'■', ' U'i; I',: OMJFORNIAI FISH-GAME "CONSERVATION OF WILDLIFE THROUGH EDUCATION" [ VOLUME 71 APRIL 1985 NUMBER 2^1 V 7^ — iPiSHl \i (x^^Swjr* ^^^ ^'^^'[J^^^ I ^*e» ^"S^wft-^ ^^F 1 ^w*''^- ^^B^^\ La J ^t^ |%#' »'^y California Fish and Game is a journal devoted to the conservation of wild- life. If its contents are reproduced elsewhere, the authors and the California Department of Fish and Game would appreciate being acknowledged. Subscriptions may be obtained at the rate of $5 per year by placing an order with the California Department of Fish and Game, 1416 Ninth Street, Sacramento, California 95814. Money orders and checks should be made out to California Department of Fish and Game, Inquiries regarding paid sub- scriptions should be directed to the Editor. Complimentary subscriptions are granted, on a limited basis, to libraries, scientific and educational institutions, conservation agencies, and on exchange. Complimentary subscriptions must be renewed annually by returning the post- card enclosed with each October issue. Please direct correspondence to: Perry L. Herrgesell, Ph.D., Editor California Fish and Game 1416 Ninth Street Sacramento, California 95814 u 0 V VOLUME 71 APRIL 1985 NUMBER 2 Published Quarterly by STATE OF CALIFORNIA ■ THE RESOURCES AGENCY DEPARTMENT OF FISH AND GAME —LDA— STATE OF CALIFORNIA GEORGE DEUKMEJIAN, Governor THE RESOURCES AGENCY GORDON VAN VLECK, Secretary for Resources FISH AND GAME COMMISSION WILLIAM A. BURKE, Ed.D., President Brentwood BRIAN J. KAHN, Vice President ABEL C. GALLETTI, Member Santa Rosa Los Angeles ALBERT C. TAUCHER, Member Long Beach DEPARTMENT OF FISH AND GAME JACK C. PARNELL, Director 1416 9th Street Sacramento 95814 CALIFORNIA FISH AND GAME Editorial Staff Editorial staff for this issue consisted of the following; Wildlife William E. Grenfell, Jr. Marine Resources Robert N. Lea, Ph.D. Anadromous Fisheries Kenneth A. Hashagen, Jr. Inland Fisheries Ron Pelzman, Jack Hanson Editor-in-Chief Perry L. Herrgesell, Ph.D. CONTENTS Page Breeding Range and Population Studies of Common Snipe in California Laurence A. McKibben and Paul Hofmann 68 Growth, Food and Habitat of Age 0 Smallmouth Bass in Clair Engle Reservoir, California Daniel Okoth Okeyo and Thomas J. Hassler 76 Life History of the Sacramento Sucker, Catostomus occiden- talism in Thomes Creek, Tehama County, California Nick A. Villa 88 Notes Growth of Grass Carp, Ctenopharyngodon idella, in Artificial Central Arizona Ponds Paul C. Marsh and Mark A. Dhaenens 107 Orientation of Juvenile Chinook Salmon, Oncorhynchus tsha- wytscha, and Bluegill, Lepomis macrochirus, to Low Water Velocities Under High and Low Light Levels Charles H. Hanson and Erik Jacobson 110 Radio-Tagged Harbor Seal, Phoca vitulina richardsi, Eaten by White Shark, Carcharodon carcharias, in the Southern Cali- fornia Bight Brent S. Stewart and Pamela K. Yochem 113 Additional Records of Pronotogrammus multifasciatus and Gempylus serpens From California Lawrence L. C. Jones, Robert R. Johnson and Judith Hopkins 116 Pugheadedness in the California Roach, Hesperoleucus sym- metricus (Baird and Girard) Robert A. Leidy 117 Milkfish, Chanos chanos (Forsskal, 1775), Taken in Southern California Adds New Family (Chanidae) To The California Marine Fauna John M. Duffy and Hannah J. Bernard 122 Experimental Lead Dosing of Northern Pintails in California Bruce Deuel 125 68 CALIFORNIA FISH AND GAME Calif. Fish and Came 71 (2): 68-75 1985 BREEDING RANGE AND POPULATION STUDIES OF COMMON SNIPE IN CALIFORNIA ' LAURENCE A. McKIBBEN California Department of Fish and Game 468 Justeson Road Gridley, CA 95948 AND PAUL HOFMANN' Humboldt State University Areata, CA 95521 Studies were conducted between 1978 and 1981 to determine the breeding range of Common Snipe, Gallinago gallinago delicata, in California. Methods of measuring population densities and monitoring population trends were also investigated. We estimate that approximately 38,000 ha of potential breeding habitat exists within the known breeding range in the state. Breeding grounds are used from late March through September. The peak of breeding and nesting activity occurs in May and June. Banding information indicates that snipe tend to return to the same breeding grounds. Breeding densities of 14.5 pairs per 100 ha were counted on the Deer Creek study area. INTRODUCTION Although Tuck (1972) and Sanderson (1977) provide extensive reports on the distribution and life history of Common Snipe in North America, no general assessment of breeding range and population status in California has appeared since Grinnell and Miller (1944). California supports both breeding populations and winter residents. The objectives of this study were (i) to provide an up-to-date description of the distribution of snipe in California during the breeding period, (ii) to describe activities of the birds on the breeding grounds, and (iii) to describe and assess methods of measuring population densities and monitoring population trends. STUDY AREAS Two study areas were used to gather detailed information on breeding ground activities. The primary area was Deer Creek Meadows which is located in northeastern Tehama County at an elevation of 1300 m. The study area covered 25 ha in 1979 and was expanded to 88 ha in 1980. Habitats ranged from well drained grass uplands to constantly wet "bogs". Bogs and very wet zones which support short-beaked sedge, Carex simulata, and beaked sedge, C. rostrata were most important to snipe. Beaked sedge dominates areas too boggy for cattle to graze. Stands of lodgepole pine, Pinus contorta murrayana, are found in very wet areas of the meadow. Most of the trees are dead. Cottongrass, Eriophorum sp., and bogbean, Menyanthes trifoliata, which are characteristic of northern fen communities (Tuck 1972) are also found here. By early June the only areas providing good nesting cover were boggy areas and marshy sites within the timber stands. ' Accepted tor publication February, 1984. Supported by the Accelerated Research Program for Migratory Upland Came Birds. ' Mr. Hofmann's present address is 1627 Benjamin Ct., Areata, CA 95521 POPULATION STUDIES OF COMMON SNIPE 69 A secondary study area was Mountain Meadows in western Tehama County at an elevation of 1500 m (Figure 1). The habitat gradually shifts from sedge marsh to sedge meadow to upland. Sedge marsh and sedge meadow are impor- tant for snipe (Tuck 1972). The dominant sedge of the meadow \s Carex simulata and the wetter areas near the lake are dominated by C. nebraskensis. Areas of northern mannagrass, Clyceria borealis, also occur in ditches and along the lake shore. Water levels at Mountain Meadows are highly variable in late spring when much of the area usually has dried out and is irrigated for cattle pasture. DEER CREEK MEADOWS MOUNTAIN MEADOWS FIGURE 1. Breeding range of Common Snipe in California. METHODS AND MATERIALS Early field work showed it was infeasible to locate and map all existing breeding habitat from the ground. Color infra-red film covering most of the snipe's breeding range in California was obtained from the U.S. Forest Services' 70 CALIFORNIA FISH AND GAME Remote Sensing Unit in San Francisco. Photographs were taken with a pano- ramic camera mounted in a U-2 high-altitude aircraft. Each frame covered a land area approximately 3.7 X 59.5 km. A color signature was developed for breeding habitat by studying known breeding grounds on the film. Individual frames were examined using this signature, together with field data, to locate known and potential breeding habitat. Areas were located and transferred to black and white ortho-photographic quads. Once the quad was completed, a planimeter was used to determine the acreage at each location. Known habitat is defined as any area for which there are recent records of use by snipe during the breeding season. Potential habitat is defined as any location which has the same signature but has not been ground-checked to determine actual use by snipe. The U.S. Fish and Wildlife Service system of classifying wetlands (Cowardin et al. 1979) was used to catagorize breeding habitat. The majority is Palustrine Emergent Wetland. This classification includes areas typically called marsh, meadow, fen, bog, slough, and prairie pothole. Adult vocalizations and displays aided us in locating territories, nests, and young. Territorial displays observed included winnowing, arched-wing, and dis- traction displays. Most vocalizations were the scaipe note and yakking (Tuck 1972, Williamson 1950). Breeding densities were determined by territory mapping. A taped recording of a snipes yakking call was played while walking transects through the area. As birds responded to the call their position was noted. If a bird flew to the location of the tape or performed overhead, the location was considered to be within the bird's territory. The location of the tape was considered to be beyond the snipe's territory if the bird responded but failed to fly to this location. The Deer Creek area was monitored in this manner during two breeding seasons. Three-tier mist nets with 10 cm stretched mesh were used to capture snipe for banding and color marking. Various parts of the plumage were dyed with picric acid and/or Rhodamine B for future identification. Specific patterns were used to identify individual birds throughout the breeding season. U.S. Fish and Wildlife Service leg bands were placed on all birds. Transects were walked on the Deer Creek study area following a period of intensive trapping and color marking. A Lincoln Index was used to calculate an estimated population. A driving transect, based on one used by Tuck (1972) in Canada, was estab- lished on the Mountain Meadows study area to test its value for collecting breeding population data (Figure 2). The transect consisted of eight stops at 0.8 km intervals. The observer recorded the number of birds heard winnowing and/or yakking during a 2 min period at each stop. The route was run four times during each check. Counts were made at 1 h before sunrise, at sunrise, and 0.5 h before and after sunset. The number of birds heard at each stop was recorded. When possible, counts were made once a week from April through mid-July. Chi-square tests were used to detect differences in winnowing and yakking activity. POPULATION STUDIES OF COMMON SNIPE 71 J' ;j" '•H.t.ci.'J ' ' "XO- !'.... "V,; I,,..' V.' ^ LEGEND ^^:X?^^; ■ r-s^'C - ;'-, ^ SCALE IN KM -^' ■ -•:'-<.^ ,'- , V. a. n '.•■'- ;-;v:\i:;; FOREST MEADOW AREA . WINNOWING COUNT STATION >-:i:<~\ FIGURE 2. Winnowing count stations on Mountain Meadows study area. RESULTS AND DISCUSSION Breeding Grounds Location Most of California's breeding snipe nest in the northeastern part of the state. The western boundary of the breeding range closely follows the western edge of the Cascade Range from the Oregon border south to the Sierra Nevada. It continues along the Sierra crest to Lake Tahoe and south along the eastern edge of the sierra through Mono county. The northern and eastern boundaries are the state lines (Figure 1 ). This delineation differs somewhat from that described by Grinnell and Miller (1944), which may represent changes in breeding range or merely the location of sites not previously recorded. This study extends the breeding range to the west in several areas of the state to include Scott Valley in western Siskiyou County; areas around Whitmore and Oak Run in south central Shasta County; Browns Valley, central Yuba County; and several isolated locations east of Sheridan in northwestern Placer County. Brep'"'ng habitat has been lost in most of Inyo County because of changes in agricultural practices caused by diversion of water for southern California. However, remnant breeding populations still exist; a clutch of eggs was collected ^- 72 CALIFORNIA FISH AND CAME near Olancha in southern Inyo County in 1971 by the Western Foundation of Vertebrate Zoology ( Kimball Garrett, pers. commun. ) . A juvenile and two adults were observed in May, 1983. Reports of isolated breeding activity in northwest- ern Los Angeles County and western San Bernardino County were found in the literature (Grinnell and Miller 1944). Most suitable habitats have been engulfed by urbanization. Infra-red film showed potential habitat near Lake Isabella, northeastern Kern County. Breeding activity was observed during a field check in May 1983. This finding leads us to believe that other areas may exist along the west slope of the Sierra. Breeding habitats were generally found between elevations of 750 m and 1 500 m. Isolated locations were recorded as low as 60 m to over 2000 m. Low elevation sites were located along the west slope of the Sierra Nevada outside the major breeding range. Successful nesting was documented at one isolated site in Yuba county at an elevation of approximately 150 m. Nesting also has been documented at higher elevations; 1 900 m at Kyburz Flat, Sierra County, and 2000 m on Sagehen Creek, Nevada County (Vern FHawthorne, pers. commun.). From the U-2 infra-red film we estimate there are 14,000 ha of known breeding habitat and 24,000 ha of potential breeding habitat within the breeding range (Figure 3). These totals could vary from year to year depending on rainfall and habitat conditions. Period of Use Snipe were first seen on the breeding grounds during the last half of March. The earliest sighting was March 15, 1978 at Deer Creek Meadows. By early April breeding activity was well underway throughout much of the range. Breeding activity continued through mid-July, 1980 when territorial displays ceased abruptly, coinciding with the