Biological Services Program FWS/OBS-80/37 December 1980 Catalog of California Seabird Colonies Bureau of Land Management Fish and Wildlife Service U.S. Department of the Interior From the collection of International Bird Rescue Research Center Cordelia, California in association with z ^ m oPre ibrary San Francisco, California 2006 ;ram was established within the U.S. Fish and Wildlife ..nation and methodologies on key environmental issues purees and their supporting ecosystems. The mission of [and Wildlife Service in its role as a primary source of fish and wildlife resources, particularly in respect [assessment. nesent information that will aid decisionmakers in the jtion of problems associated with major changes in gical information and evaluation for Department of programs, such as those relating to energy develop- Biological Services Program is intended for use in the ESS to prevent or minimize the impact of development ;ivities and technical assistance services are based on an ation of the decisionmakers involved and their infor- [of the state of the art to identify information gaps is a strategy that will ensure that the products pro- knd useful. [the following areas: coal extraction and conversion; land oil shale development; water resource analysis, |stern water allocation; coastal ecosystems and Outer id systems inventory, including National Wetland [analysis, and information transfer. consists of the Office of Biological Services in ible for overall planning and management; National central scientific and technical expertise and arrange tudies with states, universities, consulting firms, and a link to problems at the operating level; and staff at rch facilities, who conduct inhouse research studies. . ^>/uu. j71 p. in and G.S. Lester. 1980. Catalog of California |of Interior, Fish and Wildlife Service, Biological Questions or requests for this pubUcation should be directed to: Information Transfer Specialist National Coastal Ecosystems Team U.S. Fish and Wildlife Service NASA - Slidell Computer Complex 1010 Cause Boulevard Slidell, Louisiana 70458 FWS/OBS-80/37 December 1980 Catalog of California Seabird Colonies by Arthur L. Sowls, Anthony R. DeGange, Jay W. Nelson and Gary S. Lester Editorial Assistants Mary B. Evans Cherry Keller Project Officer Jay F. Watson U.S. Fish and Wildlife Service Lloyd 500 Building, Suite 1692 500 N.E. Multnomah St. Portland, Oregon 97232 Field Assistants William E. Rodstrom Margaret A. Stewart CONTRIBUTORS The following people were involved in surveys of seabird colonies covered by this report. Without their efforts, this catalog would not have been possible. Steve Abbore David G. Ainley Daniel W. Anderson Jonathan L. Atwood Douglas Ayers Alan Baldridge Linda Belluomini Carl Benz Lynn C. Bemer Lawrence C. Binford Robert J. Boekelheide Kenneth T. Briggs James R. Chambers Howard L. Cogswell Paul Collins Elizabeth Copper Mary Ann Danielson Anthony R. DeGange Craig Denson Richard A. Erickson Michael Evans Bill Everett Alan K. Fukuyama Ron Garrett Robert E. Gill Sharon Goldwasser Franklin Gress Stanley W. Harris Thomas E. Harvey Valerie Hironaka Harriet R. Huber George L. Hunt, Jr. Ron Jameson Ronald M. Jurek Paul R. Kelly Gary S. Lester Ronald A. Le Valley David B. Lewis T.James Lewis David A. Manuwal Barbara Massey Stephen H. Morrell Tim McKay Maria Joyce Nakagawa Maura Naughton Jay W. Nelson John S. Nelson Audrey Newmjin Timothy O. Osborne Robert L. Pitman Mark Rauzon Gordon Reetz Jack G. Reynolds William E. Rodstrom Fred C. Sibley Fred Sorensen Arthur L. Sowls Steven M. Speich Margaret A. Stewart Gary Strachsui Craig Strong Laurie Stuart Philip Unitt Daniel H. Varoujean Michael C. Vasey Jay F. Watson Kathy Winnett This study was funded by the Bureau of Land Management, Pacific Outer Continental Shelf Office, under Memorandum of Understanding No. AA551-MU9-13. Published by Coastal Ecosystems Project Office of Biological Services Fish and Wildlife Service U.S. Department of the Interior Washington, DC 20240 For sale by the Superintendent of Documents, U.S. Government Printing OfDce, Washington, D.C. 20403 ACKNOWLEDGMENTS A project of this magnitude would not have been possible without the assistance of many individuals and organizations. Jay F. Watson, our Project Officer, was paramount in managing this study and provided us with encouragement and advice throughout the project. Bill Rodstrom's able field assistance during the 1979 field season played a prin- cipal role in the completion of this project. He was responsible for data collection for much of the north coast. Margaret Stewart's help during the 1980 field season and with the pre- paration of this report were invaluable. Gary Rankel of the U.S. Fish and Wildlife Service in Areata, California graciously provided us with office space, a congenial work atmosphere, and access to a copy machine. Paul Springer, also of the U.S. Fish and Wildlife Service in Areata, kindly provided us with space to store our equipment. The following organizations loaned us equipment for which we are grateful: U.S. Fish and WildUfe Service, Anchorage, Alaska and Sacra- mento, California; San Francisco Bay National Wildlife Refuge; and Washington State Fisheries Cooperative Unit. Data from many investigators were incorporated into this report. Without their co- operation this project would not have been possible. We thank all of those people Usted on the title page who were involved in these recent collections of data. Special thanks in this regard go to Dave Ainley, Dan Anderson, Jonathan Atwood, Bob Boekelheide, Ken Briggs, Alan Craig, Elizabeth Copper, Frank Gress, Stan Harris, George Hunt, Jr., Ron Jurek, Paul Kelly, Tim Osborne, and Dan Varoujean. We thank the many individuals of the California State Park System and the California Department of Fish and Game for assistance in many ways. John Warrick, of the Pacific Gas and Electric Company, arranged access to the Diablo Nuclear Power Plant and Jim Chambers assisted us with our surveys there and made his field notes available to us. Several aerial surveys were done with the cooperation of the U.S. Coast Guard. We would par- ticularly like to acknowledge Lt. Sutter Fox of the Areata Air Station for arranging logis- tic support. Jim Bartonek, Ron LeValley, Paul Springer, and Mark Strong reviewed an early draft of this report and their suggestions were most helpful. Dave Ainley, Dan Anderson, George Hunt and Stan Harris reviewed the final draft and added many useful refinements. We are much indebted to Linda Parkinson and Margaret Stewart who donated several of the drawings which adorn the pages of this catalog. Allen Brooks' drawing of the Mar- bled Murrelet was provided courtesy of The Murrelet, A Journal of Northwestern Orni- thology and Mammalogy. Help with maps was provided by Richard Huxley and Larraine Strong. Dave Van de Mark printed our photographs. Drafts of this report were typed by Maria Collins and Bemadene Logan, and typesetting was done by Kathy Amyotte and Jeannie Jacobsen. Finally, we thank the Bureau of Land Management for sponsoring this project and in particular Gordon Reetz of the Pacific Outer Continental Shelf Office. u TABLE OF CONTENTS INTRODUCTION 1 THE NATURE OF SEABIRDS 1 THREATS TO SEABIRDS 2 METHODS 7 DISCUSSION 11 SPECIES ACCOUNTS: Fork-tailed Storm-Petrel (Oceanodroma furcata) 20 Leach's Storm-Petrel (Oceanodroma leucorhoa) 22 Ashy Storm-Petrel (Oceanodroma homochroa) 24 Black Storm-Petrel (Oceanodroma melania) 26 Brown Pelican (Pelecanus occidentalis) 28 Double-crested Cormorant (Phalacrocorax auritus) 30 Brandt's Cormorant (Phalacrocorax penicillatus) 32 Pelagic Cormorant (Phalacrocorax pelagicus) 34 Black Oystercatcher (Haematopus bachmani) 36 Western Gull (Lams occidentalis) 38 Common Murre (Uria aalge) . . 40 Pigeon Guillemot (Cepphus columba) 42 Marbled Murrelet (Brachyramphus marmoratus) 44 Xantus' Murrelet (Endomychura hypoleuca) 46 Cassin's Auklet (Ptychoramphus aleuticus) 48 Rhinoceros Auklet (Cerorhinca monocerata) 50 Tufted Puffin (Lunda cirrhata) 52 MAPS AND TABLES: How to Use Maps and Tables 56 Map Index 57 Section 325, Eureka 58 Section 379, Ukiah 106 Section 404, Santa Rosa 142 Section 429, San Francisco 180 Section 454, Monterey 212 Section 477, San Luis Obispo 236 Section 501 , Santa Maria 260 Section 502, Los Angeles 282 Section 524, Long Beach 298 Section 525, Santa Ana 318 Section 545 , San Diego 326 REFERENCES 341 APPENDIX A: Data Archives 35 1 APPENDIX B: Observation Points for Seabird Colonies 355 APPENDIX C: Index of California Seabird Colonies 366 m S*. Ga^f-f* Car* MvMlecin* C«p« Viicain* f •inl Ar*na^ ■ed«f o H«ad^ P«inl R«y«t ft^.D' San Fran< isco ^\ PiHor Points ^o Point Ane Nu«vo\San»a Cruz ( Point Sur\ Mont*r«> Capo Son Martin Point Piodro* Blancat Point ftuchon Point Sal Point Arguollo Point Concoptien CMANNa lUANOS IV INTRODUCTION This catalog is a summary of the location, size, and species composition of seabird colonies along the California coast. It documents more than 260 nesting areas with a total estimated population of nearly 700,000 birds. Our study was sponsored by the Bureau of Land Management, Pacific Outer Continental Shelf Office, to fulfill requirements of the Nation- al Environmental Policy Act of 1970. The information will help resource planners evaluate possible effects on seabirds of proposed oil and gas leasing. Detailed information on seabird distribution and abundance will be useful to coastal planners, scientists, and amateur bird- watchers. For this reason, we have included a section on threats to seabirds and appendices on the archiving of our field data (Appendix A) and viewpoints from which several colonies can be observed without causing disturbance (Appendix B). Seventeen species of seabirds from six families are discussed in this report. These include four species of storm-petrels (Fork-tailed, Leach's, Ashy, and Black), one species of pelican (Brown Pelican), three species of cormorants (Brandt's, Double-crested, and Pelagic), one species of shorebird (Black Oystercatcher), one species of gull (Western Gull), and seven species of alcids (Common Murre, Pigeon Guillemot, Marbled Murrelet, Xantus' Murrelet, Cassin's Auklet, Rhinoceros Auklet, and Tufted Puffin). In addition to population information in the maps and tables, species accounts discuss aspects of the natural history of each of the above species, emphasizing the California populations. Population information for six additional species which could also be affected by coastal development and pollution has been included in the maps and tables. All the known locations of Least Tern (Sterna albifrons) colonies are iden- tified in this catalog, although yearly surveys by the California Department of Fish and Game will soon render this data obsolete. The catalog also identifies coastal breeding sites of the Caspian Tern, (Sterna caspia), Forster's Tern (Sterna forsteri), and Black Skimmer (Rynchops niger), species which also breed inland. The single known California nesting location of the Elegant Tern (Sterna elegans) in San Diego Bay is also identified. Finally, locations of known Heer- mann's Gull (Larus heermanni) nest sites are indicated, although this species was never re- corded breeding in California until 1980, and cannot be considered part of the normal breeding avifauna. All six species, except Heermann's Gulls and some Least Terns, nest and feed pri- marily in enclosed bays and estuaries. Our inclusion of this information is intended only to supplement other sources of information on these species. It must be recognized that this report only documents nesting sites. Large numbers of non-nesting birds migrate through coastal CaUfomia in spring and fall and many additional birds winter along the coast. These include shear- waters from as far away as New Zealand and Tasmania, many kindsofshorebirds and waterfowl from arctic Alaska and Canada, pehcans and gulls from Mexico, and inland nesting birds such as grebes and small gulls. Oil spills and other dis- turbances could severely affect these populations. Seabirds are truly an international resource and must be managed as such. THE NATURE OF SEABIRDS Seabirds evolved in an environment free of most of the competition and predators faced by terrestrial birds. They have evolved into birds with long lifespans, low adult mortality rates, relatively late sexual maturity, and small clutch sizes. Lifespans of seabirds are not exactly known, but they are certairriy long in comparison to most terrestrial birds. Records exist of indivi- duals of several species of seabirds reaching more than 20 and even 30 years of age (Bergstrom 1952, Clapp and Sibley 1966, Clapp and Hack- man 1968, Graham 1980). Long Ufespans in a species imply a low annual rate of adult mor- tality, and annual mortality rates below 20 percent are common in seabirds (Ashmole 1971, Richdale and Warham 1973). Some albatrosses may have annual mortaUty rates as low as three percent (Lack 1954). Many passerines, at the other extreme, have annual mortality rates from 40 to 70 percent (Lack 1954). If mortality rate remains constant with increasing age, large seabirds with very low annual mortahty rates may attain a breeding life of50 years or more (Ashmole 1971). In addition, recruitment of birds into the breeding population is often slow and delayed. Before attaining maturity, many seabirds spend at least 2 years, and more commonly 3, 4, 5, and up to 9 years as non-breeders (Ashmole 1971). Long breeding lives, low recruitment rates, and delayed maturity could delay the effects of successive breeding failures on breeding populations for several years. The clutch size of seabirds is usually low. Storm-petrels and other procellariiformes lay one egg, alcids lay one or two eggs, and pelicans and gulls lay one to three eggs. Cormorants may lay up to seven eggs, though clutches of four or five are more common. By contrast, many land birds lay from 7 to 15 eggs and many produce two broods each year. Because seabirds reproduce at a slow rate but over a long lifetime, the effects of an oil spill or other disaster and the potentially more danger- ous effects of longterm chronic pollution, habitat loss, and other disturbances demand careful and frequent monitoring of seabird populations. Seabirds tend to be of two types: those which spend most of their time near shore (in- cluding cormorants, pelicans, and most gulls), and those which come to land only during the breeding season or sometimes intermittently during other times of the year (including storm-petrels and alcids). Of the truly pelagic seabirds, several are nocturnal on the breeding grounds; they will enter or leave their colonies only at night. In California, the four storm-petrels. Marbled and Xantus' Murrelets, Cassin's Auklets, and, to a lesser degree. Rhinoceros Auklets are nocturnal on their breeding grounds. The seabird colony is the most critical habitat for seabirds because reproduction and thus continuation of species depend on these sites. Here the population will reach its annual low, just before young are hatched, and its annual high, just after hatching. At other times of the year, seabirds may be able to avoid problems such as disruption of food supplies, and perhaps even large oil spills, simply by flying somewhere else, but for successful nesting they are limited to the area around the colony. In the following section, we discuss some of the problems which face seabirds. We hope an awareness of these will alert coastal planners to the kinds of problems that may be encountered. THREATS TO SEABIRDS OIL leasing program by the Bureau of Land Manage- ment offshore of California was initiated in 1963. Areas in the Santa Barbara Channel were leased in 1 966 and 1 968 , and other sections of the Southern Cahfomia Bight were leased in 1975. Five new oil lease zones were identified offshore of central and northern California in 1977. The southern- most of these tracts is scheduled for sale in 1981. Resource planners must be aware of potential hazards to seabirds that may be caused by oil development. There is ample literature document- ing the lethal effects of oil on marine birds, including papers by Bourne (1968, 1970), Clark (1969), Clark and Kennedy (1968), CroxaU (1975), Manuwal (1978), and many others. Vermeer and Vermeer (1974) reviewed the literature appearing between 1922 and 1973 on the effects of oil on birds. One effect of oil on seabirds is destruction of the insulating properties of feathers. An oiled bird compensates for the loss of insulation and subsequent loss of heat by increasing its metabolic rate, using stored energy (Hartung 1967). If the bird's energy balance is not restored, energy reserves are soon depleted and death from hypo- thermia results. Oiled birds are unable to maintain their energy reserves because they cannot or will not feed. Marine birds may also ingest oil while drinking, feeding, and especially when oiled individuals attempt to preen their soiled plumage. Ingestion of oil may hinder the absorbtion of Oil exploration, production, and transport are important industries along the coast of California. A federal outer continental shelf A Common Murre fouled with oil on a Pacific Coast beach. Photo by Duncan McDonald water across the intestinal wall (Crocker et al. 1974). Ingested oil may also affect reproductive success. Grau et al. (1977) showed that ingested oil altered the yolk structure of recently laid Japanese Quail eggs (Coturnix coturnix) and greatly reduced their hatchabiUty. These authors are continuing their studies on the Farallon Islands with Western Gulls and Cassin's Auklets (Ainley et al. 1979). Hartung (1965) demon- strated that ingested lubricating oil reduces the egg laying rate of captive Mallards (Anas platyrhynchos). Oil applied to the exterior of eggs also reduces hatching success. This has been observed in experiments performed on the eggs of Mallards (Hartung 1965), Common Eiders (Somateria mollissima, Albers and Szaro 1978), Laughing Gulls (Lams atrkilla. King and Lefever 1979), Glaucous-winged Gulls (Larus glaucescens. Patten and Patten 1977), and Great Black-backed Gulls (Lams marinus. Coon et al. 1979, McGill and Richmond 1979). The species vulnerable to oil spills are those which are most restricted to an aquatic environ- ment, particularly loons, grebes, seaducks, and alcids, although some variation will occur depend- ing on the season. We have discussed these aspects of each species' life history in the species accounts. In California, three well-documented oil spills which killed large numbers of birds have occurred: the Santa Barbara oil spill of 1969 (Straughan 1971) and the San Francisco oil spills of 1937 and 1971 (Aldrich 1938, Moffitt and Orr 1938, Small et al. 1972). All three spills occurred in the winter which greatly influenced the species of birds killed. Wintering Western Grebes (Aechmophoms occidentalis) and loons suffered the greatest mortahty in the Santa Barbara oil spill. Western Grebes were similarly affected in the 1971 San Francisco oil spill and to a lesser extent in the 1937 spill. Common Murres and wintering scoters (Melanitta spp.) also experienced heavy mortahty from oil in the San Francisco oil spills. Common Murres breed in Cahfomia and appear in the near-shore zone periodically in the winter. CHRONIC POLLUTION AND TOXIC CHEMICALS Large oil spills are well pubhcized, but low-level chronic oil pollution, small oil spills, and the build-up of other pollutants probably pose a more serious long-term threat to seabirds. Pollu- tants of particular concern, other than oil, include pesticides and their residues, heavy metals, polychlorinated biphenyls and other by-products of industry, and plastic particles. Most seabirds are long-lived and feed at or near the tops of their food chains. Certain pollu- tants such as DDT and its principal metabohte DDE are stored in the body and concentrate in increasing amounts at each higher level in the food chain. When concentrations of these chem- icals reach sufficiently high levels, reproduction may be impaired or death may occur. Seabirds constitute one of the most conspicuous and easily studied components of the marine ecosystem, so their reproductive failure or death may be our first indication that the environment contains dangerous quantities of toxic chemicals. In Minamata, Japan, high levels of mercury in effluent from a vinyl chloride plant were first manifested in the deaths of fish-eating birds. This was followed by the tragic deaths of many humans (Kurland et al. 1960). The effects of pollutants on seabirds can be monitored by close study and may serve as a valuable indicator of the health of marine ecosystems. For this reason alone, continued study of certain seabird popula- tions will be useful. The effects of chlorinated hydrocarbon pesticides and their residues and polychlorinated biphenyls on birds are well documented (Peakall 1970, 1975). These contaminants reduce breeding success by decreasing fertility, reducing the viabiHty of eggs and chicks, and interfering with calcium deposition, resulting in the production of thin eggshells which may later break. Physical abnormahties have also been associated with organochlorine residues (Hays and Riseborough 1972). In California the Brown Pehcan has become a symbol in the fight against pollution of the world's oceans. The reproductive success of Brown Pehcans was seriously reduced by the presence of DDT, DDE, and related chemicals in the ocean off southern California. Because of eggshell thinning, most eggs were broken before the young hatched and only 12 chicks fledged out of 2,368 nesting attempts in 1969, 1970, and 1971 (Gress et al. 1973). Double-crested Cormorants suffered a similar decrease in reproductive success in southern Cahfomia and Mexico (Gress et al. 1973). These reproductive failures were traced to DDT dumped into the Los Angeles sewer system by a chemical manufacturing plant. Since April, 1970, these wastes have been deposited in a landfill and DDT input into the ocean has declined significantly (Anderson et al. 1975). Reproductive success of both Brown Pelicans and Double-crested Cormorants has improved dramatically and the population of Brown Pelicans may be on its way to recovery (Anderson et al. 1975). Chlorinated hydrocarbons and poly- chlorinated biphenyls have also been linked with shell thinning of Ashy Storm-Petrel and Common Murre eggs on the Farallon Islands (Coulter and Riseborough 1973, Gress et al. 1973). Many other populations of seabirds in North America ha\ ' i; 1 1 ' ffocted by these contaminants. This Brown Pelican egg was broken under the weight of incubating adults as a result of thin eggshells from pesticide contamination. Photo by Frank Gress. Plastic particles are commonly found in the stomachs and gizzards of seabirds collected for scientific study (Baltz and Morejohn 1976, Rothstein 1973). It is likely that seabirds mistake these for larval fish, eggs, or other foods floating on the ocean surface. These particles enter the environment by physical breakdown of the huge quantities of plastics which are dumped into the world's oceans each year. The physical presence of plastic particles may affect the health of birds. Particles which accumulate in the gizzard probably are not as effective as the pebbles normally used to grind up food. Fortunately, plastics are nearly chemically inert and are unlikely to affect birds the way toxic chemicals do. More research on this topic and concern about the "garbage can" attitude we have toward our oceans are needed. FISHERIES Commerical fisheries can affect seabirds in three primary ways: 1) birds drown in gillnets, 2) offal from fishing boats provides an additional food supply for certain seabird species, and 3) extensive fisheries deplete some seabird prey species. Depletion of prey fishes presently seems to be the major fisheries-related threat to seabirds in California. Gillnet drowning and offal discharge have dramatically affected seabirds in other parts of the world. Seabirds drown in gillnets when they are caught while diving or plunging into the water for food. The alcids, which dive to feed, and shear- waters (Puffinus spp.), which plunge into the ocean to feed, are among the most vulnerable of seabirds. The salmon driftnet fisheries of the North Atlanfic and North Pacific Oceans have caused high mortality of seabirds. The Danish salmon fishery off West Greenland killed an estimated 500,000 to 750,000 Thick-billed Murres (Uria lomvia) annually between 1968 and 1975 (Tull et al. 1972). In the North Pacific, the Japanese salmon mothership fishery kills over 200,000 seabirds in gillnets each summer (Ainley et al. in prep.), and large numbers of seabirds die in the Japanese land-based fishery as well (Sano 1978). Restriction of gillnet fishing near colonies and in regions of known high seabird concentra- tions at sea could reduce this kill. The large incidental kill of Thick-billed Murres in the Danish fishery was curtailed after an international agreement took effect in 1976, restricting the Danish fishery to only coastal waters (Salomonsen 1979). The Japanese fishery, although reduced in size in recent years, is still very active in the North Pacific. The only salmon gillnet fishery In California is located in the Klamath River of northern California. Some birds drown in the nets of this fishery each summer (Chatto pers. comm.) but the total number of birds killed is small. An unknown number of seabirds are killed annually in a small coastal gillnet fishery for bottomfish that operates from Tomales Bay south to Santa Barbara (Miller pers. comm.). Common Murres, cormorants, and Sooty Shearwaters (Puffinus griseus) are apparently the species most frequently caught. Although this fishery has existed for at least 50 years, it has only recently become large enough to cause concern. The California Department of Fish and Game and the U.S. Fish and Wildlife Service are currently investigating the mortahty of marine birds and mammals in this fishery. Offal from boats, particularly processing ships associated with large whahng and fishing fleets, provides large amounts of food for some seabird species, especially Northern Fulmars (Fulmanis glacialis) and gulls. This new food supply may be in part responsible for increases in fulmar and gull numbers in some parts of the world (Brown 1970, Bourne 1972). Commerical fishing in California is primarily from small, privately-owned boats and offal discharge is probably insignificant at present. Coastal garbage dumps are likely a more important food source for gulls. Commerical fisheries are increasingly harvest- ing species of fish used by seabirds for food. This is due largely to an increasing demand for fish products, depletion of more desirable species, and improved fishing technology. Fish stocks can become so depleted through overfishing that decreases in populations of seabirds can result. This is best illustrated by the crash of Peruvian seabird populations following overfishing of the anchoveta (Engraiilis ringens). In the years between 1953 and 1965, Peruvian seabird popula- tions declined from 28 million birds to 4 million birds (Schaefer 1970). A similar conflict seems likely to occur between the Northern Anchovy (Engraulis mordax) and seabird populations along the west coast of Mexico and southern California. The diet of breeding Brown PeUcans in southern Cahfornia has been found to contain 92 percent anchovies (Gress pers. comm.). Brown Pelicans reproduce best during periods when anchovies are abundant near breeding colonies (Anderson et al. 1980). Although pre-1979 harvest levels of anchovies probably did not affect Brown Pelican reproduction, potential increases in the harvest proposed under some options of the Anchovy Management Plan, Pacific Fisheries Management Council, could be serious (Anderson et al. 1980). Hunt and Butler (1980) have shown the im- portance of anchovies to the reproductive success of Xantus' Murrelets and Western Gulls on Santa Barbara Island (524 008, See page 56). Protecting seabird feeding areas, particularly those near breeding colonies, may be necessary. Caution should be used before any decision to increase anchovy harvests is made (MacCall 1974, Radovich 1979, Anderson et al. 1980). Little information is available on the effects of fisheries- caused depletion of prey species on other California seabirds and continued research is needed (Anderson et al. 1980). HUMAN DISTURBANCE A serious danger to nesting seabirds is disturbance by people, including scientists, bird- watchers, recreationahsts, and others. Disturbance is usually unintentional and, more often than not, the culprits are unaware of the harm that they have caused. When people go into or near a seabird colony they can cause disturbance in many ways. An awareness of potential problems can do much to reduce disturbance. Flushing birds from nests must be avoided since it can cause adults to abandon nests, exposes eggs and chicks to predators, and interferes with incubation and the feeding of chicks. During panic departures adults may even break eggs or kick eggs and chicks from nests. Larger chicks may run off and, unable to get back to the nest, may die or be killed. Airplanes, boats, and helicopters, as well as individuals on foot, can cause birds to flush by approaching a colony too closely. Helicopters are especially disruptive. In Cahfornia, predation on uncovered eggs and chicks is primarily by Western Gulls and Common Ravens (Corvus corax). Both gulls and ravens patrol colonies in search of unattended eggs and chicks or for a chance to steal food brought in by parent birds. Under natural circum- stances their success rate is low, but a colony from which adults have been flushed is "easy pickings." Plundering gulls may walk ahead of human intruders, pecking holes into eggs, or they may fly off with eggs to eat elsewhere (Anderson and Keith 1980). Gulls calling overhead attract more gulls and add to the panic of the colony (Anderson and Keith 1980). Western Gulls are formidable predators. They will consume young chicks whole, including chicks of their own species, and will even attack large 3 to 4 week old pelican chicks to obtain regurgitations or will remove the eyes, uropygial glands, and entrails, causing death (Anderson and Keith 1980). Incubation of eggs and chicks is a means of maintaining an optimum temperature for rapid development. Parents sit on and turn eggs to warm them and will shade eggs and chicks from the sun to keep them from overheating. If parent birds are kept off their nests for a long enough period of time, death of the young from hyper- thermia (overheating) or hypothermia (over- coohng) can occur. Shorter periods of neglect can extend the incubating time required for hatching. The most damaging type of human distur- bance is physical alteration of habitat, since its effects are longterm, and in most cases irreversible. Whaler Island (325 045) near the Oregon border is now part of the Crescent City breakwater and is no longer used by nesting seabirds. Osborne (1972) estimates from historical records that 20,000 storm-petrels (Leach's and Fork-tailed Storm-Petrels), along with Western Gulls, Pigeon Guillemots, and Black Oystercatchers, nested on Whaler Island. Loss of this nesting island may have substantially reduced the number of nesting Leach's and Fork -tailed Storm-Petrels in California. Several seabird species nest in burrows dug into the ground. No one should walk on these burrow areas since they can easily collapse under the weight of a person. Birds may then abandon the burrow. Burrow destruction can also accelerate the serious problem of soil erosion from offshore rocks. Most islands along the California coast were once part of the mainland and soil is primarily or entirely a remant from before the islands broke away. In California, burrow nesting species are: Black, Leach's, Fork-tailed, and Ashy Storm- Petrels, Xantus'Murrelets,Cassin'sand Rhinoceros Auklets, Tufted Puffins, and, in some instances. Pigeon Guillemots. Of these, Rhinoceros Auklets, Tufted Puffins, and Black and Fork -tailed Storm- Petrels are present only in very low numbers. None of these species' California populations exceed 400 birds, and none of these species is present at more than 14 sites in the state. While Cassin's Auklets and Leach's and Ashy Storm- Petrels are present in greater numbers in California, they are also limited to very few nesting loca- tions. Any disturbance to burrow-nesting species would be particularly unfortunate. Whaler Island (325 045) was an important seabird colony until the island was quarried and a breakwater was constructed. Few seabirds nest there now. Photo by Art Sowls SPACE SHUTTLE The following account is drawn largely from Potential impact of space shuttle sonic booms on the biota of the California Channel Islands: literature review and problem analysis (Evans et al. 1979). Channel Island seabird populations may be subjected to a new disturbance during the 1980's. The U.S. Government has selected Vandenberg Air Force Base (VAFB), just north of Point Conception, as launch site for the Space Shuttle. Most of these launches will be directed west over the open Pacific, but approximately six launches planned for polar orbit will pass directly over the Channel Islands. These launches will produce sonic boom pressure waves of up to 30 pounds per square foot (psf), considerably greater than the 2.0 to 2.5 psf produced by aircraft sonic booms. Depending on weather and other factors, sonic booms produced by the Space Shuttle will be at maximum intensity over San Miguel Island (Figure 1). Areas south and east of San Miguel Island will be subjected to intense, though less potentially devastating sound pressures. In addi- tion, all of the estimated 129 Space Shuttle re- entries will pass directly over the Channel Islands. Sonic booms from these flights will be similar to those from military aircraft, and 18 per year are • SAN LUISOBISI>0 Zont of maximum foufid intarattv 30 pif \/ LOS ANGELES SAN CLEMENTE IS, GROUNDTRACK Figure 1. Predicted lines of maximum sonic boom pressures in pounds per square foot (psf) at sea level resulting from Space Shuttle launches into polar orbit from Vandenberg Air Force Base (modified from U.S. Air Force, 1978. Final Environmental Impact Statement, Space Shuttle Program, Vandenberg Air Force Base, California). scheduled. These sonic booms may pose several potential dangers to seabirds: 1) High sonic boom pressures, particularly those from launches, could physically damage birds regardless of the time of year. 2) Both surface nesting and burrow or crevice nesting seabirds may desert eggs and young or fail to initiate nesting because of sonic booms. 3) Death of eggs and chicks will probably occur if sonic booms cause panic flights by adults. This result would be similar to that already discussed in the section "Human Distur- bance." 