 21 April 1952 with “young in various stages of pin feathering to almost full grown. In October 1953 he found a “small flock near the western tip of Peale Island, including “almost fully grown young.” On 8 and 9 March 1963, he found thousands of birds present, “with fully grown young, able to fly when approached.” Casey (1966) reported “250,000 to 1,000,000 birds” in 1966. Rowland (1990) visited the island in early April 1989 and found approximately 250.000 nestling Sooty Terns in a 48,000-m 2 colony at the west end of Wilkes Island. This stands in stark contrast to the 3000 to 3500 chicks I found in a colony only three-eighths this size at virtually the same time of year when the birds were in about the same stage of their breeding cycle. Rowland also found considerably more birds on Peale Island. He estimated about 100,000 chicks on Flipper Point alone and 43.000 more in the general vicinity. Sutterfield (1990) found no evidence of nesting on Wilkes Island in late October 1989, but did find ‘“a few eggs” on the northwest point of Peale Island. He did not indicate if they were being incubated. Hitchcock told me that Sooty Terns were formerly much more common and the feral cats have substantially reduced their numbers. He said that others had told him that a single cat working at night can kill up to 100 chicks and so disrupt the colony that many additional young become isolated from their parents in the dense vegeta- tion and die. He said the tern colony once took up the entire graded area (the west end of Wilkes is graded every year to attract the terns away from areas around the runway where they would nest otherwise) but now takes up only about one-sixth of that area. Most Sooty Terns at Wake nest in the spring, as on Hawaii; however, the timing of breeding on Wake and elsewhere in the central and eastern Pacific is poorly understood, with different colonies on the same island sometimes nesting at different times of the year (Ashmole 1963, Gould 1974). At least in 1989 and 1993, incubation had ended by late March and early April, suggesting a somewhat earlier breeding season in these years, although Bailey (1951) found Sooty Terns still on eggs in May. Brown Noddy Anous stolidus. I found eight birds and two freshly constructed nests on top of a concrete bunker at the outer perimeter of the Sooty Tern colony on Wilkes on 26 March. The same day I saw four birds perched, one with vegetation in its beak, atop a rather large offshore coral “rock” covered with whitewash off the west end of Wilkes. On 28 March, one nest with an egg was located atop a large concrete block in the lagoon near the golf course on Wake Island proper. Also on this date, a flock of 65 noddies circled for much of the day around a cluster of Casuarina trees on the golf course and perched on offshore coral near the golf course. By 29 March the flock had grown to 90. Scattered other individuals were seen throughout the atoll flying along the shore or feeding offshore, with total numbers on the atoll increasing noticeably during my visit, Fosberg (1966) found one nest (contents not given) and several birds on 20 and 21 April 1952, and a nest with a half-grown young on 22 and 23 October 1953. Casey (1966) mentioned Brown Noddies as abundant, “although [their nests] are sometimes hard to locate.” Black Noddy Anous minutus. I saw two individuals perched with Brown Noddies on a concrete structure just offshore along the outer beach opposite the golf course on 29 March. This species is rare at Wake, and its breeding has not been suspected by past observers. 73 BIRDS OF WAKE ATOLL White Tern Gygis alba. I saw three birds in flight near the west end of the runway on 24 March. I then saw none until 28 March, when I observed six circling around and perched in the cluster of Casuarina trees at the golf course on the main island. I saw these birds there every day subsequently until my departure on 1 April but saw no courtship behavior. Fosberg (1966) found several birds in April 1952, October 1953, September 1961, and March 1963, but no indication of breeding. Rock Dove (Feral Pigeon) Columba livia. 1 observed a flock of eleven birds on 28 March and six birds on 29 March in the vicinity of the golf course. They are apparently being bred by an island resident (Rowland 1990). Short-eared Owl Asio flammeus. 1 flushed one from beneath a small Pemphis bush at the southwest corner of the catchment basins late in the morning of 28 March, and a few minutes later observed the bird flying low over the open scrubby area between the catchment basins and the golf course. Although this species is unrecorded in the literature from Wake Atoll, Hitchcock has seen owls (presumably Short-eared) at Wake on several occasions. He usually sees them in vehicle headlights when flushed from the roadside at night. Other species reported in the literature fiom Wake Atoll but not recorded by Hitchcock or me are the Christmas Shearwater, Puffinus natiuitatis (Pratt et al. 1987:344), Garganey, Anas querquedula (Casey 1966, Johnston and McFarlane 1967), Northern Shoveler, A. clypeata (Casey 1966, Johnston and McFarlane 1967), “yellowlegs” (Casey 1966), Sander- ling, Calidris alba (Casey 1966, Johnston and McFarlane 1967), Sharp- tailed Sandpiper, C. acuminata (Casey 1966, Johnston and McFarlane 1967), Dunlin, C. alpina (Casey 1966, Johnston and McFarlane 1967), and Common Snipe, Gallinago gallinago (Johnston and McFarlane 1967). ACKNOWLEDGMENTS 1 am grateful to Lou Hitchcock for graciously lending me his prints for publication, and to the U. S. Army Space and Strategic Defense Command, the Earth Technol- ogy Corporation, and MBA International for the opportunity to visit the island. Doug Pratt and Roger Clapp provided many useful comments on an earlier draft of this manuscript. LITERATURE CITED Amadon, D. 1952. A bird new to Palawan. Phil. J. Sci. 81:139. Ashmole, N. P. 1963. The regulation of numbers of tropical oceanic birds. Ibis 103:458-473. Bailey, A. M. 1951. Notes on the birds of Midway and Wake islands. Wilson Bull. 63:35-37. Bryan, Jr., E. H. 1959. Notes on the geography and natural history of Wake Island. Atoll Res. Bull. 66. Casey, E. 1966. The birds of Wake Island. ’Elepaio 26(7):69-70. Dickinson, E. C., Kennedy, R. S, and Parkes, K. C. 1991. The birds of the Philippines. Br. Ornithol. Union Check-list 12. Fosberg, F. R. 1966. Northern Marshall Islands land biota: Birds. Atoll Res. Bull. 114. 74 BIRDS OF WAKE ATOLL Glass, P. O., Reichel, J. D., Lemke, T. O., Clapp, R. B., Wiles, G. J., Aldan, D. T., and Pratt, T. K. 1990. New migrant and vagrant bird records for the Mariana Islands, 1978-1988. Micronesica 23:67-89. Gould, P. J. 1974. Sooty Tern (Sterna fuseata), in Pelagic studies of seabirds in the central and eastern Pacific Ocean (W. B. King, ed.), pp. 6-52. Smithsonian Contr. Zool. 158. Gould, P. J., King, W. B., and Sanger, J. A. 1974. Red-tailed Tropicbird (Phaethon rubricauda), in Pelagic studies of seabirds in the central and eastern Pacific Ocean (W. B. King, ed.), pp. 206-231. Smithsonian Contr. Zool. 158. Harrison, C. S. 1990. Seabirds of Hawaii: Natural History and Conservation. Comstock Publ. Assoc., Cornell Univ. Press, Ithaca, N. Y. Harrison, P. 1985. Seabirds: An Identification Guide (rev. ed.). Houghton Mifflin, Boston. Johnston, D. W., and McFarlane, R. W. 1967. Migration and bioenergetics of flight in the Pacific Golden Plover. Condor 69: 156-168. MacKinnon, J., and Phillipps, K, 1993. A Field Guide to the Birds of Borneo, Sumatra, Java, and Bali. Oxford Univ. Press, Oxford, England. Pratt, H. D., Bruner P. L., and Berrett, D. G. 1987. A Field Guide to the Birds of Hawaii and the Tropical Pacific. Princeton Univ. Press, Princeton, N. J. Rice, D. W., and Kenyon, K. W. 1962. Breeding distribution, history, and popula- tions of north Pacific albatrosses. Auk 79:365-386. Rowland, C. M. 1990, Biological survey. Wake Island Starlab sites. Trip report — Wake Atoll (April 4-11, 1989). Environmental Impact Analysis Process Final Environmental Assessment, Starlab Program, U. S. Fish and Wildlife Service, Appendix A. Pacific Islands Office, P. O. Box 50167, Honolulu, HI 96850. Sanger, G. A. 1974. Laysan Albatross ( Diomedea immutabilis ), in Pelagic studies of seabirds in the central and eastern Pacific Ocean (W. B, King, ed.), pp. 129- 153. Smithsonian Contr. Zool. 158. Smythies, B. E. 1981. The Birds of Borneo (3rd ed.). Sabah Society, Kota Kinabalu, and Malayan Nature Society, Kuala Lumpur, Malaysia. Stinson, D. W., Reichel, J. D., Craig, R. J., and Aldan, D.T. 1991. New and unusual bird records from the northern Mariana Islands, 1988-1990. Micronesica 24:261-271. Sutterfield, T. 1990. Seabird survey of Project Starbird construction sites on Wake Atoll. Environmental Impact Analysis Process Final Environmental Assessment, Starlab Program, Appendix D. U. S. Fish and Wildlife Service, Pacific Islands Office, P. O. Box 50167, Honolulu, HI 96850. Vaughn, C. 1945. Observations on the birds of Wake Island. Migrant l6(2):26-28. Accepted 21 February 1995 75 SEX RATIOS AND BILL GROWTH IN NESTLING BLACK-CHINNED HUMMINGBIRDS ELIZABETH P. ELLISTON, Wildlife Rescue Inc. of New Mexico, 1619 Saunders SW, Albuquerque, New Mexico 87105 WILLIAM H. BALTOSSER, Department of Biology, University of Arkansas at Little Rock, Little Rock, Arkansas 72204 Implicit in the analysis of sex ratios in wild bird populations is the assumption that equal numbers of males and females are conceived, hatched, and fledged. Sex ratios biased in favor of females have been reported for the Broad-tailed Hummingbird ( Selasphorus platycercus ) by Calder et ah (1983) and Calder (1990) and the Ruby-throated Humming- bird ( Archilochus colubris) by Mulvihill et al. (1992) and Bill Hilton (in litt). Our data for the Black-chinned Hummingbird ( Archilochus alexandri) are, to our knowledge, the first attempt at providing empirical support for sex ratios in hummingbirds being equal at conception, hatching, and fledging. Validating this assumption is an important first step in examining the phenomenon of biased sex ratios in adults. In addition, our data show that bill length can be useful in determining the age of nestlings. METHODS Most Black-chinned Hummingbird nestlings we studied were received by Elliston through Wildlife Rescue Inc. of New Mexico after their mothers had abandoned them. Others were examined after the limb to which their nest was attached had been sawed down. In these cases, after the adult female was located, the nests were wired back into the tree and the female continued to care for her young. Elliston successfully reared most orphaned birds, though occasionally birds were dead upon arrival or did not survive. These were autopsied, sexed, and preserved as voucher specimens. Less than 10% of our data are from birds that Baltosser obtained in the field during other hummingbird investigations, some dating back to 1976 (e.g., Baltosser 1986, 1989). Hummingbirds invariably lay two eggs (Skutch 1973, Johnsgard 1983). Since sibling pairs constitute a brood, data on them are separated from other data (i.e. , birds of uncertain relationship received by Wildlife Rescue) to make this subset clearly visible. For the purpose of assessing sex ratios, however, all available information has been used. The 15 birds of unknown sex (8.5% of the total) were ultimately allocated equally between males and females, but only after we determined that apportioning them otherwise did not alter the statistical significance ( P 0.05). Birds in the non paired data set have been assigned to one of three age categories on the basis of bill length and growth curves: pre-fledgling nestlings (bill 13.0 mm), fledglings (bill >13.0 mm 17.0 mm), and post- fledgling juveniles (bill >17.0 mm). This system supplements Ortiz-Crespo (1972) and Baltosser (1987) by extending the use of the bill in aging to birds in even earlier stages of development. 76 Western Birds 26:76-81, 1995 NESTLING BLACK-CHINNED HUMMINGBIRDS Bill-growth rates were determined from orphaned and displaced Black- chinned Hummingbirds brought to Wildlife Rescue of New Mexico over eight years. Elliston took daily bill measurements from the bird’s receipt to its release. As the day of hatching of most birds was unknown, an age of 21 days was assigned to each on the day of first flight (Bene 1945, Bent 1940, Cogswell 1949, Skutch 1973, Tyrrell 1985). The age at each previous measurement was then established after the date of fledging became evident. At the beginning of the study, we used vernier calipers accurate to the nearest 0.1 mm. Since 1991 we have adopted digital calipers accurate to 0.02 mm. Characteristics of wing and tail feathers were the primary means of sex determination (Baldridge 1983, Baltosser 1987). Birds having a notch at the tip of the sixth primary, a pointed and angular fifth rectrix, and a reduced amount of white at the tip of the third rectrix were classified as male. Nestlings lacking these feather specializations and having large amounts of white at the tip of the third rectrix were classified as female. The data set representing complete two-chick broods may be minimal from a statistical standpoint (N = 36 nests, 72 individuals — including 2 individuals of unknown sex). When combined with the non-paired data (105 individuals — including 13 individuals of unknown sex), however, the data are sufficiently robust to sustain the validity of our conclusion. Data sets were statistically analyzed with G tests of independence in conjunction with Williams’ correction (Sokal and Rohlf 1981). The former statistically com- pares our observed ratio of males to females to the theoretically expected ratio of one male to every female. RESULTS AND DISCUSSION Bill Growth Figure 1 shows the growth of the bill in young birds from a length of less than 4 mm at hatching to over 13 mm at the end of 21 days, the usual age at fledging (average increment = 0.51 mm/day). The variability between day 1 and day 17 may have been influenced by several conditions. Few very young birds came to Wildlife Rescue, and those that did were growing on an artificial diet, perhaps not as conducive to optimal growth as a natural diet. Since growth of very young birds is rapid, even slight variability in the intervals of measurement can result in proportionately large changes in bill length. Additionally, because of poor feather condition, birds orphaned very young and raised on an artificial diet sometimes were unable to fledge, making estimates of their age, back-dated from time of first flight, unreli- able. The bill lengths of birds acquired from the wild at over two weeks of age varied less. The bills of fledglings continue to grow at a rate just slightly less (0.44 mm/day) than the nestlings’ rate for about 2 weeks after fledging (Figure 1). The growth rate of juveniles diminishes (0.04 mm/day) over the next 14 days (weeks 6 and 7) as bills attain their full length. Male and female Black- chinned Hummingbirds are sexually dimorphic (Stiles 1971, Baltosser 77 NESTLING BLACK-CHINNED HUMMINGBIRDS 1987), and this dimorphism becomes evident in bill length at about the time of fledging (Figure 2). We devised predictive equations based on bill length to estimate a young Black-chinned