hatch of late clutches and the onset of post- breeding molt by late nesting adults (Tuck 1972). Fall departures from the breeding grounds were not monitored. However, during the last week of August, 1980 an intensive banding and color marking effort was undertaken on Deer Creek Meadows. Subsequent flushing counts indicated a population of approxi- mately 69 birds. By the last week in September only 15 birds were counted. No birds were located at either study area during the winter. Wintering birds were found on a breeding area in Indian Valley, Plumas County. One bird banded at this site in September was collected there the following January, showing that some of the breeding population may not always migrate. A second bird banded at this site was reported shot the following April in Culiacan, Mexico. A total of 1 1 5 snipe was banded on the two study areas. Nine were recaptured at these locations in subsequent years indicating they tend to return from winter- ing grounds to specific breeding grounds. Population Densities The best indicator of territory, nests, or the presence of young is the behavior of the adults. Vocalizations and displays were the key to determining breeding population densities on Deer Creek Meadows. During the 1 980 breeding period, 1 3 territories were located on the 88 ha study area (Figure 4). This would indicate a breeding density of 14.5 pairs per 100 ha. This exceeds densities given by Tuck (1972) of 5.5-13.2 for sedge bog and POPULATION STUDIES OF COMMON SNIPE 73 3.5-7.7 for fen habitats in Canada. Our density figure represents the total number of breeding birds on the area for the entire season. Some of the late nesters were able to utilize habitat that had been defended by other snipe earlier in the year. Nests were located in eight of the 1 3 territories. New nests were started almost every week with the onset of incubation ranging from May 1 through the end of June. Based on hatching dates at Deer Creek Meadows and the ages of nine flightless juveniles captured at Mountain Meadows, sixty percent of the nesting activity occurred in May. The 25 ha area of lower Deer Creek Meadows counted in 1979 contained six pairs of snipe. The same area contained eight pairs in 1 980. The 1 979 density was 24 pairs per 100 ha and the 1980 density was 32 pairs per 100 ha. This area was the most heavily utilized portion of the meadow in both years because of the excellent nesting habitat and thus produced inflated densities when compared to the whole breeding ground. I - 199 Hectares Per 15 Quadrangle 200- 399 -' " '- 400-1000 Over 1000 FIGURE 3. Breeding habitat acreage density by 15 minute quadrangles. 74 CALIFORNIA FISH AND GAME ■s^'-J- O "^ % ^^ "3 A ^ K^-^^.-.-'^rOo SCALE IN METERS ] WET MARSH l^r^vj^t LODGEPOLE PINE 8 MARSH \- -"I SEDGE MARSH 0 {5 CONIFER FOREST C__]) BREEDING TERRITORY # CONFIRMED NEST SITE FIGURE 4. Locations of snipe breeding territories in Deer Creek Meadows, 1980. Winnowing Index Driving transects were run from April through mid-July. The first peak in winnowing activity occurred during the first week of April, probably indicating the arrival of females (Tuck 1 972 ) . Counts fluctuated up and down through April and May. A second peak occurred in June ( Figure 5 ) . This peak may result from the continuing territorial display by some adult males plus displays from yearlings that are just reaching breeding maturity. Irrigated pasture creates new breeding habitat late in the season and attracts unpaired snipe to establish territories. This type of habitat is common throughout the breeding range and is generally used for summer grazing by cattle. We found that winnowing counts at sunset were significantly higher than morning counts (X2 = 4.60, P<0.05). This agrees with Tucks (1972) findings and indicates this time period is best for conducting counts. Although the winnowing pattern through the breeding season was similar in 1979 and 1980 (Figure 5), the level of winnowing was significantly higher in 1980 (X^ = 13.79, P<0.05). This annual fluctuation has potential for use as a survey method to monitor breeding ground activity. Winnowing is primarily a male sexual display to attract the female. Yakking is done by both sexes to declare a territory (Tuck 1972). Yakking counts were relatively constant during all count periods (X2 = 0.35, P>0.05). Daily observa- tions for yakking and winnowing indicate lower variance in yakking counts throughout the day and during any count period except postsunrise. We believe that yakking counts may have value as a survey method to determine breeding pair densities. Further studies are needed to compare yakking counts to areas where territories have been mapped. POPULATION STUDIES OF COMMON SNIPE 75 1980 APRIL MAY JUNE JULY FIGURE 5. Post-sunset winnowing activity patterns on Mountain Meadows study area. ACKNOWLEDGMENTS This study was supported in part by the U.S. Fish and Wildlife Service with funds made available through the Accelerated Research Program for Migratory Upland Game Birds and in part by Pittman-Robertson W-47-R, Upland Game Investigations. We express our appreciation to j. Caylor and W. Salizar of the U.S. Forest Service for providing the color infra-red film and for training us in its use. We wish also to thank E. Cummings for his efforts in analyzing the statistical data and E. Ohara for preparing the figures. LITERATURE GITED Cowardin, L.M., V. Carter, S. Colet, and E. LaRoe. 1979. Classification of wetlands and deepwater habitats of the United States. U.S. Fish and Wildlife Service, FWS/OBS-79/31, 100 pp. Grinnell, ]., and A.M. Miller, 1944. The distribution of the birds of California. Cooper Ornithological Club, Pacific Coast Avifauna. 27:149-150. Sanderson, G. C. (editor), 1977. Management of migratory shore and upland game birds in North America. International Assoc, of Fish and Wildl. Agencies, Washington D.C. 358pp. Tuck, L. M. 1972. The snipes: A study of the genus (Capella), Canadian Wildlife Service Monograph Series No. 5. 429 pp. Williamson, K. 1950. The distraction displays of Faeroe Snipe. Ibis, 92:66-74. 76 CALIFORNIA FISH AND CAME Calif. Fish and Came 71 (2): 76-87 1985 GROWTH, FOOD, AND HABITAT OF AGE 0 SMALL-MOUTH BASS IN CLAIR ENGLE RESERVOIR, CALIFORNIA^ DANIEL OKOTH OKEYO AND THOMAS J. HASSLER California Cooperative Fishery Research Unit ' Humboldt State University, Areata, CA 95521 A total of 342 age 0 smallmouth bass, Micropterus dolomieui, from Clair Engle Reservoir, Trinity County, were collected with seines from July through September 1979 as part of growth, diet, and habitat studies. Mean length in mid-September was 84 mm; a relatively low value. Protected habitat areas were favored during spring and early summer. Fish tended to move to more exposed habitats as they became larger and weather conditions moderated. Favored bottom substrates included shale, rocky-rubble, sand and gravel, and areas with stumps and submerged logs. No bass were collected in areas with exclusively mud bottoms. Aquatic dipterans (primarily chironomid larvae and pupae) dominated the age 0 bass diet. INTRODUCTION Clair Engle Reservoir, formed in 1960 by the closure of Trinity Dam, on the Trinity River, is part of the U.S. Bureau of Reclamation Central Valley Project in northern California. Soon after impoundment a fishery developed for lar- gemouth bass, Micropterus salmoides, and smallmouth bass, M. dolomieui. Bass were introduced when old dredge ponds were flooded during reservoir filling, and both species established naturally reproducing populations. The smallmouth bass fishery is the larger, and fishing effort for this species has increased dramati- cally over the years. Other species contributing significantly to the fishery in- clude brown trout, Salmo trutta, rainbow trout, 5. gairdneri, and kokanee salmon, Oncorhynchus nerka. As bass populations increased, a trophy smallmouth bass fishery developed. To prevent over-exploitation of the smallmouth bass population, the California Department of Fish and Game imposed a 30.5-cm minimum length limit in 1976. Although this size limit has been successful elsewhere for conserving small- mouth bass populations (Surber 1969), it is not clear that this regulation alone will be sufficient to maintain a quality fishery in Clair Engle Reservoir. Preliminary data indicated rapid growth of smallmouth bass in the reservoir (J. Thomas, unpubl. data), although Coleman (1978) found that the reservoir was cold and unproductive, with low standing crops of zooplankton. Knowledge of the food, growth, and habitat of age 0 smallmouth bass in this reservoir should enable the refinement of the management plan for the population. STUDY AREA Clair Engle Reservoir is about 40 km northwest of Redding, California, on the upper reaches of the Trinity River, at an elevation of 724 m above mean sea level. The reservoir has a maximum capacity of 3.1 billion m ^ of water; it is 30 km long and 0.8 to 3.2 km wide, with a shoreline of 240 km and a surface area of 66 km 2. The reservoir is 136 m deep at the dam and is deep throughout most ' Accepted for publication March 1984. ^ Cooperating agencies are the Humboldt State University, the California Department of Fish and Game and the U.S. Fish and Wildlife Service. AGE 0 SMALLMOUTH BASS 77 of its length. The reservoir is considered oligotrophic and is similar to other deep mountain lakes in California (Coleman 1978). It has seven major tributaries: Trinity River, East Fork Trinity River, Swift Creek, Feeney Creek, Papoose Creek, East Fork Stuart Fork, Stuart Fork. Most of the inflow is snowmelt from nearby mountains. The steep banks are devoid of aquatic plants and most trees were removed before the reservoir was filled. METHODS Nine stations were sampled with seines at 2-wk intervals during April-June 1979 and April-May 1980, and weekly during July-September 1979 (Figure 1). Stations were selected on the basis of preliminary seine surveys and the most productive seinable areas within different habitats were assigned station num- bers. Stations were classified into three habitat "types", based on a visual de- scription of the sampling areas. Habitat 1 (stations 2, 6 and 7) was characteristic of protected areas near major tributaries; habitat 2 (stations 4 and 5) was characeristic of sheltered, gently sloping littoral areas; and habitat 3 (stations 3, 8, and 9) was characteristic of unprotected steeply sloping littoral areas. Station 1 (a representative of habitat 3) was sampled only once in early July and was not included in the fish growth and food analyses by habitat type. Stations associated with streams ( habitat 1 ) , were cooler than other areas and were protected from winds. Some macrophytes and flood'^d terrestrial vegeta- tion were in the areas when water levels were high. The bottom substrate consisted of sandy-gravel, flooded weeds, dead small rooted shrubs, and a few submerged logs and rock piles. Turbidity was low during the sample period. The sheltered flat areas (habitat 2) were protected from heavy winds and waves, since they were in small bays with narrow outlet channels. Aquatic plants were scarce, and at high water levels little terrestrial vegetation was flooded. Tree stumps were the major cover. Bottom substrate ranged from a sandy-mud mixture to rocky rubble. Water in this area was moderately turbid even during fairly calm weather. The open water areas (habitat 3) were steeply sloped with shale, gravel, or rock shorelines and little vegetation. During windy periods the shoreline was subject to erosion by wave action, and nearshore turbidity was high. Surface water temperature was taken with a pocket thermometer during each sampling period at the station where data collection began. Age 0 smallmouth bass were collected with two seines, one 9.1 by 1.2 m with 3.2-mm mesh, and another 15.2 by 1.8 m, with 5.9-mm mesh (bar measure). Both seines were used during each sampling period. Fish were preserved in 10% buffered formalin and later measured fork length (fl), (to the nearest mil- limetre) and weighed (to the nearest gram) 30 s after they were blotted on clean filter paper. Mean lengths and weights of bass were compared by habitat and month using the Student-Newman-Keuls procedure (Sokal and Rohlf 1969). Total bass catch, by habitat and time, were compared using Friedman's test (Langly 1971). We determined length-weight relation, W = aL^, using the computer program "Growth" (Mawson and Reed 1969), as modified by Collins (1977), where: W = weight in grams, /. = fl in millimeters, and a and b are constants. Fork length was converted to total length (tl) by the formula, tl = 1.04 fl (Fry and Watt 1957). 