4) The nests of both burrow-nesting and cUff-nesting seabirds could be damaged or destroyed. An underground nuclear blast in Colorado reduced local raptor reproduction by 20 percent when cliffs crumbled and crushed eggs in two of nine nests (Stahlecker and Alldredge 1976). Sound pressures from the Space Shuttle sonic booms may produce a similar effect. Sonic booms in Arizona reportedly have caused geological damage (Graham 1969). Subterranean - nesting species would be particularly vulnerable to the shifting of rocks and soils. METHODS Information compiled in this catalog comes from four primary sources. The U.S. Fish and Wildlife Service (this study) conducted surveys of seabirds in 1979 and 1980 along the California coast from Point Conception to the Oregon border. An initial survey of this part of the coast was conducted in 1969 and 1970 by Osborne and Reynolds (1971), and their data still provide the best population estimates for some species at some sites. Data for the Channel Islands and the coast south of Point Conception come primarily from another BLM-sponsored oil lease study conducted from 1974 to 1977 by Hunt et al. (1979) and the California Department of Fish and Game. Information for the Farallon Islands has been collected over the past ten years by staff members of the Point Reyes Bird Observatory. Other sources are listed in the references section and in colony tables. All persons known to have gathered recent data compiled in this catalog are listed on the title page under "Contributors". Inherent in any collection of data from different sources is variability in methods. No attempt has been made to enumerate all techniques used to collect data presented in this catalog. Instead we refer readers to the appropriate references from which we obtained population estimates listed in this catalog (After each line of data in the Maps and Tables section, we reference the source from which we obtained the inform- ation). A detailed account of the techniques we used during our 1979 and 1980 surveys is presented below. We conducted seabird surveys from Point Conception to the Oregon border from mid-May to mid -August, 1979, and from mid-May to late August, 1980. Adequate coverage of such a long stretch of coastUne required two teams of two observers each with a vehicle, an inflatable boat, and two outboard engines. In 1980, a fifth observer was added to the team. Surveys were concentrated during the peak of the nesting season, from late May to late July. Surveys of surface-nesting seabirds completed earlier in May when seabirds began nesting were repeated later in the season to determine the maximum breeding population. We concentrated our 1979 surveys on conspicuous, diurnal, surface-nesting species such as Brandt's Cormorants, Pelagic Cormorants, Western Gulls, Common Murres, and Pigeon Guillemots. In 1980, we divided our time equally between censusing diurnal surface-nesting seabirds and censusing nocturnal burrowing species such as storm-petrels and Rhinocerps Auklets. All sections of coastline with likely seabird nesting habitat were surveyed by boat one or more times. Least Terns nesting in bays and on beaches were not counted, since their populations are surveyed annually by the California Depart- ment of Fish and Game. We did not attempt to census Snowy Plovers (Charadrius alexandrinus), Clapper Rails (Ralliis longirostris), American Avocets (Recurvirostra americana), Black-necked Stilts ( Himantopus mexicanus), or some of the other species mentioned by Varoujean (1979) in his catalog of seabird colonies of the Pacific States, which was completed from available Uterature before our surveys were made. Counts were made from inflatable boats using 7X binoculars or the unaided eye. We found that binoculars with a wide-angle field of view were far superior to normal binoculars when counting from boats. Whenever possible, direct counts of nests and individual birds were made. Usually, the boat was slowed or stopped and both observers counted birds or nests at the same colony or section of cliff. Counts were often repeated to ensure accuracy. Except for the Farallon Islands (429 012) and Redding Rock (325 013), all islands and offshore rocks north of Point Conception are within one kilometer of the mainland. Counts of seabirds on offshore rocks, islands, and mainland cliffs were often made from shore promontories. Generally, these counts underestimated popu- lations since only the landward sides of colonies were visible. In many instances, our population figures for a particular colony are derived from a combination of different survey techniques, which may have included boat surveys, aerial photography, counts from the mainland, and observations made directly on an island after landing. Landings were made on islands and rocks whenever possible, except at colonies of Brandt's Comiorants and Common Murres, which are especially sensitive to disturbance. When we landed on an island, we counted cormorant and gull nests and searched for burrows of storm- petrels, auklets, and puffins. Island visits were as brief as possible to minimize disturbance. Counts made from boats, the mainland, and the islands themselves were the principal methods used to census Double-crested Cormorants, Pelagic Cormorants, Western Gulls, Black Oyster- catchers, Pigeon Guillemots, Marbled Murrelets, Rhinoceros Auklets, Tufted Puffins, and, to a lesser extent, Brandt's Cormorants. Most of our surveys were conducted in 1979. In 1980 we attempted to refine estimates made at locations where surveys were hampered by poor weather conditions the previous year. Also, many sites which were accurately surveyed in 1979 were resurveyed in 1980 to determine whether any population changes had occurred. Cormorants and gulls build conspicuous nests and are therefore the easiest species to census. Since their nests were directly counted, our population estimates for these species are the most reliable. Most surveys for Pelagic Cormo- rants and Western Gulls were made from a boat, often very close to shore. Our counts of Double- crested and Brandt's Cormorants and Western Gulls were sometimes hampered by our inability to see the tops of islands, the preferred nesting habitat for these species. We circumvented this problem by making counts from the mainland where possible, or by taking aerial photographs. We counted and noted the locations of all Black Oystercatchers, Marbled Murrelets, Pigeon Guillemots, Rliinoceros Auklets, and Tufted Puffins seen during our surveys. Nests of these species are either difficult to find or, in the case of burrowing species, difficult to identify with certainty. Therefore counts of individual birds and extrapolation from these counts were our best survey method. Black Oystercatchers were counted during nearshore surveys but in 1979 poor weather hampered our efforts in some locations. Better weather in 1980 allowed us to re-survey selected portions of the coastline and improve our census data. Because nests of this species are difficult to find, the breeding status of many Black Oyster- catchers was impossible to determine. Estimates of populations were usually based on the presence and behavior of birds rather than counts of nests. Some non-breeding oystercatchers were probably included in our counts and may have inflated population estimates for some regions. Fre- quently, however, sections of coastline with poor habitat for other seabirds were by-passed, even if some habitat looked promising for Black Oyster- catchers. For this reason, and because oyster- catchers were sometimes hard to see among the confusion of reefs, rocks, and breakers, we believe our estimates of Black Oystercatcher populations in California are conservative. Marbled Murrelets were counted opportu- nistically in a narrow strip offshore of the coast. The distances of these counts from shore varied, depending on the nature of the coast, but never exceeded one kilometer. The most critical factors influencing our counts of Marbled Murrelets were sea conditions and time of year. Our counts were made from small inflatable boats, so we probably overlooked some birds on the water in all but the flattest seas. The best censuses of Marbled Murrelets can probably be made in spring when both members of a breeding pair are on the water offshore of coastal forests. Our surveys, however, were usually conducted later in the year. In addition, our census strips were of necessity narrow and this probably resulted in many missed birds. Although our surveys of Marbled Murrelets have provided few data with which future compar- isons can be made, we feel they reflect the species' breeding distribution in the state. Rhinoceros Auklets and Tufted Puffins were frequently seen standing near and entering burrows in the early morning. Time of day is an important factor when censusing these birds, since they are seldom seen at their colonies in late morning and afternoon. We tried to locate eggs and chicks of Rhinoceros Auklets and Tufted Puffins at several sites where we observed these birds, but only at Prince Island (325 003) were we successful. For the other sites in our study area, we based our population estimates on the number of birds in breeding plumage on or near the colonies in 1979 or 1980. For some colonies that had been previously intensively surveyed, we relied on estimates in the Uterature. Pigeon Guillemots are some of the most difficult of California seabirds to census. Finding Pigeon Guillemot nests during brief surveys of the rugged habitat where they usually nest is nearly impossible. Also, numbers of birds around a colony fluctuate greatly depending on the stage of nesting and time of day. Distinguishing breeders from non-breeders is impossible in most cases, so our numbers reflect the total number of guillemots at a colony rather than the number of breeding birds. We found that Pigeon Guillemots are present in large numbers around colonies in the early morning but nearly disappear by mid to late afternoon. Once incubation begins one member of each pair is probably always absent from view. The best time to census this species is therefore in the early morning, before the egg laying season, when both members of a breeding pair are on the water near the colony. Nettleship (1976) concluded that this is the best time to census populations of the similar Black Guillemot (Cepphus grylle) in arctic and eastern Canada. Surveying Pigeon Guillemots later in the day will result in underestimation of numbers or even failure to detect entire colonies. Most of our surveys could not be conducted at this optimum time, so guillemot estimates which appear in this catalog are based not only on the numbers of birds seen, but have been modified to reflect the influences of time of day, stage of nesting, and quality of habitat. These adjusted numbers, we feel, provide the most realistic estimates of the populations at each site, but they may be higher or lower than actual guillemot numbers. Although our population estimates are almost always many times higher than those made during previous surveys (1,285 percent higher for the entire study area), we still feel they are conservative. Differences in survey techniques and more com- plete coverage of the coast are likely to account for our higher numbers. Aerial surveys were our best means of censusing Brandt's Cormorants and Common Murres. In 1 979, we conducted nine aerial surveys in order to cover the coast from Point Conception Jay Nelson and Bill Rodstrom censusing cliff nesting seabirds from a small boat at False Cape Rocks (325 040). Photo by Art Sowls to the Oregon border. Three 1979 surveys were flown from a high-wing Cessna 182 or 210 and the remaining six were flown in U.S. Coast Guard helicopters. In 1980 we conducted five aerial surveys. Four of these were made in a high-wing Cessna 172, and one was flown from a U.S. Coast Guard helicopter. Photographs of seabird colonies were taken either through the open window of a plane or open door of a helicopter. Both color shdes (ASA 64, 200, and 400) and black-and-white film (ASA 132 and 400) were exposed in a 35-millimeter camera equipped with either a 70- to 2 10- millimeter zoom lens or a 300-millimeter lens. Flight altitudes varied, but most photographs were taken from an altitude between 150 and 250 meters. We were careful not to flush nesting seabirds or marine mammals by flying too low, and we are satisfied that we caused no disturbances during our aerial surveys. Seabirds flush readily from their nests when "buzzed" by low-flying aircraft, therefore it is imperative to fly high enough to avoid disturbing them. For the study area from Point Conception to the Oregon border, we recommend a flight altitude of 200 meters or higher. Common Murres in coastal California nest primarily on the flat tops of islands and, possibly, excluding murres nesting on the Farallon Islands, appear somewhat accustomed to low-flying aircraft. Murres in other regions also frequently nest on cliff faces where more care is needed to avoid flushing birds. HeUcopters are more disturbing to birds than fixed-wing aircraft, and should maintain a higher altitude. Telephoto lenses, especially zoom lenses in the 70- to iOO-milHmeter range, are needed to photograph seabird colonies well enough to make accurate counts later from the photos. Rapid shutter speeds of 1/1,000 second or 1/500 second lare important to dampen vibrations. We usually jused high speed color slide film because it enabled 'us to shoot at rapid shutter speeds even on cloudy days. j Most counts of Brandt's Cormorants and ^Common Murres were made from projected sUdes. In the case of Brandt's Cormorants, we counted individual nests and determined the number of breeding birds by multiplying the number of nests by two. Brandt's Cormorant nests are conspicuous and easy to count from aerial photographs. Our estimates for this species are probably as accurate as any estimates included in this catalog. Numbers of Common Murres were estimated either by counting individual birds on slides or by blocking off groups of lO's, 50's, or lOO's, depending on the sizes of colonies and the quality of our photographs. Time of day and of year influence the number of Common Murres at a colony. The greatest numbers of murres are seen in early morning, before the egg-laying season. Both members of each breeding pair, as well as non- breeding birds, are presumably present on the colony at this time. Later in the season, during the incubation and nestling stages of nesting, the number of murres on a colony at any one time decreases because one member of each pair is frequently at sea. Most of our surveys were flown during the incubation and nestling stages, near mid-day. A correction factor must be added to the murre count to account for this variability in colony attendance. Addition of a correction factor to our counts of murres from photographs should result in an adjusted estimate of the breeding population which is more representative than the straight count from the photographs. We used a factor of two-thirds, as proposed by Ainley (1976). A factor of two-thirds implies that fewer than half of the birds are away from the colony at the time of a survey, an assumption which we feel is reasonable. To obtain the adjusted total, we multiplied the count obtained from the photographs by 1.67. Our estimates of murre numbers included in this catalog are only the adjusted totals. The actual numbers of murres counted from slides, which may be the most useful numbers for later historical compari- sons, can b» obtained by dividing the number listed in this catalog by 1 .67. i is Brandt's Cormorants and Common Murres were censused primarily by counts made from aerial photographs. Here, Brandt's Cormorant nests are shown at Piedras Blancas (477 00 7). Photo by Jay Nelson 10 We were unable to distinguish between breeding and non-breeding Common Murres on the photographs. Our Common Murre estimates are actually the numbers of birds at a colony rather than the numbers of breeding birds. Common Murres are extremely difficult to census and our estimates of their populations are probably the crudest of all estimates in the catalog. These birds pack densely on islands and it is often impossible to distinguish between individuals, even on high-quality photographs. Comparison of our numbers with those obtained in future surveys will be difficult, but direct visual comparisons of photographs could easily show whether the extent and density of a colony has markedly changed . To make comparisons simpler, we have archived data and photographs at several different sites (see Appendix A). Storm-petrels and Cassin's Auklets are nocturnal and difficult to census. We made no attempts to census colonies of nocturnal seabirds which we knew existed on Castle Rock (325 006), Green Rock (325 020), and Little River Rock (325 035), but instead relied on population estimates in the literature. Other colonies of nocturnal birds in our study area which we censused were either small in magnitude or small in area and did not warrant intensive survey efforts such as establishing sample plots and determining the ratio of active to inactive burrows. To obtain more refined data on these sites would have caused more disturbance than we felt was justified. Besides searching many islands for storm- petrel and Cassin's Auklet colonies during the day, we made overnight surveys one or more times on Prince Island (325 003), Flatiron Rock (325 023), Pewetole Island, Button Rock (325 054), Goat Rock (379 006), an island at Van Damme Cove (379 027), and Fish Rocks (404 003). We conducted searches at night for nesting storm-petrels and auklets, and on all but Pewetole Island, Flatiron Rock, and Goat Rock erected mistnets to catch nocturnal birds. We caught and banded 174 Leach's Storm-Petrels on Prince Island, Button Rock, and Fish Rocks combined. Our population estimates for several storm-petrel colonies were based on one or more of the following: 1) thenumberanddensity of burrows, 2) the number of birds seen and heard on the island at night, 3) the number of birds captured and banded, and 4) the number of birds recaptured. We discuss our population estimates for storm- petrels at each site more fully in the species accounts. We offer no new estimates of Cassin's Auklet numbers in the catalog. This catalog includes the best information available for all seabird colonies along the coast of Cahfomia, but the information varies in quaUty from species to species and from site to site. We have devised a data quality code, described below, as an attempt to rate our data by its quality. A data quahty code number follows each of our population estimates in the maps and tables section. Data Quality Code I. Total count of all nests (number of nests X 2 = number of breeding birds). Few if any errors were made in these counts. Any changes in number of breeding birds from year to year can probably be detected. II. Count of nests. Because of omission or misidentification of nests, counts may be slightly higher or lower than actual bird numbers. Small or moderate changes in number of breeding birds from year to year can probably be detected. III. An estimate of the size of a breeding population based on counts of nests and birds and on estimation of the amount of available nesting habitat. Census techniques vary considerably among species. Only large changes in populations from year to year can probably be detected. DISCUSSION Populations containing nearly 700,000 sea- birds, representing 23 species, are discussed in this catalog. All major and most minor seabird colonies along the Cahfomia coast have probably been, identified, and present data seem adequate to evaluate the importance of even small sections of coastline to breeding birds. Unfortunately, sufficient historical data do not exist to evaluate population changes or trends that may have occurred or are occurring along much of the Cahfomia coast. Only on the Farallon Islands (429 012), Santa Barbara Island (524 008), Anacapa Island (502 007), and at Least Tem colonies in southem Cahfomia have long-term studies been initiated. Although Cahfomia's breeding marine avi- 11 fauna is diverse, only a few species make up the majority of this assemblage of seabirds. Common Murres, Brandt's Cormorants, Cassin's Auklets, and Western Gulls compose almost 90 percent of the California population (Figure 2). A dispro- portionately large percentage of this population breeds at only a few locations in the state. Two regions, the Farallon Islands and the north coast of California from Cape Mendocino to the Oregon border, contain the largest number of breeding seabirds (Figure 3). The Farallon Islands are extremely important. Large portions of the state's breeding populations of Ashy Storm-Petrels, Brandt's Cormorants, Western Gulls, Common Murres, Pigeon Guillemots, Cassin's Auklets, Rhinoceros Auklets, and Tufted Puffins breed on these islands (Figure 4). The coastUne north of Cape Mendocino contains more breeding seabirds than the Farallon Islands although no single site there approaches the Farallones in number of birds. Large portions of the state's breeding population of Fork-tailed Storm-Petrels, Leach's Storm-Petrels, Double- crested Cormorants, Common Murres, Rhinoceros Auklets, and Tufted Puffins inhabit this coast. Castle Rock (325 006), the second-largest seabird colony in the state, is found in this stretch of coastline. The Channel Islands are particularly note- worthy since the entire California breeding populations of Black Storm-Petrels, Brown Pelicans, and Xantus' Murrelets nest there. The Figure 2. Populationsof breeding seabirds and per- cents of total aggregate population in California. Leach's Storni-Petrel 1 8,304 (3%) Pelagic Cormorant 15,870(2%) Pigeon Guillemot 14,724 (l'A\ Foik-tailed Storm-Petrel Ashy Storm-Petrel Black Storm-Petrel Brown Pelican Double-crested Cormorant Black Oystercatcher Forster's Tern Least Tern Elegant Tern Caspian Tern Black Skimmer Marbled Murrelet Xantus' Murrelet Rhinoceros Auklet Tufted Puffin * coastal population only. (4%) 12 more sub-tropical seabird community of the Channel Islands, although containing fewer breeding seabirds than the Farallon Islands and northern Cahfomia, is of no less importance. Six of the 23 species discussed in this catalog are widespread along much of the California coast. Of the six, the Black Oystercatcher is the most widely distributed, despite an estimated breeding population of only 1,000 birds. This distribution reflects the abundance of this species' preferred nesting habitat in California. The Black Oystercatcher's small population size, however, is perhaps related to its tendency to nest as isolated pairs on offshore rocks and inaccessible stretches of the California coastline. The distributions of Pelagic Cormorants and Pigeon Guillemots are also relatively uniform, in part because their nesting habitat is abundant in this state (Figure 4). Pelagic Cormorants are most numerous between Cape Mendocino and San Francisco, an area possessing long stretches of vertical cliffs. Pigeon Guillemots attain their greatest abundance in central California, south of San Francisco, including the Farallon Islands, but large colonies are also found at many locations north of Point Conception. Both Brandt's Cormorants and Western Gulls are widely distri- buted throughout Cahfornia but extremely large concentrations of each exist on the Farallon Islands (Figure 4). Common Murres are found throughout much of central and northern Cahfomia although they are most abundant in Figure 3. Percentage of breeding seabirds along the California coast. Circle size is directly pro- portional to numbers of birds. 13 Fork-tailed Storm-Petrel Calilornia Colonies Catalog Total 310 birds • ■ colony sites o K. lormer sites Leach's Storm-Petrel California Colonies Ashy Storm-Petrel Calilornia Colonies Black Storm-Petrel California Colonies Catalog Total 150 birds • ■ colony sites Brown Pelican California Colonies Catalog Total 2.690 birds colony sites former sites Brandt's Cormorant California Colonies Catalog Total 64,210 birds • • colony sites Double-crested Cormorant California Colonies Catalog Total 1,884 birds' • ■ colony sites Pelagic Cormorant California Colonies Catalog Total 15,870 birds • • colony sites * coastal population only. Black Oystercatcher California Population Catalog Total 704 birds • « nest sites Figure 4. Percentages of the California breeding population of seventeen species, of seabirds for 14 Western Gull Calilornia Colonies Catalog Total 50,930 birds • = colony sites Common Murre Calilornia Colonies Catalog Total 363,154 birds • ■ colony sites = former sites 16% 3%/ "^ 8%\ 20%] f^ ;-=^ 8% 1^ 17% (^ 1%\ Pigeon Guillemot California Colonies Catalog Total 14,724 birds a colony sites 14% 1% Marbled Murrelet California Population Estimate 2,000 birds Xantus' Murrelet California Colonies Catalog Total 3,500 birds • ■ colony sites Offshore Sighting ■ =high feS 'low Cassin's Auklet California Colonies Catalog Total 131,170 birds • - colony sites Rhinoceros Auklet California Colonies Catalog Total 362 birds • * colony sites Tufted Puffin X = present, less than 1% California Colonies ten sections of the coast and the Farallon Islands. K northern California. Twelve of the 23 species discussed in this catalog reach either the northern or southern limits of their breeding ranges within California. Elegant Terns breed only as far north as San Diego Bay. Black Storm-Petrels, Brown Pehcans and Xantus' Murrelets breed as far north as the Channel Islands, although they are much more abundant farther south. The breeding range of Ashy Storm-Petrels is restricted to coasts between northern Baja California, Mexico, and Marin County in northern California. Fork-tailed Storm-Petrels, Pelagic Cormorants, Common Murres, Pigeon Guillemots, Marbled Murrelets, Rhinoceros Auklets, and Tufted Puffins are all cool water species and reach the southern limits of their breeding range within Cahfomia. Pelagic Cormorants and Pigeon Guillemots breed as far south as the northern Channel Islands, as did Common Murres and Tufted Puffins until the early part of this century. Breeding Common Murres and Tufted Puffins can now be found only as far south as Monterey County in central California. Marbled Murrelets probably breed no farther south than the coastal forests in Santa Cruz County, although they have been observed as far south as Point Sal during the breeding season. Probably the southernmost breeding location of the Rhinoceros Auklet is at Point Arguello (501 Oil). The southern range limit of breeding Fork-tailed Storm-Petrels lies in the islands of Trinidad Bay. Point Conception and the northern Channel Islands are considered the boundary zone between warm and cold waters in California. There is no clean division of water masses in this area, however. The region is, instead, a complex oceanographic zone. The principal oceanographic components are a cold southerly-flowing offshore current (the California Current), a cold northerly- flowing offshoot of the Cahfornia Current (the Southern Cahfomia Countercurrent), and a cold southerly-flowing inshore current (the Southern California Coastal Current), all of which are seplarated in part by bodies of warm water. At this complex junction of water masses, Black Storm-Petrels, Brown Pehcans, Pelagic Cormorants, Pigeon Guillemots, and Xantus' Murrelets reach the limits of their breeding ranges. Populations of seabirds living at the edges of their breeding ranges are often small. This is best illustrated in California by Fork -tailed Storm- Petrels, Black Storm-Petrels, and Tufted Puffins. These populations may be particularly susceptible to changing environmental conditions and distur- bance. If local extinction should occur, as it has in the case of the Tufted Puffin in the Channel Islands, re-establishment could take a very long time. Breeding activity of seabirds in Cahfomia is related to the hydrographic cycle by its synchrony with a period of upwelhng that usually begins in March. During this period, strong northwest winds develop and surface waters along the coast move southerly and offshore. Cold, high- salinity waters upwell along the coast to replace surface waters moving away from the shore. Once these cold, nutrient-rich waters reach the photosynthetic zone, they trigger a phytoplankton bloom which in turn triggers an increase first of 'zooplankton and later of fish and squid. Bolin and Abbot (1963) have shown that in Monterey Bay, phytoplankton begins increasing in late January and peaks in June. Seabirds of all species in Cahfomia concentrate their breeding activites from as early as late winter through June and early July, coinciding with the time of peak plankton production. Productivity of plankton along the coast decreases in late summer and early fall during the oceanic period of the hydrographic cycle (Bolin and Abbot 1963). At this time of year, the strong northwest winds abate. Cold, surface waters sink and are replaced by warm, low- nutrient waters from offshore. Lack of food at this time of year may help explain the cessation of breeding activity and the occurence of periodic die-offs of young birds, especially Common Murres. The intensity and duration of the upwelhng period may influence the number of birds breeding and their productivity. This may explain the decreases in numbers of Brandt's Cormorants which we observed at many sites in California in 1980 from the numbers we observed in 1979, which was apparently a banner year for seabirds in Cahfomia. During the fall and winter, warm, nutrient- depleted waters intrude into the Califomia coastal zone. These coastal waters move slowly northward, pushed by predominantly southerly winds to form a countercurrent (Schwartzlose 1963). If, during the following period of upwelhng, north- west winds are not strong and persistent, upwelhng will be weak. Water temperatures will be higher, plankton productivity lower, and the numbers of breeding seabirds and their productivity will decline. Fluctuations in these oceanic conditions occur yearly, so variation in the number of breeding seabirds and their productivity is 16 Pt. Reyes' \N FRANCISC0i The timing and success of breeding of many \ California seabirds is related to the upwellingi \of cold, nutrient-rich water. This enhanced \ ] infrared satellite photograph shows cold water] \ masses (lighter in color) upwelling along the I coast, particularly near prominent points. Photo compliments ofNOAA common. More prolonged changes in climate can also influence breeding populations of seabirds. Cassin's Auklets, now the most abundant seabirds on the Farallon Islands, were rare on those islands in the mid-1 800's (Ainley and Lewis 1974). These auklets are cold water birds found from the Pacific coast of Baja California, Mexico, north to the Gulf of Alaska and the Aleutian Islands. In Cahfomia, the breeding period of this species coincides with the period of upwelling of cold, nutrient-rich waters when zooplankton is most abundant. According to Hubbs (1948), the ocean climate from 1853 to the 1870's was dominated by a northward intrusion of warm water. Ainley and Lewis (1974) believe this northward intrusion of warm water extended as far north as the San Francisco-Farallones region and may explain the scarcity of Cassin's Auklets on the Farallon Islands during that time. Additional evidence of this was found during two other warm water periods in recent years when Cassin's Auklet productivity on the Farallon Islands was signif- icantly lower than in cold water years (Ainley and Lewis 1974). Gradual changes in seabird populations may also occur in response to the gradual degradation and formation of nesting habitat. Many islands and rocks along the California coast are eroding away. During this process, the habitat changes and it may become more suitable to some species and less suitable to others. For example, younger islands with deep soil layers are preferred by burrowing species such as storm-petrels, Cassin's Auklets, Rhinoceros Auklets, and Tufted Puffins. As the soil erodes away, islands become less suitable to these species. Cormorants may colonize the barer regions of the island and speed soil and vegetation loss. Once an island is stripped of soil and vegetation it may be suitable only for cormorants, murres, and, to a lesser extent, Western Gulls. Examples of nesting islands in different stages of their evolution are evident up and down the California coast. Point Sur, at the north end of Big Sur, and Trinidad Head in northern California are obvious islands-in-the-making, although they are still attached to the mainland. Pewetole Island, north of Trinidad Head, is a forested island recently cut off from the mainland, still accessible to predator^ \mi tide, and at the present time inhabited onty by Black Oyster- catchers. This island appears to offer excellent petrel habitat and could become an important colony once the channel between it and the mainland deepens. Little River Rock (325 035) is a treeless but heavily vegetated island in northern California, accessible to humans by wading at low tide. Little River Rock is the largest storm-petrel colony in California but it has recently been colonized by Double-crested Cormorants which are degrading the habitat for burrowing species (Harris pers. comm.). Flatiron Rock (325 023) is an almost bare island in northern California presently inhabited by large numbers of Common Murres, Brandt's Cormorants, Western Gulls, and a very few Pigeon Guillemots and Tufted Puffins. Clay (unpubl. field notes) in 1911 reported Tufted Puffins as numerous there and also found nests of Pigeon Guillemots, Cassin's Auklets, and Leach's Storm- Petrels. We found the burrow nesting habitat to be poor in quality and used by few birds during our visits to the island in 1980. These examples show a continuum in the evolution of seabird nesting habitat from future islands, to new islands with deep soil, to older islands with less soil, suitable only for surface nesting seabirds, and finally to wave-washed rocks unsuitable for nesting. Seabirds themselves can be active agents in the evolution of nesting habitat. Pelicans, cormo- rants and gulls remove plants for nest building and their excrement sometimes kills vegetation. Burrowing species contribute to the destruction of their own nesting habitat by digging burrows and removing soil. Puffin Island, in the Chamisso Island National Wildlife Refuge in Alaska, is a vivid example. There, a burrowing population of Homed Puffins has created long, deep furrows in the sod where burrows have collapsed, accelerating recession of the vegetative cover from the nesting area and hastening the removal of soil through erosion (DeGange and Sowls unpubl. data). Seabird numbers and productivity vary naturally from year to year and also over longer periods of time. Man's activites have in the past had largely adverse effects on California's seabirds. Additional conflicts in the future are likely, but still avoidable. We hope that planners will carefully consider the welfare of seabirds when making coastal policy decisions. To this end, the catalog of California seabird colonies will be useful. Seabird populations in this state can flourish indefinitely, as long as they can satisfy their basic needs - food, sufficient habitat, a clean environment, and freedom from disturbance. In this sense, "management" of seabirds should be directed towards meeting these needs. 