Hummingbird’s age. The 21-day data set yielded the follow- ing, where x represents bill length and y represents age: y = 1.96x - 3.94. That is, every 1 mm increase in bill length takes 1.96 days, a daily increase of ca. 0.51 mm/day. The 35-day data set yielded y = 2.02x - 4.43. The r-square values for these equations are 0.98 and 0.99, respectively. In other words, 98 to 99% of the variation in age can be explained (predicted) on the basis of the variation in bill length. Sex Ratios Even though most nestlings brought to Wildlife Rescue were reared under artificial conditions, this should not bias our conclusions concerning sex ratios at conception or hatching. We also believe that sex ratios of fledglings are similar to those of birds reared in the wild. Our logic stems from research conducted by Baltosser (1986), which revealed that between 32 and 47% of all Black-chinned nests that fail because of predation are lost early, to predation on eggs rather than on chicks. An additional 2 to 6% of nests containing eggs are lost to other causes. Mortality ascribed to preda- tion of nestlings ranges from 10 to 19%, with an additional 2 to 10% lost to E E 0Q 20 18 16 14 12 O) io C 0.05). If we assume that the 36 nests (sex of young in 1 nest not known) were a random, representative sample of the entire population, then the 72 nestlings should be equally divided between males and females. The G-test statistic for the 37 males and 35 females (unknown apportioned equally) is 0.06 (P > 0.05). Thus, there is no reason to reject our hypothesized 1:1 ratio. Nonsiblings . — Data for single birds and pairs for which there was no guarantee of relatedness are shown in Table 1 . The sex ratio in this sample varied greatly from year to year. Collectively, however, the data support the hypothesis of equal sex ratios for nestlings (G = 0.42, P > 0,05) and fledglings (G = 0.37, P > 0.05). This is not true for post-fledgling juveniles (G = 6.15, P < 0.05), however, as more males than females are brought to Wildlife Rescue for care. E E 20 18 16 14 12 •• • O) io C 5 8 5 6 4 2 □ Females ( n = 16 ) # Males ( n = 25 ) „ □ * □ •* , D • • • □ B B* □ « • • □ a • □ * • • /•S D ' □ Qcr • ’ □ Immature Black-chinned Hummingbirds 10 15 20 25 30 35 40 45 50 Age ( days ) Figure 2. Bill length vs. age in young Black-chinned Hummingbirds. Squares, females (n = 16); circles, males (n = 25). 79 NESTLING BLACK-CHINNED HUMMINGBIRDS Table 1 Numbers of Nonsibling Black-chinned Hummingbirds by Sex and Age Age. (days) Males Females Sex undetermined Nestlings (1-20) 15 19 4 Fledglings (21—35) 20 16 7 Juveniles (36—49) 17 5 2 CONCLUSIONS Our observations suggest that bill length, even in very young birds, can be a useful indicator of developmental age from hatching to independence. Similar growth patterns should be investigated in other hummingbird spe- cies. In the Black-chinned Hummingbird, the sex ratio of nestlings remains at 1:1 through fledging. Under Mendelian segregation, because birds have discrete sex chromosomes, a 1:1 ratio between males and females is to be expected (see Charnov 1982). Our data, however, suggest the ratio may shift shortly after fledging in favor of females. To our knowledge, this is the first attempt at providing empirical support for sex ratios in hummingbirds being equal at conception, hatching, and fledging. We hope our work with the Black-chinned Hummingbird will stimulate others to investigate growth and sex ratios in other hummingbird species that can be sexed at an early age. Prime candidates in the western U.S. include the Anna’s ( Calypte anna; see Williamson 1956, Stiles 1971, Baltosser 1987), Costa’s ( Calypte costae; see Stiles 1971, Baltosser 1987), and Calliope ( Stellula calliope; see Stiles 1971, Baltosser 1994). In the eastern U.S. work should continue (see Southwick and Gates 1975) on the Ruby-throated Hummingbird (see Leber man 1972, Baltosser 1987). Such efforts will ultimately provide a basis from which the phenomenon of femaie-biased sex ratios in adult birds can be better assessed. ACKNOWLEDGMENTS We thank the Bird Banding Lab, the Albuquerque office of the U.S. Fish and Wildlife Service, the Arizona Game and Fish Department, and the New Mexico Department of Game and Fish for permits. Financial assistance was provided by the Share With Wildlife Program of the New Mexico Department of Game and Fish. We thank the many individuals who brought hummingbird nestlings to the attention of Wildlife Rescue of New Mexico Inc. Constructive criticism of an earlier draft of this manuscript was provided by J. P. Hubbard, D. W. Inouye, and W. A. Calder. We also thank Philip Unitt for his insight and many helpful suggestions. LITERATURE CITED Baldridge, F. A. 1983. Plumage characteristics of juvenile Black-chinned Humming- birds. Condor 85:102-105. Baltosser, W. H. 1986. Nesting success and productivity of hummingbirds in south- western New Mexico and southeastern Arizona. Wilson Bull. 98:353-367. 80 NESTLING BLACK-CHINNED HUMMINGBIRDS Baltosser, W. H. 1987. Age, species, and sex determination of four North American hummingbirds. N. Am. Bird Bander 12:151-166. Baltosser, W. H. 1989. Nectar availability and habitat selection by hummingbirds in Guadalupe Canyon. Wilson Bull. 101:559-578. Baltosser, W. H. 1994. Age and sex determination in the Calliope Hummingbird. W. Birds 25:104-109. Bene, F. 1945. The role of learning in the feeding behavior of Black-chinned Hummingbirds. Condor 47:3-21. Bent, A. C. 1940. Life histories of North American cuckoos, goatsuckers, humming- birds, and their allies. U.S. Natl. Mus. Bull. 176. Calder, W. A. 1990. Avian longevity and aging, in Genetic Effects on Aging II (D. E. Harrison, ed.), pp. 185-204. Telford Press, Caldwell, N.J. Calder, W. A., Waser, N. M., Hiebert, S. M., Inouye, D. W., and Miller, S. 1983. Site- fidelity, longevity, and population dynamics of Broad-tailed Hummingbirds: A ten-year study. Oecologia 56:689-700. Charnov, E. L. 1982. The Theory of Sex Allocation. Princeton Univ. Press, Princeton, N.J. Cogswell, H. L. 1949. Alternate care of two nests in the Black-chinned Humming- bird. Condor 51:176-178. Johnsgard, P. A. 1983. The Hummingbirds of North America. Smithsonian Inst. Press, Washington, D C. Leberman, R. C. 1972. Identify, sex, and age it. Key to age and sex determination of Ruby-throated Hummingbirds in autumn. Inland Bird Banding News 44:197- 202 . Mulvihill, R. S., Leberman, R. C., and Wood, D. S. 1992. A possible relationship between reversed sexual size dimorphism and reduced male survivorship in the Ruby-throated Hummingbird. Condor 94:480-489. Ortiz-Crespo, F. I. 1972. A new method to separate immature and adult humming- birds. Auk 89:851-857, Skutch, A. F. 1973. The Life of the Hummingbird. Crown, New York. Sokal, R. R., and Rohlf, F. J. 1981. Biometry. W. H. Freeman, New York. Southwick, E. E., and Gates, D. M. 1975. Energetics of occupied hummingbirds nests, in Perspectives of Biophysical Ecology (D. M. Gates and R. B. Schmerl, eds.), pp. 417-430. Springer- Verlag, New York. Stiles, F. G. 1971. On the field identification of California hummingbirds. Calif. Birds 2:41-54. Tyrrell, E. Q., and Tyrrell, R. A. 1985. Hummingbirds, Their Life and Behavior. Crown, New York. Williamson, F. S. L. 1956. The molt and testis cycle of the male Anna Hummingbird. Condor 58:342-366. Accepted 23 January 1995 81 DISTRIBUTION AND ABUNDANCE OF SNOWY PLOVERS WINTERING IN THE INTERIOR OF CALIFORNIA AND ADJACENT STATES W. DAVID SHUFORD, GARY W. PAGE, and CATHERINE M. HICKEY, Point Reyes Bird Observatory, 4990 Shoreline Highway, Stinson Beach, California 94970 Since the late 1970s, broad-scale surveys for the Snowy Plover ( Charadrius alexandrinus ) have been conducted in many western states (Page and Stenzel 1981, Wilson-Jacobs and Meslow 1984, Page et al. 1986, Herman et al, 1988, Halpin and Paul 1989, Page et al, 1991). In California, surveys of the breeding population have covered the entire state (Page and Stenzel 1981, Page et al. 1991), whereas surveys of the wintering population have focused mostly on the coast (Page et al. 1986). Knowledge of the status of the species in the interior in winter is therefore fragmentary (Page et al. 1986). Here we report the migration schedule, distribution, abundance, and habitat use of Snowy Plovers wintering in the interior of California based on the first comprehensive surveys of key wintering areas in the San Joaquin Valley and the Mojave and Colorado deserts. We also summarize records of plovers from other sites where they infrequently winter in the interior of California and other western states. METHODS As part of Point Reyes Bird Observatory’s (PRBO) Pacific Flyway Project, we organized winter surveys of all shorebirds using most open shallow- water habitats in California’s Central Valley, Mojave and Colorado deserts, and southern Great Basin desert. On the basis of prior knowledge (H, Coe, R. Marsh in litt.) and our initial surveys, we determined that 19 sets of agricultural evaporation ponds (totaling about 2576 hectares) were the primary wintering area for Snowy Plovers in the southern San Joaquin Valley (Figure 1). We surveyed these ponds at least once during each of the periods 6 November-1 December 1991, 15-31 January 1992, 18-30 November 1992, 23 January-5 February 1993, 9-29 November 1993, 15 January-1 February 1994, 9-22 November 1994, and 28 January-22 February 1995. Observers drove or walked impoundment dikes and care- fully scanned suitable plover habitat with binoculars and spotting scopes. Roster et al. (1992) described the physical and biological characteristics of these highly productive saline impoundments. Our standard multi-species shorebird surveys of the Salton Sea, Riverside and Imperial counties (21-22 November 1992, 6 February 1993, 21-22 January 1994), proved inadequate to detect many of these cryptic plovers on the broad beaches of the sea’s vast shoreline. Hence, from 3 to 8 December 1993 and 1 to 9 December 1994 we made thorough specific searches for plovers in all areas of the Salton Sea with suitable habitat. Once to twice per winter from November 1991 to February 1995 we also surveyed most other areas possibly important to Snowy Plovers in the San Joaquin Valley and the southern Great Basin, Mojave, and Colorado deserts Western Birds 26:82-98, 1995 82 WINTERING SNOWY PLOVERS adapted from Moore et al. (1990) Figure 1. Agricultural evaporation ponds in the Tulare Basin of the San Joaquin Valley, California. 1. Britz Five Points; 2, Stone Land Co.; 3, Westlake Farms North; 4. Fabry Farms; 5, Meyers Ranch; 6. Barbizon Farms; 7. Tulare Lake Drainage District (TLDD) North; 8, Westlake Farms South; 9. Pryse Farms; 10. Bowman Farms; 11, Morris Farms; 12, Martin Farms; 13, 4-J Corp.; 14, TLDD Hacienda; 15, TLDD South; 16, Lost Hills Water District; 17, Carmel Ranch; 18, Lost Hills Ranch; 19, Rainbow Ranch. 83 WINTERING SNOWY PLOVERS of California (Appendix 1). Although we tried to make exhaustive surveys for plovers at all sites, we probably detected a higher percentage of plovers at the smaller, more contained sites, such as diked evaporation ponds, than at larger sites with long broad beaches or expansive alkali flats, such as the Salton Sea or Owens Lake. Lacking a color-banded population, we were unable to estimate detection rates for wintering plovers as Page et al. (1986, 1991) did for breeding plovers. For additional winter records of Snowy Plovers from the interior of the western U.S., we searched the published literature, including the seasonal reports and Christmas Bird Counts (CBCs) in Audubon Field Notes (AFN), American Birds (AB), and National Audubon Society Field Notes (NASFN), and contacted regional and local experts in California, Washing- ton, Oregon, Nevada, Arizona, and New Mexico. These sources helped us to characterize the seasonal limits of the Snowy Plover’s period of winter residency. RESULTS Period of Winter Residency For the interior of the West, the period of winter residency for Snowy Plovers is primarily November through February (Page et al. 1986). Fall departure from breeding sites varies regionally. In southern New Mexico, most fall migrants leave by early to mid-October but some linger into early November [e.g., up to 20 at Bitter Lake National Wildlife Refuge (NWR), Chaves County, on 2 November 1973; AB 28:88]. Along the lower Colorado River, Snowy Plovers are rare and irregular after September (Rosenberg et al. 1991) but may remain in fall until mid-November (Phillips et al. 1964). In the southern California deserts away from regular wintering sites, Snowy Plovers typically stay only until mid- to late September (T. and J. Heindel, J. Tarble in litt.). In Nevada, Snowy Plovers occasionally linger in fall into November (Alcorn 1988). At colder sites in the wintering range, such as Harper Dry Lake and the Lancaster sewage ponds in the Mojave Desert of California, numbers of Snowy Plovers appear to dwindle over the winter (K. Garrett, E. Cardiff pers. comm.). By contrast, in areas of milder winters, such as the Salton Sea and San Joaquin Valley, plover numbers appear to remain fairly constant throughout the winter (see below). The timing of the first influx of spring migrants to interior breeding areas generally ranges from early to late March. In southern New Mexico, early arrivals in spring have ranged from 8 to 17 March (AB 25:609, 26:639, 28:607, 39:336, 46:460), and large numbers have been detected as early as 22 March (1974, 124 at Bitter Lake NWR; AB 28:674). Late February records for New Mexico (see below) are problematic and may represent either wintering birds or very early spring migrants. Along the lower Colorado River, Snowy Plovers may arrive in spring by late March (Phillips et al. 1964, Rosenberg at al. 1991). They have arrived in the southern California deserts as early as 13 March (1974, Tecopa, Inyo County; J. Tarble in litt.) and build up rapidly thereafter (e.g., 24 at Edwards Air Force 84 WINTERING SNOWY PLOVERS Base, Kern County, on 24 March 1990; AB 44:496). In Nevada, Snowy Plovers arrive as early as 22 March (Alcorn 1988). Wintering Status In the interior of the West most wintering Snowy Plovers were found at evaporation ponds in the San Joaquin Valley and at the Salton Sea. The remaining plovers were found primarily at alkali lakes in the southern deserts. San Joaquin Valley. The vast majority of the wintering Snowy Plovers on our surveys of the San Joaquin Valley were in evaporation ponds created to dispose of the salt-laden subsurface drain waters from irrigated fields (Table 1, Figure 1). Snowy Plovers were found on 10 of 19 evaporation- pond systems surveyed. Over four winters, totals for these ponds ranged from 79 to 185 (mean 135.2, standard error (SE) 18.8] plovers in Novem- ber and from 53 to 174 (mean 101.0, SE 23.8) in January. The Westlake Farms North and Tulare Lake Drainage District’s (TLDD) Hacienda Ranch ponds usually held the most plovers, except in November 1993 and 1994, when TLDD South held 95 and 68 birds, respectively (Table 1). Plover numbers at individual pond systems varied over the course of a winter, as demonstrated by nine counts from 15 November 1993 to 25 February 1994 at the Westlake North and Westlake South ponds, where totals ranged from 21 to 61 (mean 39.3, SE 3.5) and 3 to 31 (mean 12.3, SE 3.4), respectively (J. Seay in litt.). Other Snowy Plovers encountered on our surveys of the San Joaquin Valley were found on managed duck clubs in the Table 1 Number of Snowy Plovers Counted at Agricultural Evaporation Ponds in the Southern San Joaquin Valley, California, in the Winters from 1991-92 to 1994-95 Pond System Name 0 1991- -92 1992-93 1993-94 1994-95 Nov Jan Nov Jan Nov Jan Nov Feb Jack Stone Land Co. 0 17 0 0 0 0 8 0 Westlake Farms North 77 5 48 47 48 35 19 0 Westlake Farms South 2 1 9 36 3 3 12 15 Bowman Farms 0 9 D b D D D D D Morris Farms 0 1 0 1 0 D D D Martin Farms 0 0 0 2 0 0 D D TLDD Hacienda 0 13 79 80 35 62 25 34 TLDD South 0 5 4 2 95 11 68 10 Lost Hills Ranch 0 2 D 0 D D D D Rainbow Ranch 0 0 0 6 4 1 5 6 Totals 79 53 140 174 185 112 137 65 °No plovers were detected at 9 other sets of evaporation basins also surveyed during the same time periods in 1991-92 to 1994-95 (see Methods and Figure 1). b D, evaporation basin dry at time of survey. 