78 CALIFORNIA FISH AND CAME TRINITY RIVER EAST FORK 3 TRINITY RIVEP 5 FEENY CREEK SCAUE: icm = 1267m 0 1 2 3 4 5 6 I I 1 — I — 1 1 i- KiUOMETERS 6 PAPOOSE CREEK FICURE 1. Clair Engle Reservoir California, showing sampling stations in three types of habitats: (1 ) protected areas near major tributaries (Stations 2, 6, and 7); (2) sheltered gently sloping littoral areas (Stations 4, and 5); and (3) unprotected steeply sloping littoral areas (Stations 1, 3, 8, and 9). Stomach contents for each fish were examined microscopically and food items identified using keys published by Pennak (1953); Fernald and Shepard (1955); Usinger (1963); Edmondson (1966); Comstock (1972); Borr, Delong and Triplehorn (1976); and Leumkuhl (1979). Unidentified food material and empty stomachs were recorded. Abundance of food items in each fish stomach was characterized by three methods: volumetric, numerical, and frequency of occurrence (Larimore 1957, Windell 1971,Clady 1974, George and Hadley 1979). Major food groups (those 0.05 ml or more in total volume and representing more than 0.1% by number) AGE 0 SMALLMOUTH BASS 79 were tabulated by habitat and time of collection. Volumes of benthic organisms, fish, and aquatic and terrestrial insects were measured by water displacement in a calibrated centrifuge tube. Volumes of zooplankton, ostracods, and amphi- pods were estimated by making several measurements for each species and computing an average volume per individual of a species, and then multiplying by the number of individuals of that species per stomach (Langdon 1979). Frequency of occurrence consisted of the number of stomachs containing food of a given group, expressed as a percentage of the total of 221 full stomachs that were examined (Windell and Bowen 1979). Stomach contents from each fish also were evaluated by using the Index of Relative Importance (IRI: Pinkas, Oliphant, and Iverson 1971), for each food item: IRI = {N + V)FO, where N — percentage of total number, V = percent- age of total volume, and FO = percentage frequency of occurrence. RESULTS Catch By Habitat A total of 342 age 0 smallmouth bass were collected from all habitats (Table 1). Age 0 bass were caught only during July-September 1979. The catch de- creased significantly from 208 in July to 30 fish in September P<0.05) but did not differ significantly by habitat type. Age 0 bass were caught throughout the reservoir in rocky-rubble areas and in areas with stumps and vegetation, but no bass were caught in areas with mud bottoms. Reservoir water level was max- imum and stable from mid-May to mid-July and all stations were seinable. Water level dropped 9.5 m from mid-July through September and most stations were difficult to seine. TABLE 1. Numbers of Young-of-the-Year Smallmouth Bass Collected in Different Habitats from Clair Engle Reservoir, California, Summer 1979. Habitat r 2" Total " Protected areas near major tributaries. '' Sheltered, gently sloping littoral areas. ' Unprotected steeply sloping littoral areas. Growth Mean fl of age 0 smallmouth bass increased from 32 mm in early July to 84 mm by mid-September and mean weight from 0.6 g to 8.7 g (Figure 2). Age 0 bass from the three habitats averaged the same size in July (Table 2). Fish captured in habitat 1 during August were significantly smaller than fish from habitats 2 and 3 (P<0.05; mean 54.3 mm fl and 2.4 g versus 63.1 mm and 4.0 g). Fish captured in habitat 1 during September were significantly shorter than fish from habitats 2 and 3 (P<0.05; mean 72 mm versus 78.4 mm) but were significantly lighter only than fish from habitat 3 ( P < 0.05; mean 5.9 g versus 7.3 g). The allometric length-weight relation was as follows: weight = 1.790 X 10 -' X Length ''^, r = 0.932 (Figure 3). July August September 107 39 11 55 27 8 46 38 11 208 104 30 80 CALIFORNIA FISH AND GAME 100- 80 E E o z llJ O li. iLl CD < liJ > < 60- 40- FORK LENGTH / / WEIGHT 158 / 20. 50 ^:r -10 8 -6 -4 1 ■ 1 JULY AUGUST SEPTEMBER 0 h- X UJ 111 q: UJ > < -2 FIGURE 2. Size of young-of-the-year smallmouth bass from Clair Engle Reservoir California, July- September 1979. Mean ± standard error; numbers between weight and length curves show numbers of fish in each collection. TABLE 2. Mean Size ol California, Su Young-of- mmer 1979 July •the-1 ['ear Sm allmouth E August tass from Clair Engle Re September serve Habitat Length (mm) Weight (g) N Length (mm) Weight (g) N Length Weight (mm) (g) N 1 2 3 42.1 46.1 46.6 1.2 1.5 1.5 107 55 23 54.3° 62.6 63.6 2.4" 3.7 4.3 39 27 38 72.0° 5.9' 77.4 6.7 79.5 7.3 11 8 11 ° Significantly shorter than fish from habitats 2 and 3 (SNK; P<0.05). ''Significantly lighter than fish from habitats 2 and 3 (SNK; P<0.05). 'Significantly lighter than fish from habitat 3 (SNK, P<0.05). Food Of the 327 fish stomachs collected, 96% contained food. Food was analyzed only from the 221 fish (68% of the total) that had full stomachs. AGE 0 SMALLMOUTH BASS 81 10 5 70- 3.6- W = 1.790 % 10"^ X l2 948 r = 0.932 n = 342 0 I- •• 17.0 33.0 L E 48.9 N G T H 649 eo.e 96.0 ( mm) FIGURE 3. Length-weight relation of 342 young-of-the-year smallmouth bass from Clair Engle Reservoir California, July-September 1979. Aquatic dipterans dominated the diet of age 0 smallmouth bass by volume, number, and frequency of occurrence (Table 3 ) . Chironomid larvae dominated the food items by volume (49.5%), followed by Ephemeroptera (15.9%) — mostly nymphs of Baetidae. Chironomid pupae, the second most abundant dipteran, v^ere the third most abundant food item by volume (11.0%). These three groups accounted for 76.5% of the volume of food eaten by age 0 bass. Chironomid larvae dominated the diet by numbers (28.0%) and chirono- mid pupae ranked third numerically (15.0%). The copepod, Diaptomus francis- canus, ranked second numerically (22.2%), and the cladoceran, Diaphanasoma brachyurum, ranked fourth (12.8%). The other 33 food items accounted for only 22.8% of the total number of items eaten. Frequency of occurrence for larvae and pupae of Chironomidae were 83.7 and 75.6%, respectively. They were followed by Cladocera, Ephemeroptera, and Copepoda. Indices of Relative Importance and percentage IRI were determined for the 12 most important food categories (Table 4). The most important age 0 small- mouth bass food was chironomid larvae and pupae (IRI, 42 and 17%, respec- tively). The next two most important food items were Diaptomus franciscanus and Diaphanasoma brachyurum. These four food organisms accounted for at least 84% of the IRI each month. Chironomid larvae were the most important age 0 smallmouth bass food in all habitats in July, and in habitats 2 and 3 in August (Table 4). Eurycercus lamellatus was the most important food item in August in habitat 1. The most important food organisms in September were Diaptomus franciscanus in habitat 1, Diaphanasoma brachyurum in habitat 2, and chironomid pupae in habitat 3. 82 CALIFORNIA FISH AND CAME TABLE 3. Stomach Contents of 221 Young-of-the-Year Smallmouth Bass from Clair Engle Reservoir, California, July-September 1979. Voi lume Nu mber Occurrence Food Items ml % N % Frequency % Ceriodaphnia laticaudata J" J 38 0.2 3 1.4 Chydorus sphaericus T T 105 0.5 34 15.4 Daphnia galeata mendotae 0.14 1.1 1392 6.3 17 7.7 Daphnia pulex 0.08 0.6 548 2.4 55 24.9 Diaphanasoma brachyurum 0.28 2.2 2770 12.6 108 48.9 Eurycercus lamellatus 0.39 3.1 1951 8.9 122 55.2 Polyphemus pediculus T T 215 1.0 4 1.8 Diaptomus franciscanus 0.49 3.9 4900 22.2 64 29.0 Cyclops bicuspidatus T T 159 0.7 39 17.6 Ostracoda T T 2 T 0.5 Amphipoda 0.08 0.6 109 0.5 15 6.8 Heptageniidae (nymphs) T T 1 T 0.5 Caenidae (nymphs) T T 1 T 0.5 Baetidae (nymphs) 1.98 15.9 238 1.1 80 36.2 Comphidae (nymphs) 0.13 1.0 9 T 0.5 Libellulidae (nymphs) 0.14 1.1 5 T 1.4 Zygoptera— damselflies 0.51 4.1 41 0.2 30 13.6 Corixidae T T 5 T 1.4 Leptoceri 0.02 0.2 16 0.1 2.3 Chironomidae (larvae) 6.17 49.5 6171 28.0 185 83.7 Chironomidae (pupae) 1.37 11.0 3294 15.0 167 75.6 Dixidae T T 1 T 0.5 Muscidae (larvae) T T 2 T 0.5 Brachycera T T 1 T 0.5 Corydalus sp. (larvae) 0.16 1.3 8 T 3.2 Dytiscidae (larvae) T T 3 T 1.4 Cleridae T T 1 T 0.5 Eupelmidae T T 2 T 0.5 Formicoidae T T 1 T 0.5 Chalcidoidae T T 1 T 0.5 Emphididae T T 10 T 1.4 Mycetophilidae T T 1 T 0.5 Cicadellidae — leafhoppers T T 1 T 0.5 Psyllidae (Chermidae) T T 2 T 0.5 Delphacidae T T 1 T 0.5 Ictalurus sp. 0.17 1.4 5 T 1.4 Green Sunfish 0.17 1.4 5 T 1.4 (Lepomis cyanellus) 0.06 0.5 2 T 0.9 Trout or Kokanee 0.30 2.4 12 0.1 8 3.6 Unidentifiable items T T — 1 Total 12.47 99.9 22024 99.8 (<0.05 ml or< 0.1%) The number of food items in the stomachs of young fish decreased from July to September. However, the size of the organisms eaten increased. For example, as bass increased in size during the season they ate larger food items such as fish and damselflies. ACE 0 SMALLMOUTH BASS 83 o > v> 60 C If) CO 3 O E m 60 > V O T}- oo —^ CTi . — >— ■^ I — rN rNi I— I— OOOv£>|— O O' — rNiOLnu-iuiOOOO'^Orsi 0-) ' — a^ ro 1— 1 — rs CO T >— f^ ^ <— rnroOi — rsli — O' — 0^ ^ CO >^ CO CT^ — . — LT) r^ rn m I— O I— O ^ »— ^rnLOr— LTtOTj-rorsi LTii — cor^v^i — rsir^>>DrNi <-^ >— ■* i\ r— m CO -^ O ^ O 5f^ O O O 'T COt"^-^*— OO^rnOto LOOOO^COO^ror^ -X) vD CO 01 O k 22S o c Of u c a; a. k a> o h» ao^ E ^ U 01 > E F «« 3 u l/i QC » W o C k M o 0) »^ ■o CO ^ I— I— O I— ^ O O ^r^^DLno*x>LnLnc:>OOOOco ^Mi — CO' — rn-X)*:!" vXiO^ i — »— CT^ ' — LO o ^^ — . ^^ — , — , CO Lo O I— >— r^l— T— Ol— ooi— 'N o ^ O O 1^ O^ >— Ln rorvjmcoco-^ O^*^ LOLTir^i LO. — rsl o a^ CM ro O Ol Q. iu CD Ol TO it 2 ^ lb (LI p E TO 5 ™ ■^ C OJ .TO .TO U U Cl Q c :3 ■ TO O n3 (^ — - Q. ro Q02«i "D "O coQMCii— <_tiOl— 1 a T3 c 5 c 01 nj ■g ic Q. E o u c c 01 a. £ c >— c-Mui'g-co^J^roO--, 0^OO^^OC>OO.-^g CO •* T— CM t^ CM CO LO CO >X) 3 O O c 3 <0 00 ■o c m « eo < §- S ■s 5 t 3 I -H^ -C •^ OO ro CO ■<*■ r- coor\>sOa^roco^n "— ■^ <^ CM .— .— CO rslmT^Lnv£)l\coo^O•— CM o 94 CALIFORNIA FISH AND GAME 600 500 400 ^300 IT O 200 100 • Thomes Creek D Merced River X Hot Creek A Cottonwood Creek O North Fork Feother River 6 7 AGE IN YEARS 10 FIGURE 2. Comparison of growth curves of Sacramento suckers from Hat Creek, Cottonwood Creek, Merced River, North Fork Feather River and Thomes Creek. TABLE 2. Jolly-Seber (Seber 1973) Spawning Population Estimates of Sacramento Suckers from Thomes Creek, Tehama County, California, 1981 Sample period Number of ending fish tagged 12-09-80 0 12-19-80 26 01-08-81 44 01-18-81 32 01-28-81 66 02-17-81 210 02-27-81 30 03-09-81 722 03-19-81 473 03-29-81 51 04-08-81 280 04-18-81 115 04-28-81 16 05-08-81 4 05-18-81 13 05-28-81 0 06-07-81 0 Totals 2,081 Number of Population tags recovered estimate 0 2 440 3 715 1 8,808 1 22,083 1 3,634 2 241,481 5 55,000 7 1,938 8 41,168 4 8,818 1 1,548 1 5 4 13 1 10 0 0 41 SACRAMENTO SUCKER LIFE HISTORY 95 UJ o a: UJ KJV 1 1 1 1 I I 80 -- - 60 - / \ - 40 - / \ A - 20 n 1 H -^ 1 1 _^ I December January February March 1981 April May June FIGURE 3. Percent ripe Sacramento suckers from Thomes Creek, Tehama County, 1981. During the spawning migration, the sex of 2,086 adult suckers was identified. Six hundred twenty-eight of these were females, while 1,428 were males, repre- senting a sex ratio of 1:2.17. The mean fork length of females (428 mm) was significantly larger than males (383 mm) (p <0.05) (Figure 4). In Cottonwood Creek, male Sacramento suckers average 396 mm while females averaged 431 mm (Dept. Fish and Game, Contract Services Section files). Females of both white suckers and longnose suckers averaged larger than males (Elsey 1946, Harris 1962, Geen et al. 1966). Age Structure and Sexual Maturity The scales of 2,000 spawning suckers were examined and assigned ages and number of spawning checks (Table 3). The spawning population consisted of males aged 4 through 9 and females aged 4 through 12 (Table 3). For males, ages 5 and 6 composed the majority of spawners, while spawning females were mainly composed of ages 6 and 7. The age-frequency was somewhat similar in distribution and character to the length-frequency of spawning adult suckers, suggesting that assignment of ages was fairly accurate and that length and age in Sacramento suckers are closely related. Spawning checks were observed in 89% of the males and 96% of the females. At least half of the population spawned twice, while many fish spawned up to four times (Table 3). Geen ef a/. (1966) showed that longnose and white suckers are repeat spawners. The data showed that sexual maturity can be attained at age 4 (8%), but most suckers attained sexual maturity at age 5 or 6 (Table 4). Moyle (1976) states that the Sacramento sucker can mature sexually at 4 or 5 yr, while the longnose sucker can mature at 2 or 3 yrof age (Hayes 1956). Brown and Graham (1954) found that longnose suckers usually mature at age 4, whereas white suckers generally mature in their third or fourth year (McCrimmon and Berst 1961). Campbell (1935) showed that white suckers from Waskesiu Lake, Saskatche- wan, matured as late as ages 6 to 9. The oldest any fish first became sexually mature for my population was at age 7. This occurred for less than 4% of the population. 96 CALIFORNIA FISH AND CAME "^ r 180 170 160 1— 150 140 t- 130 — 120 1 110 k 100 90 80 - 70 60 SO 40 30 20 10 275 ± MALES X FL " 393fnfTi NX> 000 m r.4 ■^ O r^ ■^ rn o rsj v^ O r< o .— ■ m ^ cr- rN LA r\ rsi 0^ p 5 CO O •— CM m ■^ LO 0 1— LO u-1 p 0 0 •— LTl 1 \-n p 0 1 0 *"" u-1 ■* ■* ro 0 <~si .