18 Common Murres at Point Reyes (429 001). How many? Our count is at bottom of page 21. Photo by Anthony R. DeGange 19 Fork-tailed Storm -Petrel (Oceanodroma furcata) — ^is-'t World Breeding Range Fork-tailed Stomi-Petrels are small seabirds often found far from land over the open ocean. They usually feed at the ocean's surface on plankton but are known to follow fishing vessels and to feed on scraps and fishing offal. Although the species occurs in California, its center of abundance appears to be the Aleutian Islands and the Gulf of Alaska (Sowls et al. 1978). Fork-tailed Storm-Petrels breed on offshore rocks and islands safe from mainland predators. Throughout their range they nest in both rocky crevices and, to a lesser extent, burrows in soil. To avoid diurnal predators, colony activity occurs during the darkest hours of the night. Adults mate, exchange incubation and brooding duties, and feed chicks only during the night, remaining in the burrow or returning to offshore waters by day. For this reason Fork-tailed Storm- Petrels are rarely seen at the breeding colonies during the day. Their nocturnal habits make detection of colonies difficult and estimation of populations imprecise. CALIFORNIA COLONIES Fork-tailed Storm-Petrels have been iden- tified at six sites in California, all north of Eureka (Harris 1974, this study). The largest of these. Little River Rock (325 035), is inhabited by approximately 200 birds. The population at Castle Rock (325 006) is estimated at 100 birds (Osborne 1972), and the other four colonies together probably contain fewer than 100 birds (Harris 1974, present study). All major colonies of Fork-tailed Storm-Petrels in California have probably been found, but additional small colonies may still exist. HISTORICAL STATUS AND VULNERABILITY Published data indicate that since the 1930's, Fork-tailed Storm-Petrels have disappeared from three California sites and been found at an additional four sites. A major colony of storm- petrels was extirpated from Whaler Island (325 045), Del Norte County, after construc- tion of a breakwater to the island in the 1930's (Osborne 1972). Clay and Dawson found Fork-tailed Storm-Petrels nesting on Blank Rock (325 023) in 1916 (Dawson 1923) but this species no longer breeds there (Osborne 1972). Soil erosion probably led to their disappearance from these two islands. Fork-tailed Storm-Petrels have recently been found on Little River Rock (325 035), Prisoner Rock (325 027), and Tolowa Rocks (325 007) (Osborne 1972, Harris 1974, this study). These recent discoveries probably reflect a more thorough search for nests rather than an increase in population and colonization of new sites. Fork-tailed Storm-Petrels readily desert their nests if disturbed by humans during incuba- tion or while parents are brooding recently hatched chicks. Evidence from studies of an Alaskan 20 100% J California Colonies zt Catalog Total -I 310 birds: N. • = colony sites > r» \v 0 = former sites ^S ^ \^ I. \v ( \^^ \ \. T- ^_J Breeding Population. / Breeding Chronology Northam California Incubation Period •37-68 days Nwtling Py iod ■ <6 dayi (3.4.17,24,10) Contfil Cilifomia NotBfMdint' ItuaieTS in parentheses correspond to the references from vhlch ve obtained the data. Southtm California ' Not Braiding; Jan. I Feb. | Mar. | Apr. | May I Juna | July I Aug. | Sep. | Oct. | Nov. | Dae. population shows that extremely unfavorable weather conditions or insufficient food supplies will cause parents to temporarily abandon eggs and chicks (Boersma et al. 1980). Such temporary abandonment of nests reduces viability of eggs, causes death among chicks, and lengthens the breeding season (Boersma and Wheelwright 1979, Boersma etal. 1980). Fork-tailed Storm-Petrels are most vulner- able to oil pollution during the summer months when their movements are restricted to nearshore areas by breeding activities (Lensink et al. 1978, Wiens et al. 1978.) While these petrels generally feed in waters over the continental shelf (Lensink et al. 1978), they are usually uncommon in the coastal zone of CaUfomia and become more abundant only during years of unreasonably cold water (Ainley 1976). Considering this species' small population size, restricted number of breeding sites, and low reproductive potential, any major disturbances to their breeding colonies could be disastrous to the CaUfomia populations. Fork-tailed Storm-Petrels, like allprocellariiformes. have a tube-nose. Our count for photograph, page 19 : Common Murre = 4,000; Brandt's Cormorant = 1 21 Leach's Storm-Petrel (Oceanodroma leucorhoa) Leach's Storm-Petrels are the most abundant of the storm-petrels breeding in California and are probably the most pelagic of the four species. Although breeding colonies are confined to the northern hemisphere, wintering birds range south to tropical waters in both the Pacific and Atlantic Oceans (Pahner 1962). Like all storm-petrels, Leach's Storm-Petrels are nocturnal on the breeding colonies, an adaptation which reduces their susceptibiUty to diurnal predators such as gulls. Nests are ususally located in burrows or, less frequently, in rock crevices (Palmer 1962). Leach's Storm-Petrels have a well-developed olfactory system (Bang 1966, Stager 1967) and Grubb (1973, 1974) has suggested that these birds, which often nest in crowded colonies in dense spruce forests, may locate their burrows by odor. Like most seabirds. Leach's Storm-Petrels exhibit relatively long lifespans and low mortality rates for their size. Individuals that survive the hazardous first year of Ufe can live up to 24 years and possibly longer (Graham 1980). Additional references on this well-studied species include Ainley et al. (1974, 1976) AinsUe and Atkinson (1937), Gross (1935), Harris (1974), Huntmgton (1963), Morse and Buchheister (1979), ThrelfaU (1974), and Wilbur (1969). CALIFORNIA COLONIES Leach's Storm-Petrels are known or suspected to breed at 13 sites along the California coastline. While most sites are located in the northern part of the state, recent evidence suggests that small numbers of Leach's Storm-Petrels may also nest in the Channel Islands (Hunt et al. 1979). The largest colony in California is located at Little River Rock (325 035), which has 10,000 birds (Harris 1974). Other major colonies are Castle Rock (325 006) with 5,000 birds, the Farallon Islands (429 012) with 1,400 birds, Trinidad Bay Rocks (325 054) with 1 ,640 birds, and Prisoner Rock (325 027) with 160 birds. Colonies are suspected to exist at Fish Rocks (404 003), Prince Island (325 003), and Tolowa Rocks (325 007), although nests of this species have not been found at these locations. On both Fish Rocks and Prince Island suitable nesting habitat is available and Leach's Storm-Petrels with clearly visible incubation patches have been mist-netted and banded. We are confident that Leach's Storm-Petrels breed at Fish Rocks because of our recapture of banded birds there and the island's isolation from other known Leach's Storm-Petrel colonies. At Prince Island no recaptures of banded birds were made and it is possible that the birds we caught were from nearby colonies at Castle Rock (325 006) and Goat Island, Oregon. At Tolowa Rocks, the less common Fork-tailed Storm-Petrels were found nesting in burrows. Many unexamined burrows were present and it seems likely that Leach's Storm-Petrels nest there. All major colonies of Leach's Storm-Petrels in California have probably been identified, but 22 Percent of California Breeding Population. California Colonies Catalog Total 18,304 birds colony sites former sites Breeding Chronology Northern California Farallon Itlandt Southam California Incubation Psrkxl ■ *2 dayi Nwtliog Period - 66 -70 dayi ew laying (24) •« laying : 1(1) hatching ^fiB •09 layiofl (31) ? -n hatching No data available for Channal Itlandt populations. Chrono/ogy conttructad from datat of aggt ■% • collacted in Lot Coronadot Itlandt of . Maxico. ^ —. fledging MM r 1 tm^am^m^am^^^^mm^^ Jan. I Fab. | Mar, j Apr, j May | June | July | Aug. | Sep. I Oct. | Nov. | D^ additional small colonies may exist on almost any island with suitable habitat. HISTORICAL STATUS AND VULNERABILITY Limited published data suggest that Leach's Storm-Petrels have decUned in number in California since the turn of the century. Breeding colonies were once found on Whaler Island (325 045), Blank Rock (325 024), Flatiron Rock (325 023), and Green Rock (325 020). They have been extirpated from the first three islands and only one dead petrel was found on Green Rock during a survey in 1970 (Osborne, 1972). On Whaler Island, a colony of 20,000 storm-petrels was destroyed after construction of a breakwater to the island in the late 1 930's and the breakwater's subsequent strengthening in the early 1950's. The island was quarried for rock and the intro- duction of rats hastened the colony's demise (Osborne 1972). Storm-petrels on Blank, Flatiron, and Green Rocks may have been reduced in number or eliminated by over-collecting and accelerated soil erosion caused by early egg collectors and by erosion caused by nesting cormorants and murres. Harris (pers. comm.) believes that the recently established breeding population of Double-crested Cormorants on Little River Rock (325 035) is preempting and destroying storm-petrel nesting habitat. This Double-crested Cormorant colony has increased substantially in recent years, from two pairs in 1974 to about 50 pairs in 1980 (Yocom and Harris 1975, this study). Nearby Trinidad Bay Rocks (325 054) may be receiving the petrels displaced from Little River Rock. For example, Button Rock (325 054) had no nesting storm-petrels in 1970 (Osborne 1972), but in 1980 approximately 1,000 Leach's Storm- Petrels were actively breeding there. Nevertheless, the loss of nesting habitat through soil erosion and the displacement of birds by cormorants may be two of the most significant threats to storm- petrels in California. Predators such as River Otters (Lutra canadensis) and Mink (Mustela vison) can also be detrimental to storm-petrel colonies. Osborne (1972) found about 90 dead Leach's Storm Petrels on Prisoner Rock during surveys in 1969, 1970, and 1972 and attributed these losses to mink. In 1980 we observed 45 Leach's Storm- Petrel carcasses on Prisoner Rock and suspect a river otter was the predator. Despite this loss, our estimate of Leach's Storm-Petrels for this colony remains similar to Osborne's. The population of Leach's Storm-Petrels on the Farallon Islands appears relatively stable in size (Ainley and Lewis 1974). Leach's Storm-Petrels are vulnerable to contamination by oil. The period of greatest susceptibility is from February to October when they are most abundant off coastal California. During the winter they are uncommon within 30 kilometers of shore (Ainley 1976) and are unlikely to be affected by coastal oil spills. 23 Ashy Storm-Petrel (Oceanodroma homochroa) World Breeding Range Ashy Storm-Petrels, like other storm-petrels, are diminutive birds well suited to oceanic Ufe. Their breeding range overlaps with that of their close relative, the Leach's Storm-Petrel, but they occupy different feeding niches. The Ashy Storm-Petrel forages in the waters of the California Current, just off the continental shelf, while the Leach's Storm-Petrel feeds over a vast pelagic range (Ainley et al. 1974). Ashy Storm-Petrels and other members of the family Hydrobatidae feed on small inverte- brates and fish caught at the ocean surface. All hydrobatid young are fed a pecuUar smelUng oil which the adults regurgitate. This oil, or "petro- leum," as labelled by Griimell (1897), provides a concentrated energy source for growth of the young and allows adults to carry more food than if they return with whole prey. Ashy Storm-Petrels usually nest in natural rock crevices, although the Farallon Island population uses rock walls and buUding foundations as weU (Ainley et al. 1974). Adults are nocturnal at the colonies and may only return with food every few nights. Foraging trips lasting several days probably allow storm-petrels to feed over a larger range to optimize their effort. The nocturnal habits of Ashy Storm-Petrels may serve to reduce predation by normally diurnal Western Gulls. On the Farallon Islands, Ainley et al. (1974) found "that only one percent of the storm-petrels were taken by Western Gulls each year. In addition, Ashy Storm-Petrel young fledge late in the year after many of the gulls have left the Farallon Islands and by this strategy may avoid a potentially serious post-fledging mortaUty. CALIFORNIA COLONIES With the exception of one small colony in the Los Coronados Islands of Mexico, estimated to contain about six birds (Jehl pers. comm.), the entire known world's population of Ashy Storm- Petrels inests on islands off the CaUfomia coast. More than 75 percent (4,000 birds) of the recorded population nests on the Farallon Islands (429 012). The remainder of the population, except for a small colony at Bird Rock (404 010), nests in the Channel Islands. Nine colony sites have been found in the Channel Islands. Major colonies are located on Prince Island (501 004) with 600 birds. Castle Rock (501 005) with 200 birds, and Santa Barbara Island (524 009) with 250 birds. Addi- tional smaU colonies are located on San Miguel Island (501 006), and small islets offshore of Santa Barbara and Santa Cruz Islands. Although additional small colonies of Ashy Storm-Petrels may exist in the Channel Islands and elsewhere along the Cahfomia coast, the largest colonies have probably been identified. All identified colonies together contain approximately 5,200 birds. It seems unlikely that the population exceeds 10,000 birds, allowing for possible under- estimation of known colonies and the existence 24 California Colonies Catalog Total 5,187 birds • = colony sites 77% Percent of California Breeding Population. Breeding Chronology Norttwm Caljfofnia Clutch- 1 Incubation Period - 42 d«y« Nestling Period ■ 76 dey> (1) Not Breeding Haabers In parentheses correspond to the references from which we obtained the data . Farellon Itlandi n = p~» Channel lilarxlt ^ eggleying lAi U) ^^ egg laying ' 7 ' hetching (2a,29> 7 ? 7 fledging 7 7 7 adults preMnt Jan. I Feb. | Mar. | Apr. | May | June | July | Aug. | Sep. | Oct. I Nov. | Dec. of non-breeding birds and some small undiscovered colonies. Preserve. The remainder of the Channel Islands have recently been designated a National Park. HISTORICAL STATUS AND VULNERABILITY Populations of Ashy Storm-Petrels along the California coast have probably changed Uttle in size over the years, although httle information on their historical status exists. Ainley and Lewis (1974) discuss the history of Ashy Storm-Petrels on the Farallon Islands where observations of storm-petrels were made as early as 1 862. Relevant historical material for the Channel Islands is summarized by Hunt et al. (1979). Ashy Storm-Petrel colonies can be affected by disturbance by humans and terrestrial pred- ators. Adults are vulnerable to surface oil slicks, but fortunately they disperse widely along the coast, a habit which reduces the chances that a large percentage of the population will contact a particular pollutant. However, during the fall large numbers of Ashy Storm-Petrels are known to concentrate in Monterey Bay (Ainley 1976). The small world population of Ashy Storm- Petrels has restricted breeding and wintering ranges. Each known area of concentration, both during breeding and non-breeding seasons, is valuable to the species. Fortunately, the most important nesting sites in CaUfomia are protected, the Farallon Islands as a National Wildlife Refuge and Santa Cruz Island as a Nature Conservancy 25 Black Storm-Petrel (Oceanodroma melania) World Breeding Range The Black Storm-Petrel merits the distinction of being the rarest breeding seabird on the CaUfomia coast. They are known to nest in California only at two sites in the Channel Islands which together contain approximately 150 birds (Hunt et al. 1979). Although Black Storm-Petrels were not discovered nesting in CaUfomia until 1976 (Pitman and Speich 1976), they have been known to breed in the nearby Los Coronados Islands since 1898 (Anthony 1898). Fall dispersal from the breeding colonies is generally southward Jout wintering birds have been observed in offshore waters from San Francisco south to Ecuador. They seem to prefer relatively warm ocean waters. Black Storm-Petrels feed primarily on small fish and invertebrates taken near tne ocean surface and on garbage discarded by passing ships (Anthony 1898, Willet 1933, Murphy 1936). CALIFORNIA COLONIES Black Storm-Petrels nest in California only on Santa Barbara Island (524 008) and nearby Sutil Island (524 009) in the Channel Islands (Hunt et al. 1979). The population estimate of 150 breeding birds was deduced primarily by mist net banding and recapture during several nights in 1977 (Hunt et al. 1979). Since Black Storm-Petrels nest in low densities in scattered natural crevices and burrows of other species, censusing is extremely difficult (Bent 1922, Palmer 1962) and little is known of this bird's breeding biology. Additional nesting locations may exist in southern CaUfomia. Breeding Black Storm-Petrels are present 8 kilometers south of the U.S. -Mexico border in Los Coronados Islands. This population is estimated at approximately 200 birds and appears "stable (Jehl pers. comm.). HISTORICAL STATUS AND VULNERABILITY The size of historical breeding populations of Black Storm-Petrels in California is unknown, but it seems unUkely that this species has ever been common. SmaU numbers of breeding petrels nesting on Santa Barbara Island could easily have been overlooked by previous investigators (Hunt et.al. 1979). Small peripheral breeding populations such as the Channel Island colonies are extremely vulnerable to extirpation (MacArthur and Wilson 1967). The Santa Barbara and Sutil Island colonies could be destroyed by disturbance either of the breeding grounds or of offshore wintering areas, and care should be taken to protect these sites. Population declines at the more populous colonies in Mexico may have a negative effect on the CaUfomia colonies by reducing potential breeding recruitment. Fortu- nately Santa Barbara and Sutil Islands and the nearest Mexican breeding Islands are protected as sanctuaries by their respective govemments. 26 California Colonies Catalog Total 150 birds • = colony sites Percent of California Breeding Population. Breeding Chronology Northern California Incubation Psriod - 42dav«7 7 Nestling Partod - 70 • 7S dayi 7 ? Not Braading Numbers in parentheses correspond to the references from which we obtained the data. Central California Channel Islands —I hatching A/o data available for Channal ft/andt populationt. Chronology constructad from datet of aggs collactad in Los Coronados Islartdt of Mexico. ^fib (31) ftodging ! adulti prmiit Jan. I Feb. I M»f. j Ape. I May I Jiin« | July | Au«. I S«p. I Oct. I No». | D«c Black Storm-Petrels are considerably larger than Ashy Storm-Petrels. Photo by Robert L. Pitman 27 Brown Pelican (Pelecanus occidentalis) World Breeding Range The Brown Pelican is one of the most conspicuous and easily {identifled members of the marine avifauna of California. It is included on the endangered species list of the U.S. Fish and WildUfe Service. In CaUfomia, Brown PeUcans are slowly increasing in number, but their continued recovery is uncertain. The large number of Brown Pelicans in California during summer, fall, and early winter belies the actually small breeding population. Many birds migrate northward from Mexico after breeding in spring. These birds feed and molt in California and southern Oregon before returning to Mexico in early winter. Brown Pelicans in California and Baja California, Mexico, build large stick nests on the ground (Gress 1970). The lusterless, white eggs are incubated by adult pelicans using their webbed feet; a habit characteristic of many birds in the order Pelecaniformes (pelicans, boobies, cormo- rants, frigatebirds, and tropicbirds). Brown Pelicans feed by making spectacular plunges into the water. Throughout their range, fish are the chief food!(Palmer 1962). The Northern Anchovy (Anderson et al. 1975, 1980) makes up nearly the entire diet of breeding birds in California. Reproductive success of Brown Pelicans can vary markedly from year to year. Changes in oceanographic conditions and in the distribution and abundance of forage fish are two interrelated factors that may account for this fluctuation. CALIFORNIA COLONIES Brown Pelicans breed regularly in California only on West Anacapa Island (502 007). In recent years they have also nested intermittently on Santa Barbara Island (524 008) and Scorpion Rock (502 010). HISTORICAL STATUS AND VULNERABILITY The California breeding range of the Brown Pelican formerly extended as far north as Bird Island (454 009) near Monterey. Pelicans have bred only sporadically on this island since the colony was discovered in 1927, and the last successful nesting attempt was in 1959 (Williams 1927, Baldridge 1973). Historically, West Anacapa Island has been the island most consistently used for nesting by Brown Pelicans in California. Before 1929, birds nested primarily on East Anacapa Island but establishment of a lighthouse there likely caused the breeding population to shift to West Anacapa Island. Population estimates for Brown Pelicans on Anacapa Island have fluctuated considerably over the years and are summarized by Anderson and Anderson (1976) and Hunt et al. (1979). Historical records also exist of Brown Pelicans nesting on Prince Island (501 004), Santa Cruz Island, and Santa Barbara Island (524 008). Brown Pelicans were last recorded nesting on Prince Island in 1939 (Sumner 1939). The only record of pelicans nesting on Santa Cruz Island was made by Wright in 1909 (Willett 1912), although up to 1 60 birds have nested on nearby Scorpion Rock (502 010) in 1972, 1974, and 1975 (Anderson and Anderson 1976). Brovvm Pelicans were first observed breeding on Santa Barbara Island in 1911 (Willett 1912) and have nested intermittently there until 1980 (Gress 28 California Colonies Catalog Total 2, 690 birds • = colony sites = former sites Percent of California Breeding Population. Breeding Chronology Northern C«lilQmi« (20,21,29) Clutch - 2-3 Incubation Period - 30 day* Nestling Period - 13 weeks Not Breeding lumbers in parentheses correspond co the references from which ve obtained the data. Bird Island «S4 009) i 1 egg laying 7 hatching No nming tnempn i/nc« I96S. Branding chronology from cambintd yaart 1933 to 1959. SM text. J : ? ?: fledging (7) idutts pTMcnt Channel Islands egg laying hatching 17.20) fledging adults present Jan. I Feb. | Mar. | Apr. | May | June | July | Aug. | Sep. I Oct. I Nov. | I pers. comm.). In the late 1960's and early 1970's, the reproductive success of Brown Pelicans declined considerably in CaUfomia and northern Mexico. From 1969 to 1971 only 12 chicks fledged out of 2,368 nesting attempts (Gress et al. 1973, Anderson and Anderson 1976). The breeding failures of Brown Pelicans during this period were related to the high levels of DDE, the principal metabolite of DDT, in the marine environment (Schreiber and Delong 1969, Schreiber and Riseborough 1972, Riseborough et al. 1971, Jehl 1973, Anderson and Anderson 1976). Brown Pelicans in CaUfomia feed at the top of a food chain that also includes plankton and anchovies. At each higher level of this food chain, concentrations of pesticides were magnified until^- in Brown PeUcans, metabolism and depo- sition of calcium in eggs were impaired and egg shell thicknesses were reduced as much as 50 percent from normal (Anderson et al. 1975). Breaking of thin-shelled eggs under the weight of incubating adults reduced hatching success to almost zero (Gress et al. 1973). Dumping of DDT into the sewage system of the Los Angeles area ceased in 1970 and since 1972 the reproductive success of the Brown Pelican in southern California and northern Mexico has improved. Ten years after the DDT dumping ban, DDE levels have stabilized at lower levels than in the past, but the effects of this chemical on the Brown Pelican continue. Brown Pelicans reach the northern limit of their breeding range in southern California. Historically, breeding populations of Brown PeUcans in southern California have fluctuated in response to environmental conditions. Current thought suggests that these populations increase during periods of ocean warming (Baldridge 1973, Anderson and Anderson 1976). The recent history of this natural population flux has been complicated since the 1950's by a consistent decline in the numbers of Brown PeUcans because of environmental contamination by chlorinated hydrocarbons (Anderson and Anderson 1976). Although the threat of environmental contamination by pesticides has diminished, the future of the Brown PeUcan in California is not necessarily secure. Brown PeUcans can be seriously affected by oil spUls since they plunge dive to feed and often sit on the water. They are limited to nearshore areas where oil spills are likely to be most common and severe. Brown PeUcans in southern California feed almost exclusively on Northern Anchovies, a fish also in great demand by man. A sustained high commercial catch could deplete the fish stocks necessary for success- ful peUcan nesting. Any changes in anchovy management must take into account the require- ments of a potentiaUy expanding population of Brown Pelicans. Breeding Brown PeUcans are highly suscep- tible to disturbance. Reproductive success is lower in colonies that have been disturbed by man than in those imdisturbed (Anderson and Keith 1 980). Increases in the number of tourists at several colonies in Mexico could cause a serious decrease in the reproductive success of this species .md might have important effects on southern California populations. 29 Double-crested Cormorant (Phalacrocorax auritus) Double-crested Cormorants are the most widespread of all cormorants in North America. They are also the only cormorant in the United States and Canada regularly found in freshwater habitats. In CaUfomia, Double-crested Cormo- rants are found breeding along the coast and inland near large rivers and lakes. Despite their widespread breeding distribution, they are probably the least abundant of the cormorants in California. Double-crested Cormorants nest in a variety of habitats. Along the coast they nest on offshore rocks and islands, on abandoned wharf timbers, and on power poles in coastal bays. Cormorants living inland nest in trees or snags, around lakes, or on islands within the lakes. They construct nests of sticks or matted vegetation gathered near the colony. Double-crested Cormorants are sleek and strong swimmers that prey on shallow-water fish (Robertson 1974). After their fishing sessions, they are frequently seen extending their wings to dry. Cormorant feathers become completely saturated during underwater swimming and require periodic drying (Rijke 1968). Many Double-crested Cormorants which nest on coastal rocks and islands feed in nearby bays and rivers of the mainland. Even birds nesting as far offshore as the Farallon Islands (429 012) may come to the coast to feed if local food supplies are poor (Ainley pers. comm.). CALIFORNIA COLONIES Double-crested Cormorant colonies are located in the Channel Islands and Farallon Islands and on nearshore rocks and islands north of San Francisco. There are 17 coastal sites listed in this catalog. The largest of these sites is Prince Island (325 003) with 450 birds. Other large colonies are Old Areata Wharf (325 038) with 340 birds and the Farallon Islands (429 012) with 180 birds. The remaining 14 coastal sites have 150 or fewer birds. The total breeding population on the coast of CaUfomia now contains about 1,900 birds. The largest inland population in CaUfomia breeds near Tule Lake, Siskiyou County (Kelly pers. comm.). HISTORICAL STATUS AND VULNERABILITY Populations of Double-crested Cormorants on the Channel Islands may have declined in size significantly since the tum of the century, but numbers may now be increasing (Hunt et al. 1979). The reasons for the prolonged decline are unknown. However, in the late 1960's and early 1970's pesticide contamination caused thinning of eggsheUs of Double-crested Cormorants and Brown Pelicans in the Channel Islands, considerably lowering the reproductive success of these two species (Gress et al. 1973). EggsheU thinning in Double-crested Cormorants has also 30 10% Calitornia Colonies Catalog Total 1,884 birds* • = colony sites Percent of California Breeding Population. coastal population only Breeding Chronology Northern California CMC..2.7 '5,i,J7, Incubation Period - 26 - 27 dayi Nestling Period -36-42 days hatchinfl fledging Faralton Islarkdt hatching ■ ?7 fledging 177 aduftt preaent Channel Islands ^^ ^^ hatching «ii fledging 0) adults pmant (1) (29) ^ adults prssant Jan. I Feb. \ Mar. [ Apr. [ May | June | July | Aug. | Sep. | Oct. | Nov. | Pec. been documented at the Old Areata Wharf (325 038) colony in northern CaUfomia (Ayers 1975). On the Farallon Islands, Double-crested Cormorants were once the second most abundant species of cormorant, numbering in the low thousands (Ainley and Lewis, 1974). This population of cormorants declined in size between the 1800's and the early 1900's as a result of disturbance by commercial egg collectors. The population has not yet recovered, although egg collecting stopped long ago. Its failure to do so may be related to the disappearance of the Pacific Sardine (Sardinops caerulea) from central and northern CaUfomia (Ainley and Lewjs 1974). We compared the number of Double-crested Cormorants observed in the region north of Cape Mendocino during our study with Osborne's (1972) results and found that numbers had increased at three sites. Nests were absent from two other sites, but we found six additional colonies unreported by Osborne. The total number of Double-crested Cormorants in this region has apparently increased from 530 in 1970 to 1,200 in 1980. These few data suggest that Double-crested Cormorants may be increasing in number on the north coast of California, but since yearly variations in nesting effort occur and cormorants have shown a tendency to switch nesting islands often, caution in such speculation is recommended. Human disturbance of Double-crested Cormorant colonies can be very destructive (Ayers 1975). Comiorant eggs and chicks are vulnerable to gull predation when adults are frightened off their nests by human intrusion (Kury and Gochfeld 1975). Inland colonies have probably been disrupted to a greater extent than any other Double-crested Cormorant colonies in the state because of lake development and recrea- tion (Kelly pers. comm.). Little is known of the vulnerabiUty of cormorants to oil, but few oUed birds have been found after California oil spills (Small et al. 1972, Berkner pers. comm.). Cormorants are mobile and it is likely they can avoid oil spills to some degree. Unlike other seabirds, cormorants spend large amounts of time out of the water. The greatest numbers of Double-crested Cormorants are found along the coast in winter, since many inland breeding birds move to the coast at this time of year. 31 Brandt's Connorant (Phalacrocorax penicillatus) #» «»^^> World Breeding Range Brandt's Connorants are the most abundant and conspicuous of the cormorants nesting on the California coast. Present the length of the California coast in summer, they leave areas of breeding concentration on the north coast and the Farallon Islands in early winter and disperse along the central and southern coast (Osborne 1972, DeSante and Ainley 1980). Brandt's Cormorants usually nest on the flat tops of offshore islands or, less frequently, on inaccessible mainland bluffs and cUff ledges. During the breeding season, these cormorants present a striking appearance with their bright blue throat pouches and white feather plumes on the sides of their heads. At colonies, Brandt's Connorants are opportimistic gatherers of nesting material (Hunt et al. 1979). They collect nearby grasses and herbaceous plants and pluck seaweeds from close tidal rocks. Once nests are constructed, continual additions are made, often with material stolen from neighboring nests (Palmer 1962). Nesting adults stand on their clutches of chalky blue eggs, incubating with their webbed feet. The young are bom without feathers, but soon are covered with coal black down. Nestlings feed by inserting their heads down the throats of their parents and removing partly digested fish remains. Strong swimmers and divers, Brandt's Cormorants prey on various species of fish (Hubbs et al, 1970, Scott 1973, Baltz and Morejohn 1977). Clay (1911) has reported Brandt's Cormorants caught in fishing nets at depths as great as 70 meters. These cormorants frequently feed in large flocks, often in company with other seabirds (Bent 1922). CALIFORNIA COLONIES Brandt's Cormorants usually form large colonies compared to most other California nesting seabirds. The largest aggregation of Brandt's Cormorants is on the Farallon Islands (429 012), where 28,000 birds nested in 1979 (Ainley pers. comm.). At least 13 colonies contain more than 1,000 birds. Over the years, Brandt's Cormorant colonies shift from one location to another (Hunt et al. 1979, this study). Two hundred birds were recorded nesting on Casket Rock (379 009) in 1969; no nests were observed in 1979, but 330 birds nested there in 1980. Similar fluctuations occurred at White Rock (379 010), "333 Point" (379 032), and Arched Rock (404 006). Reasons for these movements are not well understood, but cormorants may have abandoned Prince Island (501 004) in 1977 because of a heavy flea infestation (Hunt et. al. 1979). HISTORICAL STATUS AND VULNERABILITY Brandt's Connorant populations in the Channel Islands have declined in size since they were first recorded there in the late 1800's (Hunt 32 44% California Colonies Catalog Total 64,210 birds • = colony sites Percent of California Breeding Population. Breeding Chronology Nofthfn C*tifotni» TTT^ Cluto.- 26 I (-1,25,29; Incubation Period - 28 - 32 day* N««tlinfl Pf iod ■ 40-42 days Farailon Islands r~l = pa* laving (14,35,42) «dutt» piwit cduHs prwMit ChwHWl lilands ^^ anlayina (1) (28,29) ■dultl pfMMIt ■fan. 1 F«b. I Mar. | Apr. | May | Jun« | July | Aug. | S«p. | Oct. | Nov. | C»c et al. 1979). Hunt et al. (1979) speculate that they were affected first by human disturbance and later by the accumulation of pesticide residues. Thin eggshells, similar to those caused by DDE concentrations in Brown PeUcans and Double- crested Cormorants on the Channel Islands, were seen in Brandt's Cormorant eggs on San Nicolas Island (524 01 1) and Lion Rock (477 Oil) (Hunt etal. 1979, Frame 1972). Brandt's Cormorants on the Farailon Islands declined in number during a period of high human disturbance in the mid-1 800's. Populations began to increase in size after this period of exploitation, and by 1972 there were 22,000 Brandt's Cormorants breeding on the islands (Ainley and Lewis 1974). About 28,000 Brandt's Cormorants now occupy the Farailon Islands (Ainley pers. comm.). Our population estimates for colonies along the remainder of the California coast are nearly double population figures from 1969 and 1970 (Osborne and Reynolds 1971). The difference may be due, at least in part, to more accurate censusing rather than to real population changes. It may also reflect an unusually high nesting effort in 1979. Changes in ocean conditions from year to year apparently influence breeding populations of Brandt's Cormorants. Periods' of upwelling, which bring cold, rich waters to the surface and trigger plankton blooms, are of great importance to seabirds. When warmer ocean waters prevail. the quantity of food drops. Breeding populations of seabirds become smaller and reproductive success declines. Favorable ocean conditions in 1979 caused a boom year for Brandt's Cormorants on the Farailon Islands, where up to 28,000 birds nested. Conditions in 1980 were less favorable, and only about 16,000 birds nested there (Ainley pers. comm,). Brandt's Cormorants are vulnerable to disturbance during the breeding season. Adults flush from their nests readily when approached by boats, low flying aircraft, or humans on foot. Once parents are away from the nests. Western Gulls are able to prey upon eggs and chicks. Repeated disturbance can cause permanent colony desertion. Reported cormorant deaths from oil spills are not frequent (Berkner pers. comm.), and Brandt's Cormorants made up only one percent of the recovered birds in the 1971 San Francisco oil spill (Small et al. 1972). The relative low number of oiled cormorants found on beaches may reflect a greater tendency to sink than in other seabird species (Harris per. comm.). Brandt's Cormorants are likely the most vulnerable of all cormorants to localized oil spills because of their large breeding concentrations. . 