85 WINTERING SNOWY PLOVERS Grasslands wetlands complex near Los Banos, Merced County, at alkali ponds, or at sewage ponds (Appendix 1). Page et al. (1986) listed the few records of Snowy Plovers wintering in the San Joaquin Valley before 1985. Subsequent winter records for the San Joaquin Valley, beyond ours for the Tulare Basin, are cited in Appendix 2. Salton Sea. On multi-species shorebird surveys of varying amounts of the Salton Sea shoreline, not specially aimed at Snowy Plovers, observers tallied 112 plovers on 23 November 1991, 48 on 21 and 22 November 1992, 66 on 3 February 1993, and 40 on 21 and 22 January 1994. Our complete surveys of the Salton Sea, 3-8 December 1993 and 1-9 Decem- ber 1994, which emphasized a thorough count of Snowy Plovers, yielded totals of 285 and 214, respectively (Table 2). The December totals were similar to or surpassed the breeding-season totals of 226 in May 1978 and 198 in May 1988 (Table 2). The distribution of wintering Snowy Plovers in 1993 and 1994 was generally similar to that of breeding birds, with the majority found along the western and southeastern shorelines (Table 2, Table 2 Number of Snowy Plovers Counted in Winter along Various Segments of the Salton Sea, California (see Figure 2), with Comparisons to Prior Breeding Seasons 4-12 4-14 3-8 1-9 May May Dec Dec Shoreline Segment 1978 a 1988 b 1993 1994 (1) Whitewater R. delta (2) Whitewater R.-Desert Shores (3) Desert Shores-Salton Sea Beach (4) Salton Sea Beach-Lido Palms (5) Lido Palms-Iberia Wash (6) Iberia Wash-Naval Test Base (7) Naval Test Base (8) San Felipe Creek delta (9) San Felipe Creek-Barth Rd. (10) Poe Road (11) Near New River jetty (12) Salton Sea NWR (13) McDonald Rd.-Wister Unit (14) Imperial Wildlife Area (Wister Unit) ponds (15) North Wister-Niland Marina (16) Niland Marina-Bombay Beach (17) Bombay Beach (18) near Bob's Playa Riviera (19) Salt Creek Beach (20) Desert Beach Totals 2 4 14 3 0 0 10 0 12 8 0 1 7 14 46 16 32 18 21 9 38 14 102 31 0 24 17 16 29 38 26 18 3 3 0 7 0 0 15 3 2 0 0 0 0 7 3 0 16 17 10 89 5 13 3 9 33 11 0 0 29 26 13 7 4 1 0 1 6 0 0 0 6 0 0 0 2 0 5 4 226 198 285 214 °Data from Henderson and Page (1979). b PRBO unpublished data summarized by Page et al. (1991). 86 WINTERING SNOWY PLOVERS Figure 2); wintering birds were, however, more clumped at roosting sites or favored feeding areas than were breeding birds. In 1993 two areas of concentration stood out: 46 birds were roosting at one site between Salton 0 10 20 Figure 2. Salton Sea, California. Numbered sites or segments of the shoreline: 1, Whitewater R. delta; 2, Whitewater R -Desert Shores; 3, Desert Shores-Salton Sea Beach; 4, Salton Sea Beach-Lido Palms; 5, Lido Palms-Iberia Wash; 6, Iberia Wash-Naval Test Base; 7, Naval Test Base; 8, San Felipe Creek delta; 9, San Felipe Creek-Barth Rd.; 10, Poe Road; 11, near New River jetty; 12, Salton Sea NWR; 13. McDonald Rd,-Wister Unit; 14, Imperial Wildlife Area (Wister Unit) ponds; 15, north Wister-Niland Marina; 16, Niland Marina-Bombay Beach; 17, Bombay Beach; 18. near Bob’s Playa Riviera; 19, Salt Creek Beach; 20, Desert Beach. 87 WINTERING SNOWY PLOVERS Sea Beach and Lido Palms (area 4, Figure 2), and 102 were scattered along a 8-km stretch of beach between Iberia Wash and the north boundary of the Salton Sea Naval Test Base (area 6, Figure 2). In 1994 the highest single concentration of 89 plovers was scattered along a 8-km segment of the southeastern shoreline from the Wister Unit of Imperial Wildlife Area south to McDonald Road (area 13, Figure 2). Other southern California sites. During surveys in the winters of 1992- 93, 1993-94, and 1994-95 small numbers of Snowy Plovers were found at three sites in the Mojave Desert and at Lake Elsinore, Riverside County (Appendix 1). A large number of other winter records of Snowy Plovers in southern California have now accumulated; most are from alkali lakes and sewage ponds in the southern Great Basin, Mojave, and Colorado deserts (Appen- dix 2). Northern California. The only Snowy Plover found on our surveys in the Sacramento Valley was a single bird in a flooded fallow agricultural field about 8 km northwest of Colusa, Colusa County, on 25 January 1995 (C. Hickey), We know of no other winter records of Snowy Plovers from the Sacramento Valley. The latest records for the Sierra Nevada and Great Basin Desert, respectively, are of one at the south end of Lake Tahoe, El Dorado County, on 11 November 1961 (G. McCaskie in Page et al. 1986) and one or two at Mono Lake, Mono County, on 6 November 1990 (J. R. Jehl, Jr., pers. comm.). These November records probably represent late migrants rather than true winterers; the winter climate of both locations is typically too severe for overwintering plovers. Arizona and New Mexico. Snowy Plovers winter infrequently in these states. We have found only nine winter records for Arizona, four from the Colorado River, the remaining five from scattered localities, Prescott being the northernmost (Appendix 2). For New Mexico we found five records, excluding the one of 9 at Laguna Grande, Eddy County, on 27 February 1993 (AB 47:287), thought to represent early spring migrants (AB 47:287). Four of the records are from playa lakes in the southeastern corner of the state. Oregon, Nevada , and Washington. Three Snowy Plovers at Harney Lake, Malheur NWR, Harney County, on 27 February 1968 have been considered early spring migrants (Page et al. 1986, Littlefield 1990), but this seems extremely early given the average arrival date of 26 April at Malheur (Littlefield 1990) and the typical late March arrival of plovers inland in southern California and Nevada (see above). This undocumented record is also anomalous since there are no mid-winter records from the interior of California north of the Sacramento and Owens valleys and no winter records at all from elsewhere in the interior of Oregon (J. Gilligan in litt.), Nevada (Alcorn 1988, V. Mowbray pers. comm.), or Washington (B. Tweit pers. comm.). Size of the Interior Wintering Population Our surveys were most complete in November and December 1993 and 1994 when 499 and 283 Snowy Plovers, respectively, were located 88 WINTERING SNOWY PLOVERS wintering in the interior of California: Salton Sea {285, 214), evaporation ponds in San Joaquin Valley (185, 65), Lancaster sewage ponds (17, 2; on CBC), Harper Dry Lake (9, 0), and Grasslands (3, 2). We would likely have found a few more plovers in the interior in 1993 and 1994 if we had surveyed a few other sites in southern California and all suitable habitat in southern Arizona and New Mexico. Habitat Use Snowy Plovers wintering in the San Joaquin Valley were found primarily in evaporation ponds where shallow water was bordered with extensive alkali flats. They tended to forage on the moist alkali flats near the water’s edge and to roost in depressions in raised areas of bumpy encrusted alkali. At the Salton Sea, foraging plovers were most frequent on moist flat beaches >20 m wide. They concentrated particularly on the margins of shallow receding lagoons perched on the beach slope above the main shoreline, often found on the broad deltas of creeks or washes. Plovers tended to roost on encrusted alkali near lagoons or on the barnacle- and driftwood-strewn berms of beaches. We also found plovers at five sets of sewage ponds, but they occurred more or less regularly only at the Lancaster sewage ponds in the Mojave Desert. There they roosted on the gravel- or rock-lined dikes, but it is unclear if they use these sewage ponds extensively for foraging. The five sewage ponds used by plovers are within a few kilometers of either alkaline wetlands (Los Banos sewage ponds), evapora- tion ponds (Lemoore Naval Air Station sewage ponds), or a playa lake (Edwards Air Force Base, China Lake, and Lancaster sewage ponds), habitats that the birds may use as primary or supplementary foraging areas. The bird seen on the 29 December 1985 Creighton Ranch-Corcoran CBC in the southern San Joaquin Valley was on exposed mudflats in a shallowly flooded fallow field (R. Hansen pers. comm.), as was the bird near Colusa in the Sacramento Valley on 25 January 1995 (C. Hickey pers. obs.). Rosenberg et al. (1991) reported that in the lower Colorado River Valley Snowy Plovers are “most frequently observed in plowed agricultural fields,” presumably during migration, but this habitat appears to be very rarely used in winter anywhere in the West. DISCUSSION San Joaquin Valley Our surveys establish that the Snowy Plover currently winters regularly in modest numbers at agricultural evaporation ponds in the southern San Joaquin Valley of California. Most of these ponds were built from the late 1970s to the mid-1980s (Moore et al. 1990) and were rapidly colonized by breeding (Ivey 1984) and wintering (Page et al. 1986) Snowy Plovers. Earlier winter counts of Snowy Plovers at the TLDD Hacienda and TLDD South evaporation ponds combined ranged from 4 to 36 (mean 19.7, SE 4.0) on 7 surveys from 7 November 1983 to 3 January 1984 and from 1 to 7 (mean 3.7, SE 0.6) on 11 surveys from 13 January to 29 February 1984 (H. Coe in litt.). Although the variation in numbers among the four years of our study (Table 1) precludes valid comparisons to the prior single-year 89 WINTERING SNOWY PLOVERS survey, it is clear that the Snowy Plover was well established in winter at least by 1983, five years after the TLDD ponds were built in 1978 (Moore et al. 1990). Surveys of 16 sets of evaporation ponds totaling about 2517 hectares in the winter of 1989-90 yielded totals of 42 birds in early November, 57 in early December, and 73 in early February (R. Marsh in lift.). These counts fall within the range of variation of our 1991-92 to 1994-95 counts (Table 1). These data suggest that the wintering population of plovers on the evaporation ponds is generally smaller than the breeding population. Ros- ter et al. (1992) counted a maximum of 181 adult-sized plovers on 12 sets of evaporation ponds in the breeding season of 1987. Because they did not differentiate between adults and full-grown juveniles and because their counts increased steadily over the breeding season, at a time when young would be fledging continually, their total likely overestimates the adult breeding population that year. Page et al. (1991) reported a raw count of 241 adult plovers on a survey of all evaporation ponds in 1988, but estimated a total of 339, on the basis of suspected low totals from ponds where Snowy Plovers were counted during multi-species surveys. J. Skorupa and D. Barnum (in Page et al. 1991) found 189 adult plovers at six sets of ponds in 1989. The average of our November and January counts (Table 1) implies that the wintering population on these ponds was about 66 in 1991-92, 157 in 1992-93, 148 in 1993-94, and 88 in 1994-95. Because of this variation, a survey of plover numbers over several consecu- tive breeding and winter seasons would be desirable to better establish the relative size of the breeding versus the wintering population. The breeding grounds of the plovers wintering in the interior are un- known. Five Snowy Plovers color-banded as chicks at evaporation ponds in the San Joaquin Valley in 1989 wintered on the California coast in 1989- 90 (Page et al. 1995, PRBO unpubl. data). Also, single color-banded birds sighted on 14 February 1990 at both the TLDD Hacienda and TLDD South evaporation ponds had been banded as young on these ponds in summer 1989 (J. Skorupa in lift.). They may have wintered on these ponds or may have wintered on the coast, returning early to set up for breeding in the San Joaquin Valley. More color-banding would be useful, to determine if some plovers hatched on the evaporation ponds are resident and, if so, what proportion of the population is resident and what proportion migrates to the coast or elsewhere. Very limited information is available on the historical breeding status of the Snowy Plover in the San Joaquin Valley (Page and Stenzel 1981), and even less is known of the species’ former status there in winter (Page et al. 1986). The Tulare Basin historically held the largest single block of wetland habitat in California, primarily in the form of shallow lakes and associated marshes (USFWS 1990). These playa lakes, in a region of high soil alkalinity (Preston 1981), must have provided ideal habitat for both breed- ing and wintering Snowy Plovers. The plover’s use of these lakes went largely undocumented before they were drained. Because of the vast extent of former habitat, we suspect that plover numbers in the Tulare Basin may have rivaled or exceeded those in any other region in the interior of California. 