— ' t' IT; m h^ ^' vT) CO v-D LJI vD U-) 0-. ■^ 0 ^^i <-si ' p rsj rN Oi r^ O^ O^ <-si rsi ■* 1^ •^ LO ^ 0-; rN ro ■^. Ln a^ T— ' 0 r-^ 0»— fNr'i'^Lnv^r^ O 98 CALIFORNIA FISH AND GAME TABLE 4. Age at Which First Spawning Check was Observed in Scales from Sacramento Suciters from Thomes Creel<, 1981 Sex Female Male Weighted Percent Age (percent composition) 4+ 5+ 6+ 7+ 7.7 49.2 37.2 5.9 8.3 58.3 31.1 2.2 8.1 55.5 33.0 3.4 Fecundity The egg counts for 50 females (X/fl = 429 mm) were highly variable with a mean of 16,358 and a range of 9,687 to 32,335 (Table 5). Sacramento suckers ranging in size from 280 mm to 380 mm fl from Alpine Lake, Marin County, contained 4,720 to 10,932 eggs (Burns 1966a). Sacramento suckers from Cotton- wood Creek had egg counts ranging from 10,840 to 22,636 for 17 fish ranging in size between 41 1 mm to 485 mm fl ( Dept. Fish and Game, Contract Services Section files). Although the trend appears to be for longer and heavier fish to have more eggs, I found no strong correlation between any body measurement and egg counts or ovary weight for suckers from Thomes Creek (Figure 5). In Tahoe suckers, Catostomus tahoensis, fecundity was also highly variable (Will- srud 1971 ), and had a weak linear correlation with fork length (Moyle 1976). TABLE 5. Fecundity of Sacramento Suckers from Thomes Creek, Tehama County, 1981 By Length Interval Fork length (mm) Interval 300-349 350-399 400^9 450499 Grand Mean or Total Mean N Number of eggs Range Weight (g) By Weight Interval Number of eggs 326 382 427 403 1 6 30 13 9687-16190 11350-21614 15488-32335 Mean 10318 12005 15668 20437 Interval 400- 499 600- 799 800-999 1000-1199 1200-1399 1400-1599 429 50 9687-32335 16358 550-1588 Mean 550 729 905 1076 12515 1588 987 N 1 9 16 15 8 _1_ 50 Range 9687-18741 10624-22672 11527-21614 18098-22741 Mean 10318 14666 15179 17656 20136 32335 9687-32335 16358 Sexual Dimorphism and Spawning Act Sacramento suckers when not in spawning condition are dark brown, green- ish, or almost black on their dorsal side, fading to a light or golden brown near the ventral side. During the spawning season, males developed small bumps or nuptial tubercles on their anal, pelvic, and lower caudal fins and on the ventral side of the caudal peduncle. As spawning time approached, these tubercles became more pronounced. During peak spawning, the nuptial tubercles were at their fullest development and appeared as bumpy white dots on the fish's surface. Nuptial tubercles are presumably used by the males to "grip" the female during spawning (Branson 1961). I was unable to verify this claim although I observed males in close contact with the female during spawning. In addition to the nuptial tubercles, the males developed a broad black or dark-brown stripe along the lateral line. This stripe was most prominent during spawning. SACRAMENTO SUCKER LIFE HISTORY 99 -30000 o 1^20000 10000 _ 30000 - o o "^20000 10000 •p 30 000 J 20000 10000 Y = 84 3X-I9437 N=4I R = 0.50 . A - / •.::/ 'A* 1 . A \ • / • • ■ 250 ^200 5 150 > o S 100 50 100 200 300 400 Fork Length (mm) Y = l lx-3 N = 4I R=0 6l 40 / -i ^ — ■ • A •, 500 100 200 300 400 500 Fork Length (mm) 1 Y=l4 7x + I966 N=4I y R=059 y^ ^ y^ • ' ..^ • y^ ' • ' • y^ ' 500 1000 1500 Totol Weight of Fish (g) 2000 500 1000 1500 2000 Total Weight of Fish(g) Y=0.8x + I027 N = 40 / R = 0 .iJU •/^ /^ 10000 20000 30000 Left Ovory Count FIGURE 5. Linear regressions of fecundity, ovary weight and body measurements of Sacramento suckers from Thomes Creek, Tehama County, 1981. During the spawning migration, some females were observed with well-devel- oped pearl organs. They appeared as small pearl-like spheres on the anal, caudal, and pelvic fins. Very few males were observed with pearl organs. The spawning act of Sacramento suckers is similar to that of the white sucker. Sacramento suckers generally spawn on shallow riffles in groups comprised usually of six to seven males centered around one or two females. Spawnings usually lasted no longer than 2 h. There also seems to be no preference for time of day or amount of light. Eggs were adhesive, but usually they did not stick to the substrate; rather they picked up small bits of debris that allowed them to roll along the bottom with the current until they settled out among the interstices of the substrate or in the shallow stream margins where there was little or no current. 100 CALIFORNIA FISH AND GAME Juvenile Emigration The bulk of the juvenile and larval sucker emigration from Thomes Creek to the Sacramento River occurred mostly during about a 3-wk period in late May and early June, but young emigrated in low numbers throughout the sampling period (Figure 6). Mean lengths and the length frequency distribution from February to April remained similar (Figure 7). These fish were probably spawned during the previous spring and remained in the creek throughout the summer until discharge was high enough for them to migrate downstream. 10 000 7500 5000 J 2500 5 -i 1 1 1 1 1 1 1 1 1 1 1 1 1 1 I I I I r Upper Ronge Mean Low Ronge Temperoture- Number of Fish I I I I I I I I I I L I I I I I I I I U 35 30 25 S. 20 E _ 10 _ 5 23456789 10 i MARCH APRIL MAY 12 13 14 15 16 17 18 19 20 JUNE JULY FIGURE 6. Weekly fyke net catches of juvenile Sacramento suckers emigrating from Thomes Creek to Sacramento River, 1981. Larval suckers were first observed in the upper reaches of the main stem and tributaries in late April, but none was caught near the mouth until mid-May. The emigration at that time increased rapidly until the weekly fyke net catch peaked at over 7,500 fish during the first week of June (Figure 6). After the first week of June, catches diminished rapidly, but emigration continued for about 4 wk until there was no measurable discharge at the mouth of Thomes Creek. The first larval suckers were observed in the creek about 4 to 5 wk after the first ripe adult suckers were observed. In addition, the peak in juvenile emigra- tion occurred approximately 4 to 5 wk following the peak in spawning activity. Moyle (1976) and Burns (1966a) estimated that Sacramento suckers hatch in about 4 wk. This concurs with my observations. Resident Fish Sacramento suckers were found at all 12 stations during the summer, but population and biomass estimates varied widely (Table 6). At stations 1-11 suckers were usually the second most abundant species by numbers, and com- prised from 1.5% to 39.6% of the total biomass. They were the most abundant species by number and biomass at Station 12. At stations 1-11 Sacramento squawfish was the most abundant species, with California roach, Lavinia sym- metricus, and hardhead, Mylopharodon conocephalus, also present in signifi- cant numbers. Other fish captured in these stations included green sunfish, Lepomis cyanellus; bluegill, Lepomis macrochirus; largemouth bass, Microterus SACRAMENTO SUCKER LIFE HISTORY 101 Ol L 20 -1 T March N=I08 10 — //^////?-77^, ..... 30 — O 0. O 20 O hi O UJ 10 & 1 ' May ^ N=ll,323 i - ? 1 1 1 1 > 1 1 m i '//. P v/. V/h-r^ , 1 1 1 1 . 20 — 10 — 1 1 1 II July N»43 , , , ttwA 1 7////. 1 1 1 1 1 {/////////A 10 20 30 40 50 60 70 80 FORK LENGTH (mm) 90 100 no FIGURE 7. Length-frequency of juvenile Sacramento suckers emigrating from Thomes Creek, to the Sacramento River, 1981. Percent of Rivsr Population estimate (95% C.I.) Biomass total fish kilometre 8/m' 8/m' biomass 7.2 16 (13-19) 1.2 5.2 1.5 12.1 196 (191-200) 1.5 10.0 15.7 21.1 58 (5^59) 0.9 2.3 11.0 21.8 210 (208-214) 5,9 42.2 27.6 22.5 36 (1-89) 2.9 6.8 7.1 33.2 21 (20-22) 4.9 19.6 39.6 39.1 9 (8-10) 0.1 0.4 3.8 41,8 9 (8-10) 0.5 2.9 8.4 44.9 19(16-21) 1.1 7.0 25.5 45.7 44 (34-54) 2.1 7.9 6.3 46,7 5 (5-5) 0.2 0.7 9,9 60.5 132 (119-146) 5.3 20.7 66,8 102 CALIFORNIA FISH AND CAME salmoides; hitch, Lavinia exilicauda; speckled dace, Rhinichthys osculus; carp, Cyprinus carpio; goldfish, Carassius auratus; prickly sculpin, Cottus asper; tule perch, Hysterocarpus traski; and rainbow trout, Salmo gairdneri. For all stations nongame fish were the most prevalent in numbers and biomass. TABLE 6. Population and Biomass Estimates of Resident Sacramento Suckers in Selected Sections of Thomes Creek, Tehama County, 1981 Station number 1 2 3 4 5 6 7 8 9 10 11 12 Most suckers sampled in my survey were juveniles; only a few spent or moribund adults were captured. In a survey of fishes in streams of the Sierra Nevada foothills, Moyle and Nichols (1974) found that a majority of Sacra- mento suckers were also juveniles, and that these small intermittent streams serve as nursery areas while the adults live in larger streams and reservoirs. In my study this was also the case where adults resided in the Sacramento River and ascended Thomes Creek only to spawn. Most of the juveniles emigrat- ed immediately after hatching and only those that are stranded or elected to stay were captured during the summer resident fish sampling. Length-Weight Relationship The length-weight relationship calculated for 246 suckers of all sizes was curvilinear and is described by the equation: Logio weight = -4.9246 + 2.9962 Log,o length (r = .99) (Figure 8). For this relationship, ripe or spent adult fish were not used. A separate regression for each sex and stage of reproduction (green, ripe, or spent) for adult fish was calculated and compared (Table 7) . Analysis of covari- ance showed that the slopes and intercepts of all regressions were not signifi- cantly different (P < .05). TABLE 7. Linear Regressions of the Length-Weight (Log,o) Relationships of Adult Sacra- mento Suckers from Thomes Creek, Tehama County, 1981 Sex F M F M F M Spawning Number Correlation condition Y-intercept Slope offish coefficient Green -3.109 2.308 159 0.80 Green -2.924 2.227 176 0.76 Ripe -3.401 2.417 111 0.76 Ripe -3.390 2.401 364 0.76 Spent -3.185 2.304 158 0.82 Spent -3.197 2.312 37 0.71 1200 1000 800 X C9 * 400 200 SACRAMENTO SUCKER LIFE HISTORY r ^ 103 Logio W= -4 925 + 2.996 LoQiq L N = 246 R=.99 100 200 250 300 FORK LENGTH (mm) 350 490 FIGURE 8. Length-weight relationship of Sacramento suckers in Thomes Creek, Tehama County, 1981. The coefficient of condition was calculated for as many representative in- dividuals per length group as possible (Table 8). Some groups and individuals were not available, yielding wide-ranging values, and, in some cases, no data. Therefore, a calculated value for each length group was derived from the length- weight equation. The calculated values represent the coefficient of condition for the midpoint of the length interval. The calculated values show that the coeffi- cient decreases very slightly with increased length. TABLE 8. Coefficient of Condition (K) for Sacramento Suckers, Thomes Creek, Tehama County, 1981 Fork length (mm) 4(M9 50-99 100-149 150-199 200-249 250-299 300-349 350-399 400-449 450-499 Mean Calculated Empirical Calculated weight weight — — N (g) (8) K K 22 1.29 1.03 1.3450 1.1724 93 4.51 4.83 1.1719 1.1681 43 16.65 22.53 1.1372 1.1675 6 63.67 61.98 1.1211 1.1665 7 142.14 131.86 1.1846 1.1654 3 215.00 240.85 1.0802 1.1645 17 410.00 397.65 1.2147 1.1637 154 659.43 610.90 1.1948 1.1631 186 874.88 889.29 1.1489 1.1625 34 1092.36 1241.47 1'.1089 1.1621 Diet The diet of Sacramento suckers in Thomes Creek did not change seasonally throughout a 1-yr period (Table 9). Algae and detritus were the most prevalent food items (45%) while sand composed 43% of the stomach contents. Insects, 104 CALIFORNIA FISH AND GAME mainly larval plecopterans and dipterans, made up less than 10% of the diet. There was no pattern to the composition of insects consumed. Therefore, it is likely insects were only incidental food items. TABLE 9. The Seasonal Diet Composition of Sacramento Suckers from Thomes Creek, Te- hama County, California, 1981 Percent Composition by Weight December March June September Food item to February to May to August to November Ephemeroptera 2.13 0.01 0.26 0.73 Odonata - - - 0.22 Plecoptera 15.86 - 0.03 1.19 Tricoptera 2.68 0.01 0.89 0.02 Hymenoptera - - - 0.07 Coleoptera - 0.02 - 0.17 Diptera 8.25 0.02 1.05 4.25 Algae and Detritus 33.40 50.13 51.39 36.10 Sand 34.57 49.70 45.55 54.57 Unidentified 3.11 o.n 0.83 2.68 Number of Stomachs Examined 40 40 40 40 Number of Empty Stomachs 7 18 5 6 Brauer (1971) found that algae was the most prevalent food item in larger suckers. In addition, Moyle (1976) states that the bulk of their diet is algae, diatoms and detritus. Hauser (1969) showed that mountain suckers ate mostly diatoms and algae. CONCLUSIONS Sacramento suckers have adapted well to the intermittent nature of Thomes Creek. Adults migrate upstream to spawn during high water and eventually the young hatch and the majority of them emigrate to the Sacramento River before low-flow periods restrict their downstream emigration. Hence, these fish utilize spawning habitat in intermittent streams and make use of habitat not normally available to other fish during short periods of rainfall. I was not able to quantify the importance of suckers in relation to other species of fish and wildlife that may compete with or use them as food. Such studies are needed to assess these relationships. In addition, elements critical to their well being — such as flows, habitat, water quality, and other physical and biologi- cal requirements — need to be determined. This information has utility in deter- mining impacts on suckers caused by man. SUMMARY 1. Spawning population consisted of fish aged 4-12, with a majority of the spawners aged 5-7. 2. Female suckers were generally longer-lived and usually larger. 3. Adult suckers first entered Thomes Creek in December and peaked in num- bers during March. 4. Ripeness level was highest during early March through late April. 5. Sex ratio of the spawning migration was 2.17 males to every female. 6. Sacramento suckers matured sexually at age 4 but most commonly at ages 5 and 6. SACRAMENTO SUCKER LIFE HISTORY 105 7. Fecundity ranged from 9,687 to 32,335 eggs/female with an average of 16,358 for 50 adult females (Sfl = 429 mm). 8. Sacramento suckers spawned in groups and broadcasted adhesive eggs. 9. Hatching time for Sacramento suckers was 4 to 5 wk. 10. Larval suckers were first observed in late April. 1 1 . Emigration of juvenile and larval suckers was continuous when water flowed at the mouth. Most larval emigration occurred during May and June. 12. Sacramento suckers exhibited a curvilinear length and weight relationship: Log 10 = 4.9246 + 2.9246 Log ,o L (r = .99). 