33 Pelagic Cormorant (Phalacrocorax pelagicus) The Pelagic Cormorant is the most ubiquitous cormorant in California. These smallest of the CaUfomia cormorants can be seen during any season in their rocky coastal feeding grounds, where they propel themselves underwater with their strong webbed feet in pursuit of fish and shrimp (Robertson 1974, Hatler et al. 1978). Clay (1911) reported that Pelagic Cormorants are capable of diving to depths of up to 140 meters. Pelagic Cormorants nest in scattered groups whose locations sometimes shift from one year to the next (Benz and Garrett 1978, Nysewander and Barbour 1979). Situated anywhere from hundreds of feet above the ocean to just within the spray zone, they raise their young in platform nests of seaweed built on small outcrops and ledges. These cliffside colonies stand out because of the summer whitewash they receive and can be seen for great distances. Although Pelagic Cormorants are shy birds, their nesting activities may be observed at a judicious distance. One of the best locations in the state for observing their breeding behavior is Salt Point State Park (see Appendix B). Pelagic Cormorants are often found nesting close to other cormorants. In these locations, direct competition is apparently reduced by staggered nesting chronologies and by differences in nest site selection, behavior, and in selection of food types, food sizes, and feeding locations (Benz and Garrett 1978, Robertson 1974). CALIFORNIA COLONIES Pelagic Cormorants nest in suitable habitat along the entire coast of California. Forty-four percent of the California population nest on offshore islands, while 56 percent nest on precip- itous cliffs of the mainland. In some regions, small groups of nesting Pelagic Cormorants are scattered in a continuous band along the coast. In these areas our designation of colonies has some- times been arbitrary. That is, the hmits of colonies are often assumed for convenience to be geographical landmarks such as coves or points of land, and frequently long stretches of coastline are included under a single colony number. For example, the Triplett Gulch colony (404 021), one of the largest listed in the catalog, encompasses approximately two kilometers of coastline and numerous offshore rocks. Fish Rocks colony (404 003) on the other hand, although of similar magnitude, consists of two discreet islands in this same vicinity. Although Pelagic Cormorants occur through- out the coastal region, certain areas of con- centration stand out. Areas immediately north of San Francisco have a disproportionately large percentage of nesting birds, as do theFarallon Islands (429 012). Pelagic Cormorants occur in decreasing numbers farther and farther south of San Francisco to the southern terminus of their nesting range. This California distribution may reflect available nesting habitat or perhaps more subtle oceanographic or biological factors. 34 12% 5%/ 24% 1 23%\ 12% — sj? 12% > 5% California Colonies Catalog Total 15,870 birds • = colony sites Percent of California Breeding Population. 4%\ 3% ^ pi-> X Breeding Chronology Nofthem Calilomii •gg laying C,u.c..3.7 f^S'^^'W Incubation Pwiod * 33 days Nestling Period ■40-50 days Farallon Islands (35) adults prtMnt Channat Islands 7 hatdiing fledging a) (29) Jw. I Feb. I Mm. | Apt. | Miy | Junt | July | Aug. | S«p. j Oct. | No». | I HISTORICAL STATUS AND VULNERABILITY Detailed information on the historical status of Pelagic Cormorants exists for only limited portions of the California coast. In the Channel Islands there has been httle change in either total number or distribution during the last century (Hunt et al. 1979). In contrast, Pelagic Cormorant populations on the Farallon Islands (429 012) -dechned greatly in size during the 1850 to 1900 period of egg collecting (Ainley and Lewis 1974). The population has been recovering throughout this century and is still increasing in 1 980 (Ainley pers. comm.). Historical population estimates for northwest California are available from Osborne and Reynolds (1971), although differences in time of survey and survey technique limit comparisons with our 1979-80 data. The tendency of Pelagic Cormorants to move nest sites in succeeding years (Benz and Garrett 1978, Nysewander and Barbour 1979), makes surveys of large areas desirable for this species. Shoreline use and development pose a great threat to Pelagic Cormorants in California. Cormorants can be disturbed by any human activity near colonies. Approach to nesting birds by boats, planes, and humans on foot may force adults off their nests, leaving eggs and yoimg chicks unprotected. Chicks and eggs may be knocked from nests and predation by Western GuUs and Common Raven may increase following the adults' panicked retreat. Pelagic Cormorants, like other members of the order Pelecaniformes, may be vulnerable to pesticide pollution. The egg shell thinning, egg breakage, and subsequent population declines experienced by both Brown Pelicans and Double- crested Cormorants in | southern Cahfomia (Cress et al. 1973) are yet undocumented for Pelagic Cormorants (Hunt et al. 1979). Oil spills in California have resulted in few known cormorant deaths to date (Aldrich 1938, Moffitt and Orr 1938, Small et al. 1972, and Berkner pers. comm.). Because of their widespread distribution and ability to shift colony sites. Pelagic Cormorant populations are relatively resistant to localized oil slicks. Individual cormorants may avoid surface oil (Berkner pers. comm.), and their habit of spending nights and much of the day roosting on rocks further reduces vulnerability to oil pollution (Small et al. 1972). 35 Black Oystercatcher (Haematopus bachmani) Blade Oystercatchers are shorebirds of the outer coast of the northwest Pacific. Adults estabUsh breeding territories on mainland rocky beaches and offshore rocks and islands. An oystercatcher nest, composed of a scrape lined with pebbles and shell fragments, is surprisingly difficult to find. One to three cryptically colored eggs are placed directly on the pebbles. Black Oystercatcher young are precocial and may leave the nest within hours of hatching. Although they remain near the nest at first, within a few days chicks follow adults to intertidal foraging areas. The California mussel (Mytilus califomianus) is the chief food of oystercatchers in the Channel Islands (Hunt et al. 1979) as well as in northern Cahfomia (Helbing 1977), and limpets and chitons make up most of the remainder of the diet. Chicks at the nest are frequently fed crabs (Hartwick 1976, Helbing 1977). Mortality among eggs and chicks is apparently high. Hartwick (1974) lists gull predation as an important cause of mortality. In addition, chicks and eggs are frequently washed "overboard" from nests by storm waves. During the winter, oystercatchers are gregarious (Webster 1 94 1) and can be observed feeding along rocky portions of the California coast. With their bright orange bills, pink feet, and loud distinctive call, these birds are con- spicuous. CALIFORNIA POPULATION Black Oystercatchers are a non-colonial nesting species, although they are usually found on the same offshore islands and rocks as colonial nesting seabirds. They establish large nesting and feeding territories and thus distribute themselves along the available coastal habitat. Actual nests were pinpointed only for a small percentage of the sites listed in this catalog. Nesting was indicated more often from the territorial defense behavior of adults. This method obviously has limitations since approach to a nest must be close enough to initiate a reaction from the adults. For this reason the catalog total for this species is almost certainly low. The actual breeding popu- lation size is probably about 1 ,000 birds. Information presented in this catalog gives a good representation of the overall breeding pattern of this species, a population of single nesting pairs widely dispersed along the entire California coastline. Concentrations of 242 Black Oystercatchers in the Channel Islands and 40 breeding birds in the Farallon Islands (429 012) represent nearly half of the catalog breeding total. HISTORICAL STATUS & VULNERABILITY Black Oystercatchers disappeared from the 36 CalHornia Population Catalog Total 704 birds • = nest sites Percent of California Breeding Population. Breeding Chronology Northern California ■3 ] f'?' Clutth- 2-3 1 '*• ' ' IncutMtion Partod - 2S • 30 d«yt Nestling Period - 36 * 40 day* eggleying hatdiinf 7 ^ ? ^4 4^14,27,35) ■duto pfnt Farailon Islands Channel Itlandi (291 n. I Feb. | Mar. | Api. | May | June | July | Aua- | Sep. | Oa. I Nov. | 0«c Farailon Islands in the 1860's, possibly as a result of too much human disturbance. A few birds were seen in 1903, but oystercatchers were not observed there on a regular basis until 1956. The breeding population of Black Oystercatchers on the Farailon Islands increased to 16 by 1959 and to 40 in 1972 (Ainley and Lewis 1974). Since that time the population has stabilized and may be at its maximum (Ainley pers. comm.). Historical population information for areas other than the Farailon Islands is almost nonexistent. Black Oystercatchers require clean and undisturbed rocky coastlines for nesting and feeding. To the extent that these areas are disturbed by humans, reproductive success will be reduced. OH spills, which foul rocky coastlines where oystercatchers feed, could seriously affect the food supplies of this species, but losses of birds from direct oiling would probably be low. Long-term degradation of intertidal habitat would almost certainly cause population declines. \Black Oystercatchers Photo by Ian C. Tait 37 Western Gull (Laws occidentalis) World Breeding Range Western Gulls are the breeding gull of the California coast. They breed as far south as Baja California, Mexico, and as far north as Washington and southern British Columbia. Western Gulls in Washington and British Columbia are sym- patric with Glaucous-winged Gulls (Lams glau- cescens) with which they hybridize extensively (Hoffman et al. 1978). Western Gulls nest in a wide variety of habitats, but usually are found in the greatest densities on the flatter portions of islands and offshore rocks. Some nest on the mainland and these nests are always confined to areas inaccessible to mammahan predators such as steep slopes and cliff faces. Western Gulls will even nest on man-made structures. Their nests are substantial and are usually constructed of vegetation gathered near the colonies. Western Gulls usually lay clutches of from one to three eggs, although in the Channel Islands clutches of from four to six eggs result from female-female pairing. The eggs in these supernormal clutches are usually infertile and do not hatch (Hunt and Hunt 1977). Western Gulls feed on a variety of prey. Important food items from around the Farallon and Channel Islands include anchovies, rockfish (Sebastes), Pacific Sauries (Cololabis saira), midshipmen (Porichthys), cephalopods, euphausi- ids, barnacles, and offal (Ainley and Sanger 1979, Hunt et al. 1979). Like large gulls elsewhere in the world. Western Gulls often feed on human refuse at dumps scattered along the coast. CALIFORNIA COLONIES Although Western Gulls breed widely along the California coast, most of the breeding popu- lation is concentrated at a few sites. The 32,000 gulls of the Farallon Islands (429 012) make up more than 60 percent of the entire breeding population in California. Other large colonies in California are at Middle Anacapa Island (502 008) with 5,000 Western Gulls, Santa Barbara Island (524 008) with 2,300 gulls, San Nicolas Island (524 Oil) with 1,800 guUs, Castle Rock (325 006) with 1,350 gulls, and Prince Island (501 004) with 960 gulls. Most of the Western GuU colonies in California, however, are much smaller. Sixteen of the remaining sites have between 100 and 500 birds, 22 sites have between 50 and 100 birds, and 115 sites have fewer than 50 birds. HISTORICAL STATUS AND VULNERABILITY Western Gulls are probably the least likely of California seabirds to suffer population declines as a result of mail's activities. The population may in fact be growing as the result of an abundant food supply at garbage dumps. Increases in numbers of large gulls may not be desirable since these birds can harm other seabirds and interfere with aircraft at airports. Increases in the size of several populations of large gulls have been attributed to the availability of human food wastes and sewage (Drury 1979, Kadlec and Drury 1968, Vermeer 1963). Both Herring Gulls (Lams argentatus) and Great Black-backed Gulls (Lams marinus) in eastern North America have increased in number and caused substantial damage to tern and Atlantic Puffin (Fratercula arctica) colonies by usurping optimal nesting habitat, stealing food (klepto- parasitism), and eating eggs and chicks (Nettleship 1972,Nisbet 1973). 38 CalHornia Colonies Catalog Total 50,930 birds • = colony sites Percent of California Breeding Population. Breeding Chronology NoffHnfW C«lifofni> (2B,29) Clutdi -1-3 Ifwubation Piriod ■ 29 days Nwtllm P«riod ■ 42-4Sd«v» ttadjing Farallon Itlandi (35) adults praaant (1) aduhspcaaawt Channd Islands (28,29) Jan. I Fab. | Mac. | Apr. | May | Juna | July | Aua- | Sap. | Oct. I No». I Oac Populations of Western Gulls in CaUfomia have probably also increased in size during the last two decades, but documentation is difficult to obtain, since historical data for much of the California coast are lacking. Osborne and Reynolds (1971) censused many of the large Western GuU colonies in central and northern CaUfomia, but their data may not be comparable with ours. Certainly differing survey techniques account for some of the differences between the two sets of data. We were able to make a compari- son of Osborne and Reynolds' data and our data for 26 sites and found more Western Gulls at 20 sites in 1979 and 1980 than in 1970, fewer at four sites, and no change at two sites. The apparent net' increase in numbers of breeding Western Gulls at these 26 sites is about 1 ,600 birds. In addition, we found many previously undiscovered sites. This probably reflects in part, our more complete coverage of the coast. These comparisons suggest that the number of Western Gulls in California may have increased during the last decade. Other evidence suggesting that numbers have increased comes from the Farallon Islands and Prince Island (501 004). The number of Western GuUs on the Farallon Islands pliunmeted in the mid-late 1800's primarily because of egg collecting and disturbance from domestic animals (Ainley and Lewis 1974). The population recovered in size to about 23,000 birds in 1959 and remained stable until 1972 (Ainley and Lewis 1974). Since then the population has increased to 32,000 birds and there appears to be a surplus of adult-plumaged birds. On Prince Island, a population of about 500 birds in 1968 (Ruber 1968) increased to about 1,000 birds in 1976 (Hunt et al. 1979). On Santa Barbara Island, however, there has been a marked decline in numbers of Western Gulls since 1972, which appears to be related to the abundance of anchovies (Hunt and Butler 1980). The effects of an increasing population of Western Gulls on other seabirds are difficult to assess. Western Gulls are the most important predators of storm-petrels and Cassin's Auklets on the FaraUon Islands (Manuwal 1974, Ainley et al. 1974), and further increases in Western Gull numbers may increase the rate of predation. Increases in Western Gull numbers elsewhere in CaUfomia could have a similar effect on small alcids and storm-petrels. Western GuUs klepto- parasitize cormorants. Rhinoceros Auklets, and probably Tufted Puffins. The present rate of incidence is unknown but may increase if guU populations continue to expand. This species is probably one of the least vulnerable to oil spills of aU seabird species nesting in CaUfomia, since they are highly mobile and frequently retum to land to rest and roost. Western Gulls, Uke other surface nesting seabirds, are susceptible to disturbances while nesting. Disturbance in a particularly dense colony may result in intraspecific pirating of eggs and canni- baUsm. Chicks frightened from their territories may be kiUed by neighboring gulls or become lost and starve. Nevertheless, the future of the Western Gull in CaUfomia looks secure. With the present pattem of waste disposal in California, Western GuUs wiU probably continue to increase in number. Because of their relatively high reproductive potential, an excess of non-breeding adults, and their abiUty to feed on a wide variety of prey, they would likely make a rapid recovery from any decline. 39 Common Murre (Uria aalge) Common Murres are some of the most highly colonial of all seabirds. Island and mainland colonies are usually densely packed shoulder to shoulder with these noisy, gregarious birds. Common Murres breed in both the North Pacific and North Atlantic Oceans and are some of the most abundant seabirds in the northern hemis- phere. Common Murres prefer to nest on wide, flat cUff ledges and the tops of islands. A large, single egg is laid on bare rock or soil and is narrowly pointed at one end and broad and rounded at the other. Murre eggs vary greatly in color, ranging from white to buff, brown, reddish, blue, or green. They are almost always marked with dark dots, blotches, or intricate scribbling (Harrison 1978). The unique pattern of each egg probably aids individual recognition by adults (Johnson 1941). Murre chicks are fed by both parents and jump from the colonies to the waters below when only partly grown. They are accompanied at sea by only one parent, usually the male (Varoujean pers. comm.). Common Murres are good fliers and are capable of foraging long distances from their colonies. They dive to considerable depths and include flsh, crustaceans, and cephalopods in their diet (Ogi and Tsujita 1973, 1977). Common Murres are often seen in coastal California during the fall and winter months (Ainley 1976) and make frequent landfalls at their colonies during these seasons. CALIFORNU COLONIES In California, Common Murres breed from Castle Rock (325 006) in the northern part of the state south to Hurricane Point Rocks (454 Oil) at the north end of the Big Sur coast. They are known to breed at 19 sites in California and a few non-breeders have been seen on three additional islands. These three islands, Kibesillah Rock (379 004), White Rock (379 010), and Gualala Point Island (404 004), all appear to have suitable nesting habitat and should be watched for future nesting. Colonies of Common Murres, although easy to find, are difficult to census. Variables such as time of year, time of day, and the unknown breeding status of many individuals compUcate an already difficult task (see Materials and Meth- ods). The estimates of murre numbers presented here and in the tables include the number we actually counted or estimated, plus two-thirds of that number to account for members of the breeding pair away from the colony (Ainley 1976). Colonies of Common Murres in CaUfomia vary greatly in size, from as few as 50 birds on Sisters Rocks (325 008) to 126,000 birds on Castle Rock. Other large colonies of murres exist at the Farallon Islands (429 012) with 60,000 birds. Green Rock (325 020) with 55,000 birds, False Klamath Rock (325 010) with 26,500 birds, and Flatiron Rock (325 023) with 24,000 birds. HISTORICAL STATUS AND VULNERABILITY Two lines of evidence suggest that Common Murres are presently increasing in number in CaUfomia. First, in 1979 and 1980 Common Murres were found breeding at four sites where murres were not observed by Osborne and Reynolds (1971), although they censused these 40 17% CalHornia Colonies Catalog Total 363,154 birds • = colony sites o = former sites Percent of California Breeding Population. Breeding Chronology Northern Californil (35) Clul*- I Incubation Period -28-34 deyt Nestling Period - 2o - 28 dayi Ferellon Itlendt : U) Channel Itlandi ■99 laying 7 ^m 7 No coftfirmtd bnrding tinct t912. Grap/i conttnjct*d from lUtnof »ggt colhcfgd in tht Chutntl Itlandt hatching 7 ■■ 7 fledging ^m 7 Jan. I Feb. | Mat. | Ape. | May | June | July | Aug. Sep. [ Oct. I No¥. I Dec same Islands for other species. These islands are: Sisters Rocks, Blank Rock (325 024), Pilot Rock (325 026), and Cape Vizcaino (379 002). Murres may have been present at Cape Vizcaino during the years of Osborne's work but could have left the colony prior to his survey in August. Second, there are 14 breeding colonies of Common Murres for which both Osborne and Reynolds (1971) and we have estimates. Our estimates greatly exceed theirs in all cases, usually by a factor of two, three, four, or more. Even if the two-thirds attendance factor is subtracted from our estimates, our totals still exceed Osborne and Reynolds' in all but two cases. In the two instances where ours are lower, Castle Rock and Green Rock, the two estimates are similar. Apparently murre numbers have been increasing throughout much of this century. Osborne (1972) found that the population of Common Murres in the region from Cape Mendocino to the Oregon border has increased from a few thousand birds in the 191 0's to about 143,000 birds in 1970. The history of Common Murre populations at two other sites also suggests that numbers are increasing. Clay (unpubl. field notes) makes no mention of Common Murres at Flatiron Rock between 1910 and 1934, but Osborne estimated that 10,000 birds were present there in 1970. Our estimate for this site in 1979 is 24,000 birds. Clay (unpubl. field notes) estimated 2,000 birds at Green Rock in 1941, compared to Osborne's estimate of 40,000 in 1970 and our estimate of 55,000 in 1980. Common Murres on the Farallon Islands are also increasing in number but in this case the increase follows a documented severe population reduction. Between 1854 and 1959 the population dropped from 400,000 birds to between 6,000 and 7,000 birds. A commercial egg harvest and oil pollution were the primary causes of this reduction (Ainley and Lewis 1974). With strict protection, the population increased to 20,500 birds in 1972 and to 60,000 birds or more at the present time. Common Murres formerly bred on Prince Island (501 004) in the Channel Islands but no longer do so. Hunt et al. (1979) states, "Since the tiny colony at Prince Island was so far south of the nearest murre colony, it seems likely that repeated visits by early egg collectors, coupled with the slim possibility of recruitment from other colonies, could have eliminated murres as a breeding species. . . ." Nesting Common Murres are very sensitive to disturbance by boats, low-flying aircraft, and humans on foot. When disturbed, adults flush from the colonies and may knock eggs and chicks from nest sites. The remaining chicks and eggs are subject to increased predation from gulls and ravens. Common Murres are highly vulnerable to oil contamination and were some of the most frequently oiled birds in the 1971 San Francisco oil spill (Small et al. 1972). They are common in the coastal zone of California throughout the year and spend large amounts of time on the water. They appear to be highly social during both the breeding and non-breeding seasons and frequently congregate on waters adjacent to their colonies. Future oil spills along the CaUfomia coast could kill large numbers of this species. 41 Pigeon Guillemot (Cepphus columba) Pigeon Guillemots inhabit the nearshore zone and are usually found along stretches of rock coastline. They are most easily observed in the early morning, before the egg laying season, when both members of each pair frequent waters adjacent to their colonies. Pigeon Guillemots usually nest in natural rock crevices, talus, and boulder beaches (Thoresen and Booth 1958, Drent 1965). They also use burrows dug into loose conglomerate bluffs and man-made structures, such as wharf timbers, drain pipes, and within truck tires slipped on wharf pilings (Campbell 1977, this study). In some regions of California, Pigeon Guillemots and introduced Rock Doves (Columba livia) may be competing for nesting space. Pigeon Guillemots are some of the few alcids to regularly lay two eggs (Bent 1946, Thoresen and Booth 1958, Drent 1965). Eggs are laid on bare rock, soil, or sometimes on a bed of pebbles and shell fragments. Guillemots usually feed close to shore and the proximity of the feeding grounds to the colonies may help explain their abiUty to sometimes raise two chicks. Pigeon Guillemots, like all members of the family Alcidae, dive for food using their wings for propulsion. In California, fish are the principal food of guillemots during the breeding season (Follett and Ainley 1976). This appears to be true throughout their breeding range although near Kodiak, Alaska, Pigeon Guillemots are known to eat small crabs and shrimp (Krasnow et al. 1978). Following breeding. Pigeon Guillemots largely disappear from the California coastline and do not reappear until just before the next year's breeding season. Their wintering range is presently unknown but we suspect that a northward move- ment of birds takes place. CALIFORNIA COLONIES In CaUfomia, Pigeon Guillemots breed from the Oregon border south to Santa Barbara Island. They are found breeding in large aggregations of up to 3,000 birds, in smaller groups of only a few birds, or as isolated pairs scattered along the coast in suitable habitat. Delimiting colonies is often difficult, especially in those regions where Pigeon Guillemots are spread along the coast. In many cases, colony boundaries have been based on geographical landmarks and cover large sections of coastline. The catalog total of Pigeon Guillemots in CaUfomia is about 12,000. We feel that this number is conservative, although for any individual nesting site our estimates may be either high or low. Censusing Pigeon Guillemots is at best an inexact science and is compUcated by several factors (see Materials and Methods). Although many Pigeon Guillemot colonies were surveyed in both 1979 and 1980, only the best of the estimates for these two years are included in this catalog. The FaraUon Islands (429 012), with 3,000 birds, have the largest population of Pigeon Guillemots in California. The coastline between Davenport and Point Santa Cruz (454 021) is inhabited by about 1,300 guillemots. Other locations with large numbers are Point Arguello 42 20% California Colonies Catalog Total 14,724 birds = colony sites Percent of California Breeding Population. Breeding Chronology Incubation Period - 30 - 32 dcya Nitling Pwiod ■ 36 - 45 ctoyi Fafalloo lilands Channel lilandt : ggg 'aying hatching HSk adults praaant (i> (29) Jan. I Feb. | Mar. | Apr. | May I Jum | July | An;. | Sep. | Oct. | Nov. | D«c (501 010), Fish Rocks (404 003), Castle Rock (325 006), Sugarloaf Island (325 041), and Prince Island (325 003). Generally, however. Pigeon Guillemot colonies are small. More than half the sites we investigated had fewer than 30 birds. fflSTORICAL STATUS AND VULNERABILITY Few data pertaining to the historical status of Pigeon Guillemots are available. On the Farallon Islands, Pigeon Guillemots escaped early persecution by commercial egg collectors but later fell victims to oil pollution (Ainley and Lewis 1974). The guillemot population of the Farallon Islands reached an all-time low of 200 in 1911. Since then it has recovered steadily, to 1,000 birds in 1959, 2,000 in 1972, and 3,000 at present (Ainley pers. comm.). Elsewhere along the California coast it may appear from the data that Pigeon Guillemot numbers have increased dramatically. However, we do not feel there is sufficient information to make this judgement. Previous investigators largely overlooked Pigeon Guillemots since they often nest in low densities and usually do not form distinct colonies. Censusing Pigeon Guille- mots requires much time and manpower and access to many nesting sites is poor. Time of day and of year can greatly influence survey results and some previous surveys were conducted after Pigeon Guillemots had finished nesting. Compared to other seabirds such as Common Murres and Brandt's Cormorants, Pigeon Guille- mots are not highly prone to disturbance, primarily because of their comparatively low nesting densities and inaccessible nest sites. Pigeon Guillemots will, however, readily desert their nests if disturbed during incubation or brooding. Like murres. Pigeon Guillemots are very vulnerable to oil pollution. Guillemots spend large amounts of time on the water, usually close to land where oil exploration and develop- ment are concentrated. Fortunately, the population of Pigeon Guillemots in California is widely distributed along the coast and any oil spill would most likely affect only local birds. Pigeon Guillemots occasionally nest in man-made structures like this tire on a Crescent City dock. Photo by Anthony R. DeGange 431 Marbled Murrelet (Brachyramphus marmoratm) Dnwing by AlUm Brooks, complimenti of The Munelet, A Jouiml of NoithwMt Onitthototy ind ll«iiiiiii»o«y. The Marbled Murrelet is the only breeding alcid in California that has become adapted to nesting habitats inland from coastal rocks and beaches. The locations of Marbled Murrelet nests are the least known of all the seabirds breeding in Cahfomia. Only four nests have been found throughout the species' entire range; one in Siberia (Kuzyakin 1963), one in California (Binford et al. 1975, Singer and Verardo 1975), and two on East Amatuh Island in the Barren Islands, Alaska (Simon 1980). Kiff (in press) has recently reviewed the known eggs and nests of this species. Of the four nests, both the Siberian and California nests were found in trees, but the Alaskan nests were found on the timdra of a treeless island. The Siberian nest was found in the upper branch of a Larch (Larix dehurica) 6.8 meters above the ground (Kuzyakin 1963). The California nest was found 45 meters above the ground on a moss-covered limb of a Douglas-fir (Pseudotsuga menziesii) in Big Basin Redwoods State Park, Santa Cruz County (Binford et al. 1975). This nest contained a Marbled Murrelet chick sitting in a small depression encircled by" droppings. Binford et al. (1975) theorize that the pale green egg, the cinnamon brown breeding plumage of the adult, and the light brown nestling are cryptic adaptations for nesting in trees. The entire breeding population of Marbled Murrelets in California is suspected to nest in trees. Marbled Murrelets seen at sea during the summer are often in pairs and are usually within 1 to 2 kilometers of the coast. Breeding birds return to their nests in the evening and depart at dawn. We have observed individual birds, pairs, and groups of up to 60 birds in the breeding season flying over the tree tops at the margin of old growth Coast Redwood (Sequoia sempervirens) forests. An amazing display of this behavior can be seen at Prairie Creek Redwoods State Park in Humboldt County (Appendix B). Marbled Murrelets may also use coastal forests in winter as evidenced by calling birds flying over the redwood forests during this season (Strachan pers. comm.). Marbled Murrelets like all other alcids, spend a large percentage of their time on the ocean. They feed on fish and less frequently on crusta- ceans (Sealy 1975b). CALIFORNIA POPULATION We observed Marbled Murrelets during the breeding season on coastal waters from the CaUfomia-Oregon border south to Point Sal, Santa Barbara County. However, two areas of concentration stand out: coastal waters from Eureka to the California-Oregon border and from Santa Cruz to Half Moon Bay. These two regions respectively account for 76 and 14 percent of our 185 Marbled Murrelet sightings made during the 1979 breeding season. During this season our 44 California Population Estimate 2,000 birds Offshore Sighting ■ =high S =low Breeding Chronology Nofthf n 5nd Cfitfll Criifornia Clutdi- 1 (40) Incutxtion Period - 30 days Netiring Period - 23 days (9,40,42) egglayina ? ? hatch tnfl - DiKonrv of chick in nm. S*, rexr Note: CJffomi, chronology i,hl, it mocUtitd fronj indinct widt UurrwtM popolationt. SmSwV. t974;Sm,ly, 197S. . 'danct in Britith Colotnbi, U,rbl,d Southern California Not Braedinti Jan. [ Feb. ) Mar. | Apr. | May | June | July j Aug. | Sep. I Oct. I Nov. I Dec. coverage of the central and northern California coasts was virtually complete. These two regions were again censused in 1980, when we made 390 sightings of Marbled Murrelets, but our coverage of the coastline in that year was less complete. Both regions of high Marbled Murrelet concen- tration are offshore of mature stands of coniferous trees. This suggests that murrelets may require these trees for nesting. After breeding. Marbled Murrelets disperse along the coast of California. They have been recorded as far south as Imperial Beach, San Diego County (McCaskie 1980). It is difficult to estimate the breeding pop- ulation of Marbled Murrelets in California, but we speculate that it is about 2,000 birds. This estimate may be conservative since this small alcid's breeding habits are poorly known. It is difficult to see them at sea in other than perfect conditions, and it is likely that other unobserved murrelets were farther out to sea during our boat surveys. Our observations of Marbled Murrelets were made from a boat incidental to surveys of other nesting seabirds. These surveys were not designed to census Marbled Murrelets in the most accurate fashion but we hope these results shed some Ught on the species* nesting distribution in the state. Further work on Marbled Murrelets is certainly needed and our individual sight records may be of future use to anyone attempting a more complete survey of this species. All records of our observations are included in the Colony Status Records and in our field notes (Appendix A). HISTORICAL STATUS AND VULNERABILITY There is httle information on the historical status of Marbled Murrelets in California. Dis- turbance to nesting Marbled Murrelets probably has been and will Continue to be primarily through the destruction of nesting habitat. Populations of Marbled Murrelets may have been reduced by the destruction of virgin coastal forests, althou^ no data are available. The old growth stands of the coast redwood alone have been reduced in area from an estimated 809,000 hectares (2,000,000 acres) to 93,000 hectares (230,000 acres) (Veirs pers. comm.). We suspect that Marbled Murrelets were formerly more abundant than they are today. Marbled Murrelets are vulnerable to oil contamination since they are often found on waters very close to land. An oil spill along the coastlines of Humboldt - Del Norte Counties or San Mateo - Santa Cruz Counties could endanger a murrelet population that is highly concentrated during the summer months along those two stretches of coastline. 