90 WINTERING SNOWY PLOVERS Salton Sea The largest population of Snowy Plovers wintering in the interior of the West is found at the Salton Sea. Lack of prior thorough surveys led Garrett and Dunn (1981) to conclude that the Snowy Plover “rarely” remains at the Salton Sea through winter (K. Garrett pers. comm.) and left Page et al. (1986) unable to estimate the size of the winter population there. Given that the Salton Sea is among the Snowy Plover’s most important breeding areas in the interior of California (Page and Stenzel 1981, Page et al. 1991), that it has long been occupied by breeding birds (Page and Stenzel 1981), and that it has mild winters, it also seems likely that for decades since its creation in the early 1900s it has held a substantial wintering population of plovers. Page et al. (1986) speculated that the wintering population of plovers at the Salton Sea is smaller than the breeding population, but our surveys suggest that the wintering population is similar to or greater than the breeding population. Surveys at both seasons over several years are needed to assess this accurately. Our total of 499 Snowy Plovers in the interior of California in the early winter of 1993 is about 200 more than the estimate by Page et al. (1986) of at most 300. By contrast, our total in 1994 was only 283. Our 1993 total is also about 20% of the 2500 that Page et al. (1986) estimated were wintering along the California coast. Doubtless the interior wintering popu- lation fluctuates as climatic conditions and management practices that affect habitat conditions for the plovers vary. For instance, November counts at two of the three sets of evaporation ponds that held the most birds during our study ranged from 0 to 79 and 0 to 95 over the four years. Our highest count of 95 plovers at the TLDD South evaporation ponds in late Novem- ber 1993 was at a time when the ponds were drawn down for structural alterations, thereby exposing extensive alkali flats (J. Wilson pers. comm.). It would be desirable to improve the estimates of the year-to-year variation in the size of the interior wintering population of Snowy Plovers by conducting more winter counts and by measuring detection rates to account for plovers missed on surveys. Root (1988), using Christmas Bird Count data, mapped the winter distribution of the Snowy Plover in North America and concluded that all populations were in areas that average warmer than 30° F (-1° C) in January. We plotted our more extensive record for the interior of the West on Root’s (1988) contour map of average minimum January temperatures and found that plovers winter at many sites with average minimum January temperatures lower than 30° F (Figure 3). An average minimum January temperature of 20° F (-6° C) is a better temperature threshold, but Snowy Plovers nevertheless do not winter in an extensive area of lowland northern California warmer than this. Knowing that inland plovers concentrate on alkaline soil near saline water, we thought that some measure of aridity might also be helpful in predicting Snowy Plover distribution. This led us to plot winter records of Snowy Plovers in relation to both temperature and general humidity (as measured by pan evaporation rates). The best fit of our data was to an average minimum January temperature warmer than 20° F (-6° C) combined with an average annual pan evaporation rate greater than 91 WINTERING SNOWY PLOVERS Figure 3. (a) Average minimum January temperatures with 10° F (5° C) contour intervals; tick marks point toward lower temperatures (from Root 1988). (b) Average annual general humidity, as measured by pan evaporation, with 20-inch evaporation contour intervals; tick marks point toward smaller values (from Root 1988). (c) Winter (15 Nov- 15 Feb) records of Snowy Plovers in the interior of the West plotted relative to the isolines of 20° F average minimum January temperature and 70 inches average annual pan evaporation (general humidity) (adapted from Root 1988). Large dots, sites of regular wintering; small dots, sites of erratic wintering. 92 WINTERING SNOWY PLOVERS 70 inches (Figure 3c). Thus aridity as well as warmth favors Snowy Plovers. Although the increasing concentration of salts and trace elements, par- ticularly selenium, in the San Joaquin Valley (e.g., Skorupa and Ohlendorf 1991, Ohlendorf et al. 1993) and at the Salton Sea (e.g., Schroeder et al. 1993, Setmire et al. 1993) has impaired the reproduction of some species of birds, to date the risk of toxicity to Snowy Plovers has been low (J. Skorupa pers. comm.). Ironically, Snowy Plovers may face habitat loss as pond owners seek means to reduce the toxicity risk to wildlife using these habitats (see Moore et al. 1990). Methods suggested to reduce bird use of contaminated ponds in the San Joaquin Valley include hazing, altering the pond's physical structure, and creating nearby uncontaminated wetlands as alternative habitat (Steele and Bradford 1991, Bradford 1992). While some such wetlands have already been constructed, both the total amount of alternative habitat and the proportion of freshwater and saline wetlands in it have yet to be decided (C. Taylor pers. comm.). Monitoring to determine the effect of these actions on the health and size of populations of the Snowy Plover and other species will be needed. SUMMARY Surveys over four years reveal that most Snowy Plovers wintering in the interior of the West concentrate in California at agricultural evaporation ponds in the southern San Joaquin Valley and at the Salton Sea. Small numbers of plovers also winter irregularly in deserts elsewhere in southern California, Arizona, and New Mexico, primarily at playa lakes. Surveys in 1993 found 499 Snowy Plovers wintering in the interior of California, about 200 more than had been estimated from prior partial surveys. The wintering population at the Salton Sea appears to be greater than or equal to the breeding population, but the converse appears to be true at evapora- tion ponds in the San Joaquin Valley. The inland distribution of wintering plovers in the West corresponds to arid climates (average annual evapora- tion >70 inches) and mild (average January temperature >-6° C) winters. Changes in management practices at the evaporation ponds designed to reduce the toxic effects of selenium on wildlife using the ponds may in the near future affect the amount and quality of habitat for plovers and other shorebirds. ACKNOWLEDGMENTS Major funding for the Pacific Flyway Project was provided by the Bay Foundation of Morro Bay, the Bradford Foundation, the Bureau of Reclamation, the Central Valley Habitat Joint Venture, Chevron USA Inc., the Dakin Foundation, the David and Lucille Packard Foundation, the Dean Witter Foundation, Ducks Unlimited, Genentech, the Walter and Elise Hass Fund, the Marin, Morro Coast, and Stockton chapters of the National Audubon Society, the National Fish and Wildlife Foundation, the San Francisco Foundation, the Strong Foundation, and the True North Founda- tion. The Pacific Flyway Project has become a cooperative venture on a grand scale, and we are grateful to all who have supported our work in any way. At the risk of 93 WINTERING SNOWY PLOVERS inadvertently leaving out important contributors, we particularly thank the following groups and individuals that helped organize shorebird counts in the San Joaquin Valley and southern California deserts, which provided data on the status of wintering Snowy Plovers in these regions: San Joaquin Valley — Bob Barnes, Doug Barnum, John Beam, Calif Dept. Fish and Game (CDFG), Steve Clay, Mark Chichester, Joe Engler, Sam Fitton, Greg Gerstenberg, Ron Gerstenberg, Grasslands Water District, Rob Hansen, H. T Harvey and Assoc., Greg and Karen Kirkpatrick, Tim Kroeker, Mike Peters, Tim Poole, Gary Potter, Martin Potter, Harold Reeve, Jeff Seay, Mark Stacy, Charles Stearns, U. S. Fish and Wildlife Service (USFWS) at San Luis NWR complex and Kern NWR, Bruce Williford, John Wilson, Dennis Woolington, and Gary Zahm; southern California deserts — Bert Anderson, David Blue, Eugene Cardiff, Barbara Carlson, Dave Feliz, Kirnball Garrett, Matt Heindel, Tom and Joe Heindel, Robert McKernan, Susan Nash, Michael Patten, Michael Prather, and USFWS at Salton Sea NWR. We would particularly like to thank the numerous landowners and land managers that have graciously allowed access to their lands, without which our studies would not have been possible. The following individuals and organizations kindly shared their unpublished records of Snowy Plovers: CDFG, Eugene Cardiff, Rob Hansen, Matt Heindel, Tom and Jo Heindel, H. T. Harvey and Assoc., Gale Monson, Jan Tarble, Rex Marsh, Terry Salmom, and Todd Sloat. Brett Hoover of the National Biological Survey promptly provided computerized CBC data for the western states. Doug Barnum, Fred Heath, Kimball Garrett, Jeff Gilligan, Vince Mowbray, Michael Patten, Philip Unitt, Bill Tweit, and Sartor O. Williams III freely shared their knowledge of Snowy Plovers. Helen Green provided Snowy Plover records from the files of the editors of the Middle Pacific Coast Region of American Birds on file at Golden Gate Audubon Society in Berkeley. Janet Kjelmyr summarized Snowy Plover data from PRBO's Pacific Flyway Project surveys. Peter Paton and Philip Unitt provided very helpful reviews of an earlier draft of the manuscript. This is Contribution No. 641 of PRBO. LITERATURE CITED Alcorn, J. R. 1988. The Birds of Nevada. Fairview West, Fallon, NV. Bradford, D. F. 1992. Potential sites and mechanisms for creating wetland habitat in the southern San Joaquin Valley. Final Report for Calif. Dept. Water Resources, 1025 P St., Sacramento, CA 94236. Fisher, A. K. 1893. Report on the ornithology of the Death Valley expedition of 1891, comprising notes on the birds observed in southern California, southern Nevada, and parts of Arizona and Utah. N. Am. Fauna 7. Garrett, K., and Dunn, J. 1981. Birds of Southern California: Status and Distribu- tion. Los Angeles Audubon Soc., Los Angeles. Halpin, M., and Paul, D. 1989. Survey of Snowy Plovers in northern Utah — 1988. Utah Birds 5:21-32. Henderson, R. P, and Page, G. W, 1979. Part III: The California interior, in The breeding status of the Snowy Plover in California (G. W. Page and L. E. Stenzel, eds.), pp. III-l to III-41. Nongame Wildlife Invest. Rep., Calif. Dept. Fish Game, Sacramento. Herman, S. G., Bulger, J. B., and Buchanan, J. B. 1988. The Snowy Plover in southeastern Oregon and western Nevada. J. Field Ornithol. 59:13-21. Ivey, G. L. 1984. Some recent nesting records for the Snowy Plover in the San Joaquin Valley, California. W. Birds 15:189. 94 WINTERING SNOWY PLOVERS Littlefield, C. D. 1990. Birds of Malheur National Wildlife Refuge, Oregon. Ore. State Univ. Press, Corvallis. Monson, G., and Phillips, A. R. 1981. Annotated Checklist of the Birds of Arizona, 2nd ed. Univ. Ariz. Press, Tucson. Moore, S. B., Winckel, J., Detwiler, S. J., Klasing, S. A., Gaul, P. A., Kanim, N. R., Kesser, B. E., DeBevec, A. B., Beardsley, K., and Puckett, L. K. 1990. Fish and wildlife resources and agricultural drainage in the San Joaquin Valley, California. Report of the San Joaquin Valley Drainage Program, 2800 Cottage Way, Rm. W-2143, Sacramento, CA 95825-1898. Ohlendorf, H. M., Skorupa, J. P., Saiki, M. K., and Barnum, D. A. 1993. Food- chain transfer of trace elements to wildlife, in Management of Irrigation and Drainage Systems: Integrated Perspectives (R. G. Allen and C. M. U. Neale, eds.}, pp. 596-603. Proceedings of the 1993 National Conference on Irrigation and Drainage Engineering, Park City, Utah; July 21-23, 1993. Am. Soc. Civil Engineers, 345 East 47th St., New York, NY 10017-2398. Page, G. W., Bidstrup, F. C., Ramer, R. J., and Stenzel, L. E. 1986. Distribution of wintering Snowy Plovers in California and adjacent states. W. Birds 17:145- 170. Page, G. W., and Stenzel, L. E., eds. 1981. The breeding status of the Snowy Plover in California. W. Birds 12:1-40. Page, G. W., Stenzel, L. E., Shuford, W. D., and Bruce, C. R. 1991. Distribution and abundance of the Snowy Plover on its western North American breeding grounds. J. Field Ornithol. 62:245-255. Page, G. W., Stern, M. A., and Paton, P. W. C. 1995. Differences in wintering areas of Snowy Plovers from inland breeding sites in western North America. Condor 97:258-262. Phillips, A., Marshall, J., and Monson, G. 1964. The Birds of Arizona. Univ. Ariz. Press, Tucson. Preston, W. L. 1981 , Vanishing Landscapes: Land and Life in the Tulare Lake Basin. Univ. Calif. Press, Berkeley. Root, T. 1988. Atlas of Wintering North American Birds: An Analysis of Christmas Bird Count Data. Univ. Chicago Press, Chicago. Rosenberg, K. V., Ohrnart, R, D,, Hunter, W. C., and Anderson, B. W. 1991. Birds of the Lower Colorado River Valley. Univ. Ariz. Press, Tucson. Roster, D. L., Hohrnan, W. L., and Barnum, D. A. 1992. Use of agricultural drainwater impoundments by Snowy Plovers ( Charadrius alexandrinus nivosus) in the southern San Joaquin Valley, California, in Endangered and sensitive species of the San Joaquin Valley, California: Their biology, manage- ment, and conservation (D. F. Williams, S. Byrne, and T. A. Rado, eds.), pp. 229-235. Calif. Energy Comm., 1516 Ninth St., Sacramento, CA 95814. Schroeder, R. A., Rivera, M., Redfield, B. J., Densmore, J. N., Michel, R. L., Norton, D. R., Audet, D. J., Setmire, J. G., and Goodbred, S. L. 1993. Physical, chemical, and biological data for detailed study of irrigation drainage in the Salton Sea area, California, 1988-90. U. S. Geol. Surv. Open-File Rep. 93-83. U. S. Geol. Surv., Federal Bldg., Rm. W-2233, 2800 Cottage Way, Sacra- mento, CA 95825. Setmire, J. G., Schroeder, R. A., Densmore, J. N., Goodbred, S. L., Audet, D. J., and Radke, W. R. 1993. Detailed study of water quality, bottom sediment, and biota associated with irrigation drainage in the Salton Sea area, California, 95 WINTERING SNOWY PLOVERS 1988-90. U. S. Geol. Surv. Water-Resources Invest. Rep. 93-4014. U. S. Geol. Surv., Federal Bldg., Rm. W-2233, 2800 Cottage Way, Sacramento, CA 95825. Skorupa, J. P. s and H. M. Ohlendorf. 1991. Contaminants in drainage water and avian risk thresholds, in The Economics and Management of Water and Drain- age in Agriculture (A. Dinar and D. Zilberman, eds.), pp. 345-368. Kluwer Academic, Norwell, MA. Steele, N. L. C., and D. F. Bradford. 1991. Habitats, siting, and management of potential wetlands in the southern San Joaquin Valley, California. ESE Rep. 91- 07, Calif. Dept. Water Resources, 1025 P St., Sacramento, CA 94236. U. S. Fish and Wildlife Service. 1990. Central Valley Habitat Joint Venture Imple- mentation Plan: A Component of the North American Waterfowl Management Plan. U. S. Fish and Wildlife Serv., 2233 Watt Ave., Suite 375, Sacramento, CA 95825-0509. Wilson-Jacobs, R., and Meslow, E. C. 1984. Distribution, abundance and nesting characteristics of Snowy Plovers on the Oregon coast. Northwest Sci. 58:40- 48. APPENDIX 1 Inland Winter Records of Snowy Plovers in California from This Study, 1991-92 to 1994-95, Other Than From Evaporation Ponds in the San Joaquin Valley (Table 1) or the Salton Sea (Table 2). Survey Sites and Frequency Sites in the San Joaquin Valley surveyed in January 1992, 1993, and 1994, January to February 1995, and November 1993 and 1994: the Grasslands wetlands complex of public wildlife refuges [San Luis NWR, Kesterson NWR, Merced NWR, Arena Plains NWR, Volta Wildlife Area (WA), Los Banos WA, Mud Slough WA, Salt Slough WA, China Island WA] and private duck clubs (two-thirds of the wetland area of the Grasslands) surrounding Los Banos, Merced Co.; Mendota WA, Fresno Co.; Pixley NWR, Tulare Co.; Kern NWR, Kern Co.; South Wilbur Rood Area, Kings Co.; and most sets of municipal sewage ponds and irrigation district ponds from Modesto, Stanislaus Co., south to Bakersfield, Kern Co. Sites in the deserts of southern California surveyed in the winters of 1992-93, 1993-94, and 1994-95: Tinnemaha Reservoir, Inyo Co. (2 Dec 1994, 29 Jan 1995), Owens Lake, Inyo Co. (4 Dec 1993, 29 Jan 1994, 3 Dec 1994, 28 Jan 1995), China Lake sewage ponds, Kern Co. (2 Nov 1992, 23 Jan 1993, 3 Dec 1993, 2 Dec 1994, 28 Jan 1995), Edwards Air Force Base sewage ponds, Kern Co. (27 Nov 1992, 1 Feb 1995), Piute Ponds, Los Angeles Co. (23 Nov 1992, 2 Feb 1993, 3 Dec 1993, 30 Jan 1994), Lancaster sewage ponds, Los Angeles Co. (20 Nov 1992, 2 Feb 1993, 3 Dec 1993, 30 Jan 1994), Harper Dry Lake, San Bernardino Co. (6 Dec 1992, 1 Feb 1993, 5 Dec 1993, 12 Feb 1993, 11 Dec 1994), San Jacinto Valley, Riverside Co. (20 Nov 1992, 30 Nov 1993, 29 Jan 1994, 3 Dec 1994, 29 Jan 1995), Lake Elsinore, Riverside Co. (10 Dec 1993, 6 Feb 1994, 3 Dec 1994, 28 Jan 1995), and agricultural lands south of Blythe, Riverside Co. (8 Dec 1993). Snowy Plover Records Merced Co.: Duck clubs in Grasslands wetlands complex surrounding Los Banos, 3, 20 Nov 1993 (D. Shuford, C. Hickey); 5, 20 Jan 1991 (G. Page); 23, 8 & 11 Feb 1995 (C. Alexander, C. Hickey, H. Reeve, D. Shuford). Los Banos sewage ponds, 2, 9 Nov 1994 (D. Shuford). 