13. Sacramento suckers mainly ate algae and detritus while insects appeared to be consumed incidentally. ACKNOWLEDGMENTS The following seasonal aids were instrumental in conducting the field work and data reduction: V. McGowan, R. Beane, A. Schenk, S. Valdez, D. Miles, and R. Brown. Without their diligence and dedication, this report would not have been possible. C. Brown and L. Puckett provided support and ideas throughout the study. H. Chadwick, P. Moyle, K. Hashagen, B. Vondracek, J. Monroe, and C. Brown critically reviewed the manuscript. C. Maxwell drew the figures and D. McGill, H. Chew, J. Daniels, V. Vandeburgh, S. Lewis, and A. Cox typed the numerous drafts. This study was conducted as part of an environmental assessment of impacts of the proposed Thomes-Newville Unit of the State Water Project, Work Author- ity 1610-3080. LITERATURE CITED Ashley, P. 1974. The summer feeding ecology of the Humboldt sucker, Catostomus humboldtianus, and juvenile steelhead, Salmo gairdneri gairdnerl, in the upper Eel River system. Thesis, Humboldt State Univ., 76 pp. Bailey, M. M. 1969. Age, growth, and maturity of the longnose sucker, Catostomus catostomus (Forster) of Western Lake Superior. Fish. Res. Bd. Can., J. 26(3): 633-638. Borgeson, D. P. 1966. A rapid method for food habits studies. Amer. Fish. Soc, Trans. 92(4): 434—435. Branson, B. A. 1961. Observations on the distribution of nuptial tubercles in some catostomid fishes. Kansas Acad. Sci., Trans., Vol. 64, No. 4, 360-372. Brauer, C. 1971. A study of the western sucker, Catostomus occidentalls Ayres, in lower Hat Creek, California. Thesis, Humboldt State Univ., 41 pp. Brown, C. J. D., and R. ). Graham. 1954. Observations on the longnose sucker in Yellowstone Lake. Amer. Fish. Soc, Trans., 83: 38-46. Brown, L. A. 1980. Thomes-Newville and Glenn Reservoir plans, engineering feasibility. Calif. Dept. of Water Resources, Northern District Report, 191 pp. Apendices. Burns, ). W. 1966a. Western sucker. Pages 516-517 in A. Calhoun ed. Inland Fisheries Management. Calif. Dept. Fish and Game. 1966fo. Sacramento squawfish. Pages 525-527 in A. Calhoun ed. Inland Fisheries Management. Calif. Dept. Fish and Game. Campbell, R. S. 1935. A study of the common sucker, Catostomus commersonll (Lacepede), of Waskesiu Lake. Thesis, Univ. Sask., 48 pp. Carlander, K. D. 1969. Handbook of Freshwater Fishery Biology. Vol. 1. Iowa State Univ. Press, Ames, Iowa, 752 PP Davis, S. P. 1963. Commercial freshwater fisheries of California. Calif. Fish Game, 49(2): 84-94. Dill, W. A. and |. H. Wales. 1945. The fishery of Shasta Lake, Shasta County. Report No. 1, Inland Fish. Admin. Rept. 45-8, 149 pp. Eddy, S., and K. D. Carlander. 1940. The effect of environmental factors upon the growth rates of Minnesota fishes. Minn. Acad. Sci., Proc, 8: 14-19. Elsey, C. A. 1946. An ecological study of the competitor fish in Pyramid Lake, Jaspar, with special reference to the northern sucker. Thesis, Univ. Sask., 61 pp. 106 CALIFORNIA FISH AND CAME Fowler, H. W. 1913. Notes on catostomid fishes. Acad. Nat. Sci. Phila., Proc, 65: 45-71. Geen, C. H., T. C. Northcote, C. F. FHartman, and C. C. Lindsey. 1966. Life histories of two species of catostomid fishes in Sixteenmile Lake, British Columbia, with particular reference to inlet stream spawning. Fish. Res. Bd. Can., J. 23(11): 1761-1788. Harris, R. H. D. 1952. A study of the sturgeon sucker in Great Slave Lake, 1950-51. Thesis, Univ. Alta., 44 p. 1 962. Growth and reproduction of the longnose sucker, Catostomus catostomus ( Forster) , in Great Slave Lake. Fish. Res. Bd. Con., J. 19: 113-126 Hauser, W. J. 1969. Life history of the mountain sucker, Catostomus platyrhynchus in Montana Am. Fish. Soc. Trans. 98(2): 209-224. Hayes, M. L. 1956. Life history studies of two species of suckers in Shadow Mountain Reservoir, Grand County, Colorado. Thesis, Colo. A. M. Coll. 126 pp. Hopkirk, J. D. 1973. Endemism in Fishes of the Clear Lake Region. Univ. Calif. Pub. ZooL, 96: 160. Hubbs, C. L., and O. L. Wallis. 1948. The native fish fauna of Yosemite National Park and its preservation. Yosemite Nat. Notes, 27(12): 131-144. Kimsey, J. B., and L. O. Fisk. 1964. Freshwater Nongame Fishes of California. Calif. Dept. Fish and Game, 54 pp. Lagler, K. F. 1959. Freshwater Fishery Biology. Second ed., Wm. C. Brown Co., Dubuque, Iowa, 421 pp. Macphee, C. 1960. Postlarval development and diet of the largescale sucker, Catostomus macrocheilus (Girard) in Idaho. Copeia, 1960, (2): 119-125. McCrimmon, H. R., and A. H. Berst. 1961. The native fish population and trout harvests in an Ontario farm pond. Prog. Fish. Cult., 23(3): 106-13. Moyle, P. B. 1976. Inland Fishes of California. Univ. Calif. Press, 405 pp. and R. Nichols. 1973. Ecology of some native and introduced fishes of the Sierra-Nevada foothills in central California. Copeia, 1973(3): 478-^90. and . 1974. Decline of the native fish fauna of the Sierra-Nevada foothills, central California. Amer. Midland Nat., 92(1): 72-83. Moyle, P. B., B. Vondracek, and G. D. Grossman. 1983. Responses to fish populations in the North Fork of the Feather River, California, to treatments with fish toxicants. N. Amer. J. Fish. Mgt. 3(1): 48-60. Ovchynnyk, M. M. 1965. On age determination with scales and bones of the white sucker, Catostomus commer- soni (Larcepede). Zool. Anz., 175: 325-345. Raney, E. C, and D. A. Webster. 1942. The spring migration of the common white sucker, Catostomus c. commersonii (Lacepede), in Skaneateles Lake Inlet, New York. Copeia, 1942(3): 139^8. Ricker, W. E. 1975. Computation and interpretation of biological statistics of fish populations. J. Fish. Res. Bd. Can. Bull. 191, 382 pp. Rutter, C. 1908. The fishes of the Sacramento-San )oaquin basin, with a study of their distribution and variation. Bull. U. S. Bur. Fish. 27(637): 103-152. Seber, G. A. F.l 1973. The Estimation of Animal Abundance and Related Parameters. Charles Griffin and Co., Ltd., London. 506 pp. and E. D. LeCren. 1967. Estimating population parameters from catches large relative to the population. J. Anim. EcoL, 36(3): 631-643. Skinner,]. E. ^95G. White sturgeon, Acipenser transmontanus (Richardson), with special reference to the life history and ecology of the California population. Data for Handbook of Biological Data, 2 pp. Snedecor, C. W., and W. G. Cochran. 1967. Statistical Methods. Iowa State Univ. Press, Ames, Iowa. 593 pp. Snyder, J. O. 1905. Notes on the fishes of the streams flowing into San Francisco Bay. Rept. Bur. Fish. App. 5: 327-338. Spoor, W. A. 1939. Age and growth of the sucker, Catostomus commersonii (Lacepede), in Muskellunge Lake, Vilas County, Wisconsin. Wis. Acad. Sci. Arts Lett., Trans. 31: 457-505. Willsrud, T. 1971 . A study of the Tahoe sucker, Catostomus tahoensis (Gill and Jordan) . Thesis, San Jose State Coll., 96 pp. NOTES 107 Calif. Fish and Came 7 1 ( 2 ): 1 07-1 28 1 985 NOTES GROWTH OF GRASS CARP, CTENOPHARYNGODON IDELLA, IN ARTIFICIAL CENTRAL ARIZONA PONDS Grass carp, Ctenopharyngodon idella, is a western Asian cyprinid transplanted widely throughout the world, primarily for control of nuisance aquatic vegeta- tion (Cross 1969). It was introduced to the United States in 1963 (Stevenson 1965), and now is known from at least 34 states (Guillory 1980). The species was first stocked into Arizona waters in 1965 (Marsh and Minckley 1983a). Because of its potential for aquatic vegetation control, growth and feeding dynamics of grass carp have received considerable attention (Venkatesh and Shetty 1978; Shelton, Smitherman, and Jensen 1981; Shireman and Maceina 1 981 ) . We are unaware of studies of North American populations that document annual growth in length beyond the second year, nor of any successful efforts to determine growth history from scale analysis. Pflieger (1978) aged 18 fish between ages II and V (?) from the Missouri River, but could not back-calculate lengths due to lack of accurate specimen data. We report annual growth as determined from examination of scales of grass carp in central Arizona. METHODS Grass carp were stocked in 1970 or 1971 (exact date unavailable) into seven small, artificial ponds at Sun Lakes, central Arizona. Specifications of ponds and their fish communities were reported by Marsh and Minckley (19836). Size of fish at introduction reportedly was 152-203 mm. Ponds were reclaimed in April 1978 with rotenone. Grass carp were measured (tl, mm) and weighed (nearest 0.01 kg). Scales were removed from the left side ventral to the dorsal fin, cleaned, dried, mounted between glass slides, and examined independently by each of us at 15x on a Bausch & Lomb Tri-Simplex microprojector. The magni- fied total scale radius from focus to anterior margin and the anterior distance from focus to each annulus were measured (nearest mm). Regenerated scales were discarded. Fish lengths at consecutive annuli were back calculated by the formula L' = S'/S (L) where L' is tl at annulus formation, L is tl at capture, S' is annular radius, and S is total scale radius. Least squares linear regression of S on L to obtain an intercept value "c" (approximation of tl at scale formation) gave a "nonsense" value because available data for L and S did not include a range sufficient to calculate a reliable expression. Therefore, no adjustment to the equation was made. RESULTS AND DISCUSSION Scales suitable for analysis were obtained from 91 of 190 grass carp in six ponds. No samples were obtained from an additional 43 specimens in the seventh pond. At capture, fish were 630-1025 mm tl and 2.80-16.13 kg (x = 739 ± 106 mm, 6.5 ± 2.4 kg.). The high proportion of regenerated scales was likely due to scale loss or damage in the hatchery and during handling or 108 CALIFORNIA FISH AND GAME transport. All scales had seven clear annuli. Tissue accumulated beyond the last annulus indicated growth resumption and annulus formation were about to occur at capture. Annual growth was consistent among ponds, relatively slow during the first two years (81 and 48 mm), increasing dramatically during year 3 (259 mm), and decreasing thereafter (Table 1 ) . Assuming annulus formation in spring, fish were spawned in 1970 and stocked in late (winter) 1971 or early (spring) 1972, prior to second annulus formation. Hatchery growth was poor due to density depend- ent (Shelton et al. 1981 ) or other factors, a pattern also observed in hatchery fish later collected in the Missouri River (Pflieger 1978). Second annulus forma- tion occurred after stocking. Third year growth was rapid as habitat provided ample space and food. An apparent reduction in annual increment the second year after stocking (fourth year of growth) may reflect reduction in aquatic vegetation, which reportedly was decimated by the grass carp. Many authors have failed to report or did not know age or lengths of captured grass carp. Few comparable growth data are thus available. Our fish averaged 81 mm at the first annulus. Grass carp attained mean total lengths of 280 mm in a year in Arkansas (Stevenson 1965), and Hora and Pillay (1962) reported lengths of 150 to 300 and 600 mm after one and two years, respectively, in the South Pacific. These rates are considerably greater than ours, which is attributed to slow hatchery growth. Shelton et al. (1981 ) determined first year lengths of 50 to 75 and 175 to 200 mm for grass carp in ponds at densities of 470,000 and 14,000/ha, respectively. Nikol'skii (1954) reported annual growth of grass carp, presumably in nature, as follows: I {77 mm), II (156 mm), III (223 mm), IV (289 mm), V (360 mm), VI (422 mm), and VII (480 mm), lengths similar to those of our fish during the two hatchery years, but considerably less than in subse- quent (Arizona) years. Mean length, weight, and standing crop (kg/ha) of grass carp were similar in five ponds, but all were significantly greater in a sixth (t-test, p < 0.05). There appeared a relationship among these parameters, sequential position of ponds within the interconnected system, water quality, and nature of inputs, as pos- tulated by Marsh and Minckley (19836). However, lack of data prevent further quantification except for a linear increase in mean size of fish with increasing standing stock. ACKNOWLEDGMENTS Fish were collected by Arizona State University fishery management students under direction of Arizona Game and Fish Department. W. L. Minckley re- viewed and edited the manuscript. LITERATURE CITED Cross, D. C. 1969. Aquatic weed control using grass carp. ). Fish Biol., 1 ; 27-30. Cuillory, V. 1980. Ctenopharyngodon idella Valenciennes, Crass Carp. P. 151, in: D. S. Lee, et al., eds. Atlas of North American Freshwater Fishes. N.C. State Mus. Nat. Hist. Raleigh, N.C. X + 854 p. Hora, S. L. and T. V. R. Pillay. 1962. Handbook of Fish Culture in the Indo-Pacific region. FAO, UN, Rome, 204 P- Marsh, P. C. and W. L. Minckley. 1983a. Escape of hybrid grass x bighead carp into central Arizona. N. Amer. J. Fish. Manag., 3:216-217. Marsh, P. C. and W. L. Minckley. 19836. Recovery of grass carp, channel catfish, and centrarchids in artificial central Arizona ponds. AZ-NV Acad. Sci., J., 18:47-51. Nikol'skii, G. v. 1954. Special Ichthyology. Transl. from Russian, Israel Prog. Sci. Transl. Jerusalem (1961 ). 538 p. NOTES 109 (75 E o U (A o o 3 C C < V ^> 3 U e o u 3 u I w ea ■o c O c J a (/) < +1 Si 2 N, ^ *\I f^ ^ 0 +1 u 01 . !r. o c S N c Q.V1 a-~ ? fS^ k ^ O +1 § n) — f^ E 2 d Bio Cent 1 ^1 Ss ^ O ^ -^ ^ -J E c ^^ 3 3 Z U-) LO ro rsi rsi « — + 1 +1 +1 +1 +1 +1 +1 T <— -^ CO M- 'S- -^ l\ O r^ LA in o^ o O r\ CO o vD Ln r^ (Ti i-n oo -^ O t~~. ■^ u^ '^ LT) IT) rr\ r-4 O^ +1 +1 +1 +1 +1 +1 +1 1 — in ^ 1 — Lo LA o O Ln o ' — r^ r^ Lo O O CO "^D vD LO ^ O r^ u-i m m CO ^ tn r^ vX) Ln ^ »— a^ + 1 +1 +1 +1 +1 +1 +1 'T CO CT^ r^ O u-> Tj- ' — r\ 1 — LT) vx> »— r\ LTi Lo r^ Ln Ln Ln LT) a^ '»^ o r\ -^ vX) r— ■^ o^ ^^ ^ri m »— ffs + 1 +1 +1 +1 +1 +1 +1 r-^ Ln oo ^ ^r> ^ ro ro O^ rs| O r\ LT) O^ tT TT O ■*■*■* -^l- 1^ CO i\ CO O O ■"' o tn +1 !j^ +1 +1 +1 +1 +1 T P" O Ln f>^ r^ CO ro V:; LTi m "^ - - ro 'T >— CM t-^ LO hv .