45 Xantus* Murrelet (Endomychura hypoleuca) y^v-^>^ ^\> r ■-^"■^ . Worid Breeding Range The breeding range of the Xantus' Murrelet is restricted to the Channel Islands and the west coast of Baja California, Mexico. This species and the closely related Craveri's Murrelet (Endo- mychura craveri) are thought to be reproductively isolated, even though a small zone of sympatry exists in the San Benitos Islands, Mexico (Jehl and Bond 1975). Before intensive research was begun on Xantus' Murrelets in 1975 by Hunt et al. (1979), little was known about their life history. Most of the information in this account was taken from that study. Xantus' Murrelets nest primarily in rock crevices along or near cliff ledges, but also under bushes, in ground vegetation, in abandoned rabbit burrows, under old pelican nests, and in man-made debris (Hunt et al. 1979). These murrelets, unlike most alcids, usually lay two eggs annually. Eggs are incubated under the wings, next to lateral brood patches on each side of the body. During the breeding season, Xantus' Murrelets spend daylight hours either in the nest or foraging at sea. Other colony activites, such as nest-site selection, incubation shift changes, and fledging, occur at night (Hunt et al. 1979). Xantus' Murrelet chicks are highly precocial and fledge at about two days of age. The small, flightless, downy young leave their nests at night and scurry to the shoreline. Upon reaching the ocean, they plunge in and head far out to sea with their parents. Chicks waylaid during the night or attempting to leave the nests during the day are quickly eaten by Western GuUs. Xantus' Murrelets dive for food and feed extensively on larval fish. Northern Anchovies, Pacific Sauries and rockfish (family Scorpaenidae) are the most important species taken by Xantus' Murrelets in the Channel Islands (Hunt et al. 1979). Of these. Northern Anchovies are the most important and their availability may dramatically influence the breeding success of Xantus' Murrelets (Hunt and Butler 1980). Xantus' Murrelets often forage in the immediate vicinity of their colonies during the breeding season, but disperse widely thereafter. CALIFORNIA COLONIES All California colonies of Xantus' Murrelets are in the Channel Islands. Santa Barbara Island (524 008), where 2,000 to 4,000 birds are esti- mated to breed, is the most important colony for this species in CaUfomia. Hunt et al. (1979) have conducted studies of this species' breeding biology and at-sea distribution at this site. All remaining colonies of Xantus' Murrelets in California are small. Of these. Prince Island (501 004) and Sutil Rock (524 009) are the largest, each with 150 birds, followed by East Anacapa Island (502 009) with fewer than 40 birds. Snag Rock (524 007) with 30 birds, and GuU Rock 46 California Colonies Catalog Total 3,500 birds • = colony sites Percent of California Breeding Population. Breeding Chronology Northern C»ll(orni« Clutdi - 1 ■ 2 Incubation Period ■ 41 rlayi Nastlinfl Period ■ 2 d«vi (28,29) NotBrMdIng Smdbera in parentheses correspond to the references from trhlch we obtained the data. Cmtnl Calilainii Channel Island! Not Breading — 1 egg laying PM* ^^^^ : ■ adults p) (28,29) Jen. I Feb. | Mer. | Apr. | May | June | July | Aug. | Sep. | Oct. | Wo». | Dec (524 001) with two birds. Xantus' Murrelets probably also breed at Scorpion Rock (502 010) and Castle Rock (501 005), and small numbers may occasionally breed at other locations in the Channel Islands (Hunt et al. 1979). HISTORICAL STATUS AND VULNERABILITY The population of Xantus' Murrelets on Santa Barbara Island is apparently recovering from a drastic decUne. Between 1897 and 1908, feral cats (Felis catus) were introduced onto Santa Barbara Island. Few data on the size of the murrelet population prior to the cats' introduction exist, but Sumner (1939) states, "At one time large colonies of auklets and murrelets were present on the island, but none have been recorded in recent years and it is supposed that they have been exterminated by these feral cats". By 1975 the population of cats was reduced to perhaps a single animal and Xantus' Murrelets are now some of the most abundant of breeding seabirds on the island (Hunt et al. 1979). Natural predators of Xantus' Murrelets include the Peregrine Falcon (Falco peregrinus). Deer Mouse (Peromyscus maniculatus), and the Island Fox (Urocyon littoralis). Peregrine Falcons were once common residents of the Chaimel Islands, but now are only present as migrants. Their decreased presence may have contributed to the Xantus' Murrelet recovery on Santa Barbara Island (Hunt et al. 1979). An insular subspecies of Deer Mouse resides on each of the eight large Channel Islands (Nelson and Goldman 1931). They are known to prey on eggs and possibly chicks of the Xantus' Murrelet, but their presence is not a deterrent to successful reproduction (Hunt et al. 1979, Winnet et al. 1979). The Island Fox is present on all large Channel Islands, except Anacapa and Santa Barbara Islands, the only two islands with large seabird colonies. The presence of foxes on the other large islands may account for small populations of seabirds there. Because Xantus' Murrelets, like other alcids, spend a lot of time on the water and dive for food, they are vulnerable to oil spills. Location of spills in the CaUfomia Bight during the breeding season would be the most critical, since adults and recently hatched flightless chicks would be concentrated near their colonies. Xantus' Murrelet Chick 47 Cassin's Auklet (Ptychoramphus aleuticus) ■■.« fRS> The Cassin's Auklet is one of the most widespread members of the family Alcidae in the North Pacific. Cassin's Auklets build their nests in burrows on offshore islands that have a sufficient mantle of soil. These tiny alcids are nocturnal at their breeding colonies and are likely the most pelagic of all the California alcids (Hunt et al. 1979). A population is present on the Farallon Islands (429 0 1 2) all year, but wintering northcoast birds are found between 10 and 50 miles offshore (Manuwal 1974a, Yocom and Harris 1975). Throughout their range Cassin's Auklets usually nest in burrows, but on the Farallon Islands birds also may use rock crevices, debris piles, cracks under buildings, and large caves (Thoresen 1964). Each female lays a single creamy white egg, but may lay a second egg if the first egg is destroyed (Manuwal 1974a). Adult Cassin's Auklets develop two incubation patches on the body, one beneath each wing (Manuwal 1974b). These incubation patches are found only among several species of alcids, including Xantus' Murrelets, Rhinoceros Auklets, and Tufted Puffins. Breeding Cassin's Auklets also develop a gular pouch, used to store food for young that are fed by regurgitation at night (Speich and Manuwal 1974). Small fish and pelagic crustaceans form the mainstay of the diet of Cassin's Auklets (Manuwal 1974a, Hunt et aL 1979). CALIFORNIA COLONIES Cassin's Auklets breed in California from the Channel Islands to Castle Rock (325 006). Of the know colonies in California the Farallon Islands colony is by far the largest, containing 105,000 auklets. Of the 23,000 Cassin's Auklets nesting in the Chaimel Islands, 20,000 are found on Prince Island (501 004). Castle Rock, near the Oregon border, has an estimated population of 3,600 birds. Cassin's Auklets are difficult to census because of their nocturnal Ufestyle, burrow nesting habits, and highly pelagic nature. We found no new colonies during our surveys and have made no new population estimates for this species. HISTORICAL STATUS Surprisingly, Cassin's Auklets were rare on the Farallon Islands in the mid-1 800's. Ainley and Lewis (1974) relate this scarcity to a period of more than two decades when warm, tropical water moved north along the California coast. They hypothesize that populations of Cassin's Auklets increased when cold water returned to the region. Now Cassin's Auklets are the most abundant birds on the Farallon Islands. 48 California Colonies Catalog Total 131,170 birds • = colony sites Breeding Chronology CM*. , " ■^ i Incubation Period - 38dayi r4astling Pariod - 41 . 46 days 3% ] Northern California an laying -4 7 7 7 ; 7: \ ' -"'^"- 7 ^ : : : : n«<«in« jay 7 k "f ■duttipraaai tit 1 J. » \ Fafalkxi Idandi si . (33) 1 • agglayina ladjing 1 ^■v hatching '..'.'. \ •duHipraMM Percent of California Breeding Population. ^ \ ^ ^ ' ' \ \ ' \ 1 Channal lilandt I) 17%*-- 7 aw laying - — *Vj '^X i T ' hatching \ (Mging 7 adutepiaiit / : . : 1 Jan. 1 Fab. | Mar. | Apr. 1 May 1 Juna 1 July 1 Aug. 1 Sap. 1 Oct. 1 Nov. 1 (MG. 1 Osborne (1972) estimated that numbers of Cassin's Auklets on Castle Rock increased from 100 seen in 1959 by Thoresen (1964) to 3,600 in 1970. Cassin's Auklets formerly bred on Flatiron Rock (325 023) as late as 1934 (Clay unpubl. field notes). Osborne (1972) believes that soil erosion was the principal reason for their extir- pation from this island. Western Gulls prey heavily on Cassin's Auklets at Castle Rock and the Farallon Islands (Thoresen 1964). Young are pulled by gulls from shallow burrows and adults are killed at night when they unfortunately land at the feet of roosting gulls (Thoresen 1964). Cassin's Auklets are vulnerable to disturbance from humans and to the depredations of intro- duced predators such as rats. Cassin's Auklets may desert their nests if disturbed during incubation and their burrows can easily be caved in by unwary visitors to their colonies. Fortunately, all colonies of Cassin's Auklets in California except Green Rock (325 020) are protected. Cassin's Auklets feed from the ocean surface in large social flocks where they are highly vulnerable to oil contamination (Hunt et al. 1979). An oil spill near the Farallon Islands, where 80 percent of the state's population breeds, would be particularly damaging to this species. 49 Rhinoceros Auklet (Cerorhinca monocerata) The Rhinoceros Auklet is an uncommon breeding seabird in California. It derives its name from the keratinous "horn" found on its bill during the breeding season. Although this species' common name implies it is an auklet, the Rhinoceros Auklet is more' closely related to the puffins. Rhinoceros Auklets are excellent divers and feed on small fish and cephalopods (Heath 1915, Richardson 1961, Leschner 1976). Rhinoceros Auklets nest primarily in burrows dug into the ground on both forested and un- forested islands. Burrows may be up to 6 meters in length and often fork two or three times before ending in a nesting cavity (Heath 1915, Willett 1915). The recent discovery of Rhinoceros Auklets at Sea Lion Caves, Oregon (Scott et al. 1974, Varoujean and Pitman 1980) and at caves in the conglomerate cliffs at Point Arguello (501 010) indicates that this species may also nest in rocky mainland habitats. Rhinoceros Auklets almost always enter and leave colonies at night when feeding chicks. This predominantly nocturnal behavior may have evolved as a means to reduce kleptoparasitism by gulls. In California and Oregon, Rhinoceros Auklets can often be observed on or near colonies during the day, but farther north they appear to be strictly nocturnal. This difference remains unexplained but may be related to the availability of food and its proximity to the colonies. Despite their diurnal tendencies in California, Rhinoceros Auklet colonies are some of the most difficult to find and census of all colonies of breeding seabirds in the state. CALIFORNIA COLONIES Rhinoceros Auklets are known from eight sites in California, but breeding has been confirmed at only three: Prince Island (325 003), Castle Rock (325 006), and the FaraUon Islands (429 012). At the remaining five sites we have observed Rhinoceros Auklets in breeding plumage on or near the colony and suspect breeding occurs. Small numbers of Rhinoceros Auklets likely occur at several more sites, particularly in northern California. Up to five birds were seen on Green Rock (325 020) at one time and birds were observed entering burrows on several occasions. As many as 38 Rhinoceros Auklets have been seen in the water next to or flying in the vicinity of Green Rock at one time. Rhinoceros Auklets have been suspected to breed at this site for several years (LeValley pers. comm.). At Gualala Point Island (404 004), Fish Rock (404 003), and Arched Rock (404 006), the presence of birds on the water immediately adjacent to the rock or doing "fly-by's", and the presence of suitable burrows, strongly suggests breeding at these sites. Rhinoc- eros Auklets are also suspected to breed at Little River Rock (325 035); (Harris pers. comm.). Point Arguello (501 010) may support a mainland colony of breeding Rhinoceros Auklets in California. We observed a maximum of 24 birds on 1 1 June 1980. A minimum of 13 birds were discovered entering and leaving small caves in the cliffs on 17 and 18 July 1980. An examin- ation of these caves was inconclusive. 50 California Colonies Catalog Total 362 birds • = colony sites 28% Percent of California Breeding Population. Breeding Chronology Noflhfn CalHoroto Firalton lilMidi Cluuti - 1 (38) Incubation Pariod -31-33 d«ys NwMinj P»riod - 36 - 4B day •gg laying hatching '. fledging ■■■ adults pfatant (14,35i Ninabers in parentheses correspond to the references from which ve obtained the data. Channd Island! NotBfMding Mf . I Apr. I May | Jun» | July | Auq. I Sep. | Oct. | Nov. | D^c HISTORICAL STATUS AND VULNERABILITY Rhinoceros Auklets were first found breeding at Castle Rock (325 006) in 1917 when Clay (pers. comm. in Osbome 1972) claimed to have found one nest. Clay, who periodically visited many of the seabird islands in northern California, makes no further mention of this species. Osbome (1972), after his 1969 and 1 970 surveys, estimated a population of between 100 and 150 Rhinoceros Auklets on Castle Rock. He revisited the island in 1977 and felt the population had increased to 200 birds (Osbome pers. comm.). To avoid disturbing the seabirds at Castle Rock we conducted no new groundwork there during this study. Rhinoceros Auklets were known to breed on the Farallon Islands in the early 1800's but disappeared in the 1860's, possibly as a result of collecting by overzealous scientists. They were not observed there again until 1971, and in 1972, two or three pairs were present (Ainley and Lewis 1974). Presently about 100 Rhinoceros Auklets are suspected to breed on the Farallon Islands and the population is thought to be expanding (Ainley pers. comm.). Before 1979, Rhinoceros Auklets were known to nest only as far south as the Farallon Islands. Although our observations at Point Arguello do not constitute a breeding record we are confident that they are breeding there or will do so in the near future. This would represent a range extension of some 350 kilometers. Rhinoceros Auklets are very sensitive to disturbance during the nesting period. Adults will readily desert their nests if disturbed during incubation or brooding. Their burrows are often near the surface of the ground and are easily collapsed. Like all alcids. Rhinoceros Auklets are extremely vulnerable to oil spills. During the breeding season, they concentrate at two sites: Castle Rock and the Farallon Islands. Oil slicks or other pollution in the vicinity of these colonies could affect a large portion of California's breeding population. During winter, CaUfomia waters support large numbers of Rhinoceros Auklets, many from colonies further north (Briggs 1980). The available data indicate an increasing population of Rhinoceros Auklets in CaUfomia. Significant increases in numbers have been ob- served at the two largest colonies in the state, Castle Rock and the Farallon Islands, and Rhinoceros Auklets have been found breeding or are suspected to breed at six additional sites. These recent increases and the discovery of new nesting sites in Oregon (Scott et al. 1974, Varoujean and Pitman, 19791) and British Columbia (Hatler et al. 1978) indicate that this population increase may be widespread along the west coast of North America. SI Tufted Puffin (Lunda cirrhata) Tufted Puffins are among the most abundant and conspicuous of the seabirds in the North Pacific, although they are the least common alcid nesting in California. The species' center of abundance appears to be the western Gulf of Alaska and the Aleutian Islands (Sowls et al. 1978). These colorful, comical seabirds can often be seen standing in front of their nesting burrows, especially in early morning. Tufted Puffins usually nest in earth burrows at the edges of cliffs or on the grassy slopes of islands. Tufted Puffins in California also use burrows or small caves found in loose sandstone or unconsolidated conglomerate rock. In California, extensive areas of ideal nesting habitat exist on only a few islands, so many colonies are small and undoubtedly will remain so. Except on the Farallon Islands, lack of adequate nesting habitat may ultimately be one of the major factors limiting expansion of the Tufted Puffin population in California. Tufted Puffins can sometimes be observed carrying fish in their bills to their chicks at colonies. Preferred foods include small fish, cephalopods, and crustaceans (Hatch et al. 1979). Althou^ Tufted Puffins are diurnal, fledglings apparently leave their burrows and go to sea only imder cover of darkness. In fall, adult puffins lose their brightly colored bill sheathes. Both fledglings and adults head far to sea and during winters are only occasionally seen near land. CALIFORNIA COLONIES Tufted Puffins are found from Prince Island (325 003) in northern California south to Hurricane Point Rocks (454 Oil) at the northern tip of the Big Sur coast. We Ust 14 sites at which Tufted Puffins have been recorded but breeding has been recently documented at only five of these: Prince Island, Castle Rock (325 006), Green Rock (325 020), Puffin Rock (325 021), and the Farallon Islands (429 012). With the exception of Little River Rock (325 035), Tufted Puffins have been observed near burrows at the remaining sites. Although Harris (1974) listed Tufted Puffins as possible breeders on Little River Rock, where the habitat appears suitable for this species, we did not observe birds there. Tufted Puffins were regularly observed at Piedras Blancas Rock (477 007) in 1979 (Rauzon pers. comm.), but not in 1980 (Ron Jameson pers. comm.). The largest Tufted Puffin colonies in California are on Castle Rock and the Farallon Islands. Each contains about 100 birds (Ainley pers. comm. this study). All remaining locations contain ten or fewer birds. Most Tufted Puffin colonies in Califonia have been identified, but a few undocumented pairs may be present at scattered locations, primarily in northemCalifomia. 52 HISTORICAL STATUS AND VULNERABILITY Since the early 1900's, the Tufted Puffin's range in California has contracted northward and its population has declined in size. Tufted Puffins were formerly found breeding in the northern Channel Islands (Willett 1910), but they no longer do so (Hunt et al. 1979). The southernmost suspected breeding location today is Hurricane Point Rocks (454 Oil) in central California. The Farallon Island population of Tufted Puffins was once much larger than it is today. The several thousand birds present in the early 1900's decreased in number to a low of 26 in 1959 (Ainley and Lewis 1974). Ainley and Lewis (1974) state that oil pollution was the major cause of this decline and suggest that the crash of the Pacific Sardine population has been the major factor keeping this population depressed. Elsewhere in California, little information on the historical status of this species is available. Tufted Puffins once nested on Blank Rock (325 024) during the earlier part of this century (Clay impubl. field notes), but they have since disap- peared from this island, probably because of soil erosion. Clay also reported Tufted Puffins on Flatiron Rock (325 023) as "numerous" in 191 1, but since then their nesting habitat has apparently deteriorated greatly. Osborne (1972) found only two Tufted Puffins breeding on Flatiron Rock in 1970 and we list only two on this site during the 1979 and 1980 breeding seasons. Tufted Puffins in California are concentrated around two m^or breeding colonies: Castle Rock and South Farallon Island. Floating oil near either of these islands or repeated human disturbance could be disastrous to the population. Fortimately, both islands are protected, the former as a Nature Conservancy Preserve and the latter as a National Wildlife Refuge. Anyone attempting to land on either island must obtain prior permission. The remain- ing islands are not officially protected, but because of their rugged topography and inaccessibility they have so far received little attention from man. 53 54 Catalog of California Seabird Colonies MAPS & TABLES •• 55 How to Use Maps And Tables A few minutes taken to carefully read this section should make your use of these maps and tables much easier. Each Colony in this report is included on one of 1 1 U.S. Geological Survey maps which cover the Cahfomia coast. An index to these maps appears on the facing page. They are numbered under a U.S. Fish and Wildlife Service system covering the entire United States. The first three digits of the six-digit catalog number for each colony is the map number. All data in the following maps and tables are organ- ized into eleven sections corresponding to these maps. Once you have determined which of these eleven maps covers your area of interest, turn to that section. Heading each section is a map of that area showing the locations of all colonies within that area. The numbers that appear here (001, 002, 003, and so on) are the colony identi- fiers, each specific for a colony area within that map. These are the last three digits of the six- digit catalog number. Note that these numbers are not sequential along the coast. Many new colonies have been identified since catalog num- bers were initially assigned by Varoujean, (1979). We have retained these initial numbers and added new colony numbers as necessary. A sample colony listing is given below. Note that the populations are given in number of breed- ing birds and not pairs. The reference (j, 2, etc.) at the end of each data line corresponds to the proper citation, page 341, from which we obtained the information. If further detail is needed about a site, these sources should be consulted. For information on the archiving of our U.S. Fish and Wildlife Service field notes and photographs see appendix A, page 35 1. Since there are many landforms with similiar or identical names along the coast, such as "Bird Rocks", "White Rocks", or "Castle Rocks", the catalog number is important in distinguishing sites. Therefore we list it after mentioning a site in the text. If you know the name but not the catalog number of a site you are interested in, check appendix C. It lists all colony areas alpha- betically and their catalog numbers. sample ColonyNo. Colony name Lat.-Long. Number breeding birds Investigators Survey date Lcie ^^^/^N / ' V I — :r* — R /^ rSurvi (004) Gull RociO 39°35,'20"N,121°35;45"T? 1 #. -■.-^ .^ /.. , „V- — TV C — r> Pelagic CorKPrawta: Gear lines give the most recent or the best estimates available. Stipple lines give additional estimates for other years. ■ Data qual. ■ see text \ Reference 40 (Nelson & Sowls, 6/14/79, B, II) '42 48 (0sl)ome,6/5/69} y^ 35 Purvey Jj = '"'^' type boat M = from mainland L = o« site 56 MAP INDEX. Dots keyed to map sections. f 57 325 Eureka The maps on the facing page and following page are indexes to the locations of colonies within map 325, Eureka. Note that all colonies on the map are not numbered consecutively from north to south, since many previously unreported colonies have been added since initial colony numbers were assigned by Varoujean (1979). On the pages following these two maps, all colonies are Usted sequentially and a detailed map of each is provided. Numbers of breeding seabirds will vary from year to year, numbers of breeding seabirds within this region. Below are the approximate Fork-tailed Storm-Petrel 350 Leach's Stonn-Petrel 17,000 Brandt's Cormorant 7,000 Double-crested Cormorant 1,000* Pelagic Cormorant 3,000 Black Oystercatcher 100 Western Gull 3,500 Common Murre 250,000 Pigeon Guillemot 2,500 Marbled Murrelet no estimate Cassin's Auklet 3,600 Rhinoceros Auklet 250 Tufted Puffin 150 ♦ coastal population only. 58 325 (North) Eureka r PACIFIC OCEAN N KILOMETERS KIT < wo BIROS lOO - 1.000 BIRDS 1.000 - 10.000 BIRDS MO.eOO - lOO.OOO BIRDS ovcR ioe«aa smos 59 60 325 (South) Eureka N KILOMETERS rcata KEY < 1CX} BtROS 100 - 1.000 BIROS l.OOO - 10.000 BIRDS 10000 - 100,000 BIROS OVER 100,000 BIRDS o ^ €M Sk«t»*r Cev* 61 AREA 325, Eureka (cont'd.) sample ColonyNo. Colony name 004 'Gull Rock^ Pelagic Cormorants /Pelagic Coonorants Lat. -Long. 'Number breeding birds ■ Investigators - Survey date '39°35,'20"N,121°35;45"W 40 (Nelson & Sowls, 6/14/79, B, II) 48 {Osborne, 6/5/69} A Z. Clear lines give the most recent or the best estimates available. Stipple lines give additional estimates for other years. ■ Data qual. - see text r Reference Survey type 42 36 aerial -I B = boat M = from mainland L = on site 001 Cone Rock 41°58'21"N, 124°13'02"W Pelagic Cormorant Western Gull Pigeon Guillemot Total l%Tag1c torfBorant jPelagic Cormorant iiestern Gull ^2- 0 10 _8 18 •20 14 16 (DeGange, Lester & Sowls, 7/2/80, B, I) (DeGange, Lester & Sowls, 7/2/80,8,111) (DeGange, Lester & Sowls, 7/2/80, B, III) (Osborne, 7/16/69 »A) (tester & Rodstrorfi»6/3/?9,B,in) (Osborne, 7/ 16/ 69, A) 42 42 42 35 42 (002) Hunter Rocks ^ Brandt's Cormorant 680 Pelagic Cormorant 122 Black Oystercatcher 2 Western Gull 38 Pigeon Guillemot 120 Total 962 irandt*s ConBorant 320 Brandt's Cormorant 584 Pel^tgic Connorant 50 Pelagic Cormorant 60 Pelagic Cormorant 30 Black Oystercatcher 2 lies tern Gull 30 Itestern Gull 20 tiaeon Guillemot Z 41°57'2?"N, 124°12'41"W (DeGange & Nelson, 7/25/80, A, II) 42 (DeGange, Lester & Sowls, 7/2/80, B, II) 42 (DeGange, Lester & Sowls, 7/2/80, B, III) 42 (DeGange, Lester & Sowls ,7/2/80,8,111) 42 (DeGange, Lester & Sowls, 7/2/80, B, III) 42 C0sb6me,7/24/69Vl) '•"' 35 (Lester, 7/12/79, A, II) 42 (Osborne, 7/24/69,1) 35 (Osborne, 1970) 35 (Lester & Rodstrom, 6/4/79,8,1 1) 42 (Osborne, 6/ 24/69) 35 (Osborne, 7/ 24/69, I) 35 (Lester & Rodstrom,6/4/79,8,II!) 42 (Osborne, 7/24/69,L) ^5 62 AREA 325, Eureka (cont'd.) Section from U.S.G.S. 1 :24,000 scale map: Smith River, Calif. Km Cone Rock Photo by Art Sowls 63 AREA 325, Eureka (cont'd.) 003) Prince Island 41°57'04"N, 124°12'41"W Leach's Storm-Petrel Brandt's Cormorant Double-crested Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Rhinoceros Auklet Tufted Puffin Total Brandt's Cormorant Double-crested Comorarrt Double-crested Conm>raRt Pelagic Cormorant Pelagic Corrrorant Black Oystercatcher Black Oystercatcher Western Gull Western Gull Pigeon Guillewt P = probably present P 0 450 146 6 420 450 12 8 1,492 0 34 180 406 80 40 2 6 100 294 aa DeGange, DeGange, DeGange, DeGange, DeGange, DeGange, DeGange, DeGange, DeGange, Lester Lester Lester Lester Lester Lester Lester Lester Lester Sowls Sowls Sowls Sowls Sowls Sowls Sowls Sowls Sowls ,7/3/80, L) ,7/2/80, BL, II) , 7/2/80, BL, II) ,7/2/80,8, II) , 5/21/80, L, III) ,5/21/80, L, II) ,5/21/80, L, III) .7/3/80, L, III) ,7/3/80, L, III) Osbome»6/17/70,L) Osborne, 6/1 7/70,L) Lester & ffodstrom,6/3/79,l,I) Osborne ,6/1 7/70,1) Lester S fiodstrom,6/3/9,L,n) Osborne,6/17/70,L) tester & Rodstrom,6/3/79,l,ni) Osborne. 6/17/70, L) Lester & Ro<)strom,6/3/?9,L,II) 0sborne»6/l 7/70,1} 42 42 42 42 42 42 42 42 42 35 35 35 42 35 42 35 42 35 42 35 [ OOA ) Smith River was previously assigned a catalog number because of Snowy Plover nesting. We have not ^ ' included information on this species in this report. See Page & Stenzel (1979). rQQc 1 Lake Talawa Beach was previously assigned a catalog number because of Snowy Plover nesting. We iUKJOj jjgyg j,Q, included information on this species in this report. See Page & Stenzel (1979). 64 AREA 325, Eureka (cont'd.) Hunter Rock 002 Prince Island 003 Section from U.S.G.S. 1:24,000 scale map: Smith River, Calif. "o Ship Ashore "~V^ Landing Strif Prince Island Photo by Art Sowls 65 AREA 325, Eureka (cont'd.) 006) Castle Rock 41°45'37"M, 124°15'W Castle Rock is the second most important seabird colony in California. It presently has the largest breeding populations of Common Murres and Rhinoceros Auklets in California as well as important populations of Fork- tailed and Leach's Storm-Petrels, and Tufted Puffins. It is a major hauling area for California sea lions (Zalophm californianus) and Stellers sea lions (Eumetopias jubata) and is a pupping grounds for Harbor seals (Phoca vitulina). Elephant Seals (Mirounga angustirostris) are often present in low numbers. Castle Rock is the primary spring staging grounds for the endangered Aleutian Canada Goose (Branta canadensis leucopareia). The island serves as a safe night roost for the geese as most feeding occurs in nearby fields. Until 1979, Castle Rock was privately owned and in the 1920's sheep grazed its slopes. Speculators have contemplated guano mining, rock quarrying, and construction of a tourist attraction on the island. Fortunately, in 1979, the Nature Conservancy purchased Castle Rock and it will soon be protected as a refuge by the U.S. Fish and Wildlife Service. See Appendix B. Fork-tailed Storm-Petrel 100 Leach's Storm-Petrel 5,000 Brandt's Cormorant 2,200 Pelagic Cormorant 340 Black Oystercatcher 6 Western Gull 1,350 , Common Murre 126,000^ Pigeon Guillemot 800 Cassin's Auklet 3,600 Rhinoceros Auklet 200+ Tufted Puffin 100 Total 139,596 Brandt's Cormorant 1,758 Brandt's Cormorant 2,010 Pelagic Cormorant 100 Pelagic Cormorant 96 Black Oystercatcher 2 Black Oystercatcher 2 Western Gull 1,200 Cojfflwn Hurre 80,000 Cassin's Auklet 100 Rhinoceros Auklet Cassin's Auklet Rhinoceros Auklet 100- Tufted Puffin /I Estimate is number of birds present X X ■150 50 Osborne, 1970, L) 35 Osborne, 1970, L) 35 DeGange & Nelson, 7/25/80, A, II) 42 Lester, Nakagawa & Vasey, 6/19/80, B, III) 42 Lester, Nakagawa & Vasey, 6/19/80,8, III) 42 Lester & Rodstrom,7/12/79,A,&7/19/79,A,III) 42 Lester & Rodstrom,7/12/79,A,&7/19/79,A,III) 42 Lester, Nakagawa & Vasey, 6/19/80,8, III) 42 Osborne, 1970, L) 35 Osborne, 1977, L) 34 Lester, 1980, BL, III) 42 (Osborne, 1 970, L) 35 (Lester & Rodstrom,7/12/79,A&7/19/79,A,III) 42 (Osborne, 1970,L) 35 (Lester & Rodstrom, 5/21/79, 8,111) 42 (Osborne, 1970, L) 35 (Lester & Rodstrom, 5/21/ 79, 8,111) 42 (Osborne, 1970, L) 35 (Osborne, 1970,L) 35 (Thoresen,4/16 &8/25/59,L) 4i (Clay, 1917, L) 35 (Clay, 5/20/34, L) 35 (Osborne, 1970, L) 35 (Osborne, 1970,L) 35 times 1.67, sec page 10. Briggs et al.'s estimate for 7/2/80 aerial survey (also times 1.67 J is 131,600 007) "Tolowa Rocks" 41°45'15"N, 124°14'W Fork-tailed Storm-Petrel Leach's Storm-Petrel Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total Pelagic Comorant Pelagic Cormorant Western Gull 60 92 8 116 40 316 24 36 24 (Lester, 6/20/80, L, III) 42 (Lester, 6/20/80, L) 42 (Lester, 6/19&6/20/80,B, II) 42 (Lester, 6/19&6/20/80,BL, II) 42 (Lester, 6/19&6/20/80,BL, II) 42 (Lester, 6/19&6/20/80,BL, III) 42 (Osborne, 9/14/70,K,census of one rock) 35 (Lester S Rodstrom,5/21/79,B,I) 42 (Lester & Rodstrom,5/21/79,8,II) 42 66 AREA 325, Eureka (cont'd.) Castle Rock Photo by Gary Lester 67 AREA 325, Eureka (cont'd.) 008) White Rock 41°44'46"N, 124°13'44"W Black Oystercatcher Western Gull Pigeon Guillemot Total Hack Oystercatcher Black Oystercatcher Western Gull Western Gull v.040^'4^l4^^'vXMW/^uM. ' 2 (Lester & Berner, 6/20/80,1,1) 74 (Lester & Berner, 6/20/80, L, II) 10^ (Lester & Rodstrom, 5/21/79, B, III) 86 1 (Osborne, 7/ 17/69,1) 2 (Lester & Rodstrom,5/21/79,B,III) 40 (Osborne, 7/1 7/69,1) 24 (Lester & Rodstrom,5/21/79,B,n) 42 42 42 35 42 35 42 009) Sister Rocks 41°39'29"N, 124°08'47"W Brandt's Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Common Murre Pigeon Guillemot Total ^■iffffat's Cormorant Brandt's Conrorant Pelagic Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot 42 22 2 40 50 40 196 100 8 20 14 2 4 40 DeGange & Nelson, 7/25/80, A, II) Berner & Lester, 6/20/80, B, II) Berner & Lester, 6/20/80, B, III) Berner & Lester, 6/20/80,8, III) Berner & Lester, 6/20/80,8, III) Berner & Lester, 6/20/80,8, III) OS borne, 7/69, H) DeGange & Lester, 5/22/79, 8, I I) OS borne, 7/ 69, M) DeGange & Lester, 5/22/79, 8, 11) DeGange & Lester, 5/22/793, HI) OeGange & Lester, 5/22/79,8,11) DeSange & Lester, 5/22/79,8,1! I) 42 42 42 42 42 42 35 42 35 42 42 42 42 68 AREA 325, Eureka (cont'd.) e)\ (009V fnf,f\ *- \ V 26J/; \ '***•' \ 4 \ * \ : \ '^ Midway Point ^ •\ • 'X- ••> • • • w 06 0 J Ed Q 2b 1 36 /: \ 124*10' Sister — ■ Rocks Section from U.S.G.S. 1:24,000 scale map: Sister Rocks, Calif. Kb 0 H 1 69 AKtA jzo, tureKa icont a.) 010) False Klamath Rock 41°35'40"N, 124°06'36"W 356 84 110 80 ,500 160 n Brandt's Cormorant Double-crested Cormorant Pelagic Cormorant Western Gull Common Murre 26 Pigeon Guillemot Total 27,290 Brandt's Cormcirant; 370 Brandt's Conrsirant 406 Double-crested Connorant 12 Double-crested Connorant 2 Pelagic Cormorant 18 Pelagic Cormorant 44 Western Gull 50 Western Gull 80 Common Hurre 20,000 Pigeon Guillemot X ^ Estimate is number of birds present times 1.67 survey (also times 1.67) is 37,600. Berner & Lester, 6/20/80,8, III) 42 Berner & Lester, 6/20/80,8, III) 42 Berner & Lester, 6/20/80,8, III) 42 Berner & Lester, 6/20/80,8, III) 42 Lester, 6/19&7/12/79, A, III) 42 Berner & Lester, 6/20/80,8, III) 42 mbomeJn/JQ.m 35 Lester & Rodstrc»ii,6/19&7/12/79,A,III) 42 Osborne,! 970, M) 35 DeGapige & Lester, 5/22/79,8,111) 42 Osborne,! 970, W) 35 DeGange & Lester, 5/22/79, 8,111) 42 Osborne, !970,H) 35 OeGange & Lester, 5/22/79. 8,111) 42 Osborne,! 970, H) 35 Osborne,! 970, W) 35 see page 10. Briggs et al.'s estimate for 7/2/80 aerial (on) Flint Rock Head 4r31'31"N, 124°05'00"W Pelagic Cormorant 4 (Osborne, 8/6/69, M) 35 012) White Rock 41°30'56"N, 124°05'06"W White Rock is one of the most important Brown PeUcan roosts in northern Cahfomia, with up to 1,000 birds present from August through October. Brandt's Cormorant 240 Double-crested Cormorant 60 Pelagic Cormorant 12 Black Oystercatcher 2 Western Gull 24 Pigeon Guillemot 6 Total ^ ^ 344 lras^'l-^limcbP«ll '''''• ■" 206 8paERrant 78 Double-crested Cormorant 120 Pelagic Cormorant 10-20 Pelagic Conuorant 8 Black Oystercatcher 2 Western Sull 50-60 Western Gull 62 Western Gull 84 ffester« Gull ^^sMmm^ 60 Pigeon Sulllecsot .^^^p; 30-40 P = probably present (Harris, 1965-72, L) 24 (Harris, 1965-72, L) 24 (Lester & Stewart, 6/23/80,6, III) 42 (Lester & Stewart, 6/23/80,8, II) 42 (Lester & Stewart, 6/23/80,8, III) 42 (Lester & Stewart, 6/23/80,8, III) 42 (Lester, McKay & Rodstrom, 8/1/79,8, III) 42 (Harris, 1965-72, L) 24 (Harris,1965-72,L) 24 (Ha*'ris,«/8/?4,l) 23 (HarHs, 6/1/77,1) 23 (Lester, HcKay& Rodstrom»S/1/79,B, IV) 42 (HarHs,1965-72,L) 24 (tester, HcKay & Rods tr«r!,8/1/79, 8,11) 42 (Harris, 1965-72,1) 24 (Harris, 1965-72, I) 24 (Harris, 6/8/74,1) 23 (HarHs,6/V77.l) 23 (Lester, McK^ S Rodstrom,8/l/79,8,ItI> i 42 (Harris, 1965-72,1) * ; 24 84 AREA 325, Eureka (cont'd.) 026 n Pilot -U Rock Section from U.S.G.S. 1:24,000 scale map: Trinidad & Crannel, Calif. Km 035 Little RJwfi*JVJ?'^' '\^' 1.: f,.: Moonsl little River Rock Photo by Art Sowls 85 AREA 325, Eureka (cont'd.) 036 Clam Beach was previously assigned a catalog number because of Snowy Plover nesting. We have not included information on this species in this report. See Page & Stenzel (1979). 037 "Mad River" was previously assigned a catalog number because of Snowy Plover nesting. We have not included information on this species in this report. See Page & Stenzel (1979). 038) Old Areata Wharf 40°50'59"N, 124°05'58"W Double-crested Cormorant 340 mP^^trested Cormorant 32? fiouble-crested Cormorant 352 Double-crested Cormorant 424 Caspian Tern X X = present (Sowls & Stewart, 6/19/80, B, III) (Ayers,1971) (Ayers,1972) (Ayers,5/i5/73) (Harri 5,6/16/66) 42 5 5 5 23 %u^ H^^s^^ 1 BS^^.>*^>5?.^' ^-^ "^'"^ ^^^^^^^^^^^^^^^W^^^^^^»s^ - JW Double-crested Cormorants, Old Areata Wharf Photo by Art Sowls 86 AREA 325, Eureka (cont'd.) B)racut r Trailer 87 AREA 325, Eureka (cont'd.) 039 Humboldt Bay was previously assigned a catalog number because of Snowy Plover nesting. We have not included information on this species in this report. See Page & Stenzel (1979). 040) False Cape Rocks 40°30'38"N, 124°23'40"W (Lester & Sowls, 7/23/80, A, II) (Lester & Rodstrom, 7/26/79,8, II) (Lester & Rodstrom, 7/26/79,8, III) ttu -.(Lester & Rodstrom, 7/26/79, 8, III) 8,000^(Lester & Rodstrom, 8/2/79, A, II) (Lester & Rodstrom, 7/26/79, 8, III) (0sbofne,7/69»A) (Lester & Rod5trom,8/2/79,A,n) (Osborne, 7/69, A) (Osborne, 7/69, a) (Osborne, 7/69, A) (Qsfesnme,7/69,A) 8randt's Cormorant 400 Pelagic Cormorant 170 Black Oystercatcher 2 Western Gull 220, Coirmon Mu rre 8,000^ Pigeon Guillemot 150 Total 8,942 Brandt's Connorant 406+ Brandt's Cormorant 640 Pelagic Connorant P Vtestem Gull X Coffln»n Murre 1,6(KJ Piqmn Sufllemot X 42 42 42 42 42 42 35 42 35 35 35 35 X = present, P = probably present n Estimate is number of birds present times 1.67, see page ID. Briggs et al.'s estimate for 7/2/80 aerial survey (also times 1.67) is 11,000. 88 AREA 325, Eureka (cont'd.) Section from U.S.G.S. 1:24,000 scale map: Femdale, Calif. Km I »- Mussel' Rock '. Rock 40°30' ...5^, ° ■ ' " False, ^ False Cape • Qg &9 AREA 325, Eureka (cont'd.) @ Sugarloaf Island 40°26'18"N, 124^24'41"W Osborne, 1970, LM) Osborne, 1970, LM) Osborne, 1969- 70, LM) Nelson & Sowls, 7/26/79,6, III) Nelson & Sowls, 7/26/79,8, III) Nelson & Sowls, 7/26/79,6, III) Lester & Rodstroni,5/10/79,M,III) Nelson & Sowls, 7/26/79,8, II I) Nelson & Sowls, 7/26/79,6,11 1) Nelson & Sowls, 7/26/79,8) Osborne,! 969. IM) Nelson & Sowls, 7/26/79, 6,111) Osborne, 1969-70,LM) Os borne, 1969- 70, LM) Osborne, 19 70, LM) Os borne, 1 970, LM) 6randt's Cormorant 200 ( Double-crested Cormorant 32 ( Pelagic Cormorant 400 ( Black Oystercatcher 6 ( Western Gull 320 ( Pigeon Guillemot 240 ( Tufted Puffin 4 ( Total 1,202 ^^nnorant (unid.) 100 ( Brandt's Cormorant 182 ( Doufale-crested Cormorant ■? ( Double-Crested Cormorant 6 ( Pelagic Cormorant 21{H- { Black Oystercatcher X ( Western Gull 300 { Pigeon Guillemot 200 ( Tufted Puffin 4 ( 35 35 35 42 42 42 42 42 42 42 35 42 35 35 35 35 X = present 042) Steamboat Rock 40°24'54"N, 124°24'09"W Brandt's Cormorant Pelagic Cormorant Western Gull Common Mu rre Pigeon Guillemot Total Brandt's Connorant Brandt's Cormorant Pelagic Corrrorant Western Gull Common Murre 494 (Lester & Sowls, 7/23/80, A, II) 42 0 (Lester, Nelson, Rodstrom & Sowls, 7/26/79,6, II) 42 60 -,( Lester, Nelson, Rodstrom & Sowls,7/26/79,B,III) 42 4,500 ^(Lester & Rodstrom, 7/24/79, A, Lester, Nelson, 42 Rodstrom & Sowls, 7/26/79, 6, III) 42 , 2 (Lester, Nelson, Rodstrom & Sowls,7/26/79,6,III) 42 ^Toss" 340 {Osborne, 1969- 70 »AH) 640 (Lester & Rodstrom,7/24/79,A, Lester, Nelson, Rodstrom & Sowls, 7/26/ 79,8, II) 4 (Osborne, 1969- 70, AM) X (Osborne, 1969-70, AM) 600 (Osborne, 196 9- 70, AM) Zli Estimate is number of birds present times 1.67, see page 10. Briggs et al.'s estimate for 7/2/80 aerial survey (also times 1 .67) is 5,100. 