96 WINTERING SNOWY PLOVERS Kings Co.: Small alkali ponds near Corcoran Irrigation District reservoir, Corcoran, 1, 28 Jan 1992 (J. Kjelmyr). Westlake Farms section 16 mitigation wetlands, 2.5 km E of Kettleman City, 2, 16 Feb 1995 (J. Seay). Lemoore Naval Air Station sewage ponds (formerly Carlton Duty evaporation ponds), 11, 14 Nov 1994; 9, 31 Jan 1994 (both T. Kroeker). Kern Co.: Edwards Air Force Base sewage ponds, 1, 27 Nov 1992 (M. Heindel). Los Angeles Co.: Lancaster sewage ponds, 20, 20 Nov 1992 (D. Shuford); 3, 3 Dec 1993 (K. Ganett); 9, 2 Feb 1993 (K. Garrett). San Bernardino Co.: Harper Dry Lake, 9, 5 Dec 1993; 6, 6 Dec 1992 (E. Cardiff). Riverside Co.: Lake Elsinore, 1, 6 Feb 1994 (M. A. Patten). APPENDIX 2 Inland Winter Records of the Snowy Plover Other Than Those Generated by This Study California Merced Co. Los Banos sewage ponds, 1, 26 and 27 Dec 1986 (AB 41:324); 2, 28 Dec 1992 (AB 47:949) Kern Co.: Lake Isabella, 1, 25 Jan 1985 (AB 39:210). Carmel Ranch evaporation ponds (Figure 1), 5, 24 Nov 1990 (M. Heindel). China Lake sewage ponds, 1, 21 Dec 1990 (D. Blue). Edwards Air Force Base sewage ponds, 1, 23 Nov 1991; 5, 22 Dec 1990; 6, 30 Dec 1989; 8, 4 Jan 1989 (all M. Heindel). Inyo Co. (all Owens Lake): “Northwest Seep,” 1, 15 Dec 1984 (AB 39:785, D. Gaines); 9, 20 Dec 1986 (AB 41:1270). Keeler saltworks, 1, 20 Dec 1993 (NASFN 48:248); 2, 11 Jan 1976; 11, 28 Jan 1993; 3, 2 Feb 1993 (all T. & J. Heindel). Cottonwood Marsh, 16 km SSE of Lone Pine, 4, 23 Dec 1992 (M. Heindel, T. & J. Heindel). Exact location not recorded, 1, 27 Dec 1890 (Fisher 1893). Dirty Sock Springs, 2, 3 Jan 1975 (AB 29:742). Los Angeles Co.: Lancaster sewage ponds. 10, 14 Dec 1991 (AB 46:977); 2,17 Dec 1994 {fide Fred Heath); 17, 18 Dec 1993 (NASFN 48:833); 6, 19 Dec 1992 (AB 47:948). Rosamond Lake, 1, at least Dec 1981 through Feb 1982 (AB 36:331); 2, 15 Dec 1984 (AB 39:785); 26, 17 Dec 1983 (AB 38:789). San Bernardino Co.: Harper Dry Lake, 4, 21 Nov 1988; 6, 23 Nov 1987; 5, 10 Dec 1988; 4, 27 Feb 1988 (all E. Cardiff). East Cronese Lake near Baker, 1, 19 Nov 1978 (AB 33:213). Riverside Co.: Lake Elsinore, 6, 11 Dec 1981 (Page et al. 1986); 10, 30 Jan 1982 (AB 36:331). San Diego Co.: Lake Henshaw, 1, 5 Nov 1978 (AB 33:213). Lake Hodges, 2-3, during winter 1979-80 (Garrett and Dunn 1981); 2, 6 Nov 1982 (Page et al. 1986). Imperial Co.: West Pond, below Imperial Dam, 4, 23 Dec 1961 (W. C. Royall, Jr. and L. Olver fide G. Monson). We have rejected the following records for lack of sufficient documentation: Los Angeles Co., “at reservoir” on the Pasadena-San Gabriel Valley CBC, 6, 29 Dec 1964 (AFN 19:331); Orange Co., Irvine Lake on the Orange Co. (northeastern) CBC, 20, 4 Jan 1981 (AB 35:721). 97 WINTERING SNOWY PLOVERS Arizona Mohave Co.: Lake Havasu, 1, 20 Jan 1982 (AB 36:318). Mohave and La Paz counties: Bill Williams R. delta, 2, 20 Oct 1952 to 7 Mar 1953 (G. Monson). Yuma Co.: Martinez Lake, 1, 2 Feb 1977 {S. Furniss, USFWS, fide G. Monson). 1.5-3 km north of Imperial Dam, 1-2, 4 Nov 1960 to 1 Feb 1961 (G. Monson). Yavapai Co.: Willow Lake, Prescott, 1, 24 Nov 1985 (AB 40:151). Maricopa Co.: Phoenix, 1, 28 Dec 1963 (AFN 18:295, Monson and Phillips 1981). Near Gila Bend on Gila River, 7, 15 Jan 1974 (AB 28:674). Pima Co.: Tucson, 1-2, 11 Oct to 3 Dec 1971 (AB 26:101). Cochise Co.: Willcox, 1, 31 Dec 1976 (AB 31:359). New Mexico Sierra Co.: Elephant Butte Lake, 1, 14 Jan 1990 (P. Steel fide N. M. Ornithol. Soc. Field Notes 29:6). Otero Co.: Holloman Lakes, 1, 23 Feb 1985 (AB 39:198). Eddy Co,: Laguna Grande, 1, 28 Dec 1976 (AB 31:359); 1, 4 Jan 1987 (AB 41:315). Vicinity of Salt Lake, east of Loving, 1-2, 9-27 Jan 1975 (AB 29:725). Accepted 23 March 1 995 98 NOTES BREEDING BIRDS OF ESTEROS T6BARI AND SAN JOSE, SOUTHERN SONORA EDUARDO PALACIOS and ERIC MELLINK, Centro de Investigacion Cient'ifica y Educacion Superior de Ensenada, Apdo. Postal 2732, Ensenada, Baja California, Mexico or P. O. Box 434844, San Diego, California 92143 Although the ornithofauna of Sonora has been studied since, at least, the 19th century (van Rossem 1945), it is still rather poorly known. This is particularly true for its southern coastal area. Van Rossem and Hachisuka (1937) provided an extensive list of water birds from Estero Tobari but found little evidence of local breeding for most species. In 1971 and 1972, Knoder et al. (1980) made aerial surveys of water birds and wetlands along the coasts of Baja California and the west coast of mainland Mexico, from the delta of the Rio Colorado to San Bias, Nayarit, but did not include Estero Tobari as one of their intensively surveyed sites. Here we report on the breeding birds that we recorded on a trip to esteros Tobari (including Isla Huivulai) and San Jose on 14 May 1994 (Figure 1). In Estero Tobari, we surveyed the north and south mouths of the bay, two islets outside the north mouth, and two heronries on the southeast and northwest sides of Isla Huivulai. San Jose is a small fishermen’s town 8 km northwest of the north mouth of Estero Tobari, with an estero and a large saltflat nearby, both of which we surveyed. We visited also an abandoned shrimp farm at the north end of Estero Tobari. The main purpose of our trip was to search for Least Tern breeding colonies. Great Blue Heron (Ardea herodias). A heronry in NE Isla Huivulai contained eight nests, one with two half-grown chicks. On the west coast of mainland Mexico, Great Blue Herons breed from the delta of the Rio Colorado (Palacios and Mellink 1993) south to, at least, San Bias, Nayarit (Knoder et al. 1980). Griffing Bancroft (unpublished field notes) had found this species as a breeder at Estero Tobari in 1930, and van Rossem and Hachisuka (1937) collected a specimen in breeding condition from there. Great Egret ( Casrnerodius albus). Two heronries in SE and NE Huivulai had about 15 pairs with nests each. Van Rossem and Hachisuka (1937) had recorded this species as a breeder from the area. Snowy Egret ( Egretta thula). There were 20 pairs in the SE heronry and about the same number in the NE heronry on Isla Huivulai. The Snowy Egret is reported as occurring along the Pacific coast of Mexico from Puerto Penasco south to the Istmo de Tehuantepec (Knoder et al. 1980) and being a resident from Guaymas south (van Rossem 1945), but no previous breeding records exist for southern Sonora. Little Blue Heron ( Egretta caerulea). We found three pairs with nests in each heronry on Isla Huivulai. This species is known to occur from Punta Sargento south to the Istmo de Tehuantepec (Knoder et al. 1980) and to be a summer resident of the mangrove association of southern Sonora (van Rossem 1945), but no particular breeding locations had been published. Tricolored Heron ( Egretta tricolor ). We saw five adults feeding on the mudflat in front of the heronry in NE Isla Huivulai; we presume nesting. Like previous species, this heron has been noted from Guaymas south to Tehuantepec (Knoder et al. 1980) and to be a resident of coastal lagoons in southern Sonora (van Rossem 1945), but no specific breeding locations had been provided. Western Birds 26:99-103, 1995 99 NOTES Reddish Egret { Egretta rufescens). We found three pairs with nests in each heronry on Isla Huivulai. This species ranges from Puerto Penasco to Tapachula, Chiapas (Knoder et al. 1980). Bancroft (unpublished field notes) found this species breeding at Estero Tobari, and van Rossem and Hachisuka (1937) collected a specimen in breeding condition there. Cattle Egret ( Bubulcus ibis). About 100 pairs were nesting in each heronry of Isla Huivulai. This is the second breeding record for Sonora of this still-expanding species (see Mellink and Palacios 1993). Green Heron ( Butorides virescens). We found one pair on a nest in the SE heronry, and five pairs with nests in the NE heronry. This secretive species, which is often overlooked and underestimated, was collected in breeding condition at Estero Tobari by van Rossem and Hachisuka (1937). Black-crowned Night-Heron ( Nycticorax nycticorax). We found three pairs nest- ing in the SE heronry and several individuals, with no evidence of nesting, in the NE heronry. There were one adult and one immature in nearby agricultural drains. This species is often overlooked, even from the ground. Therefore, very likely there were more individuals in the area. Bancroft found a nest with three eggs on Isla Huivulai on 11 June 1930 (deposited at the Western Foundation of Vertebrate Zoology [WFVZ]), and van Rossem (1945) reported it as a resident on “suitable . . . localities” throughout the state. Yellow-crowned Night-Heron (Nycticorax violaceus). We found 20 pairs with nests and one immature in the SE heronry and 20 pairs with nests in the NE heronry on Isla Huivulai. One hundred thrity individuals (including 2 immatures) were foraging throughout the bay and in nearby drains. Bancroft collected nests from apparently four sites on Isla Tobari [=HuivuIai] in Estero Tobari on 27 April 1930 (6 sets of eggs deposited at WFVZ). Van Rossem (1945) reported this species as a local resident on coastal lagoons. White Ibis (Eudocimus albus). The SE heronry of Isla Huivulai had 100 adults, including 37 nesting pairs. The NE heronry had about the same number. We found 20 adults and three immatures at Paredon Colorado, in the central part of Estero Tobari. The species occurs from Guaymas south to the Istmo de Tehuantepec (Knoder et al. 1980) and has been reported in spring and summer from Estero Tobari (van Rossem 1945). In May 1930 Bancroff took eggs from two nearby locations, Laguna Guasimas and Isla Lobos (deposited at WFVZ). Roseate Spoonbill ( Ajaia ajaja). We found 15 pairs with nests in the SE heronry. There were none in the NE heronry. Knoder et al, (1980) found this species from Los Mochis south to the Istmo de Tehuantepec, and the AOU (1983) considered it a resident only from northern Sinaloa south. This is the first breeding record for Sonora. Common Moorhen (Gallinula chloropus). We saw three broods (2 or 3 chicks per brood for 8 chicks; 4 adults) in various agricultural drains near Estero Tobari. Snowy Plover ( Charadrius alexandrinus). On the San Jose saltflat there was one pair calling and performing a distraction display, and one empty shell-lined nest. There was one adult at Paredon Colorado and one adult on the islets at the northern mouth of Estero Tobari. No previous nesting records of this species in Sonora have been published, and the AOU (1983) did not include Sonora within the breeding range of this species. Wilson’s Plover (Charadrius wilsonia). We saw 20 pairs in Estero de San Jose; all birds were calling and performing distraction displays, including broken-wing behav- ior; one adult had a chick less than a week old. Five pairs were on the saltflat near San Jose. One adult performed distraction behavior at the abandoned shrimp farm north of Estero Tobari. An eggshell found near this site by M. Tordecillas (pers. comm.), 5 May 1994, probably was from this species. 100 NOTES 101 Figure 1. Estero Tobari, including Isla Huivulai, and San Jose, with its associated estero and saltflat. NOTES American Oystercatcher ( Haematopus paUiatus). There were six pairs nesting on the shell dump south of El Paredoncito (also named El Tobari), at the south side of Estero Tobari; one of the birds performed attraction display. There was one pair on a tiny islet in front of El Paredoncito, six pairs, one with three eggs, on the islets outside the north mouth of the bay, and two pairs on the north end of Isla Huivulai. At the Estero de San Jose there were three pairs, one with three chicks, and at the San Jose saltflat, two pairs, of which one individual performed pseudo-incubation. Least Tern (Sterna antillarum). We found five aggregations of this species: south side of the south mouth of the bay (82 adults), north side of the north mouth of the bay (34 adults), islet outside the north mouth of the bay (28 adults), Estero de San Jose (15 pairs nesting; 4 nests had 2 eggs each and 1 nest, 1), and San Jose saltflat (15 pairs nesting; 3 nests had 2 eggs each). Although, we confirmed nesting only at San Jose, the birds looked like they were nesting on the islet outside the north mouth. There is a chance that this colony was wiped out by the high tides preceding our visit. Conservation of these colonies of Least Terns is important because, being at the type locality of S. a. mexicana, they are relevant to the taxonomic status of Least Terns in northwestern Mexico. Black Skimmers ( Rgnchops niger ) We found 50 adults together with Black Terns (Chlidonias niger ) on the islet of the north mouth. There were nest-like depressions in the sand, but no definite evidence of nesting. Van Rossern and Hachisuka (1937) indicated that “it was perfectly evident that the breeding season was at hand,” although they too failed at finding nests. White-winged Dove (Zenaida asiatica). We heard several singing in both heronries but did not search for evidence of nesting. Other resident species that we observed and that probably nest in the area, but for which we found no evidence, include five pairs of ducks resembling Mexican Ducks (Anas diazi) in nearby drains (it is likely that they are feral domestic ducks), Clapper Rail ( Rallus longirostris ; 1 in the NE heronry), Black-necked Stilt ( Himantopus mexicanus ; 7 adults on one of the islets outside the northern mouth of the bay; 5 elsewhere in the bay), Killdeer ( Charadrius uociferus ; 5 adults throughout the bay), Savannah Sparrow ( Passerculus sandwichensis; several near El Paredoncito). On the other hand, it was somehow surprising not finding any Wood Storks ( Mycteria americana), which were reported as common by van Rossern and Hachisuka (1937), nor any Black-bellied Whistling-Ducks (Dendrocggna autumnalis), which are resi- dent from central Sonora south (AOU 1983) and abundant in the area (L. A. Moreno-Matiella pers. comm.). On the whole, the local breeding bird community is more similar to communities in northern Sinaloa (e.g., Knoder et al. 1980, Carmona and Danemann 1994) than to those in northern Sonora (Mellink and Palacios 1993). This is not surprising, as the heronries of Estero Tobari were found in mangroves, like those in northern Sinaloa, rather than in Sonoran desert scrub ( sensu Brown and Lowe 1980) as to the north. We observed also several late migrants or oversummering coastal birds, through- out the area: Black-bellied Plover ( Pluuialis squatarola; 3), Marbled Godwit ( Limosa jedoa-, 1000), Whimbrel (Numenius phaeopus; 20), Long-billed Curlew ( Numenius americanus; 3), Willet ( Catoptrophorus semipalmatus; 4), dowitcher (Limnodromus spp.; 750), Sanderling (Calidris alba ; 56), Western Sandpiper (Calidris mauri ; 400), Black Tern (33 adults and 4 first-spring birds on one of the islets outside the northern mouth of the bay; 6 adults in Estero de San Jose, overflying the Least Tern colony), and Laughing Gull (Larus atricilla ; 2 in Estero de San Jose). Of these, the Whimbrels and Black Terns had not been reported for this area. Contrasting our data with that of Knoder et al. (1980) shows that mangrove- associated birds are easily overlooked and underestimated from the air (see also Carmona and Danemann 1994). Sampling from the ground should be a regular 102 NOTES complement of aerial surveys, at least of those over heavily vegetated habitats, like mangroves. Our visit to the area was too short to disclose the threats to the nesting birds. However, some points should be made. Villa-lbarra and Ibarra-Gamez (1993) con- cluded that water discharge from the nearby “La Atanasia” shrimp farms could cause excessive plant growth or eutrophication in the Estero de San Jose, and determined that a nearby collector discharging into the same estero was a source of coliform bacteria. Although fishing is intense, we did not see any direct effects on the birds. Isla Huivulai receives visitors who can drive as far as one of the mangroves, although this does not seem to happen very often. There are some potential threats from the agriculture that is practiced in the Valle del Yaqui, one of Mexico’s main “Green Revolution” areas. This agriculture connects with Estero Tobari through a series of drains that discharge into it. The most obvious threat would come from the pesticides that are heavily used in local farming. Also, chances are that discharge of sediments has increased and that these sediments are not being removed by tidal currents, which the causeway linking Isla Huivulai might disrupt. This article greatly benefited from comments made by Gale Monson and Philip Unitt. We thank Miguel Angel Elizalde for transportation to the islands, Marisol Tordecillas for kindly sharing information with us, and Walter Wehtje and Clark Sumida for providing the museum records at WFVZ. Salvador Gonzalez and Fran- cisco J. Ponce assisted in typescript preparation. This work was made possible by a grant from the Consejo Nacional de Ciencia y Tecnologia (CONACYT), Mexico, to Eric Mellink. LITERATURE CITED American Ornithologists’ Union. 