— cs CM r~^ I— <— .— rsi +1 +1 +1 +1 +1 +1 +1 tT^ CO O^ ro <— O CTs rvi rsi ro rs) rsi m Osi 5 a^ rn o> -^ r\ T— hx 00 r^ f^ CO CO o >— "> o ^ "■ LO LTi -"T 'T O O O rs) +1 +1 +' +1 +1 +1 +1 >— ; 0^ ^ CO O rv. iri •^ ■^" ^ ro ro r~i v£) O t\ ^ ro 0^ LT) O ■^ ■^ ■^ l-O <— t-M .— +1 +1 +1 +1 +1 +1 +1 O oo * — CO o o o^ T— .— ro OO op r-4 m t^^ r^ o^ O ^ O ("^ Pj =^ CO ^:::^5^ CJ^ O ro -^ ,„ CO CO CO CO rs bK O rsi rn in rsi "^ »— 1 — t\ ro CT^ vTJ O h^ v^ LH in rsi ^ CO 0^ CO O •'T eo vX> CO >— OO CM T— I— r- .— O.) .— +1 +1 +1 +1 +1 +1 +1 J5 E i-n'0.05). Regression slopes for bluegill orientation, —0.25 and —0.27 in light and dark tests, were not significantly different (P>0.05). These results indicate that the detection and orientation response of chinook salmon and bluegill was inde- pendent of light intensity. Furthermore diferences in regression slopes were not 112 CALIFORNIA FISH AND CAME significant (P>0.05) between salmon and bluegill in light and dark tests, al- though the two species have very different habitat preferences. Blinded fish have been used by several other investigators in studies of locomotor behavior and orientation. Although this approach assures the ab- sence of a visual response, we observed high mortality ( > 50%) in fish blinded by surgical removal of both eyeballs. With these levels of mortality and accom- panying physiological stress, we chose to use unaltered fish tested under natural nighttime light intensities. By using infrared photographic techniques, the fish were tested under conditions typical of natural light levels encountered in shal- low streams and lakes on clear, moonless nights. Although our studies do not (/) ■o o c o c 0) so 3 c < 2.0- 1.8- 1.6 1.4- 1.2- 1.0- .8 - .6 - .4 - .2 - Velocity (crry'sec) FICURE 1. Least-squares linear regression of orientation against water velocity: (A) hypothetical line of no response; (B) chinook salmon high light; (C) bluegill low light; (D) bluegill high light; (E) chinook low light. NOTES 113 represent the orientation response of fish in the complete absence of possible visual response, they do reflect conditions encountered under natural diel light regimes. The ability of juvenile chinook salmon and bluegill to detect and respond to low velocity water currents independently of light intensity suggests that for these species visual cues do not play a significant role in orientation to water currents. Results of this study provide no evidence that the nocturnal seaward migration observed for juvenile salmonids is the result of a loss of the ability to detect and respond to water currents at night. ACKNOWLEDGMENTS This work was supported in part by funds provided by the United States Department of the Interior as authorized under the Water Resources Research Act of 1964 as amended, j. Skinner (deceased), D. Odenweller, and other members of the California Department of Fish and Game contributed greatly to the study. Facilities and equipment were provided by the University of California at Davis, Department of Wildlife and Fisheries Biology. L. Decker, j. White, E. Wong, J. Stiles, and S. Hanson provided technical assistance. H. Li and j. Cech reviewed the manuscript. TERA Corporation assisted in the preparation of the manuscript. LITERATURE CITED Hoar, W.S. 1951. The behavior of chum, pink, and coho salnnon in relation to their seaward migration. Can., Fish. Res. Bd., )., 8: 241-263. — Charles H. Hanson, TERA Corporation, 2150 Shattuck Avenue, Berkeley, CA 94704, and Erik Jacobson, California Public Utilities Commission, 350 McAllis- ter Street, San Francisco, CA 94102. Accepted April 1984. RADIO-TAGGED HARBOR SEAL, PHOCA VITUUNA RICHARDS!, EATEN BY WHITE SHARK, CARCHARODON CARCHARIAS, IN THE SOUTHERN CALIFORNIA BIGHT On 22 July 1983 a commercial fishing vessel caught a male white shark, Carcharodon carcharias, in a gill net approximately 16 km south of Anacapa Island, California (lat. 34°00'N., long. 119°25'W). Sea World, Inc., San Diego, obtained the shark and packed it in ice until it was necropsied on 26 July. The shark weighed 948 kg and measured 4.7 m in total length (4.3 m fork length). The shark's stomach contained the remains of a juvenile elephant seal, Mi- rounga angustirostris, an adult harbor seal, Phoca vitulina richardsi [Shaughnessy and Fay (1977) discuss the spelling of the subspecific name of this taxon], a radio-transmitter, and a red Dalton Roto tag. The seals were apparently con- sumed in large pieces. The head of each was severed cleanly from the torso through the neck, the harbor seal at the third cervical vertebra and the elephant seal behind the occipital condyles. The heads and other tissues were in very early stages of digestion and were likely consumed within several days of the shark's capture. The quantity of tissue and bones in the shark's stomach indicates that most, if not all, of each seal was eaten. The radio-transmitter (still functioning when tested on 6 August) and the Roto tag had been attached by us to the rear ankle and flipper of an adult female harbor seal (standard length — 1.48 m, girth— 1.11 m) at San Nicolas Island (lat. 114 CALIFORNIA FISH AND GAME 33°15'N, long. 119°30'W) on 23 May 1983. The seal had been hauled out on 18 of 31 days from 6 June through 6 July for an average of 8.0 h per day. If the seal had been hauled out at San Nicolas Island between 7 July and 22 July, the event (s) would have been recorded by one of our Esterline Angus (20 channel, scanning, D.C. powered) recording stations which operated continuously fronn late March 1983 through August 1983. The seal therefore apparently departed San Nicolas Island on 6 July. Our prelinninary studies of post-breeding and molting season movements of harbor seals in the Southern California Bight suggest that some seals may be pelagic or somewhat migratory in autumn and winter (Stewart 1981, Stewart and Yochem, unpubl. data). We suspect that the radio-tagged seal departed San Nicolas Island after completing the molt in early July and was consumed between 18 and 20 July near the northern Channel Islands. Evidence for shark predation on pinnipeds consists primarily of observations of shark-like scars and fresh wounds on seals and sea lions, and of remains of harbor seals (Bonham 1942; Fitch 1949; McCosker 1981; LeBoeuf, Riedman and Keys 1982), sea lions (Jordan and Evermann 1896, Walford 1935, Scholl 1983) and elephant seals (McCosker 1981, LeBoeuf et al. 1982) found in sharks' stomachs. Recently, Ainley et al. (1981 ) and Ainley et al. (In press) reported 90 inde- pendent observations of pinnipeds at the Farallon Islands being attacked and consumed by white sharks from 1970 through 1982. LeBoeuf et al. (1982) reported that the stomachs of seven white sharks caught or washed ashore in central and southern California (1975-1978) contained either harbor seal or elephant seal remains. Elephant seals apparently are consumed more frequently by white sharks than are other pinnipeds that occur off California (Ainley et al. 1981, LeBoeuf et al. 1982, Ainley et al. In press). Attacks by white sharks on pinnipeds (Ainley era/. 1981, LeBoeuf ef a/. 1982, Ainley et al. In press), sea otters (Ames and Morejohn 1980), and humans (Miller and Collier 1981, Lea and Miller 1983) in coastal California waters have increased in recent years. In northern and central California the increase in number of shark attacks, and possibly in white sharks (Miller and Collier 1981 ) may be related to an increase in marine mammal populations (Ainley e? a/. 1981, LeBoeuf et al. 1 982 ) . Populations of northern elephant seals, California sea lions, Zaiophus californianus, northern fur seals, Callorhinus ursinus, and harbor seals have increased significantly during the past fifty years on the Southern California Channel Islands (LeBoeuf and Bonnell 1980; DeLong 1982; DeMasteref a/. 1982; Cooper and Stewart 1983; Stewart and Yochem 1984). No data are available on the status or growth of the white shark population in the Southern California Bight. From 1979 through 1983 we have observed 48 elephant seals, 11 harbor seals and eight California sea lions at San Nicolas and San Miguel Islands that bore fresh wounds or scars probably inflicted by white sharks. These pinnipeds are seasonally migratory and it is possible that some were attacked north of Point Conception, where white shark attacks have been most obvious (e.g., Ames and Morejohn 1980, Ainley et al. 1981, Miller and Collier 1981). Ainley et al. (1981) suggested that "white shark predation is probably an important natural control on pinniped population size." Inasmuch as the pinniped populations in California and Baja California waters are rapidly increas- ing we see no evidence that shark predation is now an important check to population growth at most rookeries. NOTES 115 ACKNOWLEDGMENTS We thank R. Keyes, B. j. LeBoeuf, G. A. Antonelis, R. L. DeLong, J. R. |ehl, Jr., D. G. Ainley, and an anonymous reviewer for commenting on the manuscript. We also thank the Sea World, San Diego, Aquarium Department for their help. Advanced Telemetry Systems, Inc., Bethel, Minnesota, manufactured the radio- transmitter. LITERATURE GITED Ainlev, D, C, C. S. Strong, H. R. Huber, T. |. Lewis, and S. H. Morrell. 1981. Predation by sharks on pinnipeds at the Farallon Islands. U.S. Fish. Bull. 78: 941-945. Ainley, D C, R. P. Henderson, R. I. Boekelheide, H. R. Huber, and T, L. McElroy. In press. White shark-pinniped interactions at the Farallon Islands. Proc. Calif. Acad. Sci. Ames, |. A., and C. V. Morejohn. 1980. Evidence of white shark, Carcharodon carcharias, attacks on sea otters, Enhydra lutris. Calif. Fish Game, 66(4): 196-209. Bonham, K. 1942. Records of three sharks on the Washington coast. Copeia, 1942:264-266. Cooper, C. F., and B. S. Stewart. 1983. Demography of northern elephant seals, 1911-1982. Science, 219:969-971. DeLong, R. L. 1982. Population biology of northern fur seals at San Miguel Island, California. Dissert., Univ. California Berkeley, 203 p. DeMaster, D. P., D. ). Miller, D. Goodman, R. L. DeLong and B. S. Stewart. 1982. Assessment of California sea lion — fishery interactions. Trans. 47th N. Am. Wildl. Nat. Res. Conf. p. 253-264. Fitch, J. E. 1949. The great white shark, Carcharodon carcharias, in California waters during 1948. Calif. Fish Game, 35(2):135-138. Jordan, D. S., and B. W. Evermann. 1896. The fishes of north and middle America. Bull. U.S. Nat. Mus., 47 (Pf.l):l-954. Lea, R. N., and D. J. Miller. 1983. Shark attacks off the California and Oregon coast: an update. Abstract No. 66. Annu. Meeting So. Calif. Acad. Sci., May 6-7, 1983, Calif. State Univ., Fullerton. LeBoeuf, B. J., and M. Bonnell. 1980. Pinnipeds of the California islands: abundance and distribution. Pages 475^83 in D. Power, ed. The California Islands: Proceedings of a Multi-Disciplinary Symposium. Santa Barbara Museum of Natural History, Santa Barbara, Calif., 787 p. LeBoeuf, B. )., M. Riedman, and R. S. Keyes. 1982. White shark predation on pinnipeds in California coastal waters. Fish. Bull., 80:891-895. McCosker, J. E. 1981. Great White Shark. Science 81, 2:42-51. Miller, D. |., and R. S. Collier. 1981. Shark attacks in California and Oregon, 1926-1979. Calif. Fish Game, 67(2);76-104. Scholl, |. P. 1983. Skull fragments of the California sea lion (Zaiophus caiifornianus) in stomach of a white shark [Carcharodon carcharias) J. Mamm., 64:332. Shaughnessy, P. D., and F. H. Fay. 1977. A review of the taxonomy and nomenclature of North Pacific Harbour seals. J. Zoo!., Lond. 182:385-419. Stewart, B. S. 1981. Seasonal abundance, distribution, and ecology of the harbor seal (Phoca ^itulina richardsi) on San Miguel Island, California. Thesis., San Diego State Univ., San Diego, Calif., 66 p. Stewart, B. S. and P. K. Yochem. 1984. Seasonal abundance of pinnipeds at San Nicolas Island, California, 1980-1982. Bull. So. Calif. Acad. Sci. 83:121-132. Walford, L. A. 1935. The sharks and rays of California. Calif. Div. Fish and Game, Fish Bull., (45)1-66. — Brent S. Stewart and Pamela K. Yochem. Hubbs-Sea World Research Institute, 1700 South Shores Road, San Diego, California, 92109. Accepted for publica- tion June 1984. 