90 AREA 325, Eureka (cont'd.) i 91 043) Sea Lion Rock 40°19'35"N, 124°21 '38"W Cormorant (unid. ) Western Gull Total 0 (Nelson & Rods trom, 7/18/79,6) 2 (Nelson & Rodstrom, 7/18/79,8, III) 42 42 35 [OH) Point St. George Lighthouse 4r50'N, 124°22'W Pelagic Cormorant 12 (Lester, 7/12/79, A, III) No detailed map available see page 59. 42 (045 "Whaler Island", unnamed rocks. Brandt's Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total ^rk-tifTS§i'*SfiWSfitret Leach's Storm-Petrel Fork-tailed Storm-Petref leach's Storm-Petrel Black Oystercatcher Western (kill Hgeon Guillemot Cassin's Auklet 40 2 4 24 72 142 X X 20,000 X X X f Crescent City breakwater. Steamboat Rock and 41°45'N, 124°13'W. (Berner & Lester, 6/20/80,8, III) (Berner & Lester, 6/20/80,8, I) (Berner & Lester, 6/20/80, BL, III) (Berner & Lester, 6/20/80, BL, III) (Berner & Lester, 6/20/80, BLM, III) (CTaly,5/14/t6&7939,L;Ta1madge, early 1^30's) (Clay, 5/14/16&1939,L;Talmadge, early 1930's) (Howell, 7/ 16/19,1) (Talmadge, early 1930's) (Talmadge, early 1930's) (Howell, 7/16/n,L) (Clay, 3/22/25,1) 42 42 42 42 42 35 35 35 35 35 35 35 046) Unnamed Small Rocks 41°42'N, 124°08'W Double-crested Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total Double-crested Cormorant Pelagic Connorant Black Oystercatcher Vtestem <5u11 X » present, P = probably preKtit 22 (Berner 66 (Berner 6 (Berner 28 (Berner 100 (Berner 222 2 (DeGange 6 ( Defiance P {DeGange 8 (O^sange & Lester, 6/20/80,8, II) & Lester, 6/20/80,8, II) & Lester, 6/20/80, B, III) & Lester, 6/20/80,8, III) & Lester, 6/20/80,8, III) % Lestosr, & Lester, s'm'mWJ i Lester, 5/22/793) & Lester. 6/e2/?M» II) 42 42 42 42 42 92 AREA 325, Eureka (cont d.) iWhite Rock Section from U.S.G.S, 1:24,000 scale map: Slater Rocks, Calif. Kb Section from U.S.G.S. 1:2A,000 scale map: Sister Rocks, Calif. Kn 1 h — •— \ ,^^az -^^a-" ':**- { I (I \ :•<' ( I r 1 "o > /' " 'n \ A, \ \ // « -- l^JI^VJi: ' ■. '--I?— --V- ^ — ■"" 7^ 11 '• 7 93 AREA 32b, fcureka (cont d.) (047) "Easy Triangle Rocks" 41°40'22"N, 124°08'30"W Pelagic Cormorant 54 (Berner & Lester, 6/20/80,8, II) 42 Black Oystercatcher 2 (Berner & Lester, 6/20/80,8, III) 42 Western Gull 8 (Berner & Lester, 6/20/80,8, III) 42 Pigeon Guillemot 20 (Berner & Lester, 6/20/80,8, III) 42 Total 84 Pelagic Cormorant 20 (DeGange & Lester, 5/ 22/79, 8,1!) 42 Black Oystercatcher P (DeGange & lester,5/22/79,B,III) 42 Western Gull 12 (OeGange & Lester, 5/22/79,8, II) 42 Pigeon GuHlewt 10 ^ f^^^^9iAtotoM^S^IIifciill««.. 42 P = probably present 048) "Rock R" 41°40'00"N, 124°08'30"W Brandt's Cormorant Pelagic Cormorant Western Gull Pigeon Guillemot Total irandt's Cormorant Pelagic Cormorant Ulack Oystercatcher (DeGange & Nelson, 7/25/80, A, II) (Berner & Lester, 6/20/80, 8, II) (Berner & Lester, 6/20/80,8, III) (Berner & Lester, 6/20/80,8, III) ( LestM'B^l 9*7/ 1 2/ 79 ,%rf' (DeGange & Lester, 5/22/79, 8,1) :>^(De6ange & Lester, 5/22/79,8,111) 140 10 4 2 156 188 4 42 42 42 42 42 ^2 42 049) "Last Chance Rock" 4r38'05"N, 124°07'30"W Double-crested Cormorant 4 Pelagic Cormorant 40 Western Gull _4 Total 48 Pelagic Cormorant 6 stern Gull 2 (Berner & Lester, 6/20/80,8, II) (Berner & Lester, 6/20/80, 8, II) (Berner & Lester, 6/20/80,6, III) (DeSange B. Lester, 5/22/79, B, II) (DeGange & Lester, 5/22/79,8, II) 42 42 42 42 42 050) Footsteps Rock 41°37'00"N, 124°07'10"W Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total Pelagic Cormorant Black Oystercatcher Pigeon Guillemot 36 (Berner & 2 (Berner & 4 (Berner & 60 (Berner & 102 20 (DeGange S Lester, 5/22/79,8, I) 2 (DeGange & Lester,5/22/79,B,III) 50 (DeGange & Lester, 5/22/79,8^111) Lester, 6/20/80, 8, II) Lester, 6/20/80, 8, III) Lester, 6/20/80,8, II) Lester, 6/20/80.8, III) 42 42 42 42 42 42 42 94 AREA 325, Eureka (cont'd.) Section from U.S.G.S. 1:24,000 scale map: Chllds Hill, Calif. Kn 049 Section from U.S.G.S. 1:24,000 scale map: Requa, Calif. Kb t » 95 AREA 325, Eureka (cont'd.) 051) "Radar Station Rocks" 41°33'30"N. 124°06'00"W Double-crested Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total 20 34 P X 20 74 (Lester & Rodstrom, 6/5/79, B, III) (Lester & Rodstrom, 6/5/79, B, II) (Lester & Rodstrom, 6/5/79, B) (Lester & Rodstrom, 6/5/79, B) (Lester & Rodstrom, 6/5/79, B, III) 42 42 42 42 42 X " present, P = probably present (052) Palmer's Point to Scotty Point (except 017) 41°07'N, 124°09'W Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total Pelagic Connorant Black Oystercatcher Western Gull Pigeon Suitlenjot 100 (Lester 10 (Lester 20 (Lester 40 (Lester 170 14S (Lester, 6 (iester. 20 (Lester, 50 (Lester, & Stewart, 6/ 23/80, B, II) & Stewart, 6/23/80, B, III) & Stewart, 6/23/80, B, III) & Stewart, 6/23/80, B, III) mKay % Rddstroin,8/1 /79,B,rr) McKay & RodstroiB.8/l/79,B,ni) HcKay S RodstroM/V?9,B,in) McKay & Rotestern 5u11 Jiseon Juillefflot X = present X (Osborne 1,640 (Lester, 22 (Lester 10 (Lester 22 (Lester 60 (Lester 1,754 , 1969-70, L) Sowls & Stewart, 1980, BL, III) & Stewart, 6/23/80, B, II) & Stewart, 6/23/80, BL, III) & Stewart, 6/23/80, BL, III) & Stewart, 6/23/80, BL, III) $2 (Osfaorrm 56 (Lester, 2 (Osborne 2 (Lester, X (Osborne 12 (Lester, 20 (Osborne »I96< »1969-70a: McKay & Rodstr<«n,8/ 1/79,8,11) ,1969-70, L) McKay & Rods trom, 8/ 1/79. 8,111) ,1969-70.L) HcKay & Rodstroni,8/l/79,B,ni) .1969-70,1) 35 42 42 42 42 42 35 35 42 35 42 35 42 35 100 AREA 325, Eureka (cont'd.) 101 AREA 325, Eureka (cont'd.) 055) Three Brothers & Hair Seal Rocks 40°19'40"N, 124°21'58"W Brandt's Cormorant Pelagic Cormorant Western Gull Total 110 6 4 120 (Nelson & Rodstrom, 7/18/79. B, II) (Nelson & Rodstrom, 7/18/79, B, I) (Nelson & Rodstrom, 7/18/79,8, III) 42 42 42 056) "Cormorant Hotel" 40°02'10"N, 124°04'50"W Pelagic Cormorant Western Gull Total 280 2 282 (Lester, Nelson, Rodstrom & Sowls, 7/18/79, MB, II) 42 (Lester, Nelson, Rodstrom & Sowls, 7/18/79, MB, I) 42 102 AREA 325, Eureka (cont'd.) ♦three t^Ci'tl^'' Brothers ^*'s> RcitC Section from U.S.G.S. 1:24,000 scale map: Petrolla, Calif. Sea Lion Rock 0 42°02'30"-k 12A°05' ^ 056 Section from U.S.G.S. 1:24,000 scale map: Shelter Cove, Calif. Km Sewage Dis 103 AREA 325, Eureka (cont'd.) 057) Point St. George 41°47'N. 124°15'W Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total 14 8 20 40 82 (Berner & Lester, 6/20/80, B, I) (Berner & Lester, 6/20/80, B, III) (Berner & Lester, 6/20/80, B, III ) (Berner & Lester,6/20/80,B,II.I) 42 42 42 42 Pelagic Cormorant Black Oystercatcher Western Gull Total 058) Wilson Rock 4r35'45"N, 124°06'37"W 2 (Berner & Lester, 6/20/80,8, II) 2 (Berner & Lester, 6/20/80,8, III) _8 (Berner & Lester, 6/20/80,8, III) 12 42 42 42 104 AREA 325, Eureka (cont'd.) Section from U.S.G.S, 1:24,000 scale map: Cresent City, Calif. Km % Brown Rock SAND DUNES 105 379 Ukiah The map on the facing page is an index to the locations of colonies within map 379, Ukiah. Note that all colonies on the map are not numbered consecutively from north to south, since many previously unreported colonies have been added since initial colony numbers were assigned by Varoujean (1979). On the pages following this map, all colonies are listed sequentially and a detailed map of each is provided. Numbers of breeding seabirds will vary from year to year, numbers of breeding seabirds within this region. Below are the approximate Brandt's Cormorant , 6,000 Pelagic Cormorant 4,000 Black Oystercatcher 70 Western Gull 500 Common Murre. 6,000 Pigeon Guillemot 1,000 Marbled Murrelet no estimate Rhinoceros Auklet . . . ' p Tufted Puffin 10 106 379 Ukiah fe^ gl (Cj^ (oo.) o (030j ^^S "lQ ©f^^>A \ ^ @v 1 ,, €r K 107 sample Colony No. - Colony name [004) 'Gull Rock^ Pelagic Cormorants •Number breeding birds Lat.-Long. / y- Investigators f *i — ^^ r Survey date ^9°35,'20"N,121°35;45"lf f fT. ^ -v, r 40 (Nelson & Sowls ,6/14/79,6,1 1 48 (0sbome,6/5/69) Qear lines give the most recent or the best estimates available. Staple lines give additional estimates for other years. .Survey type - B M L • Data qual. - sec text T Reference 42 35 aerial boat from mainland on site ® Brandt's Cormorant 0 Pelagic Cormorant 250 Black Oystercatcher 2 Western Gull 10 Pigeon Guillemot 20 Total 282 Brandt's Corfnorant X X = present "Rockport Rocks" 39°44'10"N, 123^50'00"W (Lester & Rodstrom, 6/12/79, B, II) (Lester & Rodstrom, 6/12/79,6, III) (Lester & Sowls, 7/19/79,8, III) (Lester & Sowls, 7/19/79,6, III) (Lester & Rodstrom, 6/12/79,8, III) (Osborne, 8/26/69 .H) 42 42 42 42 42 36 (002) Cape Vizcaino Brandt's Cormorant 3,080 Pelagic Cormorant 120 Western Gull 60 Common Murre 5,800 Pigeon Guillemot 8 Total 9,068 Brandt's Cormorant 1,000 Brandt's Cormorant 3.662 Pelagic Comorant 50 Western Gull 40 39°43'34"N, 123°49'55"W (Lester & Sowls, 7/23/80, A, II) 42 (Lester & Rodstrom, 6/12/79,6, III) 42 (Lester & Rodstrom, 6/12/79,6, III) 42 (Briggs & Lewis, 5/7/80, A,I II) 42 (Lester, Sowls & Stewart,7/12/80,M,III) 42 (Osborne, 8/26/69,H) 36 (Lester & Rodstrom, 8/2/79.A, III) 42 (Osborne, 8/26/ 69, M) 36 (Osborne, 8/26/69, H) 36 108 AREA 379, Ukiah (cont'd.) Section from U.S.G.S. 1:2A,000 scale map: Westport, Calif. BCape Vizcaino % \*' ^•^; Cape Vizcaino Photo by Gary Lester 109 AREA 379, Ukiah (cont'd.) Pelagic Cormorant Western Gull Total Pelagic Corinorant 003) Chris Rocks 39°42'51"N, 123°48'07"W 54 (Lester & Sowls, 7/19/79, B, II) _6 (Lester & Sowls, 7/19/79,8, III) 60 40 (Osborne, 8/25/69 »M) 42 36 Chris Rock Pliuto by Tim Osborne Brandt's Cormorant Pelagic Cormorant Western Gull Total Brandt's Cormorant Brandt's Cormorant, 004) Kibesillah Rock 39°34'49"N, 123'^46'51"W 350 (Lester & Sowls, 7/23/80, A, II ) 92 (Lester & Rodstrom, 6/12/79,8, III ) 20 (Lester & Rodstrom, 6/12/79,8) 462 150 (Osborne, 8/26/69, M) 490 (Lester & Ro I I 123*>47'30" _|_ 39035 » o» (ooa)- Rock 4} ^ ::i Section from U.S.G.S. 1:24,000 scale map: Inglenook, Calif. Kb .h^^^ Kibesillah Rock Photo by Gary Lester 111 AREA 379, Ukiah (cont'd.) 006) Goat Island Area 39 18'28"N, 123 48'49"W Brandt's Cormorant 1,240 Pelagic Cormorant 134 Black Oystercatcher 6 Western Gull 2 Pigeon Guillemot 120 Tufted Puffin 4 Total 1,506 Brandt *s Cormorant 500 Brandt's Cormorant ■ 1,400 Pelagic Contiorant 30 Pelagic Carmorant 38 Black Oystercatcher 2 Black Oystercatcher 2 Vfestern Gull 24 Pigeon Guillemot 12 Lester & Sowls, 7/23/80, A, II) 42 Lester & Sowls, 6/5/80, BM, II) 42 DeGange & Lester & Nelson, 6/5/80, BL, III) 42 DeGange & Lester & Nelson, 6/5/80, BL, II) 42 Sowls, 6/5/80, BM, III) 42 DeGange, Nelson & Sowls, LM, II) 42 Osborne, 8/26/69,1) ' 36 Lester & Rodstrom,8/2/79,A,n!} 42 Osborne, 8/26/69, L) 36 Lester & Rodstrom, 6/21/79, 8,111) 42 Osborne, 8/26/69,1) i 36 Rodstrom,5/17/79,M,III) i 42 Lester & Rodstrom,6/21/79,8,III ) 1 42 (Lester & Rodstrom, 6/21/79, B,!II) I 42 Main nesting island ("a" on map). Photo by Gary Lester 12 AREA 379, Ukiah (cont'd.) Section from U.S.G.! 1:24,000 scale map: Mendocino, Calif. Kb 113 AREA 379, Ukiah (cont'd.) 007) "Devil's Basin" 39°10'14"N, 123°44'50"W Brandt's Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total Brandt 's Ciiirorant Brandt's Connorant Pelagic Comwrant Pelagic Connorant Western Gull Western Gull X = present 300 (Lester 1 132 (Lester, 2 (Nelson, 14 (Lester, 20 (Lester, 468 350 (Osborrtfi 380 (Lester ■ 70 { Osborne 52 (Lester . X (Osborne 6 ,,.(Les,|er,j & Sowls, 7/23/80, A, III) 42 Sowls & Stewart, 7/12/80,6, II) 42 Sowls & Stewart, 6/6/80,8, II) 42 Sowls & Stewart, 7/12/80, B, III) 42 Sowls & Stewart, 7/12/80,8, III) 42 \i^mmm ' 36 & Rodstroet,8/2/79.A,ni) 42 ,8/25/69 ,H) 36 & R«tic Comjorantt Slack Oystercatcher Hgeon Guillemot Iiim4. Puffin , .. 26 (DeGange, Nelson & Stewart, 6/5/80,8,11) 42 2 (Lester, Sowls & Stewart, 6/6/80, BL, III) 42 140 (Lester & Rodstrom, 5/18/79, BL, III) 42 120 (DeGange, Lester & Nelson, 6/5/80, BL, III) 42 2 (Lester, Sowls & Stewart, 6/6/80, L, II) 42 290 56 (Lester & Rods trom,5/ 18/79,61,11) 42 2 (Lester & Rodstrom,5/18/79,BL, III) 42 30 (tester & Rodstrom,5/18/79,BLJII) 42 A (Lester & R O Section from U.S.G.S. 1:2A,000 scale map: Mallo Creek, Calif. Km 139 AREA 379, Ukiah (cont'd.) 032) "333 Point" 39°05'N, 123°42'30"W Brandt's Cormorant Pelagic Cormorant Black Oystercatcher Total Brandt's Cormorant 360 100 2 462 (Lester & Sowls, 7/23/80, A, II) (Lester & Rodstrom, 6/22/79,8, III) (Lester & Rodstrom, 6/22/79,8, III) 42 42 42 0 (Lester & Rodstrom,6/22/79,B,a/ ■I) 42 033) Bridgeport Landing 39°03'45"N, 123°4r50"W (Lester & Rodstrom, 6/22/79,8, III) (Lester & Rodstrom, 6/22/79, 8,111) Pelagic Cormorant 16 Western Gull 2 Total 18 42 42 034) Mallo Pass Creek 39°02'20"N, 123°4r50"W Pelagic Cormorant Western Gull Pigeon Guillemot Total 20 (Lester & Rodstrom, 6/22/79,8, III) 4 (Lester & Rodstrom, 6/22/79, 8, II) 20 (Lester & Rodstrom, 6/22/79, 8, III) 44 42 42 42 140 AREA 379, Ukiah (cont'd.) Section from U.S.G.S. 1:24,000 scale map: Mallo Creek, Calif. 123*>42'30" 39°02'30"-4- Sectlon from U.S.G.S, 1:24,000 scale map: Mallo Creek, Calif. Km I- 141 404 Santa Rosa The map on the facing page is an index to the locations of colonies within map 404, Santa Rosa. Note that all colonies on the map are not numbered consecutively from north to south, since many previously unreported colonies have been added since initial colony numbers were assigned by Varoujean (1979). On the pages following this map, all colonics are listed sequentially and a detailed map of each is provided. Numbers of breeding seabirds will vary from year to year to year. Below are the approx- imate numbers of breeding seabirds within this region. Leach's Storm-Petrel 100 Ashy Storm-Petrel •.".'.".'!!! .14 Brandt's Cormorant. . '.'.'. k 000 Double-crested Cormorant . . . .'lOO* Pelagic Cormorant ' " 4 qoO Black Oystercatcher .".'.".'* ' 60 Western Gull .*!!.'. 1 100 Pigeon Guillemot • • • • .^'^^^ Marbled Murrelet .■:::; no'estimate Rhinoceros Auklet ... 20 Tufted Puffin .'.'.'.".*." ! .' .' .* ." jo * coasta/ population only. 142 404 Santa Rosa Point Arena or Bay 0--^ .Fort Ross Bodega Bay n KitOMETERS KEY < 100 BIROS 100 1.000 BIRDS VOOO 10.000 BIROS 10000 - 100.000 BIRDS OVER 100.000 BIRDS 143 AREA 404. Santa Rosa (cont'd.) Colony name -i sample Colony No. - Pelagic Cormorants /Pelagic Cofworants 004 Gull Rock' Lat. -Long. ■Number breeding birds ■ Investigators T- Survey date 39°35,'20"N,12r35;45"W' 40 (Nelson & Sow1s,6/14/79;b,I I ) 48 (0sborr»e,6/5/69) Z. Clear lines give the most recent or the best estimates available. Stipple lines give additional estimates for other years. ■ Data qual. - see text \ Reference 42 35 type „ A = aerial ^"'^'■■y J B = h„at M = from mainland L = on site [OOU Sea Lion Rocks Pelagic Cormorant 6 Black Oystercatcher 2 Western Gull 2 Pigeon Guillemot 60 Total 70 Pelagic Cormorant 40 Western Gull P fl^on ^niernot I 38°55'07"N, 123^43'45"W (Lester & Rodstrom, 5/31/79,8, III ) (Lester & Rodstrom, 5/31/79, B, III) (Lester & Rodstrom,5/31/79,B,III ) (Lester & Rodstrom, 5/31/79, B, III) (0sborne.8/25/69,M) . {Osborne, 8/25/69 ,H) imi)^rnt,a/25/69,M) 42 42 42 42 36 36 36 f = pri)habh present 002) "Iverson Landing" 38°50'39"N, 123°38'37"W (Lester, Sowls & Stewart, 7/13/80, B, II ) (Lester, Sowls & Stewart, 7/13/80,8, III ) (Lester, Sowls & Stewart, 7/13/80, B, III) Pelagic Cormorant 96 Black Oystercatcher 4 Pigeon Guillemot 30 Total 130 Pelagic Coraoraftt m Pelagic Corawrant T08 (0sbornt,8/2S^«9,M) (Lester a Rodstrom, 5/ 31/ 79, 8,11) 42 42 42 36 42 144 AREA 404, Santa Rosa (cont'd.) Section from U.S.G.S. 1:24,000 scale map: Point Arena, Calif. Km I I I T 13 N T 12 N 72 Pt Arena Latitude Saunders ' Reef 020 Saunders LandinK*, (002 Section from U.S.G.S. 1:24,000 scale map: Saunders Reef, Calif. Km Iversen Landing 145 AREA 404, Santa Rosa (cont'd.) 003) Fish Rocks 38°48'00"N, 123°35'3T'W The Fish Rocks colonies are some of the most important seabird colonies along the northern coast of California. They are inhabited by a great diversity of seabirds and are also important hauling areas for California sea lions and Harbor seals. Leach's Storm-Petrel 100 ( Brandt's Cormorant 18 ( Pelagic Cormorant 400 ( Black Oystercatcher 4 ( Western Gull 350 ( Pigeon Guillemot 250 ( Rhinoceros Auklet 14 ( Tufted Puffin 4 ( Total 1,130 ifandt's Corrrarant 30 ( Pelagic Corinorant 200 ( Pelagic Cormorant 200 { Black Oystercatcher 2 ( Western Gull TOO ( ii#fe»:siy|Miti6fe 6 ( DeGange, Lester & Stewart, 1980, L, III) 42 Lester, Nelson & Sowls,6/7/80,BL,II ) 42 Lester, Nelson, Sowls & Stewart, 1980, B, II) 42 Lester & Rodstrom, 5/31/79, BL, III) 42 Lester & Rodstrom,5/31/79,BL,III ) 42 Nelson, Sowls & Stewart, 6/7/80, B, III) 42 Nelson, Sowls & Stewart, 6/7/80, B, III) 42 DeGange, Lester & Nelson, 6/7/80, BL, II) 42 Lester & Rodstrom, 5/31/79, BL,III) 42 Osborne, 8/27/69, B) 36 Lester & Rodstrom, 5/ 31/ 79,81,11 1) 42 DeGange, Lester & Nelson,6/7/80,BL,III) 42 Osborne, 8/27/69, 8) 36 Osborne, 8/27/69 3) - 36 Pelagic Cormorant. Fish Rocks Photo by Bill Rodstrom 146 AREA 404, Santa Rosa (cont'd.) Section from U.S.G.S. 1:24,000 scale map: Onalala, Calif. o ♦ * Collins Landing ^ 147 AREA 404, Santa Rosa (cont'd.) 004) Gualala Point Island 38°45'04"N, 123°3T42"W Brandt's Cormorant Western Gull Pigeon Guillemot Total Brandt's Csmorant Brandt's Connorant Western G^ll 1,240 (Lester & Sowls, 7/23/80, A, II) 40 (DeGange,6/n/80,M,III) 40 (Lester, Sowls & Stewart, 7/13/80,8, III) 1,320 500 (Osborne. 8/27/69. «) 1,840 (Lester & Rodstrom,8/2/79,A,in) 40 (Lester & Rodstrom,6/24/79,B,III) 42 42 42 36 42 42 Gualala Point Island Photo by Gary Lester 0051 "Russian River Rocks" 38°27'14"N, 123°08'34"W (Lester & Rodstrom,6/25/79,B,II) (Lester & Rodstrom, 6/25/79,8, III) (Lester & Rodstrom, 6/25/79, B, II) (Lester & Rodstrom, 6/25/79,8, III) (Lester & Rodstrom, 6/25/79,8, III) (Osborne, 8/23/69.H) Brandt's Cormorant 124 Double-crested Cormorant 32 Pelagic Cormorant 88 Western Gull 64 Pigeon Guillemot 40 Total 348 Pelagic Cormorant zm 42 42 42 42 42 36 148 AREA 404, Santa Rosa (cont'd.) Gualala Point* Gualala Pt lsland*ti^pf* .Rocks Section from U.S.G.S. 1:24,000 scale map: Arched Rock & Duncan* Mills, Calif. Kn I — -♦ Arched^— »*^ Rock 149 AREA 404, Santa Rosa (cont'd.) Brandt's Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Tufted Puffin „ Jptal franit's Cormorant Brandt's Cormorant Mestern GuH 006) Arched Rock 38°25'53"N, 123°07'32"W 0 (Lester & Sowls,7/23/80,A,I) 2 (Lester & Rodstrom, 6/25/79,8, III) 60 (Lester & Rodstrom, 6/25/79,8, III) 20 (Lester & Rodstrom, 6/25/79, 8, III) 2 (Lester & Rodstrom, 6/25/ 79,8, III) ~M T50 (Osborne, 17B?lf,M) 400 (Lester & Rodstrom,6/25/79. 8,111) 6 (0sborne,8/23/69,M) 42 42 42 42 42 36 42 36 007 Salmon ("reek was previously assigned a catalog number because of Snowy Plover nesting. We have not included information on this species in this report. Sec Page & Stenzel ( 1 979). 008) Bodega Rock 38''17'48"N, 123"02'50"W Brandt's Cormorant 1,350 Black Oystercatcher 2 Western Gull 50 Total 1,402 Brandt's Cormorant 800 Brandt's Cormorant 1,350 Brandt's Cormorant 1,714 (Nelson & Sowls, 6/24/80, A, II) (Osborne, 8/23/69, L) (Lester & Rodstrom, 6/25/79, B, III) (0sborne,8/23/59,L) (Jurek, 6/15/72, A. II) (Le^,t€X.>&.„ftodstrom,7iLU7^,A,{i}^., 42 36 42 36 12 42 Bodega Rock Photo by Jay Nelson 150 AREA 404, Santa Rosa (cont'd.) 151 AREA 404, Santa Rosa (cont'd.) 009 "Dillon Beach Rocks" 38°16'26"N, 122°59'11"W Brandt's Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total Ifelagic Cormorant ll-Fandt's Cormorant 190 (Lester & Sowls, 7/23/80, A, II) 186 (Lester & Rodstrom, 6/26/79, B, 11) 6 (Lester & Rodstrom, 6/26/79, B, III) 12 (Lester & Rodstrom, 6/26/79, B, III) 40 (Lester & Rodstrom, 6/26/79, B, III) 434 250 (Osborne, 8/23/ 69 ,M) 168 (Lester & Rodstrc»ii^|^|i:,n> 42 42 J2 42 42 36 42 152 AREA 404, Santa Rosa (cont'd.) 153 AREA 404, Santa Rosa (cont'd.) 010) Bird Rock 38°13'49"N, 122°59'35"W Ashy Storm-Petrel 14 ( Pelagic Cormorant 8 ( Black Oystercatcher 2 ( Western Gull 228 ( Pigeon Guillemot 30 ( Total 282 Ashy Storm-PetreT 10 ( Pelagic Cormorant 2 { Black Oystercatcher ■6 { Western Gull 60 ( Pigeon Guillemot 24 ( Lester & Rodstrom, 7/1/79, L, II) Lester & Rodstrom, 7/1/79, L, II) Lester & Rodstrom, 7/1/79, L, III) Lester & Rodstrom, 7/1/79, L, III) Lester & Rodstrom,7/l/79,L,III) Ainley & Osborne, 7/3/72,1) Osborne, 8/23/69,8) Ainley & Osborne, 7/3/ 72, I) Ainley & Osborne, 7/3/ 72,1) Ainley & Osborne, 7/ 3/ 72. L) 42 42 42 42 42 3 36 3 3 3 Pelagic Cormorant Western Gull Pigeon Guillemot Total Pelagic Cormorant Oil) Tomales Point 38°12'13"N, 122°57'39"W 134 (Lester & Rodstrom, 7/1/79, B, III) 2 (Lester & Rodstrom, 7/1/79, B, III) _^ (Ainley & Whitt, 7/3/72,8) 144 172 (Ainley & Whitt, 7/3/72. B) ' ^ ''" 42 42 3 (012 Point Reyes Beach was previously assigned a catalog number because of" Snowy Plover nesting, have not included information on this species in this report. See Page & Stenzel (1979). We 013 Limantour Estero was previously assigned a catalog number because of Snowy Plover nesting. We have not included information on this species in this report. See Page & Stenzel (1979). 154 AREA 404, Santa Rosa (cont'd.) Section from U.S.G.S. 1:24,000 scale map: Tomales, Calif. 155 AREA 404, Santa Rosa (cont'd.) f m /I A Napa River was previously assigned a catalog number because of Double-crested Cormorant, California lU I 4 J Clapper Rail, and Caspian Tern nesting. We have not included information on this site because it is not coastal. See Varoujean (1979). [015) Petaluma River was previously assigned a catalog number because of California Clapper Rail nesting. We have not included information on this species in this report. Sec Gould (1973). [01 6) GaUinas Creek was previously assigned a catalog number because of California Clapper Rail nesting. We have not included information on this species in this report. See Gould (1973). 017) Point Arena 38°57'20"N, 123°44'30"W Pelagic Cormorant Black Oystercatcher Pigeon Guillemot Total 28 (Lester, 5/23/79, M, II) 2 (Lester, 5/23/79, M, III) 60 (Lester, 5/23/79, M, III) 90 42 42 42 mis) "Moat Cove" 38°53'10"N, 123°4TW Pelagic Cormorant 40 (Lester & Rodstrom, 5/31/79, B, III) 42 (019) "Section 30 Cove" 38°52'39"N, 123°40'10"W Pigeon Guillemot 30 (Lester & Rodstrom, 5/31/79,8, III) 42 156 AREA 404, Santa Rosa (cont'd.) Point Arena^ Section from U.S.G.S. 1:24,000 scale map: Point Arena, Calif. Section from U.S.G.S. I^ 1:24,000 8cal6 map: Point Arena, Calif. Ka 157 ARJEA 404, Santa Rosa (cont'd.) 020) Saunders Landing 38°51'13"N, 123°39'05"W Pelagic Cormorant Pigeon Guillemot Total Pelagic Comwrant 174 (Lester, Sowls & Stewart, 7/13/80, II) 42 2 (Lester & Rodstrom, 5/31/79,6, III) 42 176 48 (lesler & R6dstrom,5/31/79,B,iII) 42 021) Triplett Gulch 38°49'N, 123°36'15"W Pelagic Cormorant Black Oystercatcher Pigeon Guillemot ,„ Total 390 2 200 592 (Lester, Sowls & Stewart, 6/6/80,8,11) 42 (Lester, Sowls & Stewart, 6/6/80, B, III) 42 (Lester, Sowls & Stewart, 6/6/80, B, III) 42 (Lester & Rodstrom, 5/31/ 79,8,111) 42 022) "Fish Rock Cove" 38°47'45"N, 123°35'20"W Brandt's Cormorant Pelagic Cormorant Total felagic Corttwrant 18 (Lester, Sowls & Stewart, 7/13/80,6, II) 42 54 (Lester, Sowls & Stewart,// 13/80,6,11) 42 72 36 (Lester S Rods trom, 5/31/79,6, I I) 42 158 AREA 404, Santa Rosa (cont'd. Saunders Reef Section from U.S.G.S. 1:24,000 scale map: Saunders Reef, Calif. Section from U.S.G.S. 1:24,000 scale map: Gualala, Calif. 159 AREA 404, Santa Rosa (cont'd.) 023) Collins Landing to Gualala River 38°46'N, 123°32'40"W Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total f Pelagic Cormorant i; Black Oystercatcher 368 6 2 30 We 154 2 (Lester, Sowls & Stewart, 7/13/80,6, II) 42 (Lester, Sowls & Stewart,7/13/80,B,III) 42 (Lester, Sowls & Stewart, 7/13/80,8, III) 42 (Lester, Sowls & Stewart, 7/13/80,8, III) 42 (Lester & Ro r. I" ^^jv^j-jV- Salmon Creel 175 AREA 404, Santa Rosa (cont'd.) 038) Bodega Head 38°18'N, 123°03'45"W Pelagic Cormorant 168 (Lester & Rodstrom, 6/25/79, B, II) 42 Black Oystercatcher 6 (Lester & Rodstrom, 6/25/79,8, III) 42 Pigeon Guillemot _60 (Lester & Rodstrom, 6/25/79, 8,111) 42 Total 234 176 AREA 404, Santa Rosa (cont'd.) Section from U.S.G.S. 1:2A,000 scale map: Bodega Head, Calif. ^ Sodega Rock • 'a -|-38Ol7'30" 123°02'30" 177 AREA 404, Santa Rosa (cont'd.) 039) Pinnacle Rock 38°18'20"N, 123°0T10"W Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total 4 2 2 30 38 (Lester & Rodstrom, 6/26/79,8, II) (Lester & Rodstrom, 6/26/79,3, III) (Lester & Rodstrom, 6/26/79, 8, II) (Lester & Rodstrom, 6/26/79,8, III) 42 42 42 42 040 'Sonoma-Marin County Line" 38°17'20"N, 123°00'20"W (Lester & Sowls,7/23/80,A,II) 42 (Lester & Rodstrom, 6/26/79, 8, II) 42 (Lester & Rodstrom, 6/26/79, 8,111) 42 (Lester & Rodstrom, 6/26/79, 8, III) 42 (Lester & Rodstrom, 6/26/79, 8, III) 42 Brandt's Cormorant 12 ( Pelagic Cormorant 134 ( Black Oystercatcher 4 ( Western Gull 16 ( Pigeon Guillemot 40 Total 206 ® "Elephant Rock Complex" 38°11'N, 122°58'W Pelagic Cormorant Pigeon Guillemot Total 16 li 28 (Lester & Rodstrom, 7/1/79, 8, III) (Lester & Rodstrom, 7/1/79, 8, III) 42 42 178 AREA 404, Santa Rosa (cont'd.) Section from U.S.C.S. 1:2A,000 scale map: Bodega Head, Calif. Km I I I Section from U.S.G.S, 1:24,000 scale map: Valley Ford, Calif. Km I I I .,^ ~** Section from U.S.G.S. 1:24,000 scale map: Tomales , Calif. 179 429 San Francisco The map on the facing page is an index to the locations of colonies within map 545, San Francisco. Note that all colonies on the map are not numbered consecutively from north to south, since many previously unreported colonies have been added since initial colony numbers were assigned by Varoujean (1979). On the pages following this map, all colonies are listed sequentially and a detailed map of each is provided. Numbers of breeding seabirds will vary from year to year. Below are the approximate numbers of breeding seabirds within this region. Most of these birds are at the Farallon Islands (429 012). Leach's Storm-Petrel 1,400 Ashy Storm-Petrel 4,000 Brandt's Cormorant 31,000 Double-crested Cormorant 2,000* Pelagic Cormorant 4,000 Black Oystercatcher 100 Western Gull 34,000 Common Murre 100,000 Pigeon Guillemot 4,500 Marbled Murrelet X Cassin's Auklet 105,000 Rhinoceros Auklet 100 Tufted Puffin 100 * coastal population only. X = present 180 429 San hrancisco N KILOMCTERS KEY < 100 BIRDS 100 - 1 000 BIROS 1,000 - 10.000 BIROS 10.000 - 100.000 BtRDS OVER 100.000 BIROS o > 181 AREA 429, San Francisco (cont'd.) sample ColonyNo. Colony name (004) \ Gull Rock Pelagic Cormorants Lat. -Long. '39°35,'20"N,12r35;45"W / f. ^ Number breeding birdi Investigators - Survey date \ r 40 (Nelson & Sowls, 6/14/79,8,1 1 ) 48 {0sbome,6/5/69} i_ Clear lines give the most recent or the best estimates available. Stipple lines give additional estimates for other years. Survey type ■ Data qua!. ■ see text \ Reference 42 35 A = aerial B = hnar M = from mainland L = on site @ Point Reyes 37°59'26"N, 123°59'24"W (Lester & Rodstrom, 7/1/79,6,7/11/79, AM, III) 42 (Lester & Rodstrom,7/l/79,B,7/n/79,M,III ) 42 (Lester & Rodstrom, 7/1/79, B, 7/11/79, M, III ) 42 (Lester & Rodstrom, 7/1/79,8, 7/11/79, M, III) 42 KLester & Rodstrom, 7/1/79, 8,7/11/79, AM, III) 42 (Lester & Rodstrom, 7/1/79,8, 7/11/79, M, III) 42 (LeValley, 1975-80, L) 32 (Ainley & Wh1tt,?/3/72,8) J (Ainley & Wh1tt,7/3/72,8) 3 (Alnley & Whitt,7/3/72,B) 3 (Afnley & WhHt,7/3/72,B) 3 (Ainley & Wh1tt, 7/3/72, B) 3 (Ainley & S^1tt , 7/3/ 72 , B ) 3 ^ Estimate is number of birds present times 1.67, see page 10. Briggs et al.'s estimate for 7/2/80 aerial survey (also times 1.67) is 22,000. Brandt's Cormorant 2,400 Pelagic Cormorant 808 Black Oystercatcher 10 Western Gull 62 Common Murre 16,500 Pigeon Guillemot 120 Tufted Puffin 6 Total 19,906 Brandt's Comorant 96Q Pelagic Cormorant 528 Black Oystercatcher 6 Western Gull 26 Conimon Murre 7,640 PIseon^auiUfijuQ^;: 48 182 AREA 429, San Francisco (cont'd.) 183 AREA 429, San Francisco (cont'd.) 002) Millers Point Rocks 37"58'53"N, 122"48'35"W Brandt' Pelagic Western Pigeon Tota ;Srandt' Brandt' Pelagic s Cormorant Cormorant Gull Guillemot 1 s Cormorant s ComiQrant Cormorant 194 (Nelson & Sowls, 6/24/80, A,III) 60 (Lester & Rodstrom, 7/2/79,6,11) 34 (Lester & Rodstrom, 7/2/79, B, III) 10 (Lester & Rodstrom, 7/2/79, B, III) 298 120 (Uster & R0d$t«jfn»7/2/79,8,7/11/79,A,ni) 30 , (Osborne, 1§70,«) 10 (Osborne. 1970, «) 42 42 42 42 42 36 36 003) Double Point Rocks 37°56'51"N, 122°47'08"W Brandt's Cormorant 258 Pelagic Cormorant 16 Black Oystercatcher 2 Western Gull 13,000^ Common Murre Pigeon Guillemot 40 Total 13,340 Brandt's Cormorant 340 Western Gull 100 i^mmiMime , U400 /I Estimate is number of birds present times 1.67 survey (also times 1.67) is 13,900. (Lester & Rodstrom, 7/2/79, 6,7/11/79, A, III) 42 (Lester & Rodstrom, 7/2/79, 6, II) 42 (Osborne, 1970, M) 36 (Lester & Rodstrom, 7/2/79, 6, III) 42 (Nelson & Sowls, 6/24/80, A, III) 42 (Lester & Rodstrom, 7/2/79, B, III) 42 (Osborne, 1970,M) 36 (Osborne, 1970, M) 36 ( Osborne. 1 970 ,H) . 36 see page 10. Briggs et al.'s estimate for 7/1/80 aerial (004 BoUnas Lagoon was previously assigned a catalog number because of Snowy Plover nesting. We have not mcluded mformation on this species in this report. See Page & Stenzel (1979). (005 San Pablo Creek was previously assigned a catalog number because of California Clapper Rail nesting. We have not inlcuded information on this species in this report. See Gould (1973). (006 nr,iL^w"K Marsh was previously assigned a catalog number because of California Clapper Rail nestmg. We have not mcluded mformation on this species in this report. See Gould (1973). 184 AREA 429, San Francisco (cont'd.) Section from U.S.G.S. 1:24,000 scale map: Doable Point, Calif. 37^7 '30" 122»47'30 Section from U.S.G.S. 1:24,000 scale map: Double Point, Calif. 185 AREA 429, San Francisco (cont'd.) 007) Bird Island 37°49'27"N, 122°32*09"W Brandt's Cormorant Western Gull Pigeon Guillemot Total Brandt's Cemorant Pigeon Guillemot 0 2 4 6 75 2 (Lester & Rodstrom, 7/3/79, B, I) (Lester & Rodstrom, 7/3/79, B, II) (Lester & Rodstrom, 7/3/79, B, III) (Osborfte,8/1W69,M) (0sborn€,8/19/69,M} 42 42 42 36 36 008) Point Bonita 37°48'55"N, 122^31 '40"W Pelagic Cormorant Western Gull Pigeon Guillemot Total Pelagic CornKirant X = present 60 4 J(_ 64 50 (Lester & Rodstrom, 7/3/79, B, II) (Lester & Rodstrom, 7/3/79, B, II ) (Lester & Rodstrom, 7/3/79,8) (Reynolds, 8/1 9/69, M) 42 42 42 009) Seal Rocks 37°46'42"N, 122''30'53"W The Seal Rocks colony is an excellent location to see seabirds, partic- ularly Brown Pelicans, even though there are few nesting birds here. Calit'ornia Sea Uons can also be observed. See appendix B. Brandt's Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total ..._.,,„._, Brandt ' s Wilrant Western Gull 0 2 44 _6 52 76 24 (Nelson & Sowls,6/24/80,A,I ) 42 (Nelson & Nelson, 5/25/79, M, 7/1/79, B, II) 42 (Nelson & Nelson, 5/25/79, M, 7/1/79, B, III) 42 (Nelson & Nelson, 5/25/79, M, 7/1/79, B, III) 42 (Nelson & Nelson, 5/2S/79,M, 7/1/79, B, iff) 42 (Reynolds »7/21/70»M) 36 010) Alameda Naval Air Station 37"47'12"N, 122^19'49"W No map is provided for this site in San Francisco Bay. For the most current information contact the California Department of Fish and Game. Least Terns are an endangered species. Populations of Least Terns are surveyed annually. Least Tern Least Tern Least Tern 80 ( ,1979,L) 160 (EHc*fiM»n978,l) ^^— ^' 90 (Atwood et al.. 5/6/77,1) vl'W.v^*^,.^ S*^,XvX■ ^♦'^' 12 12 12 186 AREA 429, San Francisco (cont'd.) (Sir) §dp( ' 37«47'30" 122*32 '30" Section from U.S.G.S. 1:24,000 scale map: Point B«nlta, Calif. Km T /•: ,< \ C/^ \' V) '' Mile Rock 029 / — / Lands ErtdJ r " X ft i( .( 1'Os.*-' ' Point Lobos/ al \ / Rocks 'j'J -A. 'i\,w-iiMd 's^Ps 187 AREA 429, San Francisco (cont'd.) on) Oakland International Airport 37°43'21"N, 122°13'46' No map is provided for this site in San Francisco Bay. For the most current information contact the California Department of Fish and Game. Least Terns are an endangered species. Populations of Least Terns are surveyed annually. Least Tern 0 (Ericl \ \ \ \ \ \ -N- \ [012) \ \ MIDDIEFARAILON \ \ \ aVi'A ' 2 SCALE IN MILES \MAINT0P ISLAND t" \ SOUTHEAST FARAUON / .Ns > \0«KUNO y S»NfR»NCISCOV_ 1 FARALLON \ ^^ N.W.R. SAN JOSE 0 510 » 30 40 scileia nlles 189 AREA 429, San Francisco (cont'd.) Southeast Farallon Island U.S.F.W.S. photo 190 AREA 429, San Francisco (cont'd.) Southeast Farallon Island Photo by Bill Parsons 191 AREA 429, San Francisco (cont'd.) 013) San Pedro Rock 37°35'43"N, 122°3T20"W Brandt's Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total Cormorant (unidJ) 0 8 2 8 40 B8 (Nelson, Sowls & (Nelson, Sowls & (Nelson, Sowls & (Nelson, Sowls & (Nelson, Sowls & Stuart, 6/9/79, BL, I) Stuart, 6/9/79, BL, I) Stuart, 6/9/79, BL, II) Stuart, 6/9/79, BL, I) Stuart, 6/9/79, BL, III) str i^^miM^f/ziiWM^ n. 42 42 42 42 42 36 014) Devil's Slide Rock 37°34'28"N, 122°3r39"W Brandt's Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Common Mu rre Pigeon Guillemot Total ^mmn Hurre Jigeon GuHleitiot /]^ Estimate is number of birds present survey (also times 1.67) is 2,9001 22 (Nelson, Sowls & Stuart, 6/9/79, B,6/30/79,M, II) 42 180 (Nelson, Sowls & Stuart, 6/9/79, B,6/30/79,M, III) 42 4 (Nelson, Sowls & Stuart, 6/9/79, B, 6/30/79, M, II) 42 2 , (Nelson, Sowls & Stuart, 6/9/79, B, 6/30/79, M, II) 42 2,300^(Nelson & Sowls, 6/30/79, M, 7/6/79, A, III) 42 120 (Nelson, Sowls & Stuart, 6/9/79, B, 6/30/79, M, III) 42 2,628 700 2 times 1.67, see page JO, Biiggs et al.'s estimate for 7/1/80 aerial (Reynolds, 7/21/70,M) (Reynolds, 7/21 /70,M) 36 36 (ois) Alameda Creek 37°36'59"N,122°07'20"W No map is provided for this site in San Francisco Bay. Forster's Tern 200 (Sibley, 5/28/48) 43 016) Bair Island 37°31'43"N, 122°13'05"W No map is provided for this site in San Francisco Bay, For the most current information contact the California Department of Fish and Game. Least Terns are an endangered species. Populations of Least Terns are surveyed annually. Least Tern Least Tern 8 (Erickson, 1979, L) 2 (Atwood et al., 5-6/77) 12 12 017) Coyote Hills 37°32'48"N, 122°07'28"W No map is provided for this site in San Francisco Bay. For the most current information contact the California Department of Fish and Game. Least Terns are an endangered species. Populations of Least Terns are surveyed annually. Forster's Tern Least Tern Total 614 (Gill, 4-8/71) 80 (Gil 1.4-8/71) 694 43 43 192 AREA 429, San Francisco (cont'd.) 193 4 S '-«!♦*' AREA 429, San Francisco (cont'd.) Greco Island was previously assigned a catalog number because of California Clapper Rail and Snowy [018) Plover nesting. We have not included data on these species in this report. Sec Gill (1972) and Page Stenzel(1979). (019) Coyote Creek 37°28'4T'N, 122°02'5T'W No map is provided for this site in San Francisco Bay. Tor further information see Gill (1972). Caspian Tern 400 (Gill ,4-8/71 ) ^^ {020J Guadalupe Slouqh 37°28'12"N, 122°04'52"W No map is provided for this site in San 1 rancisco Bay. 1 or further information sec Gill (1972). Forster's Tern 1,256 (Gill ,4-8/71 ) ^^ i021 ) Pescadero Creek was previously assigned a catalog number because of Snowy Plover nesting. We have not included information on this species in this report. See Page & Stenzel (1979). 022) Punta del Ano Nuevo 37°07'07"N, 122°20'09"W Pelagic Cormorant 210 (Lester & Nelson, 6/13/80,8, II) 42 Pigeon Guillemot _70 (Lester & Nelson, 6/13/80,8, III) 42 Total 280 Pelagic Cormorant 200 (Nelson i Lester, 7/5/79, Btin) 42 0231 Ano Nuevo Island 37°06'30"N, 122°20'09"W Pelagic Cormorant 10 (Briggs,1976,L) 43 Black Oystercatcher 24 (Briggs,1976,L) 43 Western Gull 240 (Briggs,1976,L) 43 Pigeon Guillemot _64 (Briggs,1976,L) « Total 338 I 04 AREA 429, San Francisco (cont'd.) Pelagic Cormorants, Punta deJ Aiio Nuevo Photo by Art Sowls 195 AREA 429, San Francisco (cont'd.) 024 Point Resistance 37°59'55"N, 122°49'40"W Brandt's Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Common Murre Pigeon Guillemot Total Corniron Kurre 150 (Rodstrom, 7/11/79, A, III) 104 (Lester & Rodstrom, 7/2/79,6,11) 2 (Lester & Rodstrom, 7/2/79, B, III) 20,, (Lester & Rodstrom, 7/2/79, B, III) 7,500^(Nelson & Sowls, 6/24/80, A, III) 60 (Lester & Rodstrom, 7/2/79, B, III) 7,836 400 (Osborne, 1970,M) ^J Estimate is number of birds present times 1.67, see page 20. Briggs et al.'s estimate for 7/1/80 aerial survey (also times 1.67) is 6,800. 