1983. Checklist of North American Birds. 6th ed. Am. Ornithol. Union, Lawrence, KS. Brown, D. E., and Lowe, C. H. 1980. Biotic communities of the Southwest. Gen. Tech. Rep. RM-78. Rocky Mountain For. Range Exp. Sta. Map. Carmona, R., and Danemann, G. D. 1994. Nesting waterbirds of Santa Maria Bay, Sinaloa, Mexico, April 1988. W. Birds 25:158-162. Knoder, E,, Plaza, P., and Sprunt, A. 1980. Status and distribution of the Jabiru Stork and other waterbirds in western Mexico, in The Birds of Mexico: Their Ecology and Conservation (P. Schaeffer and S. Ehlers, eds.), pp. 58-127. Proc. Nat. Audubon Soc. Symp. Mellink, E., and Palacios, E. 1993. Notes on the breeding coastal waterbirds in northwestern Sonora. W. Birds 24:29-37. Palacios, E., and Mellink, E. 1993. Additional records of breeding birds from Montague Island, northern Gulf of California. W. Birds 24:259-262. Van Rossem, A. J. 1945. A distributional survey of the birds of Sonora, Mexico. Occas. Pap. Mus. Zool., La. State Univ. 21. Van Rossem, A. J., and the Marquess Hachisuka. 1937. A further report on birds from Sonora, Mexico, with descriptions of two new races. Trans. San Diego Soc. Nat. Hist. 8:321-336. Villa-lbarra, M., and Ibarra-Gamez, J.C. 1993. Estudio preliminar de la calidad del agua en el parque camaronicola “La Atanasia” y efecto de la descarga de sus efluentes a) Estero de San Jose. Bole tin Humedales Costeros de Mexico 1(3): 18-19. 103 NOTES CASSIN’S SPARROW NESTING IN WYOMING ROBERT D. DORN and JANE L. DORN, Box 1471, Cheyenne, Wyoming 82003 Cassin’s Sparrow ( Aimophila cassinii ) was first reported in Wyoming on 8 June 1978 near Columbine, northeastern Natrona County, in the central part of the state (Faanes et al. 1979). Another was reported in 1989 east of Glendo Reservoir in Platte County (Bill Hayes pers. comm.). On 28 June 1990, William Howe of the U. S. Fish and Wildlife Service found four singing males east of Torrington in Goshen County near the Nebraska border (Ritter 1990, Kingery 1990, Scott 1993). Singing males were reported annually from the same area from 1991 (Ritter 1991, Kingery 1991) through 1994 (O. K. Scott in litt). We had been studying the vegetation of this area since 1986 but always too early or too late in the season to see or hear these sparrows. In 1993, we scheduled our work in this area periodically throughout the summer and planned to watch for the sparrows. On our first visit of 1993, on 13 June, we did not see or hear any Cassin’s Spairows, but on our second visit, on 22 June, we observed several singing males. We continued to see singing males on subsequent visits: 27 June and 17, 24, and 31 July. On 31 July, while driving down a little-used trail 6.5 km east northeast of Torrington (T24N, R60W, north half of the north half of section 6), where we earlier had observed a singing male, we flushed an adult with insects in its beak. We immediately stopped the vehicle, hoping to observe an adult feeding young. In a few minutes, the adult reappeared and landed about 25 m in front of us. A few minutes later, we saw the adult sneaking through the brush about 10 m from the vehicle. It then went behind us and finally we heard young being fed, but we were unable to pinpoint the location. The same pattern of feeding continued for about 2 hours, but we still could not locate the young or determine if they were in the nest or not. Finally, we decided to rush in the direction of the feeding on the next visit of an adult. When we did, the adult flushed from within 1 m of the rear of the vehicle. On examining the brush here, we immediately found the nest, which contained three feathered young and one unhatched egg. On being discovered, the young (Figure 1) promptly abandoned the nest and ran into the surrounding brush. The nest measured 90 x 100 mm outside diameter, 70 x 64 mm inside diameter, and 50 mm deep (Figure 2). It was lined with fine grass. The egg was white with no markings (Figure 2) and measured 19 x 16 mm. The nest was about 15 cm above the ground in a Sand Sagebrush ( Artemisia filifolia). This appears to be the first record of the Cassin’s Sparrow nesting in Wyoming. The habitat here is largely consolidated rolling sandhills with the relief averaging about 15 meters. We estimated total vegetation cover at 60%. The most conspicuous plant is Sand Sagebrush. It averages about 5 dm high, and we estimated its cover at about 30%. Other common species include the Prairie Sandreed (Calamouilfa longifolia), Sand Bluestem ( Andropogon hallii ), Prickly Muhly ( Muhlenbergia pungens), Blowout Grass (Redfieldia ftexuosa), Spanish Bayonet ( Yucca glauca ), and Red-fruit Prickly Pear (Opuntia macrorhiza). Andrews and Righter (1992) and Rosche (1994) reported this same habitat for the species in Colorado and Nebraska, respectively. On 15 August, we again visited the area and observed one adult with one juvenile and another single juvenile. On 28 August, we observed several adults and several independent juveniles in small loose feeding flocks with Brewer’s ( SpizelJa brewer i), Chipping (S. passerina ), Clay-colored (S. pallida), and Vesper (Pooecetes gramineus ) sparrows and Lark Buntings ( Calamospiza melanocorys). On 12 Sep- tember, we saw no Cassin’s Sparrows, but the other species that we observed on our previous visit were still there. During the nesting season, the only sparrows that we Western Birds 26:104-106, 1995 104 NOTES Figure 1. Young Cassin’s Sparrow that abandoned the nest on discovery, 31 July 1993, Goshen County, Wyoming. Figure 2. Cassin’s Sparrow nest in Sand Sagebrush with one unhatched egg, 31 July 1993, Goshen County, Wyoming. Three feathered young abandoned the nest on discovery. 105 NOTES saw in the area were the Grasshopper ( Ammodramus savannarum ), Lark (Chondeste s grammacus), and Vesper and Lark Bunting. The Spizellae observed in August and September represent transients. In 1994, we searched for Cassin’s Sparrows in other areas of Sand Sagebrush in Goshen and Platte counties, Wyoming, but we found none, No other areas had this community as well developed as where the sparrows were nesting. Faanes et al. (1979) reported a northward range extension of Cassin’s Sparrows into Nebraska and South Dakota beginning about 1974. The colony in Goshen County, Wyoming, may date from approximately that time. LITERATURE CITED Andrews, R., and Righter, R. 1992. Colorado Birds. Denver Mus. Nat Hist., Denver. Faanes, C. A., Hanson, B. A., and Kantaid, H. A. 1979, Cassin’s Sparrow — First record for Wyoming and recent range extensions. W. Birds 10:163-164. Kingery, H. E, 1990. The nesting season. Mountain West region. Am. Birds 44:1161-1164. Kingery, H. E, 1991. The nesting season. Mountain West region. Am. Birds 45:1141-1144. Ritter, S. 1990. Field notes. Drumming Post (Wyo. Game and Fish Dept.) 3(4):8. Ritter, S. 1991. Field notes. Drumming Post (Wyo. Game and Fish Dept.) 4(3):3. Rosche, R. C. 1994. Birding in western Nebraska. Part II. Birding 26:416-423. Scott, O. K. 1993. A Birder’s Guide to Wyoming. Am. Birding Assoc., Colorado Springs. Accepted 1 0 February 1 995 106 NOTES HOUSE WRENS FEEDING FISH TO THEIR NESTLINGS TARA Y. WILLIAMS, Department of Zoology, Brigham Young University, Provo, Utah 84602 (current address: Canyonlands National Park, Moab, Utah 84532) DAVID S. PENNOCK, Department of Zoology, Brigham Young University, Provo, Utah 84602 (current address: Department of Systematics and Ecology, University of Kansas, Lawrence, Kansas 66045-2106) The House Wren ( Troglodytes aedon) is a primarily insectivorous passerine that gleans most of its food from shrubs or trees (Kendeigh 1941 , Guinan and Sealy 1987, 1989). Although the Winter (Troglodytes troglodytes) and Carolina ( Thryothorus ludovicianus ) Wrens have been reported to feed on vertebrates occasionally (Haslam 1844, Bent 1948, Huxley 1949, Bagnall-Oakley 1968), we found no reports in the literature of House Wrens feeding on vertebrates. We report here House Wrens feeding fish to their nestlings. We established a grid of 50 nestboxes, placed at 50-m intervals, at Daniels Pass, 24 km east of Heber, Utah. The plot is located on an east-facing slope in a forest of Quaking Aspen (Populus tremuloides ) with White Fir (Abies concolor ). The under- story is dominated by Mountain Snowberry (Symphoricarpos oreophilus). There is a seep north of the plot, and an intermittent stream runs to the southwest of it. During the breeding seasons of 1987, 1988, and 1989, we monitored the nestboxes, used mainly by House Wrens and Tree Swallows ( Tachycineta bicolor). The boxes were built to facilitate the attachment of a small video camera that could film the inside of the box. The camera hole was blocked with a cork when the camera was not attached. Before filming, we placed a plexiglass lid on top of the box to allow light into the box. After the camera was attached, we waited 10 to 15 minutes before beginning filming to allow the birds to adjust to the intrusion on their environment. During the three-year study period, 51 House Wren nests were monitored. We filmed each nest at least once while it contained nestlings during all years. Seventy- three videotapes, averaging 1.8 hours in length, were made. Adult birds were mist- netted and banded with U.S. Fish and Wildlife Service bands and color bands so that we could identify individuals in the field. See Pennock (1990) for further details on the study site and methods. During our study, we observed adult House Wrens feeding small fish to their nestlings on five occasions. One case each was recorded, in 1987 and 1988. Three cases at the same nest were recorded in 1989. The fish were whole and in some cases moving, so they probably were not scavenged. In each case, the fish were fed whole to the nestlings. The lengths of the fish, as measured from the videotapes by means of an image-analysis program on an IBM AT microcomputer, were 3.14, 2.76, 2.36, 1.27, and 0.89 cm. As evidenced by the videos, the House Wrens fed their young primarily with larval and adult Lepidoptera. Coleopteran and hymenopteran prey were also identified (Pennock 1990). House Wrens frequently nest near water (Kendeigh 1941). The three pairs that fed fish to their nestlings all had water within their territory, at distances of 20 to 50 meters from the nest. Twenty, or 39%, of the nests monitored were located within 50 meters of a water source. Although five incidents in nearly 150 hours of videotape, showing about 20 feeding bouts per hour, are not very many, fish may be regular in the diet of some House Wrens. The behavior, shown by different individual birds each year, was recorded in all three years of the study. In both 1987 and 1988, only one film was made of each nestbox. If this behavior was extremely rare, the probability of its being recorded in a two-hour sample of a two-week nestling period would be very low. In 1989, the Western Birds 26:107-108, 1995 107 NOTES nestbox in which the parents fed fish to the nestlings was videotaped twice during the nestling period. Fish were fed to the nestlings during both taping sessions, and the activity was recorded twice during one of the sessions. These observations suggest the House Wren to be more plastic in its diet selection than may have previously been thought. Funding during this project was provided by the Brigharn Young University Zoology Department. Dr. Brian A. Maurer established the study plot and provided equipment for field work. Dr. Dennis K. Shiozawa provided equipment for analysis of the video tapes in his laboratory. Richard Jensen assisted in a comprehensive literature search. LITERATURE CITED Bagnall-Oakley, R. P. 1968. Wrens feeding on small fish. Br. Birds 61:313-314. Bent, A. C. 1948. Life histories of North American nuthatches, wrens, thrashers and their allies. U.S. Natl. Mus. Bull. 195. Guinan, D. M., and Sealy, S. G. 1987. Diet of House Wrens ( Troglodytes aedon) and the abundance of the invertebrate prey in the dune-ridge forest, Delta Marsh, Manitoba. Can. J. Zool. 65:1587-1596. Guinan, D. M., and Sealy, S. G. 1989. Foraging-substrate use by House Wrens nesting in natural cavities in a riparian habitat. Can. J. Zool. 67:61-67. Haslam, S. H. 1844. Anecdote of the Common Wren. Zoologist {1} 2:564. Huxley, J. S. 1949. Wren feeding young on fish. Br. Birds 42:185-186. Kendeigh, S. C. 1941. Territorial and mating behavior of the House Wren. 111. Biol. Monogr. Univ. of 111. Press, Urbana. Pennock, D. S. 1990. Seasonal distribution of hatching asynchrony and brood reduction in House Wrens. M.S. thesis, Brigham Young Univ., Provo, UT. Accepted 9 March 1 995 108 COMMENTARY TIM MANOLIS, 808 El Encino Way, Sacramento, California 95864 Following up on the essay by Patten et al. [W. Birds 26:54-64), I would like to illuminate some of their comments from a local perspective. There are a number of things that local groups (e. g., the Sacramento Audubon Society) can do on a small scale (e. g., Sacramento County and the greater Sacramento area) to improve our knowledge of the distribution of California’s birds. Sacramento Audubon maintains a file of observations, volunteered by members, that dates back to the early 1950s. We welcome written reports (submission encouraged on a monthly basis) of any observa- tions members feel are noteworthy, as well as reports of the more unusual birds on a bird-report phone line. Since 1986, reported observations have been entered in a computer data base, and, over time, we hope to enter all pre-1986 records into this data base as well. Data for two local Christmas Bird Counts (Sacramento and Folsom) are also maintained in computer files. Sacramento Audubon has a records committee modeled on the California Bird Records Committee (CBRC) that compiles and reviews local reports of species of rare or unseasonal species not reviewed by the CBRC. Finally, Sacramento Audubon volunteers recently completed collecting data for a Sacramento County breeding-bird atlas, the results of which are in preparation. The level of effort is not up to that of some California counties, but it is probably better than most, if only because there is a relatively high density of observers in the Sacramento area. Now, at the risk of sounding as if I am crying in my birdseed, I’d like to discuss some of the problems faced in implementing this system. First, very few people report observations on a regular basis, and because the majority of these report only rarities and find the phone line more convenient, only two or three submit written reports on a monthly basis. The use of bird “hot lines” in recent years has also exacerbated another problem — the tendency of people to bird in mobs, visit the same old birder-worn locales, and call up the tape when planning a day afield, rather than to go out exploring new places on their own. Finally, there is a tendency for those who become adept at identifying birds to grow restless with the local scene and start traveling further and further in search of new birds. Thus many of the local birders best qualified to assist on the Sacramento County breeding-bird atlas were too busy chasing rarities and visiting other countries to be of much use, and few have shown any interest in doing library research or data analysis in order to speed publication of the results. But even if the system for data collection and analysis for Sacramento County, rudimentary as it is, were to flourish beyond our wildest expectations, it would still be operating to a great extent in isolation, rather than in an integrated statewide network of such local systems. At present, the data collected in computer files, summarized and edited four times a year and submitted, as a printout, to the regional editors for National Audubon Society Field Notes, is copied by hand into the regional “books.” The overworked and unpaid regional editors are months behind in this task, and faced with tight restrictions on the lengths of their published summaries are often limited to discussing only the rarities in print. Is the situation hopeless? I don’t think so, but agree with Patten et al. that progress won’t come easily. WFO sponsors the CBRC and occasionally other efforts to integrate field ornithology statewide (e. g., a series of county 1 bird-atlas workshops at recent WFO meetings). Whether under the WFO banner or another banner yet to be unfurled, the challenge to us all is to expand this effort greatly and develop a useful system to compile, analyze, and integrate fine-scale data on the distribution and status of California birds. Western Birds 26:109, 1995 109 PRESIDENT’S MESSAGE The nineteenth annual meeting of the Western Field Ornithologists was held jointly with the Morro Coast Audubon Society in Morro Bay, California, 30 September through 2 October 1994. The meeting was a great success, from both a birding standpoint and by virtue of the excellent information presented during the Saturday paper session. In addition, Dr. Arnold Small provided an superb banquet presentation on faunal comparisons between the North and South poles. The birding highlights are too numerous to list, but a Streaked Shearwater ( Calonectris leucomelas ) observed during the pelagic trips illustrates a morsel. The Morro Coast Audubon Society organized all accommodations and produced an outstanding meeting plus activities. WFO is very thankful to the many volunteers who helped in the organization, field trips, and logistics for this meeting. One person who deserves special credit is Jim Royer. The twentieth annual meeting will be held from 16 to 18 June 1995 in Spokane, Washington, jointly with the Washington Ornithological Society. Field trips will be conducted each day of the meeting, with special trips to Salmo Mountain, the high mountains of the Idaho panhandle, and the Palouse. On Saturday there will be an all- day paper session, followed by our usual banquet. The meeting will be at an ideal time for birding in the Columbia Basin and Palouse of Washington and Idaho. This is WFO’s first meeting in eastern Washington, so we are hoping for an outstanding turnout. Please plan to attend. Robert McKernan WFO President 110 Wing Your Way to. . . Western Field Ornithologists 20th Annual Meeting with the Washington Ornithological Society SPOKANE, WASHINGTON 16-18 June 1995 at the Spokane Holiday Inn- West Field trip destinations include Salmo Mountain, the Idaho panhandle, the Palouse of Whitman County, Mount Spokane, Turnbull National Wildlife Refuge, and Riverside State Park. Space in a bus can be reserved for some trips. Likely species include the Spruce and Ruffed Grouse, Three-toed and Black-backed Woodpeckers, Boreal Chickadee, American Redstart, Northern Waterthrush, Grasshopper Sparrow, and Bobolink. Talks, buffets, banquets, and the notorious identification panel round out the meeting. For more information contact Russell Rogers, 4510 Glenn Way SW, Seattle, WA 98116. in CORRIGENDUM The statement in the final line of the summary in Erickson et al., First Record of the Marbled Murrelet and Third Record of the Ancient Murrelet for Mexico (W. Birds 26:39-45, 1995), concerning the southernmost locality for the Ancient Murrelet, is incorrect. Although the species is not known farther south than Ensenada on the Pacific coast of North America, a record for Lake Pontchartrain, Louisiana, and seven for Hong Kong { Hong Kong Bird Report 1993:51-52) are farther south. We regret any confusion this may have caused. Richard A. Erickson and Michael A. Patten □ Excellent papers on identification, distribution, occurrence, movements and behaviour of Palearctic birds □ Regular contributions on Asian-Pacific birds □ Latest news on rare and interesting birds in the Netherlands and the Western Palearctic □ Well produced with numerous high quality colour photographs □ Yearly report on rare birds in the Netherlands □ In English or with extensive English summaries For information or a free sample issue, write to: Dutch Birding, Postbus 7561 1 . 1070 AP Amsterdam, Netherlands Subscribers to Dutch Bitdinft can claim 25 % oif.i British Birds subscription 112 WESTERN BIRDS Quarterly Journal of Western Field Ornithologists President: Robert McKeman, 1230 Friar Lane, Redlands, CA 92373 Vice-President: Steve Summers, P.O. Box 202, Silver Lake, OR 9763 8 Treasurer/Membership Secretary: Dorothy Myers, 6011 Saddletree Lane, Yorba Linda, CA 92686 Recording Secretary: Jean-Marie Spoelman, 4629 Diaz Drive, Fremont, CA 94536 Circulation Manager: Mamie S. Crook, P.O. Box 10483, San Bernardino, CA 92423 Directors: Bruce Deuel, Kimball Garrett, Peter Gent, Guy McCaskie, Robert McKeman, Steve Summers, Bill Tweit, Janet Witzeman, David Yee Editor: Philip Unitt, 3411 Felton Street, San Diego, CA 92104 Associate Editors: Cameron Barrows, Tim Manolis, Thomas W. Keeney Graphics Manager: Virginia P. Johnson, 4637 Del Mar Ave., San Diego, CA 92107 Photo Editor: Peter La Tourrette, 1019 Loma Prieta Ct., Los Altos, CA 94024 Secretary , California Bird Records Committee: Michael A. Patten, P. 0. Box 51959, Riverside, CA 92517-2959 Editorial Board: Robert Andrews, Alan Baldridge, Andrew J. Berger, Laurence C. Binford, R. Wayne Campbell, David F. DeSante, Jon L. Dunn, Richard Erickson, William T. Everett, Kimball L. Garrett, Joseph R. Jehl, Jr., Ned K. Johnson, Virginia P. Johnson, Brina Kessel, Stephen A. Laymon, Paul Lehman, John S. Luther, Guy McCaskie, Joseph Morian, Harry B. Nehk, Dennis R. Paulson, Gary H. Rosenberg, Oliver K. Scott, Ella Sorensen, Richard W. Stallcup, Charles Trost, Terence R. Wahl, Bruce Webb Membership dues, for individuals and institutions, including subscription to Western Birds: Patron, $1000; Life, $350; Supporting, $50 annually; Contributing, $30 annually; Family, $22; Regular, U.S., $18 for one year, $35 for two years, $50 for three years; outside U.S., $23 for one year, $45 for two years, $65 for three years. Dues and contributions are tax-deductible to the extent allowed by law. Send membership dues, changes of address, correspondence regarding missing issues, and orders for back issues and special publications to the Treasurer. Make checks payable to Western Field Ornithologists. Back issues of California Birds/Westem Birds: $20 per volume, $5.00 for single issues. Xerox copies of out of print issues (Vol. 1, No. 1; Vol. 2, Nos. 1 and 4; Vol. 6, No. 2): $5.50 each. Ten-column Field List of California Birds: $1.00 each, 10 to 39 $0.80 each, 40 or more $0.70 each. Checklist of the Birds of California: $2.00 each, 10 or more $1.50 each. Pelagic Birds of Monterey Bay, California: $2.50 each, lOormore $2.00 each, 40 or more $1.50 each. All postpaid. Published April 15, 1995 ISSN 0045-3897 Vol. 26, No. 3, 1995 Volume 26, Number 3, 1995 Seventeenth Report of the California Bird Records Committee: 1991 Records Michael A. Patten , Shawneen E. Finnegan , and Paul E. Lehman 113 Noteworthy Records of Birds in Northwestern Baja California, Mexico Philip Unitt, Amadeo M. Rea, Eduardo Palacios, Eric Mellink , Lucia Alfaro, and Salvador Gonzalez 144 NOTES More Records of Breeding Barn Swallows in Riverside, California Cm-Tj } A. Lee 155 Probable Breeding Population of the Black Rail in Yuba County, California Paul A. Aigner , Jerry Tecklin, and Catherine E. Koehler 157 Semipalmated Plover Nesting on the Oregon Coast Carole E, Hallett, Bruce R. Casler, and Mark A, Stern 161 First Confirmed Breeding of the Least Bittern in Inyo County, California Andrew Kirk 165 Hudsonian Godwit Migration at Carter Spit, Alaska Bruce E. Seppi 167 Bulletin Board 168 Corrigendum 168 Cover photo by © Frans Lanting of Santa Cruz, California: Black- footed Albatross (Diomedea nigripes ), Midway Island, Northwestern Hawaiian Islands, July, 1994. This juvenile is about to fledge— “a brand new blackfoot.” Western Birds solicits papers that are both useful to and understandable by amateur field ornithologists and also contribute significantly to scientific literature. The journal welcomes contributions from both professionals and amateurs. Appropriate topics include distribution, migration, status, identification, geographic variation, conservation, behavior, ecology, popula- tion dynamics, habitat requirements, the effects of pollution, and techniques for censusing, sound recording, and photographing birds in the field. Papers of general interest will be considered regardless of their geographic origin, but particularly desired are reports of studies done in or bearing on the Rocky Mountain and Pacific states and provinces, including Alaska and Hawaii, western Texas, northwestern Mexico, and the northeastern Pacific Ocean. Send manuscripts to Philip Unitt, 3411 Felton Street, San Diego, CA 92104. For matter of style consult the Suggestions to Contributors to Western Birds (8 pages available at no cost from the editor) and the Council of Biology Editors Style Manual (available for $24 from the Council of Biology Editors, Inc., 9650 Rockville Pike, Bethesda, MD 20814). Reprints can be ordered at author’s expense from the Editor when proof is returned or earlier. Good photographs of rare and unusual birds, unaccompanied by an article but with caption including species, date, locality and other pertinent information, are wanted for publication in Western Birds. Submit photos and captions to Photo Editor. Also needed are black and white pen and ink drawings of western birds. Please send these, with captions, to Graphics Manager. WESTERN BIRDS Volume 26, Number 3, 1995 SEVENTEENTH REPORT OF THE CALIFORNIA BIRD RECORDS COMMITTEE: 1991 RECORDS MICHAEL A. PATTEN, P. O. Box 51959, Riverside, California 92517-2959 SHAWNEEN E. FINNEGAN and PAUL E. LEHMAN, P, O. Box 379, Cape May, New Jersey 08204-0379 A concise overview of the California Bird Records Committee (hereafter “CBRC” or “the Committee”) has not been published in many years, save for a brief sketch by Patten (1991). Therefore, this report begins with a bit of history and background, if only to inform the newest generation of field ornithologists who may not be entirely familiar with the Committee s functions and goals. Following concerted effort by C. J. Ralph and others, the CBRC was established in 1970, the first records committee in North America. Origi- nally it was called the “Rare Bird Committee” of the California Field Ornithologists, and its initial intent, as stated by Alan M. Craig (1970), was to “ascertain which of the multitudinous observations fmade in California] are acceptable beyond any reasonable doubt.” Some 4000 records later, this goal still stands, but rather than limiting itself to the review of sight records, the CBRC now reviews all records of vagrant birds reported in California, be they sight, sound, photographic, or specimen records. In general, records are reviewed only for species that average four or fewer occurrences per year in California and have been recorded fewer than 100 times. The Committee solicits information on all reports of species on its Review List, and any species potentially new to California, and encourages observers to support the Committee’s review process by submitting written reports, photographs, tape recordings, and other documentation to the CBRC’s secretary. With the exception of the Kentucky Warbler ( Oporornis formosus), post- 1994 records of which are no longer reviewed by the CBRC, the current Review List remains unchanged since the 16th report (Heindel and Garrett 1995). Copies of the Review List, the current state list, and the CBRC’s by-laws are available from the secretary, Patten, at the address above. Western Birds 26:113-143, 1995 113 CALIFORNIA BIRD RECORDS The CBRC consists of ten voting members, one of whom acts as secretary. The secretary is responsible for cataloging all the documentation received, for ensuring that each record is circulated through the Committee, and for compiling the final record once it has completed circulation. Records are circulated by mail to all members of the Committee, each of whom reviews documentation constituting a given record. Each member is responsible for assessing whether or not the information provided is sufficient to support the identification of the reported species. For this reason, it is important for observers to include as many details as possible, no matter how trivial they may seem. The majority of records not accepted by the CBRC receive this verdict because documentation was not thorough enough to support the identification, not because the identification was necessarily