116 CALIFORNIA FISH AND CAME ADDITIONAL RECORDS OF PROMOTOGRAMMUS MUL Tl FASCIA TUS AND GEMPYL US SERPENS FROM CALIFORNIA In the winter'; of 1979 and 1981 two threadfin bass, Pronotogrammus multifas- ciatus (Family Serranidae), were collected oft southern California. P. multifas- ciatus Gill, a senior synonym of Anthias gordensis Wade (Fitch 1982), is known from only two California records. Hobson (1975) reported the first California specimen. Fitch (1982) reported P. multifasciatus to range as far north as Por- tuguese Bend, Los Angeles County, California. While Fitch did not list materials examined, it is believed the Portuguese Bend specimen refers to the P. multifas- ciatus (CMM 81.22.2) discussed below. In the spring of 1981 a snake mackerel, Gempylus serpens (Family Gempylidae), was collected from southern Califor- nia. The snake mackerel has been reported from California only once. Both species normally have more southern distributions. A threadfin bass was trawled from a depth of 72-80 m by Freire Lopez on 19 February 1979. This 110 mm SL specimen was collected by a squid trawler off the California coastline between lat 33°15'-16' N and long 117°31'-34' W; the trawl hit bottom during the tow. The specimen was identified by Richard H. Rosenblatt and deposited at Scripps Institution of Oceanography (this specimen was not examined by us). Another threadfin bass was caught by joe Crozer on 18 January 1981 in 80 m off Pt. Fermin (lat 33° 42' N, long 118° 20' W). This specimen measured 182 mm SL and fits the diagnosis given by Fitch ( 1 982 ) . Color notes were taken soon after death. Dorsal and lateral trunk brilliant red with dark vertical crosshatching. Chin, ventral trunk, caudal peduncle and fin yellow. Head red with dark spotting. Gold stripes radiate from eye to posterior margin of operculum. Color in alcohol tan with pale yellow venter. Eye stripes faint. Gut contents were almost entirely copepods as was noted for the first California specimen (Hobson 1975). It is interesting to note, however, that this specimen was caught on rod-and-reel using an anchovy for bait and was brought to the surface along with "rockcod" iSebastes spp.). The specimen is deposited in the Cabrillo Marine Museum, CMM 81.22.2. A second California specimen of the snake mackerel was collected at the junction of Cabrillo Beach and the tidepools off Pt. Fermin (lat 33° 42' N, long 118° 17' W) by Dennis Crupi and Elizabeth Kelly on 8 March 1981 as it floun- dered in the surf. The 532 mm SL, 193 g, specimen was easily identified by the long snake-like body, two lateral lines joined anteriorly, and numerous posterior finlets (Fitch and Lavenberg 1968). The specimen is deposited in the Cabrillo Marine Museum, CMM 81.22.1. The first record of C serpens for California was reported by Fitch and Lavenberg (1968). John E. Fitch supplied us with addition- al information on the fish, LACM 9608-1; the specimen measured 515 mm sl, 535 mm tl, and weighed 170 g. It was collected by Bill Schaefer in a tidepool at Whites Pt., Los Angeles County, on 13 February 1967, as it too swam feebly in shallow water. There is some evidence that the northward occurrence of these fishes may be correlated to warmer than usual water temperatures. This phenomenon has been documented several times for the California coastlines ( Hubbs and Schultz NOTES 1 1 7 1929, Walford 1931, Hubbs 1948, Radovich 1961). Mearns (1980) noted that a warm, clear, winter water trend spanned the 1976-80 time period (Mearns, pers. commun., gave us additional temperature data for the April 1980-April 81 period). While these data indicate that 1980 was not a warm water year overall, the fall and winter months of 1980-81 appeared warmer than usual. It should be noted that while C. serpens has a normal vertical distribution from the surface to at least 1000 m (Miller and Lea 1976), P. multifasciatus tends to stay in cool subsurface waters from 40-205 m (Fitch 1982). ACKNOWLEDGMENTS We would like to thank R. J. Lavenberg, Los Angeles County Museum of Natural History; the late J. E. Fitch, California Department of Fish and Came; R. Bray, California State University, Long Beach; and A. J. Mearns, Southern Califor- nia Coastal Water Research Program. R. H. Rosenblatt, Scripps Institution of Oceanography, supplied data on P. multifasciatus. We gratefully acknowledge the initial efforts of the collectors. B. Wheeler of Seal Beach donated the P multifasciatus, CMM 81.22.2. J. Olguin and S. Lawrence-Miller, associate directors of the Cabrillo Marine Museum graciously allowed the use of the museum facilities. R. Fritzsche, hlumboldt State University, and the late J. E. Fitch critically re- viewed an earlier version of the manuscript. LITERATURE CITED Fitch, J. E. 1982 Revision of the eastern North Pacific anthiin basses (Pisces: Serranidae). Contrib. Sci. (Nat. Hist. Mus. Los Angeles Co.). No. 339:1-8. Fitch, J. E. and R. J. Lavenberg. 1968. Deep-water teleostean fishes of California. Univ. of Calif. Press. 155p. Hobson, E. S. 1975. First California record of the serranid fish Anthlas gordensis Wade. Calif. Fish Game, 61 (2): 111-112. Hubbs, C. L. 1948. Changes in the fish fauna of western North America correlated with changes in ocean temperature. Sears Found. Journ. Mar. Res. 7(3):459^82. Hubbs, C. L. and L. P. Schultz. 1929. The northward occurrence of southern forms along the Pacific coast in 1926. Calif. Fish Came, 15(3):234-241. Mearns, A. |. 1980. Changing coastal conditions: 1979 compared to the past 25 years. Coastal Water Research Project. Biennial Report 1979-1980:273-284. Miller, D. J. and R. N. Lea. 1976. Guide to the coastal marine fishes of California (revised edition). Calif. Dept. Fish and Game, Fish Bull., (157):l-249. Radovich, J. 1 961 . Relationships of some marine organisms of the northeast Pacific to water temperature, particular- ly during 1957 through 1959. Calif. Dept. Fish and Game, Fish Bull., (112):1-62. Walford, L. A. 1931. Northward occurrence of southern fish off San Pedro in 1931. Calif. Fish Game, 17(4):401^05. — Lawrence L. C. Jones, California State University, Long Beach, California 90840; Robert R. Johnson and Judith Hopkins, Cabrillo Marine Museum, 97720 Stephen M. White Drive, San Pedro, California 90731. Accepted for Publica- tion February 1984 PUGHEADEDNESS IN THE CALIFORNIA ROACH HESPEROLEUCUS SYMMETRICUS (BAIRD AND GIRARD) The morphological anomaly known as pugheadedness has been described in at least 14 different families of fish (Table 1). Pugheadedness may be character- ized in part, as an abnormal elevation and protrusion of the median portion of the cranium. However, the form and extent of pugheadedness may vary consid- erably within and between species. Descriptions of skull deformities attributed to pugheadedness in various fishes are presented in Gudger ( 1 930) and Dawson (1964, 1966). 118 CALIFORNIA FISH AND CAME TABLE 1. Published Records of Pugheadedness in Various Families of Fish REFERENCE SPECIES Clupeidae American shad, Alosa sapidissima Menhaden, Brevoortia tyrannus Salmonidae Rainbow trout, Salmo gairdnerii Brown trout, Salmo trutta Kundzha, Salvelinus leucomaenis Esocidae Northern pike, Esox lucius Cyprinidae Common carp, Cyprinus carpio Verkhovka, Leucaspius delineatus Percichthyidae Striped bass, Morone saxatilis White bass, Roccus chrysops Centrarchidae Largemouth bass, Micropterus salmoides Percidae Yellow perch, Perca flavescens Percid, Stizostedion sp. Pomatomidae Bluefish, Pomatomus saltatrlx Lutjanidae Vermilion snapper, Rhomboplites aurorubens Sciaenidae Silver perch, Bairdiella chrysura Spotted seatrout, Cynoscion nebulosus Labridae Tautog, Tautoga onitis Zaniolepididae, Zaniolepis latipinnis Aphredoderidae Pirate perch, Aphredoderus sayanus Cadidae Cod, Gadus sp. Cheek 1965 Schwartz 1965 Croker 1931 Forsyth 1926, Gudger 1929 Honma and Yoshie 1978 Lawler 1966 Rondelet 1555 Knauthe 1893a, 18936 Ayres 1849; Sutton 1913; Mansuetti 1958, 1960; Alperin 1965; Smith 1967; Grinstead 1971 Panceri 1872; Mazza 1893; Fasciolo 1904 Herrick 1885 Cheek 1965, Lawler 1966 Pellegrin 1908 Hickey and Austin 1974 Bortone 1971 Gudger 1930 Rose and Harris 1968 Briggs 1966 Talent 1975 Bortone 1971 Cheek 1965 Two pugheaded California roach, Hesperoleucus symmetricus, were record- ed from streams in separate drainages as part of collections made during a larger zoogeographic study of stream fishes of the San Francisco Bay drainage basin (Leidy, 1984). Although this deformity has been recorded in two other cyprinid species, these specimens represent the first published record of pugheadedness in the California roach. On 23 July 1981, a single specimen was collected rom San Lorenzo Creek, a small, intermittent, urbanized stream tributary to S- i Francisco Bay, California (Figure 1). This specimen measured 59 mm fork length (fl) and was taken in a sample of 162 juvenile and adult California roach, ranging from 51 to 101 mm FL. This pugheaded specimen exhibited an elevation of the cranium in the orbital region with what appears to be an oblique elongation of the orbits (Figure 2.) The forehead is steep and there is a protrusion of the mandibles, although the lower jaw is lacking slightly. No exophthalmia was noted. NOTES 119 SACRAMENTO PACIFIC OCEAN FIGURE 1. Map showing the locations of streams where pugheaded Hesperoleucus symmetricus were collected. On 10 October 1981, a second pugheaded California roach was collected from Del Puerto Creek, an intermittent tributary of the San Joaquin River system, draining the dry, eastern slope of the Inner Coast Ranges (Figure 1 ). This speci- men measured 67 mm fl and was collected in a sample of 10 juvenile and adult California roach, ranging from 37 to 80 mm fl (Figure 3). As was evident in the other pugheaded specimen, the cranium in the region of the eyes had been elevated. The orbit exhibited a slightly enlarged diameter, but no exophthalmia was evident. In contrast to the San Lorenzo Creek roach, this specimen exhibited a blunted snout and protruding lower mandible (Figure 4). The angle created by the intersection of the line of the flattened cranium and the line of the snout approaches 90°. The upper jaw appears to be lacking. Both specimens exhibited no other external morphological abnormalities, although both non-pugheaded fish and the single pugheaded specimen collected in Del Puerto Creek were heavily parasitized. The belly of each specimen was distended when collected, indicating that the abnormality did not inhibit feeding ability. Both specimens have been retained by the author. 120 CALIFORNIA FISH AND GAME IW"^^^! S. * ^'H t FIGURE 2. A non-pugheaded California roach, Hesperoleucus symmetricus, above, and pughead- ed specimen fronn San Lorenzo Creek, below. FIGURE 3. A non-pugheaded California roach, Hesperoleucus symmetricus, above, and a pug- headed specimen from Del Puerto Creek, below. NOTES 121 X fj -7^ . ' >*^ ?0 o .if * FIGURE 4. A pugheaded specimen from San Lorenzo Creek, above, and a pugheaded specimen from Del Puerto Creek, below. LITERATURE CITED Alperin, I. M. 1965. Recent records of pugheaded striped bass (Roccus saxatilis] from New York. N.Y. Fish, Game |. 12(1) : 114-115. Ayres, W. O. 1849. The skull of a fish, showing a curious malformation. Proc. Boston Soc. Nat. Hist. 13 : 121. Bortone, 5. A. 1971. Pugheadedness in the vermilion snapper, Rhomboplites aurorubens, in the northern Gulf of Mexico. Trans. Amer. Fish. Soc. 100(2) : 366-368. 1972. Pugheadedness in the pirate perch, Aphredoderus sayanus (Pisces; Aphredoderidae), with implications of feeding. Chesapeake Sci. 13(3) : 231-232. Briggs, P. T. 1966. A pugheaded tautog. N.Y. Fish, Game ). 13(2) : 236-237. Cheek, R. P. 1965. Pugheadedness in an American shad. Trans. Amer. Fish. Soc. 94(1) : 97-98. Croker, R. S. 1931. A pug-headed rainbow trout. Calif. Fish. Game 17(4) : 488-489. Dawson, C. E. 1964. A bibliography of anomalies of fishes. Gulf Res. Repts. 1 (6) : 308-399. 1966. A bibliography of anomalies of fishes — supplement 1. Gulf Res. Repts. 2(2) : 169-176. Fasciolo, A. 1904. Due Casi di Deformazione nel Labraux lupus. Atti Societa Ligustica Scienze Naturali e Geo- graf iche 1 5 : 93-97. Forsyth, J. A. 1926. Radiographs of a pug-nosed trout. Fishing Gazette, London 93 : 189. Grinstead, B. G. 1971. Effects of pugheadedness on growth and survival of striped bass, Morone saxatilis (Wal- baum), introduced into Canton Reservoir, Oklahoma. Proc. Okla. Acad. Sci. 51 : 8-12. Gudger, E. W. 1929. An adult pug-headed brown trout, Salmo fario, with notes on other pugheaded salmonids. Bull. Amer. Mus. Nat. Hist. 58: 531-559. 1930. Pug-headedness in the striped sea bass, Roccus lineatus, and in other related fishes. Bull. Amer. Mus. Nat. Hist. 61 : 1-19. Herrick, F. H. 1885. An abnormal black bass. Science 6 : 243-244. Hickey, C. R., Jr. and H. M. Austin. 1974. Pugheadedness in the bluefish. N.Y. Fish. Game J. 21 (2) : 188-189. Honma, Y. and S. Yoshie, 1978. Studies on Japanese chars of the genus Salvelinus: IX. A pugheaded specimen of char, Salvelinus leucomaenis, from Umega-gawa River, Sado Island. Annu. Rep. Mar. Biol. Stn. Niigata Univ. 8 : 1-6. Knauthe, K. 1893a. Ichthyologische Notiz. Zoologischer Anzeiger 16: 109-110. 1 893b . Zwei Falle von latenter Vererbung der Mopskopfigkeit bei Cyprinoiden. Biologisches Centralblatt 13:766-767. Lawler, G. H. 1966. Pugheadedness in perch, Perca flavescens, and pike, Esox lucius, of Heming Lake, Manitoba. Can. Fish Res. Board J. 23(11) : 1807-1808. 122 CALIFORNIA FISH AND GAME Leidy, R. A. 1984. Distribution and ecology of stream fishes in the San Francisco Bay drainage. Hilgardia. 52(8) : 175p. Mansuetti, R. J. 1958. Eggs, larvae, and young of the striped bass, Roccus saxatilis. Maryland Dept. Res. and Educ, Contrib. 112: 1-35. 1960. An usually large pugheaded striped bass, Roccus saxatilis, from Chesapeake Bay, Maryland. Chesapeake Sci. 1(2) : 111-113. Mazza, F. 1893. Enteromorphie di Alcuni Pesci Marini. Atti Societa Ligustica Scienze Naturali e Geografiche 4 : 432-434. Panceri, P. 1872. Catalogo Sistematico del Cabinetto Anatomia Comparata nella Regia Universita degli Studi di Napoli, Supplemento Primero, Napoli, p. 63. Pellegrin, J. 1908. Sur une Race Monstreuse de Perches a Tete de Dauphin. Bull. Societe Zoologique France 33 : 25-26. Rondelet, C. 1555. Universae Aquatilium Historiae Pars Altera. Lyons. Rose, C. D. and A. H. Harris. 1968. Pugheadedness in the spotted seatrout. Quart. ). Fla. Acad. Sci. 34(4) : 268-270. Schwartz, F. J. 1965. A pugheaded menhaden from Chesapeake Bay. Underwater Natur. 3(1) : 22-24. Smith, F., Jr. 1967. An occurrence of pugheaded striped bass. Underwater Natur. 