42 42 42 4? 42 42 36 Point Resistance Rock Photo by Jay Nelson 025) Gull Rock Area 37°52'35"N, 122°37'W Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total 28 2 4 _2 36 (Lester & Rodstrom, 7/3/79, B, II) (Lester & Rodstrom, 7/3/79, B, III) (Lester & Rodstrom, 7/3/79, B, III) (Lester & Rodstrom, 7/3/79, B, III) 42 42 42 42 AREA 429, San Francisco (cont'd.) "X" (?esistanci Section from U.S.G.S, 1:24,000 scale map: Double Point, Calif. Km Section from U.S.G.S. 1:24,000 scale map: 5«a KAfa*l & Ft. BoBita, Calif. Km I ' I 37"52'30''-|- 122°37'30 197 AREA 429, San Francisco (cont'd.) 026) Muir Beach Headlands to Tennessee Cove 37°5T00"N, 122°33'45"W Pelagic Cormorant Black Oystercatcher Pigeon Guillemot Total 34 2 36 (Lester & Rodstrom, 7/3/79,8, II) (Lester & Rodstrom,7/3/79,B,II) (Lester & Rodstrom, 7/3/79, B, II) ^2 42 42 027) Bonita Cove 37°49'30"N, 122°31'W Pelagic Cormorant 20 Western Gull 2 Pigeon Guillemot X Total 22 (Lester & Rodstrom,7/3/79,B,II ) (Lester & Rodstrom, 7/3/79, B, I) (Lester & Rodstrom, 7/3/79, B) 42 42 42 X = present 198 AREA 429, San Francisco (cont'd.) Section from U.S.G.S. 1:24,000 scale map: ?t. Bonlta, Calif. Section from U.S.G.S. 1 : 24, 000 scale map: Pt. Bonlta, Calif. 199 AREA 429, San Francisco (cont'd.) 028) Point Diablo Bluffs and Needles 37°49'30"N, 122°29'W (Lester & Rodstrom, 7/3/79, B, II) 42 (Lester & Rodstrom, 7/3/79, B, II) 42 (Lester & Rodstrom, 7/3/79, B) 42 Pelagic Cormorant 64 Western Gull 16 Pigeon Guillemot X Total 80 X = present 029) Lobos Rock and Lands End 37°47'15"N, 122°30'20"W Brandt's Cormorant Western Gull Pigeon Guillemot Total ISrandt's Comrarant 80 12 68 160 0 (Nelson & Sowls, 6/24/80, A, II) (Nelson & Nelson, 7/1/79, B, III) (Nelson & Nelson, 7/1/79,8, III) (Nelson & Nelson; 7/1 /79»8, I) 42 42 42 42 42 Lobos Rock Photo by Jay Nelson 200 AREA 429, San Francisco (cont'd.) Needles Section from U.S.G.S. 1:24,000 scale map: San Francisco North & Pt. B«alta, Calif. Km I ' I 201 AREA 429, San Francisco (cont'd.) 030) Pillar Point 37°23'N, 122°29'55"W Pelagic Cormorant Pigeon Guillemot Total Pelagic Connorant 16 (Nelson, Sowls & Stuart, 6/9/79, B,I I ) _6 (Nelson, Sowls & Stuart, 6/9/79, B, III) 22 0 (Reynolds, 1970) 42 42 36 202 Mricrt tz.^, i>an rrancisco tcont a.) 203 AREA 429, San Francisco (cont'd.) 031) Eel Rock Cliffs 37°24'15"N, 122°25'30"W Pelagic Cormorant Pigeon Guillemot Total Pelagic Cormorant 12 (Lester & Nelson, 6/13/80, B, I) 42 _P (Nelson, Sowls & Stuart, 6/9/79, B) 42 12 14 (Nelson, Sowls & Stuart, 6/9/79,8.11) ^2 032) Seal Rock Cliffs 37°23'N, 122''25'W Brandt's Cormorant Pelagic Cormorant Black Oystercatcher Pigeon Guillemot Total t*e1agfc Cbntsjrant Black Oystercatcher ;Pigeon Guillemot P = probably present A ««.^^ *» WK ^.Jo*'^*' 50 (Lester & Nelson, 6/13/80, B, II) 108 (Lester & Nelson, 6/1 3/80, B, II ) 4 (Lester & Nelson, 6/13/80, B, III) 10 (Lester & Nelson, 6/1 3/80, B, II) 172 168 {Nelson, Sowls & Stuart, 6/9/79, 8, 1 1) P (Nelson, Sowls & Stuart, 6/9/79, 8) 10 (Nelson, Sowls & Stuart, 6/9/79,8, III) 42 42 4? 42 42 42 42 033) Martins Beach 37°22'N, 122°24'30"W Brandt's Cormorant 40 Pelagic Cormorant 100 Black Oystercatcher 2 Pigeon Guillemot 120 Total 262 Pelagic Cornwrant 152 Black Oystercatcher 2 (Lester & Nelson, 6/13/80, B, II) (Lester & Nelson, 6/13/80, B, II) (Lester & Nelson, 6/13/80,8, III) (Lester & Nelson, 6/13/80,8, III) (Nelson & Lester,7/5/79.B,ir) (Nelson & Lester, 7/5/79,8, III) 42 42 42 42 42 42 204 AREA 429, San Francisco (cont'd.) Eel Rock^ :rom U.S.G.S, scale map: Half Moon Bay & Gregorlo, Calif. Km ' I 205 AREA 429, San Francisco (cont'd.) 034) Pigeon Point 37°10'55"N, 122°23'20"W Black Oystercatcher 2 (Lester & Nelson,7/5/79,BM,I ) 42 Pigeon Guillemot 6 (Lester & Nelson,'7/5/79,BM,III) 42 Total 8 [035j Greyhound Rock 37°04'40"N, 122°16'W to Davenport 37°00'30"N 122°ir30"W No map is provided for this site as it extends along a lengtliy stretch of coastline. Brandt's Cormorant 236^(Nelson, 7/14/80, M, II) ^^ Pelagic Cormorant 50 (Lester & Nelson, 7/5/79, B, II) ^^ Black Oystercatcher 6 (Lester & Nelson, 7/5/79, B, IV) ^2 Pigeon Guillemot 400 (Lester & Nelson, 7/5/79, B, III) ^2 Total 682 n all on pier at Davenport. 206 AREA 429, San Francisco (cont'd.) Section from U.S.G.S. 1 : 24, 000 scale map: Pigeon Point, Calif. Km 207 AREA 429, San Francisco (cont'd.) 036 Alcatraz Island 37°49'34"N, 122°25'20"W Western Gull X (Abbore, 1980) is Heermann's Gull 2 (Binford, 1980) 8 [037) Pier 45 37°48'34'N, 122°25'W Western Gull X (Danielson, 1973) 15 (038) Verba Buena Island 37°48'34"N> 122°22'15'W Western Gull 80 (Cogswell ,7/28/74) 15 %iUm euii X (Cdfiiitfiiigr) 15 X = present 208 AREA 429, San Francisco (cont'd.) Arch Rock .Alcatraz\lsland / ghtn^use j \ / 7- Sectlon from U.S.G.S. 1:24,000 scale map: San Francisco North, caif. Km ■ 1 ' Blossom Rock 0«U.«Dd West, Calif. 209 AREA 429, San Francisco (cont'd.) 039) Red Rock 37°55'45"N, 122°25' 50"W Western Gull 92+ (Cogswell, 5/20/70, L) 25 X (Cogswell, 1960, 1969, 1971, 1975, 1978) 25 040) The Brothers 37°57'47"N, 122°26'W Western Gull Western Gull 80 (Cogswell, 6/22/67, M) X (CQgswelU1968-7U1973J975-76) 15 m- 15 X = present ® (041) The Sisters 37°59'22" N, 122°26'25" Western Gull 40+ (Cogswell ,6/13/75) 15 210 AREA 429, San Francisco (cont'd.) > \ Section from U.S.G.S. 1:2A,000 scale map: ' San Quentln, Calif. Km H -\ 0 / " Stipple lines give additional estimates for other years. boat M = from mainland L = on site ( nm J ^Uder Creek was previously assigned a catalog number because of Snowy Plover nesting. We have not \^J included information on this species in this report. See Page & Stenzel (1979). [ nn?l ^*J*''o River was previously assigned a catalog number because of Snowy Plover nesting. We have not [ UVC) jjjgiudgd information on this species in this report. See Page & Stenzel (1979). 003) Elkhorn Slough 36°49'04"N, 121°46'30"W Western Gull Forster's Tern Caspian Tern Total Western Sul1 Western Sull Western Gull Forster's Tern Forster's Tern Caspian Tern Caspian Tern 122 95 180 397 .....,..,......„.,.^^... 110 102 165 550-600 170 160-180 (Harvey, 1980, L) (Harvey, 1980, L) (Harvey, 1980, L) (farou3ean et a1. ,5-g/1972,L) (Harvey, 1978, L) (Harvey, 1979, L) (Harvey, 1978, L) (Harvey, 5/25/79, L) (Harvey, 1978,L) (Harvey. 1979, I) 26 26 26 43 26 26 26 26 26 26 fnn4l Salinas River Beach was previously assigned a catalog number because of Snowy Plover nesting. We [ UUH ; jj^yg ^^^ included information on this species in this report. See Page & Stenzel (1979). [ nnt> 1 Marina Beach was previously assigned a catalog number because of Snowy Plover nesting. We have not L UU3| included information on this species in this report. See Page & Stenzel (1979). 214 AREA 454, Monterey (cont'd.) 215 AREA 454, Monterey (cont'd.) 006) Bird Rock 36°35'31"N, 121°57'59"W Bird Rock offers excellent viewing opportunities for seabirds, sea lions and harbor seals. See appendix B. Brandt's Cormorant 1,340 Black Oystercatcher 2 Western Gull 1_0 Total 1,352 Brandt's Cortrwrant 2,000 Brandt's Cornjorant 600 (Nelson & Sowls, 6/23/80, A, II) (Nelson & Sowls, 6/10/79, M, II ) (Nelson & Sowls, 6/10/79, M, III) (Nelson & Sowls, 7/ 6/ 79, A, III) (Reynolds, 7/15/70,A) 42 42 42 42 36 ^ Bird Kock PhoU) by Ai t Sowls 007) Pinnacle Point Area 36°3r25"N, 121°57'14"W Brandt's Cormorant 200 Pelagic Cormorant 22 Black Oystercatcher P Western Gull 14 Pigeon Guillemot ^OO Total 336 Brandt's Cortnorant 125 Brandt's Cormorant 30 Pelagic Cormorant 30 Slack Oystercatcher 2 Western Gull 25 Pigeon Guilleniot 2 P = probably present (Nelson & Sowls, 6/11/79, B,7/31&8/3/79,L, III) (Nelson & Sowls, 6/11/79, B,7/31&8/3/79,L, II) (Nelson & Sowls, 6/11/79, B,7/31&8/3/79,L, II ) (Nelson & Sowls,6/ll/7/13&8/3/79,B,L,I II ) (Nelson & Sowls, 6/11/79, B,7/31&8/3/79,L, III) (Varoujean & Brl9gs,4/25&7/14/72,M) (Reynolds, 5/ 6/70 ,H) (Reynolds, 5/6/ 70 ,H) { Reynolds, 5/6/ 70 ,H) ( Reynolds, 5/6/ 70 ,M) (Reyno]ds,5/6/70,M) 42 42 42 42 42 43 36 36 36 36 36 216 AREA 454, Monterey (cont'd.) Section from U.S.G.S. 1:24,000 scale map: Monterey, Calif. Rn Cypress Point RocJt Carmtl Point ji* Pinnacle Poin\ •* S»o\ Rocks. ' ..o Section from U.S.G.S. 1:24,000 scale map: Monterey, Calif. I ■ 217 AREA 454, Monterey (cont'd.) 008) Sand Hill Cove 36«31'01"N, 121°57'0T'W Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total Pelagic Corjnorant Pelagic Connorant Pigeon Guillemot 36 (Nelson & Sowls, 8/2/79, L, I) 42 2 (Nelson & Sowls, 8/2/79, L, III) 42 2 (Nelson & Sowls, 6/24/80, L, II) 42 20 (Nelson & Sowls, 6/24/80, L, III) 42 58 ._ 36 (Briggs & Varou jean ,"4/ ?5&7/1 4/72,(7 43 26 (Nelson & Sowls, 6/24/80, 1,11) 42 12 (Briggs & Veroujean,4/25&7/14/72,L) 43 009) Bird Island 36°30'25"N, 121°56'33"W Bird Island is the second largest Brandt's Cormorant colony in California, after the Farallon Islands (429 012). It is also the most northern site for nesting Brown PeUcans ever recorded, although no nesting peUcans have been observed here since 1963 (Baldridge, 1973). If recovery of the Brown Pelican continues, this site may be recolonizied. Bird Island offers excellent viewing opportunities (see appendix B ). (Nelson & Sowls, 6/23/80, A, II) 42 (Nelson & Sowls, 8/2/79, L, III) 42 (Nelson & Sowls, 6/11/79,6, 6/12/79, L, III) 42 (Nelson & Sowls, 6/11/79, B, III) 42 (Nelson & Sowls, 6/24/80, M, III) 42 (1927-1963; see Baldridge 1973) 7 (Reynolds, 5/6/69, M) 36 (Briggs & Varoujeaii,4/25&7/14/72,M) 43 (Nelson & Sowls, 7/6/79 ,A,ni) 42 (Briggs & VarouJean,4/25&7/14/72,H) 43 (BHggs & Varoujean, 4/258.7/14/72 ,M) 43 (Briggs & Varoujean,4/2S&7/14/72.H) 43 Brandt's Cormorant 4,200 Pelagic Cormorant 16 Black Oystercatcher 4 Western Gull 46 Pigeon Guillemot 4 Total 4,270 Brown Pelican - 0-110 Brandt's Connorant 800 Brandt's Connorant 1.568 s,Brandt's Cormorant 5,000 Black Oystercatcher 2 Western Gull X Pigeon Guillemot- X X = present 218 AREA 454, Monterey (cont'd.) Section from U.S.G.S. 1:2^,000 scale map: I Bird Island Photo by Jay Nelson 219 AREA 454, Monterey (cont'd.) 010) Castle Rocks & Mainland 36°22'35"N, 121°54'25"W Brandt's Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Common Murre Pigeon Guillemot Total Brandt's Cormorant Brandt's Comorant Pelagic Cormorant Black Oystercatcher Black Oystercatcher Western Gull Western Gull Cdtimon Murre Pigeon Guillenwt 18 96 6 78 3,500 88 3,780 534 300 62 6 2 50 20 200 2 (Lester, (Lester, (Lester, (Lester, (Lester, Nelson Nelson Nelson Nelson Nelson & Sowls, 6/12/80,8 Sowls, 6/1 2/80, B Sowls, 6/12/80,8 Sowls, 6/12/80,8 Sowls, 6/12/80,8 I) I) I) (Nelson & Sowls, 7/14/79, M,6/20&8/l/79,B, III) (Nelson & Sowl s, -7/1 4/79, M, 6/ 20&8/1 /79,8a H (Reynolds. 5/6/70,M} (Nelson & Sow! s,6/20&8/V79, 8,11) (Helson & Sowls, 6/20/79, 8,11) ( Reynolds, 5/ 6/ 70, M) (Nelson S Sowls,6/20&8/1/79,B,II) (Reynolds, 5/ 6/70, M) (Reynolds, 5/6/70, M) @ Hurricane Point Rocks 36^21 '40"N, 12r54'25"W Brandt's Cormorant 444 Pelagic Cormorant 50 Black Oystercatcher 10 Western Gull 72 Common Murre 2,300 Pigeon Guillemot 80 Tufted Puffin 2 Total 2,958 Brandt's Cormorant 582 Pelagic Cormorant 10 Western, Gull 50 Common Murre 400 Pigeon Guillemot 4 (Lester, (Lester, (Lester, (Lester, (Lester, (Lester, (Lester, Nelson Nelson Nelson Nelson Nelson Nelson Nelson Sowls, 6/12/80,8 Sowls, 6/12/80,8 Sowls, 6/12/80,8 Sowls, 6/12/80,8 Sowls, 6/12/80,8 Sowls, 6/12/80,8 Sowls, 6/12/80,8 (Nelson & Sowls, 7/14/79,H,8/l/?9,B, 11!) (Nelson & Sowls, 7/14/79,M.8/l/79,B, II) (Nelson & Sowls,7/14/79,H, 8/1/79, 8,111) (Reynolds, 5/6/ 70, H) (Nelson & Sowls, 7/14/79.M,8/l/7$,B, III) I) ) I) I) I) I) ) 012) Point Sur 36°18'22"N, 121°53'39"W Pelagic Cormorant 54 Black Oystercatcher 2 Western Gull 6 Pigeon Guillemot 4 Total 66 (Lester, Nelson & Sowls, 6/12/80, B, II) (Lester, Nelson & Sowls, 6/12/80, 8, III) (Lester, Nelson & Sowls, 6/12/80,8, III) (Nelson & Sowls, 8/1/79, 8, III) 220 AREA 454, Monterey (cont'd.) 36°22»30'' -)- 121°55' Castle Rock { *e Castio Rock Bixby Landi €>-: Hurricane Point Section from U.S.G.S. 1:24,000 scale map: 012 Point S 221 AREA 454, Monterey (cont'd.) 013) "Torre Canyon Rocks" 36°n'25"N, 121°42'46"W Brandt's Cormorant Pelagic Cormorant Black Oystercatcher Total Brandt's Cormorant 0 22 _i 24 125 (Nelson & Sowls, 6/22/79,8,1) (Nelson & Sowls, 6/22/79, B, II) (Nelson & Sowls, 6/22/79, B, III) (Reynolds, 6/ 14/70,M) 42 42 42 36 014] "Partington Ridge North" 36°10'06"N, 121°41'14"W Double-crested Cormorant Brandt's Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total Doubl e -ores ted 'tbrmoratt^"*" Brandt ' s Cormorant 6 910 26 4 30 80 1,050 0-10 125 (Baldridge,1980,M) e (Nelson & Sowl s, 6/23/79, B, 7/13/79, M, III) 42 (Nelson & Sowls, 6/23/79, B, II) 42 (Nelson & Sowls, 6/23/79, B, III) 42 (Nelson & Sowls, 6/23/79, B, III) 42 (Nelson & Sowls, 6/23/79, B, III) 42 ( Reynolds, 5/ 14/ 70, M) 36 @ McWay Rocks Brandt's Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total ;0randt*s Cortfwrant 36' °09'46"N, > 20 2 8 100 (Nelson (Nelson (Nelson (Nelson & & & & 121°40*44"W Sowls, 6/23/79, B, I) Sowls, 6/23/79,8, III) Sowls, 6/23/79, 8, III) Sowls, 6/23/79, 8, III) 130 80 (Reynolds, 7/22/ 70, M) 42 42 42 42 36 111 AREA 454. Monterey (cont'd.) 223 AREA 454, Monterey (cont'd.) 016) "Anderson Canyon Rock" 36°06*58"N, 121°36'58"W Brandt's Cormorant Pelagic Cormorant Total Brandt's Cormorant 0 (Nelson & Sowls, 6/23/79,8, I) 82 (Nelson & Sowls, 6/23/79, 8, II) 82 284 (Reynolds, 7/22/70,H) 42 42 36 017) "Burns Creek Rocks" 36°08'29"N, 12r39'28"W Cormorant (Unid.) 2 Brandt's Cormorant 348 Western Gull 4 Pigeon Guillemot 24 Total 378 Brandt's Cormorant 60 42 (Nelson & Sowls, 6/23/79, B, 7/13/79, M) 42 (Nelson & Sowls, 6/23/79,8, 7/13/79, M, III) 42 (Nelson & Sowls, 7/13/79, M, III) 42 (Nelson & Sowls, 7/13/79, M, III) 42 (ReynQlds»7/22/70,M) 36 018) Dolan Rock 36°05'06"N, 121°37'02"W Brandt's Cormorant 8fandt*s Cormora 0 (Nelson & Sowls, 7/23/79^6,8/2/79, A, I) 42 ~ (Rey«olds,7/TS/70,A} tm^^ 36 019) Square Black Rock 36°04'21"N, 121°36'35"W Brandt's Cormorant Brandt's Cormorant Brandt's Cormorant 0 (Nelson & Sowls, 6/23/80, A, I) 42 0 (Nelson & Sowls, 7/23/79,8, 8/2/79, A, I) 42 20-40 (Reynolds, 7/15/70, A) 36 224 AREA 454, Monterey (cont'd.) S ' Doldn , / / Stung 1 @ Dolan Rock \ \ | 36O05' '\\ 12X°35' ^1 BM 223 — \ ' 11*9 ' «k^ S ) 26 '^'7- *( 1 Block '^ / i' \ , ; Square Black * .\ . ^**" • ' '' T" ' >Roc^ * V ^ Section from U.S.G.S. 1:24,000 scale map: Lopez Pt., Calif. mi9) • \!r^ \^^ ^^ Kb \ _ 0 4 1 225 AREA 454, Monterey (cont'd.) 020) Lopez Rock 36°0r34"N, 121°34'46"W Brandt's Cgrm^ f ra ndJt ' s IS rmo r a n t Brandt's Cormorant 0 (Nelson & Sowls,6/23/80,A,I) 0 TNetsonl. S6wTs;77237H3,S7f77f;S;^ 100 (Reynolds, 7/23/70, M) 42 42 36 rnoiA Davenport 37^00 '30"N, 122°11'30"W to ^ ' Pt. Santa Cruz 37°57'10"N, 122°0ri5" No map is provided for this site as it extends along a lengthy stretch of coastline. See page 213 Pelagic Cormorant 28 Black Oystercatcher P Western Gull 2 Pigeon Guillemot 1 ,200 Total 1,230 P = probably present (Nelson & Sowls, 7/15/79, B, I) (Nelson & Sowls, 7/15/79, B, I) (Nelson & Sowls, 7/15/79, B, II) (Nelson & Sowls, 7/15/79, B, III) 42 42 42 42 022) Pescadero Rock 36°33'43"N, 121°56'33"W Black Oystercatcher Western Gull Total 2 20 22 (Nelson & Sowls, 6/11/79, BL, III) (Nelson & Sowls, 6/11/79,61, I) 42 42 023) "Guillemot Island Area" 36"31 '25"N, 12r56'47"W (Nelson & Sowls, 6/11/79, BL, 8/3/79, M, II) 42 (Nelson & Sowls, 6/11/79, BL, II) 42 (Nelson & Sowls, 6/11/79, BL, 8/3/79, M, II) 42 (Nelson & Sowls, 6/11/79, BL, 8/3/79, M, III) 42 Pelagic Cormorant 14 Black Oystercatcher 4 Western Gull 60 Pigeon Guillemot 40 Total 118 226 AREA 454, Monterey (cont'd.) Section from U.S.G.S. 1:24,000 scale map: Lopez Pt. , Calif. Km 020 Lopez Rock Lopez Point A o Section from U.S.G.S. 1:24,000 scale map: Monterey, Calif. insef Po/nf Peicodero Poinf Carm»l Point PinoocI* Poin\ Pinnacle t _^ South Poinrt Section from U.S.G.S. 1:24,000 scale map: Monterey, Calif. Km I I I 227 AREA 454, Monterey (cont'd.) Western Gull Pigeon Guillemot Total X = present. 024) Yankee Point 36°29'29"N, 12r56'41"W 8 (Nelson & Sowls, 6/11/79,8, II) X (Nelson & Sowls, 6/11/79,8, III) 8 42 42 [025) Lobos Rocks 36°27'18"N, 121°56'10"W Western Gull 12 (Nelson & Sowls, 6/11/79,8, II) 42 Lx)bos Rocks Photo by Art Sowls 026) "Soberanes Creek Rocks" 36°27'18"N, 12P55'35"W (Nelson & Sowls, 6/11/79, 8, I) (Nelson & Sowls, 7/17/79, M, II) (Nelson & Sowls, 6/11/79, 8, III) Pelagic Cormorant 30 Western Gull 4 Pigeon Guillemot 40 Total 74 42 42 42 228 AREA 454, Monterey (cont'd.) 229 AREA 454, Monterey (cont'd.) 027) "Soberanes Point South" 36°26'47"N, 121°55'35"W Pelagic Cormorant 2 (Nelson & Sowls, 6/11/79,6,1) 42 Black Oystercatcher 4 (Nelson & Sowls, 6/11/79,6, III) 42 Western Gull _6 (Nelson & Sowls, 6/11/79, 6, III) 42 Total 12 028) Rocky Point 36°24'06"N, 121°54'40"W Pelagic Cormorant 6 (Nelson & Sowls, 6/11/79, 6, I) 42 Black Oystercatcher 4 (Nelson & Sowls, 6/11/79, 6, III) 42 Western Gull 20 (Nelson & Sowls, 6/11/79,8, III) 42 Pigeon Guillemot 40 (Nelson & Sowls, 6/11/79,6, III) 42 Total 70 029) "Bench Mark-227x" 36°23'21"N, 12r54'13"W Pelagic Cormorant 68 (Nelson & Sowls, 6/11/79, 6, 6/12/79, BM, II) 42 Black Oystercatcher 2 (Nelson & Sowls, 6/11/79,6, 6/12/79, BM, III) 42 Western Gull 300 (Nelson & Sowls, 6/11/79, 6, 6/12/79, BM, III) 42 Pigeon Guillemot 160 (Nelson & Sowls, 6/11/79, 6, 6/12/79, BM, III) 42 Tatal 530 230 AREA 454, Monterey (cont'd.) Section from U.S.G.S. 1:2A*000 scale map: Soberanes Pt . , Calif. Km Rocky Point 028) 231 AREA 454, Monterey (cont'd.) Pelagic Cormorant Western Gull Pigeon Guillemot Total P = probably present 030) "Molera Rock" 36°16'45"N, 121°51'30"W 26 (Nelson & Sowls, 6/22/79, BM, I) 8 (Nelson & Sowls, 6/22/79, BM, II) _P (Nelson & Sowls, 6/22/79, BM, II) 34 42 42 42 031) Cooper Point and Islands 36°14'55"N, 121°50'10"W Brandt's Cormorant Pelagic Cormorant Pigeon Guillemot Total No nesting biri% 72 (Nelson & Sowls, 6/22/79,6, II) 20 (Nelson & Sowls, 6/22/79, B, II) 40 (Nelson & Sowls, 6/22/79,8, III) 132 (Reynolds, 7/15/70,A) 42 42 42 36 032) Pfeiffer Point 36°35'18"N, 121°47'35"W Cormorant (Unid.) Brandt's Cormorant Pelagic Cormorant Pigeon Guillemot Total 2 6 4 _8 20 (Nelson & Sowls, 6/22/79, B, II) (Nelson & Sowls, 6/22/79,8, I) (Nelson & Sowls, 6/22/79, 8, I) (Nelson & Sowls, 6/22/79,8, III) 42 42 42 42 (033^ Grimes Point Brandt's Cormorant 16 Pelagic Cormorant 20 Black Oystercatcher 2 Pigeon Guillemot 40 Total 78 36°12'20"N, 121°44'15"W (Nelson & Sowls, 6/22/79, 8, II) (Nelson & Sowls, 6/22/79, 8. II) (Nelson & Sowls, 6/22/79, B, III) (Nelson & Sowls, 6/22/79, 8, III) 42 42 42 42 034) Lafler Rock and Mainland 36°12'N, 121°43'36"W Brandt's Cormorant Pelagic Cormorant Pigeon Guillemot Total 12 (Nelson & Sowls, 6/22/79, 8, I) 6 (Nelson & Sowls, 6/22/79, 8,1) 20 (Nelson & Sowls, 6/22/79,8, III) 38 42 42 42 232 AREA 454, Monterey (cont'd.) Section from U.S.G.S, 1:24,000 scale map: Big Sur, Calif. Cooper 1=ointt§*—>/s, ' O \ o* . \ /' Nf * ' \^ * & f03lj V- 27 L.-,J \ ■ - ■ ' \ '^ > ■- ' ' ' '^ . ' "v LOS • V \ < * M Pfeiffer Point V . r-. ^ 3aa — ' { N A T I"' "' v>"-. 3 ^'F 0 R E S Section from U.S.G.S. 1 : 24, 000 scale map: Pfeiffer Pt. , Calif. \ Pfeiffer Rock r %*• V*.. • .' % ♦ Kb (032) 0 \ 1 ( 36°12'30" 12I°45' Section from U.S.G.S. 1:24,000 scale map: Partington Ridge, Calif. h Ka •\ 233 AREA 454, Monterey (cont'd.) 035) "Partington Ridge South" 36°00'N, 121°40'40"W Pelagic Cormorant Western Gull Pigeon Guillemot Total 20 30 416 466 (Nelson & Sowls, 6/23/79,6,1) 42 (Nelson & Sowls, 6/23&7/13/79,B, III) 42 (Nelson & Sowls, 6/23&7/13/79,B, III) 42 [036] "Bench Mark 247" 36°02'N, 121'^34'45"W Pelagic Cormorant 6 (Nelson & Sowls, 6/23/79,8, I) 42 037) "Rockland Landing North" 36°00'57"N, 121°32'30"W Brandt's Cormorant Pelagic Cormorant Total 1*e1agic Cormorant 16 (Nelson & Sowls, 6/23/79, B, II) 64 (Nelson & Sowls, 6/23/79,8, II) 80 42 42 36 234 AREA 454, Monterey (cont'd.) Section from U.S.G. 1:24,000 scale map: Partington Ridge, Calif. Km Section from U.S.G.S. 1:24,000 scale map: Loper Pt. , Calif. Ka 36°02'30*"^ <^/ \ < too einos 100 - 1,000 Bmos 1.000 - 10.000 BtROS 10.000 . 100,000 BtRDS OV£n 100.000 BIROS B-i- 237 AREA 477, San Luis Obispo (cont'd.) sample Colony No. - Colony name 004 'Gull Rock^ Pelagic Cormorants / Pelftgfc Coffiioirants Lat. -Long. 39°35;20"N,12r35'45 'Number breeding birds ■ Investigators ■ Survey date "1? r • Data qual. - see text 40 (Nelson & Sowls ,6/14/79,8,11 ) 42 48 {0sbor"ne,6/5/69) /* 35 A = aerial Reference l_ Clear lines give the most recent or the best estimates available. Stipple lines give additional estimates for other years. Survey type -I B = boat M = from mainland L = on site ® Small rocks and mainland 35°55'16"N,121°28'22"W north and east of Plaskett Rock Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total 42 6 64 30 142 (Nelson & Sowls, 6/25/79, B, I) -^2 (Nelson & Sowls, 6/25/79,8, II ) 42 (Nelson & Sowls, 6/25/79,8, 7/13/79, M, III) 42 (Nelson & Sowls, 6/25/79,8, III) 42 36 002) Plaskett Rock 35°55' 14"N,12T'28'41 "W (Nelson & Sowls, 6/23/80, A (Nelson & Sowls, 6/25/79, B (Nelson & Sowls, 6/25/79, B (Nelson & Sowls, 6/25/79, 8 (Nelson & Sowls, 6/25/79, 8 Brandt's Cormorant 0 Pelagic Cormorant 10 Black Oystercatcher 2 Western Gull 60 Pigeon Guillemot 20 Total 92 Sirarrdt^s Cormorant im Brandt's Cormorant 0 Piqeon Guillemot 2 (Reynolds. 5/4/70 ,«) (Nelson & Sowls, 6/ 2 J (Reynolds, 5/4/70. M) ,11) ■12 ,11) 42 ,111) 42 ,111) 42 ,111) 42 36 .8/2/79,A»I) 42 36 238 AREA 477, San Luis Obispo (cont d.) Plaskett Rock Photo by Jay Nelson 239 AREA 477, San Luis Obispo (cont'd.) 003) Cape San Martin 35°53'17"NJ21°27'55"W Brandt's Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total "^Brandt's Conrrorant Brandt's Cormorant Western Gull Pigeon Guillemot 680 26 4 474 8 1,192 400 U228 140 2 (Nelson & Sowls, 6/23/80, A, II) (Nelson & Sowls, 6/24/79, M, 6/25/79, B, II) (Nelson & Sowls, 6/24/79, M, 6/25/79, B, III) (Nelson & Sowls, 6/24/79, M, 6/25/79, B, III) (Nelson & Sowls, 6/24/79, M, 6/25/79,6, III) 42 42 42 42 42 (Reynolds, 5/4/ 70, M) 36 (Nelson & Sowls, 6/24/79,M, 6/25/79,8, 8/2/79,A, II) -^2 {Reynolds, 5/4/70, M) 36 (Reyn9Tds,S/4/70,M) 36 004) Unnamed Rock 35°53'05"N,121°27"46"W Pelagic Cormorant Black Oystercatcher Western Gull Total SrarKlt's Connorant 2 2 12 16 150 (Nelson & Sowls, 6/24/79, M, 6/25/79,8, II) 42 (Nelson & Sowls, 6/24/79, M, 6/25/79, B, III) 42 (Nelson & Sowls, 6/24/79,M, 6/25/79,6,111} 42 (Reynolds, 5/4/70,M) ' ' 36 240 AREA 477, San Luis Obispo (cont'd.) "•In ♦ sand Kelp 003 Kelp . . .Uncovers *^* 3 feet cock, f rocky '5 '■■■■■.. '■■-/^•'*^':>"- v^ I ^ rocky^ ) Cape S an Martin Kelp ( sand , ' Section from U.S.G.S. 1:24,000 scale map: Cape San Martin, Calif. Km 004 Cape San Martin Photo by Jay Nelson 241 AREA 477, San Luis Obispo (cont'd.) (005 'Redwood Gulch Rock" 35°49' 32"NJ21°23'29"W Brandt's Cormorant Pigeon Guillemot Total Brandt's Cormorant 478 (Nelson & Sowls, 6/24/79, M, 6/25/79,3, II V 42 2 (Nelson & Sowls,6/24/79,M, 6/25/79,8, III) 42 480 600 (Reynolds. 7/21/70,M) 36 Cormorant (unid.) Black Oystercatcher Western Gull Total Cormorant (unid.) Black Oystercatcher Black Oystercatcher Western Gull 006) La Cruz Rock 35°42'23"N,121°18'45"W 0 (DeGange & Nelson, 7/15/80, L, I) 2 (DeGange & Nelson, 7/15/80,1,1) 10 (DeGange & Nelson, 7/15/80, L, II) 12 4 (Nelson ^ Sowls,6/25/79,BL,I) 2 (Reynolds, 7/1 9/70, M) 2 (Nelson & Sowls,6/25/79»BL,I) 20 (Nelson & Sowls, 6/25/79,81, III) 42. 42 42 42 36 42 42 @ Piedras Blancas 35°39'52"N,121°17' 18"W Nelson & Sowls, 6/23/80, A, II) Sorensen, 1980, M, III) Nelson & Sowls, 6/26/79,8, III) Nelson & Sowls, 6/26/79,6, III) Jameson, 1980, M) Reynolds, 7/15-19/70, AM) Nelson & Sowls, 8/2/79, A, II) Reynolds, 7/15-19/70, AM) Reynolds, 7/15-19/70, AM) Reynolds, 7/15-19/70, AM) Nelson & Sowls, 6/26/79,8, III) Brandt's Cormorant 1,200 ( Black Oystercatcher 2 ( Western Gull 56 ( Pigeon Guillemot 50 ( Tufted Puffin 0 ( Total 1,308 Brandt's Cormorant 200 ( Brandt's Cormorant 1 ,360 ( Western Gull 8 ( Pigeon Guillemot 2 ( Tufted Puffin 2 ( Tufted Puffin 2 ( <2 30 42 42 30 36 42 36 36 36 42 (008) ^°''° ^*y was previously assigned a catalog number because of Snowy Plover nesting. We have not ^ ' included information on this species in this report. See Page & Stenzel (1979). lor information on Morro Rock see 026. 009) Point Buchon 35°15'20"N,121°53' 58"W Pelagic Cormorant Black Oystercatcher Pigeon Guillemot Total Pelagic Gonnorant 4 6 20 30 46 (Chambers, Rodstrom & Sowls, 7/6/79, B, II) 42 (Chambers, Rodstrom & Sowls, 7/6/79, 8, III) 42 (Chambers, Rodstrom & Sowls, 7/6/79,8, III) 42 ( Frame »1972,«) 19 242 AREA 477, San Luis Obispo (cont'd.) 35050' 121°25' (oosV'" Section from U.S.G.S. 1:24,000 scale map: Villa Creek, Calif. Km 121°20' f 35°42'30" woe) — I La Cruz Rock Section from U.S.G.S. 1:24,000 scale map: Plerdas Blancas, Calif, Km I < I 121°17'3Q" " 35^40 I COAST duARD fl^SS^ Point Piedras Blancasf ♦* ^'^ Section from U.S.G.S. 1:24,000 scale map: Plerdas Blancas, Calif. Km 1 I •Point ^Dchcjn** [009 \>- vf-^ 35°15' Section from U.S.G.S. 1:24,000 scale map: Morro Bay, Calif. Km ' I i< 1 ^-\ \ I 243 AREA 477, San Luis Obispo (cont'd.) 010) Unnamed Rocks 35°14'40"N,120°53'39"W Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total Pelagic CorfBorant Pelagic Corfnorant Black Oystercatcher Western Gull 64 (Lester, Nelson & Sowls, 6/10/80, B, II) 42 10 (Chambers, Rodstrom & Sowls, 7/6/79, B, III) 42 22 (Lester, Nelson & Sowls, 6/10/80, B, III) 42 200 (Chambers, Rodstrom & Sowls, 7/16/79,8, III) 42 296 50 (frame, 1972,H) 19 62 (Gharnbers, Rodstrom & Sow! sj/ 6/79, B,ir) 42 4 (Lester, Nelson & Sowls, 6/10/80,8,11 I) 42 54 (Chambers, Rodstrom & Sgw1's,7/6/79, 8, in) 42 on) Lion Rock 35°31 '01"N,120°52'15"W While Lion Rock is not an important nesting island, it is a critical roost rock. In the fall, up to 5,000 cormorants, hundreds of Brown Pelicans, and lesser numbers of Western and Heermann's Gulls roost here. California Sea lions haul out here in large numbers. Brandt's Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total iBrandt's Cormorant ;8randt's Cormorant ^Brandt's Cormorant ; Brandt's Cori!«)rant :; Pelagic Cormorant : Black Oystercatcher i Western Sull 0 0 2 34 30 66 700 (Nelson & Sowls, 6/23/80, A, I) (Lester, Nelson & Sowls, 6/10/80, 8, II) (Lester, Nelson & Sowls, 6/10/80, 8, II) (Lester, Nelson & Sowls, 6/10/80, 8, III) (Chambers, Rodstrom & Sowls, 7/6/79, BL, III) . (Reynolds, 7/15/70,A) 2004- Frame, 1972, L) 100 (Chambers,! 978, BL) (Chanibers, Rodstrofn & (Fraine, 1972,1) (Chanibers, Rodstrom S 0 30 4 20 Sowl 5,7/6/79, 8, L, 8/2/79, A, I) Sowls ,7/6/ 79, 8L, III) (ChaiBbers , Rodstrom & Sowl s , 7/6/79 ,8L ,111) 012) Unnamed Rock 35°12'06"N,120°50'28"W I This site was reported by Reynolds in 1970. Exact location of this site is uncertain. Data has been combined with number 030. 244 AREA 477, San Luis Obispo (cont'd.) Section from U.S.G.S. 1:24,000 scale map: Port San Luis, Calif. 245 AREA 477, San Luis Obispo (cont'd.) (013) "36 North" 35°58'36"N,121°29'15"W Pelagic Cormorant' 6 (Nelson & Sowls, 6/25/79,8, I) 42 014) "Larus Rock" 35°57'44"N,121°29'-01"W Pelagic Cormorant 2 (Nelson & Sowls, 6/24/79, M, 6/25/79,6, I) 42 Black Oystercatcher 2 (Nelson & Sowls, 6/24/79, M, 6/25/79,8, I) 42 Western Gull 20 (Nelson & Sowls, 6/24/79, M, 6/25/79,8, II) 42 Total 24 015) Unnamed Point 35°57'00"N,121°28'51"W Pelagic Cormorant 6 (Nelson & Sowls, 6/25/79, 8, I) 42 81ack Oystercatcher 2 (Nelson & Sowls, 6/25/79, 8, III) 42 Western Gull _4 (Nelson & Sowls, 6/25/79, 8,111) 42 Total 12 016) Mainland point across from Bird Rock 35°52'37"N,121°26'59"W Pelagic Cormorant 38 (Nelson & Sowls, 6/25/79, 8, I) 42 Black Oystercatcher _2 (Nelson & Sowls, 6/25/79,8, III) 42 Total 40 [017) Point north of Redwood Gulch 35°50'20"N,121°24'04"W Pelagic Cormorant 26 (Nelson & Sowls, 6/25/79, 8, I) 42 246 AREA 477, San Luis Obispo (cont'd.) TnrT"!^ U; y.-^^A-iv Section from U.S.G.S. 1:24,000 scale map: Villa Creek, Calif. Km h 247 AREA 477, San Luis Obispo (cont'd.) 018) Seastack south of Redwood Gulch 35°49'30"N,121°23'22"W Pelagic Cormorant Black Oystercatcher Western Gull Total P = probably present 16 (Nelson & Sowls, 6/25/79, B, I) P (Nelson & Sowls, 6/25/79, B) _6 (Nelson & Sowls, 6/25/79,8, I) 22 42 42 42 019) "Unmapped Island" 35°48'20"N,121°22'26"W Pelagic Cormorant Pigeon Guillemot Total 56 (Nelson & Sowls, 6/25/79, 8, II) 12 (Nelson & Sowls, 6/25/79, 8,111) 68 42 42 [020j "Salmon Creek" 35°48'31"N,121°21 '47"W Pelagic Cormorant 12 (Nelson & Sowls, 6/25/79, 8, I) 42 021) Arched peninsula South of Salmon Creek 35°48'05"N,121°2ri4"W Pelagic Cormorant Pigeon Guillemot Total 8 (Nelson & Sowls, 6/25/79, 8, I) 80 (Nelson & Sowls, 6/25/79, B, III) 88 42 42 248 AREA 477, San Luis Obispo (cont'd.) 35050' 121°25' Section from U.S.G.S. 1:24,000 scale map: Villa Creek, Calif. Km Uncovers Section from U.S.G.S. 1:24,000 scale map: Burro Mountlan, Calif. 249 AREA 477, San Luis Obispo (cont'd.) 022) "Ragged Point Lodge Colony" 35°46'53"N,121°19'56"W Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total 46 2 14 20 82 (Nelson & Sowls, 6/24/79, M, 6/25/79,6,1) 42 (Nelson & Sowls, 6/24/79, M, 6/25/79, B, III) 42 (Nelson & Sowls,6/24/79,M,6/25/79,B,II ) 42 (Nelson & Sowls, 6/24/79, M, 6/25/79, B, III) 42 023) "3 Rocks" 35°45'06"N,121°19'07"W Pelagic Cormorant Western Gull Total 38 _2 40 (Nelson & Sowls,6/25/79,B,I ) (Nelson & Sowls, 6/25/79, B, II) 42 42 024) Two rocks south of Point Piedras Blancas 35°39' 30"N,121°16'02"W Western Gull Pigeon Guillemot Total 48 (Nelson & Sowls, 6/26/79, B, II) 20 (Nelson & Sowls, 6/26/79, B, III) 68 42 42 (025) Island south of Cayucos Point 35°26'45"N,120°55'51"W Black Oystercatcher 2 (Nelson & Sowls, 6/26/79, BL, I) 42 250 AREA 477, San Luis Obispo (contd.) Section from U.S.G.S. 1:24,000 scale map: Burro Mountlan, Calif. Kb ■ KelD • KelP: Uncovers 3 teet.^: H.k, . Irocky ■ tocky rocky Section from U.S.G.S. 1:24,000 scale map: Burro Mountlan, Calif. Km > * N ( » BM 98^^^^^ Section from U 1:24,000 scale S aG • S • map: "1 COAST dUARD ?E^-- ]i,^is^ ^*^ ' ><^'*^'\. ' !: (~^' Lighthouse V * *** ••'.••V Point Piedras Blancas ««'''V^^^v^ ^/t « + 4"' <-^:^i Piedras Blancas, Km Calif. u 0 ^ 1 (00^ ^Oe^^ X- 0-l!fl » • * t ♦ Section from U.S.G.S. 1:24,000 scale map: Cayucos, Calif. Km 251 AREA 477. San Luis Obispo (cont'd.) 026) Morro Rock and Pillar Rock 35°22'13"N,120°52'08"W Nelson, 7/7/79,8,11) Nelson, 7/7/79, B, II) Nelson, 7/7/79, B, III) Nelson, 7/7/79, B, III) Pelagic Cormorant 40 (Lester & Black Oystercatcher 2 (Lester & Western Gull 120 (Lester & Pigeon Guillemot 40 (Lester & Total 202 42 42 42 42 Mono Rock Photo by Jay Nelson 027) Spooner's Cove 35°16'21"N,120°53'57"W Western Gull Pigeon Guillemot Total 2 (Nelson, 6/11/80, M, I) 100 (Nelson, 6/11/80, M, III) 102 42 42 252 AREA 477, San Luis Obispo (cont'd.) Section from U.S.G.S. 1:24,000 scale map: Morro Bay South, Calif. Section from U.S.G.S. 1:24,000 scale map: Morro Bay South, Calif. Kn I ' 253 AREA 477. San Luis Obisp^ ;;;ont'd.) ^28) "Pup Rock and Adjacent Mainland" 35°13'00N,120°52'n"W Black Oystercatcher Western Gull Total iMestern Gull 2 (Lester, Nelson, & Sowls, 6/10/80,8, III) 42 54 (Lester, Nelson & Sowls,6/10/80,L,II ) 42 56 40 (Chambers, Rodstrora & Sowls, 7/6/79, BL»II) ^2 029) Diablo Rock and Adjacent Mainland 35°12'36"N, 120°51'38"W Brandt's Cormorant 212 (Lester, Pelagic Cormorant 16 (Lester, Western Gull 4 (Lester, Pigeon Guillemot 60 (Lester, Total 292 Brandt's Cormorant " 360 (Nelson & Pelagic Corn^rant 22 (Chambers Black Oystercatcher 2 (Chambers Western Gull 4 {Chambers Pigeon Guillemot 30 i::::::y:o:y:::::::-:;:-:>:;:s;>::::>:->::>:- (Chambers Nelson & Sowls, 6/10/80,8, II ) Nelson & Sowls, 6/10/80, B, II) Nelson & Sowls, 6/10, 80, B, II ) Nelson, & Sowls, 6/10/80, B,I I ) ^<'*A^'W^«. sow!s,g/27fOT!fT" , Rodstrom & Sowls, 7/6/793,11) , Rodstrom & Sowls, 7/6/79, B, 11 H , Rodstrom & Sowls,7/6/79,e,I! I- , Rodstrom & Sowls,7/6/?9^B,Ill; 4? 42 42 42 42 42 42 42 42 030) Diablo Canyon Nuclear Power Plant South 35°12'07"N, 120°50'39"W Lester, Nelson & Sowls, 6/10/80, B, III) 42 Lester, Nelson & Sowls, 6/10/80,8, II ) 42 Chambers, Rodstrom & Sowls, 7/6/79,8, III) 42 Lester, Nelson & Sowls, 6/10/80, 8, II) 42 Chambers, Rodstrom & Sowls, 7/6/79,8, III) 42 Chambers, Rodstrom S %m\sJfWW0^) ^'^ Reynolds, 7/15/70, A) 36 Chambers, Rodstrom & Sowls, 7/6/79, B, I) 42 Chambers, Rodstrom & Sowls, 7/6/79,8, II) 42 Chambers, Rodstrom & Sowls, 7/6/79,6, 1 II) 42 Brandt's Cormorant 100 ( Pelagic Cormorant 82 ( Black Oystercatcher 4 ( Western Gull 10 ( Pigeon Guillemot 132 ( Total 328 Cormorant (unid.) 16 ( Brandt's Cormorant 200 ( Brandt's Cormorant 16 ( Pelagic Cormorant 18 ( Western Gull 4 ( 254 AREA 477, San Luis Obispo (cont'd.) Section from U.S.G.S. : 24, 000 scale map: Port San Luis, Calif, Diablo Rock off of Diablo Canyon Nuclear Power Plant Photo by 255 AREA 477, San Luis Obispo (cont'd.) @ [031) "Double Rock Region" 35°ir39"N,120°50'29"W Pelagic Cormorant 16 (Nelson, Sowls & Watson, 6/28/79,8, II) 42 (032) Pecho Rock 35°10'45"N,120°49'00"W Brandt's Cormorant Western Gull Total Brandt's Cormorant Brandt's Cormorant 148 (Nelson & Sowls, 6/23/80, A, II) 42 4 (Lester, Nelson & Sowls, 6/10/80,8, II) 42 152 none (ReynoMs,7/15/f70,A) 36 140 (Nelson & Sowls, 8/2/79,A, II) 42 033) Smith and Whaler Islands 35°09'00"N,120°45'15"W (Nelson, Sowls & Watson, 6/28/79, BL, III) 42 (Nelson, Sowls & Watson, 6/28/79, BL, I) 42 (Nelson, Sowls & Watson, 6/28/79, BL, III) 42 Black Oystercatcher 4 Western Gull 2 Pigeon Guillemot 20 Total 26 (034) Fossil Point 35°10'26"N, 120°43'26"W Pelagic Cormorant 44 Black Oystercatcher 6 Western Gull 6 Pigeon Guillemot 110 Total 166 (Rodstrom & Sowls, 7/7/79, B, I) (Rodstrom & Sowls, 7/7/79, B, III ) (Rodstrom & Sowls, 7/7/79,8,11) (Rodstrom & Sowls, 7/7/79, B, III) 256 42 42 42 42 AREA 477, San Luis Obispo (cont'd.) Section from U.S.G.S. 1:24,000 scale map: Port San Luis, Calif. Km I I I Section from U.S.G.S, 1:24,000 scale map: Port San Lula, Calif. Kb Santa Rosa Section from U.S.G.S. 1:24,000 scale map: Flame Beach, Calif.. Km 0 ^ 1 Lone Rock ''t * # Avila ' Rock 257 AREA 477, San Luis Obispo (cont'd.) Pelagic Cormorant Black Oystercatcher Western Gull Heermann's Gull Pigeon Guillemot . Total Slack Oystercatcher 035) "Shell Beach Rocks" 35°09'06"N, 120°40'11"W 4 (Rodstrom & Sowls, 7/7/79, 8,1) 6 (Sowls, 6/11/80, M, II) U/-,(DeGange, 5/26/80, M, II) X'^CDeGange, 5/26/80, M, II) 100 (Sowls, 6/11/80, M, III) 124 6 (Rodstrom & Smls^J/Jm^ndlU ^Before 1980, Heermann's Gulls were known to breed only in the Gulf of California and along the west coast of Baja California, Mexico. Two pairs attempted to nest at Shell Beach in 1980. These represent 2 of 3 known nesting attempts by Heermann's Gulls in the state of California in 1980; the other being at Alcatraz in San Francisco Bay (Binford 1980). All 3 nesting attempts were unsuccessful. See Appendix B. X = present 42 42 42 42 42 42 036) "North Pismo Beach Rocks" 35°08'57"N, 120°39'23"W Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total 18 4 8 60 90 (Rodstrom & Sowls, 7/7/79,6,11) (Rodstrom & Sowls, 7/7/79,8, III) (Rodstrom & Sowls, 7/7/79, 8, II) (Nelson & Sowls, 5/29/79, M, III) 42 42 42 42 037) Oso Flaco Lake 35°01'42"N, 120°37'40"W Least Terns are an endangered species. Populations of Least Terns are surveyed annually. For the most cunent information contact the California Department of Fish and Game. Least Tern 12-20 (Goldwasser, 4-8/80, L) 12 (038) Point San Simeon 35°38'N, 121°12'W Pigeon Guillemot 40 (Nelson & Sowls, 6/26/79,8, III) 42 258 AREA 477, San Luis Obispo (cont'd.) Section from U.S.G.S. 1:24,000 scale map: Pismo Beach, Calif. Km t- » Lake Little Oso Flaco Lake Section from U.S.G.S, 1:24,000 scale map: Oceano, Calif. Km Section from U.S.G.S. 1:24,000 scale map: Sttft SlBftMi, Calif. Km > 259 501 Santa Maria The maps on the facing page and following page are indexes to the locations of colonies within map 501, Santa Maria. Note that all colonies on the map are not numbered consec- utively from north to south, since many previously unreported colonies have been added since initial colony numbers were assigned by Varoujean (1979). On the pages following these two maps, all colonies are listed sequentially and a detailed map of each is provided. Numbers of breeding seabirds will vary from year to year. Below are the approximate numbers of breeding seabirds within this region. Leach's Storm-Petrel X Ashy Storm-Petrel 400 Brandt's Cormorant 5,000 Double-crested Cormorant 150* Pelagic Cormorant 400 Black Oystercatcher 130 Western Gull 1,200 Pigeon Guillemot 1,400 Xantus' Murrelet 150 Cassin's Auklet 22,000 Rhinoceros Auklet 30 X = present ^ coastal population only. 260 ^\#i ^«iiii«j m%iii»< Santa Maria ^ • Oc H jy KH.OMCTCMS KIT w.oeo - Mo.ooe •mo* ovco 100.000 wno* 261 AREA 501, Santa Maria (cont'd.) sample Colony No. « Colony name 004 'Gull Rock'' 'Number breeding birds Lai. -Long. / ^Investigators -* J yC- r Stdrvey date Pelagic Cormorants /PeUgt,«;^^ Destroyer Rock 273 AREA 501, Santa Maria (cont'd.) on) Point Arguello 34°38'N, 120°38'49"W Pelagic Cormorant 30 (Lester,6/ll/80,M,II ) Western Gull 4 (Nelson & Sowls, 7/10/79, B, II) Black Oystercatcher 2 (DeGange & Nel son, 7/18/80, M, II I) Pigeon Guillemot 700 , (Lester, 6/ll/8Q,M; Nelson & Sowls, 7/10/79,8, III) Rhinoceros Auklets 30^' (Lester. 