incorrect. In some instances the more tenuous question of natural occurrence is the issue. In these instances each member reviews available information and judges whether a bird has more likely arrived under its own power or with deliberate aid from humans. Records span the continuum bounded by these scenarios, and individual philosophy of Com- mittee members plays a substantial role in the decision-making process. Records for which information is insufficient to the extent that natural occurrence is uncertain may be placed on the Supplemental List. See Heindel and Garrett (1995) for a discussion of the natural-occurrence issue. All information reviewed by the CBRC, including written documentation, photographs, videotapes, voice recordings, and comments of its members, is placed in a permanent archive at the Western Foundation of Vertebrate Zoology (439 Calle San Pablo, Camarillo, California 93012-8506). In this way the CBRC serves a valuable function to researchers, many of whom would otherwise presumably have a difficult time tracking down information about particular reports of vagrant birds. Records at the Western Founda- tion are catalogued by record number and are available to anyone interested in receiving information beyond what is published in the Committee’s regular reports. Other important functions of the CBRC are to maintain a checklist of California birds and to publish regular reports, such as this one, listing recent decisions. With regard to the state list, the first accepted records for California of the Arctic Loon ( Gauia arctica ), Alder Flycatcher ( Empidonax a l norum), and Little Bunting (Emberiza pusilla ) are included in this report. In addition, historical firsts (predating all other currently accepted records) for the Blue Jay ( Cyanocitta cristata) and Gray Catbird ( Dumetella carolinensis ) are included. This report also covers prospective first records of Townsend’s Shearwater ( Puffinus auricularis), Canyon Towhee (Pipilo fuscus), and McKay’s Bunting ( Plectrophenax hyperboreus), none of which was considered acceptable by the Committee. With the additions listed above, and with recently accepted records of the Great Frigatebird ( Fregata minor ) and Fork-tailed Flycatcher ( Tyrannus sauana), both of which will be treated in the 18th CBRC report, the California state list currently stands at 586. Format, This report contains records extending from December 1916 to June 1992, although the vast majority of the records are from 1991. Of the 232 records included, the Committee accepted 75.4%, a rate consistent 114 CALIFORNIA BIRD RECORDS with the most recent two reports (Patten and Erickson 1994, Heindel and Garrett 1995). As is typical, the majority of accepted records were from coastal areas (±70%), with 15% of the coastal records from Southeast Farallon Island. The format of CBRC reports is now standard. Species are listed in the same order as in the most recent American Ornithologists’ Union Check- list (A.O.U. 1983) and supplements. Species names are followed, in parentheses, by the number of accepted records for California through the period covered by this report. Records are listed chronologically by first date of occurrence, except when an alternate arrangement allows for a clearer presentation. Each record includes the locality (including a standard abbre- viation for the county; see below), a full date span (in general following that listed in American Birds or other published source), a list of observers who submitted documentation, and the CBRC record number. If the Committee has evidence that a published date span is incorrect, the CBRC-accepted date(s) are listed in italics. Observers are listed alphabetically (by surname), except those who found and/or identified the bird; these observers are listed first, followed by a semicolon. Birds returning for subsequent winters or after other lengthy absences are reviewed under separate record numbers, and the Committee judges (by simple majority) whether the subsequent record(s) involve(s) the same bird(s). The Committee does not decide issues of subspecies, sex, or age, although members often express their views on these issues in comments. Annotations in this report regarding subspecies, sex, and age are ours, although many are based upon the collective opinions of the Committee. Abbreviations and Symbols. The Committee uses standard abbrevia- tions for counties. Those appearing in this report are ALA, Alameda; BUT, Butte; CC, Contra Costa; COL, Colusa; DN, Del Norte; HUM, Humboldt; IMP, Imperial; INY, Inyo; KER, Kern; LA, Los Angeles; MNO, Mono; MOD, Modoc; MRN, Marin; MTY, Monterey; ORA, Orange; RIV, River- side; SBA, Santa Barbara; SBE, San Bernardino; SBT, San Benito; SCL, Santa Clara; SCZ, Santa Cruz; SD, San Diego; SF, San Francisco; SIS, Siskiyou; SJ, San Joaquin; SLO, San Luis Obispo; SM, San Mateo; SON, Sonoma; VEN, Ventura. Abbreviations for museums cited in this report are CAS, California Academy of Sciences, San Francisco; CSUC, California State University, Chico; HSU, Humboldt State University, Areata; LACM, Natural History Museum of Los Angeles County, Los Angeles; SBCM, San Bernardino County Museum, Redlands; SDNHM, San Diego Natural History Museum, San Diego. Other abbreviations are AFB, air force base; Co., county; I., island; L., lake; mi., miles; mtn., mountain; nmi., nautical miles; NM, national monument; NP, national park; NS, national seashore; NWC, naval weapons center; NWR, national wildlife refuge; pt., point; SB, state beach; SP, state park. Symbols used in this report are as follows: an asterisk (*) preceding a species name indicates that species is no longer on the CBRC Review List. Symbols following an observer’s initials signify that the observer submitted a photograph (t), a videotape (-?), or a voice recording (§). These symbols are 115 CALIFORNIA BIRD RECORDS used only if the documentation submitted supported the identification of the bird(s) in question. See Patten and Erickson (1994) for a more complete explanation of abbreviations and symbols used in CBRC reports. RECORDS ACCEPTED ARCTIC LOON Gavia arctica (2). One at Abbott’s Lagoon, Pt. Reyes NS, MRN, 2-17 Nov 1991 (SNGH, DLR; SFB. JLD, GHF, FG, HG, BHt, CHK, THK, LLf, MJL, GMcC, JM, MAP, MMR, DRt, RS, MMTf, SBT, JTf, BY; 182-1991) was the first of its species to be found in California. On the heels of this bird was one at Morro Bay, SLO, 7-23 Dec 1991 (Figure 1; TME; SEFt, KAH, JTH, PEL: 83-1992). These records were the first of confirmed Arctic Loons in North America outside of Alaska, although there is a tentative sight report from Massachusetts (Evered 1985) and another recent report from that state ( Bird Observer 22:206); two British Columbia specimens alleged to be this species proved to be Pacific Loons (G. pacifica; Campbell et al. 1990). Reinking and Howell (1993) published a full account of the Pt. Reyes bird, with additional taxonomic and identification information on distinguishing the Arctic from the Pacific Loon. An excellent videotape of the first bird, and photographs of both, helped the Committee in its identification assessment of this difficult, recently split (A.O.U. 1985) species pair. See also Walsh (1988), Roberson (1989), and Schulenberg (1989) regarding the field identification of basic- plumaged Arctic Loons; notes by McCaskie et al. (1990) and Dunn and Rose (1992) cover alternate-plumaged birds. Figure 1. First-winter Arctic Loon (83-1992) at Morro Bay, San Luis Obispo Co., 8 December 1991. 116 Photo by Shawneen E. Finnegan CALIFORNIA BIRD RECORDS MOTTLED PETREL Pterodroma inexpectata (52). Seventeen were between 37°10.45' N, 124°07.35’ W and 37°00.67’ N. 124°27.84' W, 66-90 nmi. SW of Pt. Reyes, MRN, 16 Nov 1991 (SFBf, JLD, JM, MMTt, SBTt; 186-1991). Photographs of two of these birds appeared in Am. Birds 46:143 and 46:169. Three were 80-84 nmi. SW of Pt. Reyes, MRN, 14 Dec 1991 (SFB, JMDf, RAE; 234-1991) as follows: 36°58.95' N, 124°03.86' W, 79.8 nmi. SW of Pt. Reyes; 36°57.63' N, 124°07.06' W, 82.6 nmi. SW of Pt. Reyes; and 36°56.74’ N, 124°07.79' W, 83.6 nmi. SW of Pt. Reyes. STEJNEGER’S PETREL Pterodroma longirostris (4). One was at 32°35.85' N, 122°46.36' W, about 152 nmi. SW of San Miguel L, SBA, 14 Nov 1990 (JLD; 103- 1991). All four Stejneger’s Petrel records accepted by the CBRC fall in the narrow window of 14 to 17 November. See Luther et al. (1983), DeBenedictis (1991), Kaufman (1991), McCaskie and Roberson (1992), and Heindel and Garrett (1995) for information about previous records for California waters. BROWN BOOBY Sula leucogaster (38). An adult was 1 mile north of Santa Barbara L, SBA, 8 Aug 1991 (PP; 17-1992), and an adult considered to be the same bird was at the east side of Santa Barbara I., SBA, 2 Jun 1992 (DU; 233-1992). An immature was 2 miles west of the entrance to San Diego Bay, SD, 14 Dec 1991 (DP; 124-1992). Roughly one-fourth of California records are from the coast, where their occurrence appears more random than the marked invasions into the interior (mainly the Salton Sea). RED-FOOTED BOOBY Su/a sula (9). An immature female found ill at Redondo Beach, LA, 18 Aug 1991 was moved by animal control officials to King Harbor, LA, where it was documented (JAJ, DLMf; 33-1992). The bird was recaptured, but died in a rehabilitation center; unfortunately, the specimen was not saved. REDDISH EGRET Egretta rufescens (58). An immature was in the Tijuana R. Valley and estuary, SD, 22 Nov-15 Dec 1990 (GMcC; 4-1991); unfortunately, additional documentation from two observers (JO and RLR) was lost in the mail. An adult with a deformed bill returned for its tenth winter to the south end of San Diego Bay, SD, 13 Oct 1991-10 Jan 1992 (GMcC; 169-1991). An immature was at Del Mar, SD, 16-19 Oct 1991 (JO; RAE; 192-1991), and another immature was at the south end of San Diego Bay, SD, 11 Nov 1991-29 Mar 1992 (GMcC; CAM, SBTt; 1-1992). This distribution of records in this report is typical of the species in California: the Reddish Egret is a rare but regular fall and winter visitor to southwest- ern San Diego Co., but extremely rare elsewhere in the state. YELLOW-CROWNED NIGHT-HERON Ngctanassa violacea (16). Two were together in the Tijuana R. Valley, SD, 13 Oct 1991-25 Jan 1992, with one remaining through 31 Mar 1992 (GMcC; RCa, JLD, DR; 170-1991, 171-1991). One (170-1991) was treated as having returned for its second winter (same as 153- 1990; Heindel and Garrett 1995), whereas the other (171-1991), a subadult that molted into adult plumage, had been present since 16 Jun 1991 (same as 88-1991; Heindel and Garrett 1995). An adult remained along the Los Angeles R., Glendale, LA, 13 Sep-30 Nov 1991 (KLG; JLD, MHf, SJ; 219-1991), the third acceptable county record. This species is scarcer in California than the other “southern herons,” the Reddish Egret, Tricolored Heron (Egretta tricolor ), and Little Blue Heron (E. caerulea). GARGANEY Anas querquedula (14). Males in alternate plumage were at Wood- land, YOL, 19 Jun 1988 (MCt, GE; 131-1988) and in Watsonville, SCZ, 2 Apr 1991 (KK; 61-1992). A female or immature male was at Arroyo Laguna, SLO, 2-13 Oct 1991 (TMEt; GPSf; 230-1991). The male at Woodland stimulated a lively debate regarding its natural occurrence, as it was nearly two months later than any previous spring record for California. The 117 CALIFORNIA BIRD RECORDS date span for prior spring records is 10 March (1985; a male photographed at Modoc NWR, MOD; Dunn 1988) to 30 April (1990; a male present since 27 March 1990 at Bolinas, MRN; Patten and Erickson 1994). Though records are few, their peak appears to be late March. Given the several June records for British Columbia and Alberta (Spear et al. 1988), the species’ supposed rarity in captivity in North America (Todd 1979, but cf. Knapton 1994), and its breeding or summering in the Old World as far south as the Iberian Peninsula (Cramp and Simmons 1977), the majority of the Committee felt that this bird was more likely of natural occurrence. ‘TUFTED DUCK Aythya fuligula (70). A female at Mare L, Vallejo, SOL, 2 Feb 1991 (DA; 27-1991) was considered to be the same as one at L. Dalwigh, SOL, 21 Mar 1991 (MBG; 74-1991), An adult male returned for its fourth winter to the San Francisco, SF, and Rodeo Lagoon, MRN, area from 23 Oct 1991 to 7 Mar 1992 (SFB, LL, JM, MMR, DSt, RS, SBT; 216-1991). This bird moved among L. Merced, SF, Rodeo Lagoon, and several lakes in Golden Gate Park, SF, during its stay. Previous occurrences of this bird were 19 Nov 1988-27 Mar 1989 (257-1988), 9 Jan-26 Apr 1990 (7-1990/45-1990), 18 Jan-3 Mar 1991 (48-1991), and 29 Dec 1990 (56-1991). An adult male at L. Isabella, KER, 17-19 Jan 1992 (GH; MOC, JLD, MTH, GMcC, MAP; 52-1992) was Kern County’s second; Am. Birds 46:315 erroneously listed the date span as 17-18 Jan 1992. A male returned to Quail L., LA, 1 Feb^S Mar 1991 (KLG; 103-1992) and 11-17 Nov 1991 (KLG; 19-1992); see Roberson (1993) for a summary of previous dates for this bird, which was in eclipse plumage in November 1991. The second for San Diego Co., and the first widely observed, was a male at Miramar Reservoir, SD, 13 Jan-9 Feb 1992 (PAG; TC, JLD, SEF, PEL, GMcC, MAP; 19-1992). Riverside County’s third record was of an adult male in San Timoteo Canyon, RIV, 27 Feb-15 Mar 1992 (GMcC, MAPf; 71-1992). As the Tufted Duck has proved to be a regular part of California’s winter avifauna, albeit a very rare one, the Committee has ceased reviewing records after the winter of 1991/1992. Roughly 80% of the records are from the coastal slope of California from Los Angeles Co. northward. KING EIDER Somateria spectabilis (31). A female was seen in flight at Pt. Reyes NS (Drakes Beach), MRN, 18 Oct 1991 (JM; 215-1991). An immature male at Seal Beach Pier, ORA, 13-31 Dec 1991 later moved one-half mile north to Belmont Shores, LA, where it stayed 7-19 Jan 1992 (CTC, BED, JRGt, KLG, GMcC, CAM, MAPI; 213-1991). A photograph of the Seal Beach bird appeared in Am. Birds 46:315. STELLER’S EIDER Polysticta steileri (3). California’s third was at Bodega Bay, SON, 27 Oct 1991-2 May 1992 (Figure 2; SBTf; JA, SFB, SC, JLD, GHF, SEFt, EDGt, FG, HG, MBG, KHa, LL, MJLf, EM, JM, TM, GMcC, SWM, DWNf, MAPf, DR, MMR, RS; 181-1991); a photograph was published in Am. Birds 46:144. Despite initial confusion about this bird’s age and sex (most observers commenting on this issue initially felt that it was a first-winter male), its plumage changed only in becoming browner during its stay. Thus, it appears to have been a female, perhaps even an adult. ZONE-TAILED FIAWK Buteo albonotatus (32). An adult was in San Diego, SD, 20-21 Dec 1916 (Grey 1917); it was collected on the latter date and is now an uncatalogued life mount (#SDNHM; 55-1993). This record was only the third for California. An adult at L. San Marcos, SD, 21-24 Dec 1991 (JOZ; 180-1992) was considered a returning bird (same as 107-1991; Heindel and Garrett 1995). HUDSONIAN GODWIT Limosa haemastica (11). A juvenile was at Crescent City, DN, 29 Aug 1991 (ADB; GSL, BSif; 132-1991); a photograph of it appeared in Am. Birds 46:145. Another juvenile first seen in flight at Areata Bottoms, HUM, 118 CALIFORNIA BIRD RECORDS 6 Sep 1991, subsequently settled in at Mad R. Co. Park, HUM, 9-20 Sep 1991