4(2) : 39-40. Sutton, A. C. 1913. On an abnormal specimen of Roccus lineatus with especial reference to the eyes. Anatomical Record 7: 195-199. Talen, L. G. 1975. Pugheadedness in the longspine combfish, Zaniolepis iatipinnis, from Monterey Bay, California. CaliL Fish. Game 61(3) : 160-162. — Robert A. Leidy, Department of Forestry and Resource Management, Univer- sity of California, Berkeley 94720. Mr. Leidy's current address is: 1 109 Kains Avenue, Albany, CA 94706. Accepted for publication July 1984. MILKFISH, CHANOS CHANOS (FORSSKAL, 1775), TAKEN IN SOUTHERN CALIFORNIA ADDS NEW FAMILY (CHANIDAE) TO THE CALIFORNIA MARINE FAUNA Six milkfish, Chanos chanos, taken in 1982 and 1983 establish the presence of the family Chanidae in California. On 22 March 1982 fisherman Luigi San Filippo caught an unusual fish while gill netting for striped mullet, Mugil cephalus, with a 3%-inch mesh net, in the warm water discharge plume of a south San Diego Bay power plant (lat 32° 36' 30" N, long 117° 06' 30" W). One of us (JMD) was contacted and identified the fish as a 925 mm total length (tl), 680 mm standard length (sl), 5.6 kg, milkfish ( Figure 1 ) . The specimen is deposited at Scripps Institution of Oceanog- raphy, Division of Marine Vertebrates (SIO 82-22). r" i: ' FIGURE 1. C/7dnos chanos taken by Luigi San Filippo in south San Diego Bay, March 22, 1982. Rule is 305 mm. Photograph by John M. Duffy. Two other fishermen caught milkfish off the southern California coast in 1982 and one was taken in 1983. On 7 August 1982 a specimen was taken just outside the San Pedro breakwater (lat 33° 42' 25" N, long 118° 15' 00" W) by John Guglielmo in a gill net. The late John E. Fitch, California Department of Fish and Game, retired, identified the fish and determined its length to be 970 mm TL, 745 NOTES 123 mm SL, and its weight to be 7.3 kg. It is deposited at the Natural History Museum of Los Angeles County (LACM 42887-1 ). On 9 August 1982 three more milkfish were taken in the San Diego area. Fisherman Mike Irey caught them in a GYj-inch mesh gill net set in heavy kelp (Macrocystis sp.) off Point Loma, near the entrance to San Diego Bay (iat 32° 41' 00" N, long 117° 16' 00" W). Denyse Racine, California Department of Fish and Game, identified the fish, measuring 1024 mm tl, 1047 mm tl, and 1055 mm TL and weighing 7.9 kg, 9.3 kg, and 8.6 kg, respectively. All three fish were sold for food. On 30 December 1983 Stephan FHadley snagged a milkfish with an artificial lure, in Quivira Basin, Mission Bay (Iat 32° 45' 45" N, long 117° 14' 15" W). Sportsmen's Seafood Market retained the fish until Hannah Bernard and Bob Read, California Department of Fish and Game, identified the specimen as a 1010 mm TL, 765 mm SL, 7 kg, milkfish. Richard Rosenblatt, SIO, examined the fish and determined that it was a mature female with inactive oocytes. The fish is deposited at SIO (SIO 83-177). Schuster (1960) reported the world wide range of C chanos to include the tropic and subtropic sections of the Indian and Pacific Oceans, 30° to 40° N to 30° to 40° S Iat and 40° E to 100° W long. Neither Miller and Lea (1972) nor Hubbs, Follett, and Dempster (1979) included its range along the California coast. Fowler (1938) added the Galapagos Islands and Chirichigno (1978) the coast of Peru for recent uncommon records of C. chanos; yet the milkfish is not uncommon in the Gulf of California from Guaymas to Mazatlan ( Evermann and Jenkins 1981, Jordan 1895, Thomson and McKibbin 1976). Migdalski and Fichter (1976) suggest the possible presence of C chanos along the coast of "lower California," which we infer from historical usage to mean Baja California, Mex- ico. Eschmeyer, Herald, and Hammann (1983, p. 63) note that the milkfish "occasionally strays to S. Calif."; this information was provided by the late John E. Fitch (William N. Eschmeyer, California Academy of Sciences, pers. com- mun.). In 1877, 100 milkfish were brought to California from Hawaii in exchange for salmon and trout eggs (Calif. Comm. of Fisheries 1877). The fish were intro- duced in a small stream at Bridgeport, Solano County. There is no record of their survival. There have been, however, three reports of the milkfishes' appearance along the coast of Baja and southern California during the last 55 years. Clark (1929) reported a specimen in a San Pedro fish market that had been taken "off the western coast of Lower California." A milkfish was observed floating dead in south San Diego Bay, also in 1929 (John E. Fitch, pers. commun.). Not until May 1979 was another specimen noted. San Diego fisherman Ed Simpson caught a milkfish on hook-and-line in south San Diego Bay, near where San Filippo's fish was taken. Richard Rosenblatt, SIO, identified the specimen as a milkfish from the remains of the caudal peduncle and caudal fin which are deposited at SIO (SIO 79-345). The 1982 specimen from off San Pedro represents a northern range extension of approximately 1786 km from an area off the west coast of Mexico between Mazatlan and Guaymas (Figure 2). We believe that this locale is the most likely source for these fish. Our specimens were all large and presumably adult fish (maximum reported size 1.7 m — in Nelson 1976) which would easily be able to make the journey to our coastline. 124 CALIFORNIA FISH AND GAME } Pb vJ-^^^ " ^ ^ 1%^ — ^~x A k MEXICO ^ +3^Jf §i v^;- % ^\ ^ mazatlanS i f \ , 33" N ' ^118° W ) \ + 33° N \v:. 117° W \MISSION BAY 31 MILES (iyO. DIEGO 50 KM 1 FIGURE 2. Chanos chanos catch locations in southern California. Inset is not to scale. ACKNOWLEDGMENTS We thank fishermen L. San Filippo, J. Cuglielmo, M. Irey and S. Hadley for their recognition of these unusual fish and their cooperation in obtaining infor- mation relative to the captures. R. H. Rosenblatt, SIO, and C. C. Swift and R. J. Lavenberg, LACM, allowed us access to their respective fish collections and provided assistance. California Department of Fish and Game employees assisted us in many ways. D. Racine provided the information on key's fish. R. Read assisted in examining NOTES 125 Hadley's fish. R. N. Lea and H. W. Frey both provided references, reviewed the manuscript, and provided helpful comments. G. Quiros checked all literature citations. The late J. E. Fitch provided measurements of the San Pedro specimen and references, observations, and encouragement unobtainable from any other source. D. Gittings, National Marine Fisheries Service and P. Leverenz, SIO, provided assistance in obtaining references. LITERATURE CITED Calitornia Commissioners of Fisheries. 1877. Report of the Commissioners of Fisheries of the State of California for the years 1876 and 1877. 30 p. Chirichigno F. N, 1978. Nuevas adiciones a la ictiofauna marina del Peru. Inst, del Mar del Peru Informe No. 46. 109 p. Clark, F. N. 1929. Specimen of milkfish, Chanos chanos, delivered at San Pedro. Calif. Fish Came 15(2):175. Eschmeyer, W. N., E. S. Herald, and H. FHammann. 1983. A field guide to Pacific coast fishes of North America. Houghton Mifflin Co., Boston. 336 p. Evermann, B. W., and O. P. Jenkins. 1891. Fishes from Cuaymas. Proc. U.S. Natl. Mus. 14 (846);121-165. Fowler, H. W. 1938. The fishes of the George Vanderbilt South Pacific Expedition, 1937. Monog. Acad. Nat. Sci. Phila. 2:1-349. Hubbs, C. L., W. I. Follett, and L. ). Dempster. 1979. List of the fishes of California. Occas. Pap. Calif. Acad. Sci., No. 133:1-51. Jordan, D. S. 1895. The fishes of Sinaloa. Proc. Calif. Acad. Sci., 5 (ser. 2):377-514. Migdalski, E. C, and C. S. Fichter. 1976. The fresh & salt water fishes of the world. Alfred A. Knopf, Inc., New York. 316 p. Miller, D. J., and R. N. Lea. 1972. Guide to the coastal marine fishes of California. Calif. Dept. Fish Came, Fish Bull. 157:1-235. Nelson, J. S. 1976. Fishes of the world. John Wiley and Sons, Inc., New York. 416 p. Schuster, W. H. 1960. Synopsis of biological data on milkfish, Chanos chanos (Forskal), 1775. FAO Fish. Biol. Synop. 4:1-58. Thomson, D. A., and N. McKibbin. 1976. Gulf of California fishwatcher's guide. Golden Puffer Press, Tucson, Ariz. 75 p. —John M. Duffy, California Department of Fish and Game, 1350 Front Street, Marine Resources Region, San Diego, CA 92101, and Hannah J. Bernard, National Marine Fisheries, Southwest Fisheries Center, 8604 La Jolla Shores Drive, La jolla, CA 92038. Accepted for Publication January 1984. EXPERIMENTAL LEAD DOSING OF NORTHERN PINTAILS IN CALIFORNIA As a result of the decision by the U.S. Fish and Wildlife Service (FWS) to implement steel shot regulations in selected areas of the Pacific Flyway (FWS 1976) the California Department of Fish and Came (DFC), in cooperation with FWS began intensive investigations into waterfowl lead poisoning in 1974. A dosing study was considered a possible means of indirectly measuring mortality from ingested lead. By examining band recovery rates of birds shot in years after banding, it should be possible to measure differences in survival between dosed and undosed birds. This experiment assumes an equal probability that dosed and undosed birds will be recovered, given that they survive to the beginning of the hunting season following banding. The study was designed by DFC in coopera- tion with FWS, which also provided funds. The northern pintail was chosen as the species to test because it is the most abundant wintering duck in California, is highly sought after by hunters, is known to ingest lead, and can be trapped in large enough numbers to be meaningful. The original goal was to trap 15,000 birds after the close of the hunting season and dose half of these with lead shot. 126 CALIFORNIA FISH AND GAME METHODS Pintail were trapped in 7 areas of the Central Valley, from Mendota Wildlife Area, Fresno County, in the south, to Sacramento National Wildlife Refuge, Glenn County, in the north, and at Lower Klamath National Wildlife Refuge, Siskiyou County, in the Klamath Basin. Trapping took place from 22 January 1 979 to 23 March 1979. Standard swim-in funnel traps baited with barley were used at all trap sites. As each bird was removed from the trap it was sexed and banded, after which a plexiglass tube was inserted into the esophagus as far as the crop. Two No. 5 lead pellets were placed in the tube in every other duck of each sex. This dosage was chosen as best approximating i) the average amount of lead found in pintail gizzards examined during studies of ingestion rates in California, and ii) the dosage used by Bellrose (1959) in his work on Illinois mallards. Birds were released immediately after dosing. Tubes were dipped in an antiseptic solution between each usage to prevent the potential spread of disease. In an effort to increase hunter reporting rates (George Jonkel, Bird Banding Laboratory, USFWS, pers. commun.) red, anodized, aluminum bands were used in this study. In addition, a press release was issued and sportsmen's groups were contacted in person to describe the purpose of the project. RESULTS AND DISCUSSION Trapping yielded 12,263 birds, of which 6,109 were dosed and 6,154 served as controls. The unequal number of banded birds in the two groups at a particu- lar banding station (Table 1 ) was due to the tendency of crews to begin banding each day, or at each trap, with the same treatment regardless of the treatment last used at the previous trap. As of May 1, 1984, 854 recoveries had been obtained (Table 1 ). Only recoveries from birds shot or found dead during the hunting season were used for analysis of recovery rates. The overall recovery rate, males and females combined, through the first hunting season after banding was 2.8%. Average recovery rate through the first hunting season for pintail banded at Gray Lodge Wildlife Area (1974-1978) was 3.1%. The difference is insignificant (x2 = 0.61,P < 0.005). Birds retrapped during the preseason banding period of 1979 had already lost much of the red coloring from their bands. It is possible that hunters just didn't notice the different nature of the anodized bands, or that return rates may actually have been negatively influenced by the publicity about the study. Some hunters may have felt they would be contributing to a steel shot require- ment if they participated. In any case, the attempts to increase reporting rates were not successful. The central question of this study is whether lead dosage resulted in decreased survival probabilities of winter-banded pintails. The recovery rate of a group of pintails can be thought of as the product of survival probability and recovery probability. Since there is no reason to reject the assumption of equal probability of recovery between dosed and control groups, recovery rates can be used as a measure of the probabilities of survival. Chi square tests showed insignificant differences (P<0.05) in recovery rates among banding sites for each sex-treatment group, permitting pooling of the samples. A one-tailed test for the difference in recovery rates between dosed and control birds was then computed for males and females, respectively. The results NOTES 127 J; ■J 1> CO CO o r-v r^ CO r~^ <— u-i CTv CO ro - O oo ■q- SI — Ln rn m ro o^ o o o o o OOOOOOOOO s ^-2 un Lo 1 — \^ O^ O^ 1 — CO rsi 1 — in rs) ^d vX)r^^LnCT^O^cO'^£>u^LO coa^o^co^^r-~^^Lnco OOOOOOOt— o OOOOOOOOO o o CO r^ O CO ^o LH O LTl r-j CT^ r~^ o o> c O 1/1 u l/l o .s *c u ■o &i "O c CQ c5 8 2 & o -— O O O O ■— CO -^ t-M r^j ui Ln . — Lo <-n r-^ LT) -^r ro -^ rsi r\ ■^ i-v O 1 — O o o o o o o ^ CO 5 CO r^ CO m CO ro CO i ' T3 -° ^ U-) -=: ■^ E ^-2 8 2 03 t O rsi rsi .— Tj-rsiv^r^rsimLno-^ rNCO"— r^cOLn-— ■^co rOvX)' — "^v^LOh^cTiO^^^I "t-^i— .— h^LOI^OCO"— _ ,^^o^^x>■g■cooovD^^ oodoooooooo ooooooooooo 5 CO ■p 9j ■* rsi LO O ro 3 p » — m 'T ^ ^ i 03 ~o -Q -& CM a^ 1 — rg ^ rn rsj r^ O ■^ Oi s ^ rn LT, rs ■^ ro CO !-s| u~i r^ un O c 0^ 1^ ul ro r-. ? 3 T: 3 s ^ -Q s 01 > o w ca < Oq <-s| 1 m 3- ■< n: ■a ^ O O •— 5 ^^ CM : O^ ,— ^ — ^ rvi T— (^ I rN ^ ro ■ — ■ 0^ a^ ^ $ — > Z Qi g Oi 3 o (/I Q. >- CO o O •S o E c: > O > s m z 0 o > CD « 90 m as *" Ti -4 _ n IM s <^ — 1 s> = 2. m £g c: 55 > 9 2'S c iJ -♦ a >S^ SS^ > -t •o — m -*l