6/1 1/80, H; DeGange & Nelson, 7/18/80, M, III) Total 766 Pelagic Connoratit 20 (Nelson & Sowls, 7/ 10/ 79,8, II) Western Gull 4 (DeGange & Nelson, 7/18/80, M, III) ^ See text, page 50. 012 Rocky Point 34-33'45"N, 120 38'11"W Black Oystercatcher 2 (Nelson & Sowls, 7/10/79, B, III ) h? Pigeon Guillemot 100 (Nelson & Sowls, 7/10/79, B, III) 42 Total 102 013) Point Conception 34^26' 54"N, 120 28'13"W Pelagic Cormorant 6 (Nelson & Sowls, 7/10/79,8, III) 42 Pigeon Guillemot 30 (Nelson & Sowls,7/10/79,B,III ) 42 Total 36 274 AREA 501, Santa Maria (cont'd.) Point Conception*! Section from U.S.G.S. 1:24,000 scale map: Pt. Conccrtl*n, Calif. * Kb ' t 0 275 AREA 501, Santa Maria (cont'd.) 014) Point Bennett, San Miguel Island 34°2'N, 120°3'30"W Brandt's Cormorant 54 ( /J. ,7/20/77) 29 Pelagic Cormorant 24y^( | ,1977) 29 Black Oystercatcher p^( ' ,1977) 29 Western Gull 40 (Collins, 5/19/77) 29 Cassin's Auklet _Z0 (Collins & Newman, 1977) 29 Total 138 P = probably present ^Investigators are some or all of the following: Hunt, Pitman, Naughton, Winnett, Newman, Kelly, Briggs and Speich. Only the most significant historical data has been summarized here from intensive studies conducted in the Channel Islands, see Hunt et al. 1979 for further information. "= The estimate for entire San Miguel Island is 48 birds. 276 AntA ou I, £>ama maria (com a.) Section from U.S.G.S. 1:2A,000 scale map: San Miguel Island West Km Q^Judith Rock | 3401130" r 120O25' 277 AREA 501, Santa Maria (cont'd.) 01 5 j Harris Pt. to Cuyler Harbor 34°04'N, 120°22'W Ashy Storm-Petrel X /I ,6/25/76) Brandt's Cormorant 10 ,1976) Pelagic Cormorant ''U ,1977) Black Oystercatcher ,1977) Western Gull 28 ,1976) Pigeon Guillemot 140 ,1975-76) Xantus' Murrelet P ^ ,1975-76) Total 302 29 29 29 29 29 29 29 X = present, P = probably present ^ Investigators are some or all of the following: Hunt, Pitman, Naughton, Winnett, Newman, Kelly, Briggs and Speich. Only the most significant historical data has been summarized here from intensive studies conducted in the Channel Islands, see Hunt et al. 1979 for further information. ^ The estimate is for entire San Miguel Island is 48 birds. 278 AREA 501, Santa Maria (cont'd.) Section from U.S.G.S. 1:2A,000 scale map: San Miguel Island East 279 AREA 501, Santa Maria (cont'd.) 016) Bay Point Area 34°02'N, 120°19'W Pelagic Cormorant 52 ( (\ ,1911) 29 Black Oystercatcher P^( l ,1975-77) 2o Pigeon Guillemot 120 ( I ,1975-77) 29 172 P = probably present ^Investigators are some or all of the following: Hunt, Pitman. Naiigliton, Winnett, Newman, Kelly, Briggs and Speicli. Only the most significant historical data has been summarized here from intensive studies eonduclcd in the Channel Islands, see Hunt et al. 1979 for further information. 12 '— Estimate for the entire San Miguel Island is 48 birds. 280 AREA 501, Santa Maria (cont'd.) Section from U.S.G.S. 1:2A,000 scale map: San MlgTMl lulaaii Ea»t Km 281 502 Los Angeles The map on the facing page is an index to the locations of colonies within map 502, Los Angeles. Note that all colonies on the map are not numbered consecutively from north to south, since many previously unreported colonies have been added since initial colony numbers were assigned by Varoujean (1979). On the pages following this map, all colonies are Hsted sequentially and a detailed map of each is provided. Numbers of breeding seabirds will vary from year to year, numbers of breeding seabirds within this region. Below are the approximate Ashy Storm-Petrel 80 Brown Pelican 2,500 Brandt's Cormorant 100 Double-crested Cormorant 150 Pelagic Cormorant 60 Black Oystercatcher 130 Western Gull 6,700 Pigeon Guillemot 500 Cassin's Auklet 120 * coastal population only. 282 502 Los Angeles N KILOMETERS KEY COLONY NUMBER < 100 BIRDS 100 1 OOO BIRDS 1 OOO - 1OO0O BIRDS 10 OOO - 1 CO OOO BIRDS OVER 1 DO OOO BIRDS Santa Barbara PACIFIC Ventura OCEAN CHANNEL ISLANDS 283 AREA 502, Los Angeles (cont'd.) sample Colony No. . Pelagic Cormorants /PeUgk Coraaoraots Colony name 004) 'Gull Rock^ Z Gear lin La t- Long. '39°3C^20"N,12r35'45"W Number breeding birds Investigators - Survey date / r. ^ -V r 40 (Nelson & Sowls ,6/14/79,8,11 ) A • lines give the most recent or the best estimates available. Stipple lines give additional estimates for other years. ■ Data qual. ■ see text -. Reference \ 42 35 Survey type aerial -j B = haat M = from mainland L = on sire ®Goleta Slough was previously assigned a catalog number because of Light-tooted Clapper Rail nesting. We have not included information on this species in this report. See WUbur (1974). fnn?) ^' Estero was previously assigned a catalog number because of Light-footed Clapper Rail ncNting. [UUc ) We have not included information on this species in this report. See Wilbur (1974). 003) Santa Clara River 34'n4'08"N, 119''15'51"W Least Terns are an endangered species. Populations of Least Terns are surveyed annually. 1 or the most current information contact the California Department of Fish and Came. Least Tern least Tern least Tern 34-30 (Goldwasser, 4-8/80,1) 20-30 (Atwood,4-18/78a) 30-40 (Atwood.4-18/79,L) 12 12 12 (004 ) McGrath Lake was previously assigned a catalog number because of Snowy Plover nesting. Wc have V / not included information on this species in this report. See Page & Stcnzcl (1979). 005) Ormond Beach 34°08'13"N, 119°10'56"W Least Terns are an endangered species. Populations of Least Terns are surveyed annually, for the most current information contact the California Department of Fish and Game. Least Tern Least Tern ieast Tern 0 (Goldwasser, 4-8/80, L) 0 (AtwGod, 4-8/80, L) 12-16 (Atwood,4-8/79,L) 12 12 te) Mugu Lagoon 34°06'08"N, 119°06'04"W fh. m„lf ^'' ^"."^ V^ ^" .^"'^""ew^'J species. Populations of Least Terns are surveyed annually. 1 or the most current mformation contact the CaUfornia Department of Fish and Game. Least Tern least Tern Least Tem X = present 24 (Goldwasser, 4-8/80, L) 20*24 (Atwood, 4-8/80,1) X (Atwood, 4-8/79, L) 284 AREA 502, Los Angeles (cont'd.) J^ Section from U.S.G.S. 1:24,000 scale map: Oxnaxd, Calif. KXD Section from U.S.G.S. 1:24,000 scale map: fltaaard & fmSmX. Mug*, Calif. Km h 285 AREA 502, Los Angeles (cont'd.) 007) Anacapa Island - West 34"00'54"N, 119°2T57"W Anacapa Island - West is the most important breeding site for Brown Pelicans in California. Brown Pelican 2,516 Brandt's Cormorant 0 Double-crested Cormorant 132 Pelagic Cormorant 0 Black Oystercatcher X' Western Gull X Pigeon Guillemot 10 Total 2,758 Brovm Pelican X Brown Pelican 400 Brown Pelican 4,000 Brown Pelican 4,000 Brown Pelican 4,000 Brown Pelican X Brown Pelican 2,544 Brown Pelican 1,104 Brown Pelican 1,080 Brown Pelican 522 Brown Pelican 494 Brown Pelican 832 Brown Pelican 424 Brown Pelican 834 Brown Pelican 152 Brown Pelican 420 Brandt's Cormorant X Brandt's Cormorant 100 Brandt's Cortrorant X Brandt's Cormorant 2 Double-crested Cormorant 30 Double-crested Cormorant 68 Pelagic Corrrorant 2 Pigeon Guilleniot X Z3l (Anderson & Gress,1979) ( /I ,1976) (Anderson & Gress,1979) ( a ,1976-77) ( ,1976-77) ( ,1976-77) ( ,6/23/77) (^shworth;i929 ; Stevens ,t93SV Bond ,1 940) (Ashworth § Thompson, 5/9/30) (Bond, 1935) (Stevens & Harrison, 3/1/36) (Bond & Surw>er,4/16/39) (Jensen, 1962i Ranks, 1963-64; Schreiber & 1967-68) (Risebough,1969) (Sress,1970) (Anderson & Anderson, 1971) (Anderson & Anderson, 1972) (Anderson & Anderson, 1973) (Anderson & Anderson, 1974) (Anderson & Anderson, 1975) (Anderson & Anderson, 1976) (Anderson & Anderson, 1977) (Anderson, 1978) (Ashworth & Thompson, 1928 & 31) (Bond,5/34) (Cross in & Browne 11, 5/ 68) ( /I ,1975) h . ,1977) 4,20 29 4,2C 29 29 29 29 Delong, (Anderson & Sress,1978) ( A. J975) (Wright $ Snyder. 7/6/ 12/ Badger, Hdftna,5/2?/1?) Peyton & ^ Investigators are some or all of the following: Hunt, Pitman, Naughton, Winnett, Newman, Kelly, Briggs and Speich. Only the most significant historical data has been summarized here from intensive studies conducted in the Channel Islands, see Hunt et al. 1979 for further information. /I 20+ estimated for entire Anacapa Island. Estimate is for entire Anacapa, but birds are most likely from West Anacapa. X = present 286 AREA 502, Los Angeles (cont'd.) Section from U.S.G.S. 1:24,000 scale map: Channel Islands Nat. Monument , Calif . Km -^5J Brown Pelicans, Anacapa Island Photo by Frank Gress 287 AREA 502, Los Angeles (cont'd.) 008) Anacapa Island - Middle 34'^00'19"N, 119"23'43"W Brandt's Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Total 4 ( 5,0005f( P^{ 5,008 Zi ,6/23/77) ,1977) ,1976-77) ,1976-77) , . ) 29 29 29 29 29 009) Anacapa Island - East 34"00'41"N, 119"25'26"W Brown Pelican 0/ p{Anders ;on, 1976-77) Black Oystercatcher X^ ^{ /I ,1976-77) Western Gull 200 /a( ,1977) Pigeon Guillemot P^ '{ ,1977) Xantus' Murrelet X ( ,1976-77) Total 200 Ir^n'FeTfeP''''^'''''''"-^"^^ ■"■"■■"'■^- W (Ha11mi4 C 295 AREA 502, Los Angeles (cont d.) 014 Santa Cruz Diablo Pt. Is. - Kinton Pt. 34°0'30"N, lig'^BS'W to 34''3'N, 119°45'W Ashy Storm-Petrel Brandt's Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Cassin's Auklet Total Ashy Storm-Petrel Pelagic Cormorant Pigeon Guillemot Tufted Puffin X = present 20 84 234 X X X ( n ( ( ( ( ( ( ,7/15/76) ,1977) ,1976) ,1977) ,1977) ,1977) ,1977) (Wright & SnyderJ912; Dickey, 1913) (Dawson, 1923) (Wright & Snyder, 191 2) (Wright & Snyder, 191 2) 29 25 29 29 29 29 29 29 29 29 29 11 Investigators are some or all of the following: Hunt. Pitman, Naughton, Winnett, Newman, Kelly, Briggs and Speich. Only the most significant historical data has been summarized here from intensive studies conducted in the Channel Islands, see Hunt et al. 1979 for further information. a 11 100 estimated for entire Santa Cruz Island, including Gull Island (524 001), Scorpion Rock (502 010) and "Sppit" (502 013). 400 estimated for entire Santa Cruz Island. 296 AREA 502, Los Angeles (cont'd.) o 4-l o • •H O •u • o w (U . M C3 297 524 Long Beach The map on the facing page is an index to the locations of colonies within map 524, Long Beach. Note that all colonies on the map are not numbered consecutively from north to south, since many previously unreported colonies have been added since initial colony numbers were assigned by Varoujean (1979). On the pages following this map, all colonies are Usted sequentially and a detailed map of each is provided. Numbers of breeding seabirds will vary from year to year. Below are the approximate numbers of breeding seabirds within this region. Ashy Storm-Petrel 300 Black Storm-Petrel 150 Brown Pelican X Brandt's Cormorant 730 Double-crested Cormorant 150* Pelagic Cormorant 10 Black Oystercatcher 30 Western Gull 4,700 Pigeon Guillemot 120 Xantus's Murrelet 3,200 Cassin's Auklet 400 X = present * coastal population only. 298 524 Long Beach 299 AREA 524, Long Beach (cont'd.) sample ColonyNo. Colony name 004 'Gull Rock^ Lat.-Long. '39°3C^20"N,121"35;45"W Number breeding birds Investigators Survey date Pelagic Cormorants /PfeUgtc C6il*#ionaits / r. ^ -V c 40 (Nelson & Sowls, 6/14/79, B, II ) 48 ({kbOft»e,6/5/69) /* L. dear lines give the most recent or the best estimates available. Stipple lines give additional estimates for other years. ■ Data qual. - see text \ Reference Survey type 42 35 aerial boat from mainland on site (m) Gull Island 33°57'01"N, 119°49'28"W Ashy Storm-Petrel Brandt's Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Xantus' Murrelet Cassin's Auklet Total Brandt's Cormorant 8rar{dt*s Connorant l^elaglc Cormorant 2 134 0 8 170 2 150 466 46+ 110 8 ZI a ,4/12/77) ,1977) ,1976-77) ,1977) ,1977) ,1976-77) ,1975-77) ,1975) .1976) ,1975) 29 29 29 29 29 29 29 29 29 29 LI Investigators are some or all of the following: Hunt, Pitman, Naughton, Winnett, Newman, Kelly, Briggs and Speich. Only the most significant historical data has been summarized here from intensive studies conducted in the Channel Islands, see Hunt et al. 1979 for further information. 300 AREA 524, Long Beach (cont'd.) Gull Island right Section from U.S.G.S, 1:24,000 scale map: Soita Cns Island B Km H -i 301 AREA 524, Long Beach (cont'd.) (002) Venice Beach and Playa del Rey 33°57'30"N, n8°27'30"W Least Terns are an endangered species. Populations of Least Terns are surveyed annually. For the most current information contact the California Department of Fish and Game. Least Tern 300-330 (Atwood, 4-8/80, L) 12 Least Tern 170-210 (Atwood, 4-0/78Vi) 12 least Tern 196-240 (Atwood, 4-8/79,L} 12 fOOSj Terminal Island 33"57'30"N, 118^27' 30"W Least Terns no longer use this site for nesting. (004) Anaheim Bay and Surfside Beach 33°44'05"N, 118°05'34"W Least Terns are an endangered species. Populations of Least Terns are surveyed annually. For the most current information contact the California Department of Fish and Game. Least Tern 80-96 (Atwood,4-8/80^L Least Tern 12 (Atwood, 4-8/79**' 302 AREA 524, Long Beach (cont'd.) Plava Seal Beach, Calif. Kb 303 AREA 524, Long Beach (cont'd.) 005) San Gabriel River 33°45'12"N, 118°06'15"W Least Terns are an endangered species. Populations of Least Terns are surveyed annually. For the most current information contact the California Department of Fish and Game. Least Tern "^Ist Tern Least Tern 24-30 (Atwood,4-8/80,L) 120-130 (Atw<«Kl»4-8/78,L) lDO-110 (Atwood,4-8/79,L) 12 12 12 006) Bolsa Chica Beach 33°42'05"N, n8°03'05"W Least Terns aie an endangered species. Populations of Least Terns are surveyed annually. 1 or the most current information contact the California Department of Fish and Game. Least Tern least Tern Least Tern 40-52 (Atwood, 4-8/80, L) 0 (Atwood, 4-8/78,1) 68-92 (Atwood,4-8/79,L} 12 12 12 304 AREA 524. Long Beach (cont'd.) Section fron U.S.G.S. 1:24,000 scale map: Seal Beach, Calif. Ka 305' AREA 524, Long Beach (cont'd.) 007) Shag Rock 33°29'15"N, n9°02'05"W Western Gull Xantus' Murrelet Total 20 { 30 ( 50 /I ,1976) .1977) 008) Santa Barbara Island 33°28'37"N, 119°02'03"W Black Storm-Petrel Ashy Storm-Petrel Brown Pelican Brandt's Cormorant Double-crested Cormorant Pelagic Cormorant Black Oystercatcher Western Gull Pigeon Guillemot Xantus' Murrelet Cassin's Auklet Total Brovm Pelican Brown Pelican Brown Pelican Brown Pelican Brown Pelican B^own Pelican Brandt's Cormorant Brandt's Cormorant Brandt's Connorant Brandt's- Cormorant 120 130 250 174 102 14 4 12 2,300 90 2-4,000 150 6,220 none 50 300-400 X none none X 92 52 146 X Double- ores ted Connorant Double-crested Connorant none Double-crested Confiorant 132 Double-crested Corttiorant 20 Pelagic Cormorant X Pelagic Corn»rant 2 Pelagic Cornwrant none Western Gull X Western Gull 1 ,0{X) V/estern Gull 3,000 Western Gull 2,324 Western Gull 2,230 Western Gull 1,622 Wester?) Gull 850 Pigeon Gu111erm)ts X Xantus' Murrelet X Cassin's Auklet X Cassin's Auklet none Cassin's Auklet none Tufted Puffin ? X = present ( ZI ,1976-77) ( I M976-77) (Gress,1980) ( 11 ,1977) ( ,1977) ,1977) ,1977) ,1975-78) ,1976) ,1977) ,1977) 29 29 20 29 29 29 29 29 29 29 29 (Grinnel,T89T) ■■■■■■■■■-■■-■■■-■■■■■■■■■■■■■-■■■■-■■■- (Willet, 6/14/11) (Wright & Snyder, 7/2/1 2) (Peyton, 5/ 7/ 14; Schrelber & Delong,1967) ( a .1975-77) (Gress, 1978- 1979) {Grinnell,1897; Howell, 1908) (Oehl, 7/11/74) ( ZI .1975) I .1976) (Cooper, 1863; Gr1nnel,l897; Peyton, 1914; Wyisan, 1920+27; Sufl»ner,1939) (Crossin & Brownell ,5/68) (Hunt & Hunt, 7/2/72) ( a .1976) {Grinnell,1897; Pemberton,1927) ( ZL ,1975) { I ,1976) (6rinne11,1897) (ChaiBl3ers,1889) (Hunt & Hunt, 7/7/72) ( a .1975) ,1976) .1977) ,1978) (GrinneU,1897; $urRner,1939; Small. 1960) (Wright & Snyder, 7/3/12) (Cooper, 1863; Gr1nnel,1897) (Howell, 1908; Willet, 1911; Wright & Snyder, 191 2) (SuRmer & Bond, 1939; Hunt & Hunt, 1972) (6r!nnel.l897) 306 AREA 524, Long Beach (cont'd.) 009 -\- 33O3O' 119002 •SO" Santa Barbara Isia c. fArch Point U .S COAST GUARD HK.SEKVATION Rjiiger Station dndlCai7>pgfound -(W n^fX'sutii -|-33**27'30" 119002 '30" PA C I F I C Section from U.S.G.S. 1:24,000 scale map: Channel Islands Nat. Monument, Calif. Km h 307 AREA 524, Long Beach (cont'd.) 009) Sutil Island 33°28'50"N, 119°02'50"W Black Storm-Petrel 20-30 /I ,1976-77) Ashy Storm-Petrel 40-50 ( ,1976-77) Brandt's Cormorant 152 ,1977) Double-crested Cormorant 120 ,1977) Pelagic Cormorant 4 .1977) Black Oystercatcher 4 ,1977) Western Gull 150 ,1976) Pigeon Guillemot 30 .,1976) Xantus' Murrelet 150 ,1977) Cassin's Auklet 70 , 6/27/76, L) Total 750 »raft«(it*s Connorant 80 1 :vkh1,mV74) ' ^ Brandt's Connorant 186 [ /I .1975) Brandt's Cormorant 140 [ a .^976) Double-crested Cormorant 60 : Zl .1976) Cassin's Auklet 200 (wnie tt,6/14/n,L) 29 29 29 29 29 29 29 29 29 29 29 29 ■29 29 29 a Investigators are some or all of the following: Hunt, Pitman, Naughton, Winnett, Newman, Kelly, Briggs and Speich. Only the most significant historical data has been summarized here from intensive studies conducted in the Channel Islands, see Hunt et al. 1979 for further information. Sutil Island Photo by George Hunt 308 AREA 524, Long Beach (cont'd.) + 33«30' 119002*30!^ Santa Barbara Island Shag Rock j:?. fArch Point S COAST GUARD RESERVATION er Station Campground 008 U S COAST GUARD RESERVATION Sutil Island + S3*J!7*30' Mf •©! »8e" JP A C I F I C Section from U.S.G.S. 1:2A,000 scale map: Channel Islands Nat. MonuBient, Calif. Km I > I 0 h 1 309 AREA 524, Long Beach (cont'd. 010) Bird Rock 33°27'04"N, n8°29'04"W Brandt's Cormorant Western Gull Xantus' Murrelet Total ;^randt's Cortnorant ^'Brandt's Conrtorant ^Western Gull Iftestem Gull ^stem Gull Ifestern Gull ptestem Gull Itestem Gull ^Xantus* Hurrelet X = present 0 52 0 52 X nom X 48 50 20 58 50-60 X ( 11 ( I ( I ,1975-76) ,1976) ,1976-77) (W11 let. 4/11/04) (Jehl, 7/9/74) {Grinneini897) (Harper, 1965) (Harper, 1966) (Jehl, 7/ 1974) (Hand, 1974) ( a '■J^^s) (Bleitz.1967) 29 29 29 29 29 29 29 29 29 29 29 29 il Investigators are some or all of the following: Hunt, Pitman, Naughton, Winnett, Newman, Kelly, Briggs and Speich. Only the most significant historical data has been summarized here from intensive studies conducted in the Channel Islands, see Hunt et al. 1979 for further information. 310 AREA 524, Long Beach (cont'd.) 311 AREA 524, Long Beach (cont'd.) on) San Nicolas Island 33°14'30"N, 119°30'30"W Brandt's Cormorant 290 ( Black Oystercatcher 2 ( Western Gull 1 ,800 ( Total 2,092 Brandt's Co^fm)rant X ( Irandt's Connorant 1,200 ( Brandt's Connorartt 1,200 ( Brandt's Cormorant 970 ( Brandt's Connorant 1,230 ( Brandt's Connorant 266 ( Brandt's Connorant 340 ( Western Gull 6,000 ( Iftestern Gull 1,200 ( X = present a ,1977) ,1977) ,1975-77) Gaylord,1897) Schreiber, 6/1 7/68) Anderson, 6/14/72) Anderson, 1973) Hunt & Leach, 5/ 22/ 74) a. ,1975) IX ,1976) Delong J/29/67) Schretber,1968) 29 29 29 29 29 29 29 29 29 29 29 29 11 Investigators are some or all of the following: Hunt, Pitman, Naughton, Winnett, Newman, Kelly, Briggs and Speich. Only the most significant historical data has been summarized here from intensive studies conducted in the Channel Islands, see Hunt et al. 1979 for further information. 312 AREA 524, Long Beach (cont'd.) 313 AREA 524, Long Beach (cont'd.) 012] Bird Rock and N.W. San Clemente Is. 33°02'N, 118°35'W Brandt's Cormorant 10 ( /I ,1976) 29 Black Oystercatcher 2 ( ,1977) 29 Western Gull 56 ( ,1976) 29 Total 68 Brandt's Cormorant X (Linton, 1907; Jehl,1973) 29 Western Gull X {Jehl,1973) ^^ ,|||||rO,|iiU,,,.,,,,,,,,,, 62 ( ^ a975} mmmmmmmm ^^ X = present ^ Investigators are some or all of the following: Hunt, Pitman, Naughton, Winnett, Newman, Kelly. Briggs and Speich. Only the most significant historical data has been summarized here from intensive studies conducted in the Channel Islands, see Hunt et al. 1979 for further information. 314 AREA 524, Long Beach (cont'd.) 315 AREA 524, Long Beach (cont'd.) [013; Seal Cove to Lost Point 32°52'N, llS^Sl'W to 32^54' 10"N, 118°32'20"W Brandt's Cormorant 30 ( Z] ,1976) ,1976-77) 2i ,1976-77) 1'? ,1976) 2? Black Oystercatcher 2 ( Western Gull 56 ( Xantus' Murrelet _X^ ( Total 88 _ ,._ 8ran<^t's Cormorant X (Leattierwood & Coulombe,1972; Jones & JehlJ9? Wes tern Gul 1 X (Oeh 1 , 1 973 1 X = present ^ Investigators are some or all of the following: Hunt, Pitman. Naughton, Winnett, Newman, Kelly, Briggs and Speich. Only the most significjnt historical data has been summarized here from intensive studies conducted in the Channel Islands, see Hunt et al. 1979 for further information. 316 AREA 524, Long Beach (cont'd.) ■SB^ h Section from U.S.G.S, 1 : 24, 000 scale map: Saa Cl«a«itte tulmtd Central Kb 317 525 Santa Ana The map on the facing page is an index to the locations of colonies within map 525, Santa Ana. Note that all colonies on the map are not numbered consecutively from north to south, since many previously unreported colonies have been added since initial colony numbers were assigned by Varoujean (1979). On the pages following this map, all colonies are hsted sequentially and a detailed map of each is provided. 318 525 Santo Ano KILOMCTCRS < 100 Btnos 100 - 1,000 BIROS 1.000 - 10.000 BtROS 10.000 - 100,000 Bu...,. ;;Sftv::;:-::-;->>;-:^:;^ft-:Wy^ 12 12 12 (002) Newport Bay 33°38'46"N, n7°53'08"W Least Terns are an endangered species. Populations of Least Terns are surveyed annually. For the most current information contact the California Department of Fish and Game. Least Tern least Tern Least Tern 4-10 (Atwood, 4-8/80, L) 15-20 (Atwood, 4-8/78,L) 12-14 (Atwood, 4-8/79,1) 12 12 12 (003) Santa Margarita River 33°13'57"N, 117°24'37"W Least Terns are an endangered species. Populations of Least Terns are surveyed annually. For the most current information contact the California Department of Fish and Game. Least Tern Least Tern Least Tern 80 (Copper and Bel luomini ,4-8/80, L) 60-80 (Unitt, 4-8/78, L) 64-80 (Unitt, 4-8/78,1) 12 12 12 320 AREA 525, Santa Ana (cont'd.) Section from U.S.G.S. :24,000 scale map: Newport Beach, Ca. "f^ \jlJ" Section from U.S.G.S. 1:24,000 scale map: Newport Beach and Tustln, Calif. Kb I » o Oceanslde, Calif. 321 AREA 525, Santa Ana (cont'd.) 004) Agua Hedionda 33°08'45"N, n7°19'30"W Least Terns are an endangered species. Populations of Least Terns are surveyed annually, I or the most current information contact the California Department of Fish and Game. Least Tern 16-20 (Copper, 4-8/80, L) -15 Least Tern 22-30 (Unttt, 4-8/78, 1) •, 13 Least Tern 46-56 (Copper, 4-8/7d»L) ^||HK|WWUUH ^s 005) Batiquitos Lagoon 33°05'25"N, n7°17'30"W Least Terns are an endangered species. Populations of Least Terns are surveyed annually. Kor the most current information contact the ralifornia Department of lish and Game. Least Tern 50-60 (Copper, 4-8/80, L) 22 least Tern 44>54 (Unitt,4-8/7a,L} mmmmmmggjgmm^ ^^ least Tern 76-80 ( C op per» 4-8/79,1) :&■■■■■■■ 13 (ooe) San Eli jo Lagoon 33°00'58"N, n7°16'52"W Least Terns are an endangered species. Populations of Least Terns are surveyed annually. Tor the most current information contact the California Department of Fish and Game. Least Tern 34 (Copper, 4-8/80, L) 13 least Tern IB (Unitt»4*8/78»l) -^2 least Tern . 24 (Copper, 4-8/79,1) 12 322 AREA 525, Santa Ana (cont'd.) Section from U.S.G.S. 1:2A,000 scale map: San Lula Rey, Calif. Section from U.S.G.S. 1 :24,000 scale map: Enclnltas, Calif. Km 0 0 Section from U.S.G.S. 1:24,000 scale map: Znclnltaa, Calif. -• Kark"! Solana BeachI Kb 323 AREA 525, Santa Ana (cont'd.) 007) Aliso Creek 33°30'35"N, n7°45'12"W Least Terns are an endangered species. Populations of Legist Terns are surveyed annually. Tor the most current int'ornialion contact the California Department of I'ish and Game. Least Tern 100 (Copper, 4-8/80, L) ^ 12 ■^m tern -■'■■■■ --^^^^^^^^^^^ (Copper,4-8/79,L J '^m ^^ (OOS) Buena Vista Lagoon 33°10'30"N, n7°2ri5"W Least Terns arc an endangered species. Populations of Least Terns are surveyed annually. 1 or the most current information contact the California Department of lish and Game. Least Tern 2 (Copper, 4-8/80, L) 12 324 AREA 525, Santa Ana (cont'd.) Section from U.S.G.S. 1:2A,000 scale map: Laguna Beach & ^ij San Juan Caplstrano Km 325 545 San Diego The map on the facing page is an index to the locations of colonies within map 545, San Diego. Note that all colonies on the map are not numbered consecutively from north to south, since many previously unreported colonies have been added since initial colony numbers were assigned by Varoujean (1979). On the pages following this map, all colonies are listed sequentially and a detailed map of each is provided. 326 545 San Diego 327 AREA 545, San Diego (cont'd.) sample ColonyNo. Colony name La t. -Long. 004 'Gull Rock^ '39°35'20"N,121°35;45" W Number breeding birds Investigators Survey date / r .A. -V r Pelagic Cormorants 40 (Nelson & Sowls ,6/14/79,8,11) / ^ Xsurvey p Z. Clear lines give the most recent or the best estimates available. ■ ~* " Stipple lines give additional estimates for other years. ■ Data quai ■ see text \ Reference type 42 35 aerial boat from mainland on site @ Los Penasquitos Lagoon 32°55'49"N, 117°14'54"W Least Terns axe an endangered species. Populations of Least Tems aie surveyed annually. For the most current information contact the California Department of Fish and Game. Least Tern Least Tern least Tern 30 (Copper, 4-8/80, L) 32 (Copper, 4-^8/79 »L) 12 12 12 328 AREA 545, San Diego (cont'd.) Section from U.S.G.S. 1:24,000 scale map: D^ Mar. Calif. 329 AREA 545, San Diego (cont'd.) (002) Mission Bay 32°46'42"N, n7°13'46"W Least Terns are an endangered species. Populations of Least Terns axe surveyed annually. I or the most current information contact the California Department of Fish and Game. Least Tern Least Tern Least Tern 262-266 (Copper, 4-8/80, L) 246-328 {Unitt,4-8/78,L) 222 {Copper,4-8/79»L) 12 12 12 Least Terns Photo by Bill Beebe, Santa Monica Evening Look 330 AREA 545, San Diego (cont'd.) Entrance Cfia^ K7 ,^ Beach I Par r.eW- Section from U.S.G.S, 1:24,000 scale map: La Jolla, Calif. Kn I 331 AREA 545, San Diego (cont'd.) 003) North San Diego Bay 32°44'N, 117°12'W Least Terns aie an endangered species. Populations of Least Terns are surveyed annually. For the most current information contact the California Department of Fish and Game. Least Tern Western Gull Total Least Tern least Tern 342 20 362 182-190 386-400 (Copper, 4-8/80, L) (Copper & Jorgensen, 4-8/80, L) (Unitt,4-8/78,l} {Copp€r,4-8/79»L) 12 16 12 12 004 Silver Strand Beach was previously assigned a catalog number because of Snowy Plover nesting. We have not included information on this species in this report. See Page & Stenzel (1979). 332 AREA 545, San Diego (cont'd.) 333 AREA 545, San Diego (cont'd.) (005) South San Diego Bay 32°36'N, 117°07'W Least Terns are an endangered species. Populations of Least Terns are surveyed annually. For the most current information contact the California Department of Fish and Game. Least Tern 130 Forster's Tern 2,000 Elegant Tern 900 Caspian Tern 900 Black Skimmer 70-80 Total 4,010 least Tern 74-78 Least Tern 122-140 Black Skinsner 2 Black Skimmer 5 itmmfffmm:' (Copper & Evans, 4-8/80, L) (Copper & Evans, 4-8/80, L) (Copper & Evans, 4-8/80, L) (Copper & Evans, 4-8/80, L) (Copper & Evans, 4-8/80, L) {Unitt, 4-8/80. L) (Copper, 4-8/79, I) (Evans, 1976, L) (Evans,4-B/77,L) 12 12,16 12,16 12,16 12,16 12 12 12,16 12,16 Caspian Terns 334 AREA 545, San Diego (cont'd.) -?i M ay| Parks U-o-tliJir^ Section from U.S.G.S. 1:24,000 scale map: Imperial Beach, Ca. 335 AREA 545, San Diego (cont'd.) (ooe) Tijuana River Mouth 32°33'25"N, n7°07'48"W Least Terns are an endangered species. Populations of Ueast Terns are surveyed annually. For the mosj current information contact the California Department of lish and Game. Least Tern 50 (Copper, 4-8/80, L) 12 least Tern 16-24 (Unitt, 4-8/78, L) ^^^^ffi| 22 Least Tern 50-60 (Copper, 4-8/79, L) I^HI ^^ (007) Del Mar 32°58'10"N, n7°14'45"W Least Terns are an endangered species. Populations of Least Terns are surveyed annually. For the most current information contact the California Department of Fish and Game. Least Tern 10 (Denson,1980,L) 12 008) Sweetwater River 32°38'30"N, 117°06'35"W Least Terns are an endangered species. Populations of Least Terns are surveyed annually. For the most current information contact the California Department of Fish and Game. Least Tern 24-30 (Copper, 4-8/80, L) 12 Least Tern 94 (Unitt, 4-8/78, L) 12 Least Tern 48-56 (Copper, 4-8/79, L) 12 336 AREA 545. San Dieoo (cont'd.) Section from U.S.G.S, 1 :24,000 scale map: Section from U.S.G.S. 1:2A,000 scale map: NatlMid. Clt7. C«. 1 ©^0| 337 AREA 545, San Diego (cont'd.) 009) La Jolla 32°5rN, 117°15'55"W Brandt's Cormorant 6 (Everett,! 980, L) 16 Western Gull _4 ( Everett, 1 980, L) 16 Total 10 338 AREA 545, San Diego (cont'd.) 2 View Poi 5*' SCRIPPS INSTITUTION OF OCEANOGRAPHW (UNIV OF CALIFl , V »» Point La Jol Boomer Beac Rocky Poi 339 fwff 340 REFERENCES Italicized numbers in the margin ( 1 ,2, etc.) correspond to italicized numbers in the maps and tables and in the breeding chronology figures in the species accounts. Ainley, D.G. , pers. comm. Point Reyes BirdfObservatory, 4990 ShoreUne Highway, Stinson Beach, CA 94970. 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Saving oiled seabirds: a manual for cleaning and rehabilitating oiled waterfowl. Amer. Petroleum Inst., Wash. DC. Williams, L. 1927. California Brown Pelicans nesting at Point Lobos, Monterey County, California. Condor 33:66-69. Williams, L. 1931. Further notes on California Brown Pelicans at Point Lobos, California. Condor 33:66-69. Winnett, K.A., K.G. Murray, and J.C. Wingfield. 1979. Southern race of Xantus' Murrelet breeding on Santa Barbara Island, California. Western Birds 10:81-82. Yocom.CF., and S.W. Harris. 1975. Birds of north western^. California. Humboldt State Univ., Areata, CA. 44 Zerlang, L., and T. Eraser. 1940. A large set of the Black Oystercatcher. Condor 42:264. 350 APPENDIX A: DATA ARCHIVING This catalog is a summary of data from many sources and more detailed information on many of these sites is available. This information may include more detailed maps, notes on re- productive success, vegetation, marine mammals, pelagic birds in the area, land ownership, access, management problems, and photographs. We have provided this section for those who may desire access to this information. Field data collected by the U.S. Fish and Wildhfe Service in 1979 and 1980 were recorded onto Colony Status Records (Figure 5) or into a field notebook arranged by species. Other data compiled in this catalog are referenced as to their sources. This catalog can serve as an index to the Colony Status Records since their numbering systems are identical. Copies of the Colony Status Records and our field notebook have been deposited at: Bureau of Land Management Pacific OCS Office 1 340 W. 6th Street Los Angeles, CA 90017 CaUfornia Academy of Sciences Golden Gate Park San Francisco, CA 94118 Cahfomia Dept. of Fish and Game WDdlife Investigations 1416 Ninth Street Sacramento, CA 95814 Patuxent Research Lab U.S. Fish & Wildhfe Service Laurel, MD 20810 Colonial Bird Register Laboratory of Ornithology Cornell University 1 59 Sapsucker Woods Road Ithaca, NY 14850 U.S. Fish & Wildhfe Service Lloyd 500 Building, Suite 1692 500 N.E. Multnomah Street Portland, OR 97232 Photographs will be of great value in the future, particularly for evaluating changes in habitat and changes in populations of Brandt's Cormorants and Common Murres. Some black and white prints and some color shdes are included with each set of Colony Status Records. Nearly all of these photographs were taken during our study. All remaining photographs and all black-and-white negatives taken during our study have been divided between the U.S. Fish and Wildlife Service office in Portland and the California Academy of Sciences in San Francisco. These were divided so that nearly identical photographs are at both locations. Important photographs from other sources have also been copied and included when possible or reference to their existence has been made on the Colony Status Records under the section "Photo Coverage". More historical data probably exist than have been summarized in this study and future studies may obtain much new information. We consider this study a step toward a better under- standing of marine birds and we welcome any comments, corrections, or additions to our files or to this report. Comments should be addressed to our Portland office. 351 Colony Status Record iih •^ 1 1 il 1 re Se rvice Area Number 477 007 Observer (s) Nelson, Sowls Colony y.ax.e Pledras Blancas Rock Field No. _ .Map Pipdras Blancas. Ca, Lat .35^39'52" Lo,g>21°17 ' 18'V,^^/26 9:49^f 6/26/79 - boat Weather 6/26 nvp.rrasr ,1 ip.hr breeze from NW. swells 6', waves T. 1. 1 .8/2/79 - aerial No, Nests No. Birds Remarics (estimar.ed tninimum £ maximum, egg & chick status, etc.) Fork-tailed Storv Petrel Leach's Scorn Pecre* Aahy Stom Petrel Brown Pelican Corvoranc (unld.) Brandt's Coraorant Double-crested Cormorant Pelanlc Cormorant Black Oystercatcher f^ull (unld.) Claucous-wlnged Cull Western Oull Least Tern Forscer's Tern Caspian Ten> Coonon Hurre Pigeon CuiUeMOt Karbled Murrelet Xancua ' Murrelet Cassln's \uklec Rhinoceros Auklet Tufted Puffin i: 28. E 25 rnoRf rooBt r. 680 1360 f count made from aerial slide taken 8/2/79. ' Most nests In a "bowl" on the S.W. side of..' t-hff Island - these cannot be counted from the mainland or from a boat, nata qual. = I I . mrHfi Mere rounted that appeared to be on territories, number estimated conservative. Data quality - III. 15 nests est, on N. side. 9 nests est, on vestem side & 4 nests est. on S.E. side. t Good habitat, 24 birds either on the l8lan4 or just offshore. J One seen flying N. from Island on 6/25 In the. PifPti eastern sides of the Island. Boat distance must be maintained to avoid disturbance & -Ifi ,♦, I landing on island at this time not posslbli : / l^ wltli ■L-50'29"W 256 404 037 38°22'30"N,123°05'W 174 325 047 41°40'22"N,124''08'30"W 94 429 031 37'=24'15"N,122°25'30"W 204 404 041 38°11'N,122°58'W 178 454 003 36° 49'04"N,1 2 1° 46'30"W 214 325 040 40°30'38"N,124°23'40"W 40 325 010 41°35'40"N,124°06'36"W 70 429 012 37°41'53"N,123°00'05"W 188 404 022 38°47'45"N,123°35'20"W 158 404 003 38°48'N,123°35'31"W 146 325 023 41°03'34"N,124''09'39"W 80 325 011 4P31'3r'N,124°05'00"W 70 325 050 41°37'00"N424'^07'10"W 94 477 034 35°10'26"N,120°43'26"W 256 379 022 39°2rN,123°48'45"W 128 404 030 38"33'N,123°18'45"W 168 379 006 39°18'28"N,123°48'49"W 112 325 020 41°04'32"N,124°09'48"W 78 429 035 37°03'N,122°15'W 206 454 033 36°12'20"N,121'=44'15"W 232 429 020 37»28'12"N,122°04'52"W 194 404 004 38°45'04"N,123<^31'42"W 148 454 023 36''31'25"N,121°56'47"W 226 524 001 33°57'01"N,119°49'28"W 300 404 035 38°25'30"N,123°07'10"W 172 429 025 37°52'35'TS[,122°37'W 196 325 054 4r03'N,124°08'W 100 379 017 39''42'20"N,123°38'30"W 124 501015 34°04'N,120°22'W 278 379 012 39°55'30"N,123°57'10"W 118 404 028 38°36'30"N,123P22'10"W 166 367 Appendix C (Continued) Name Hunter Rocks Huntington Beach Hurricane Point Rocks "Iverson Landing" Kibesillah Rock La Cruz Rock La JoUa Lafler Rock & Mainland Lake Talawa Beach "Larus Rock" "Last Chance Rock" Limantour Estero Lion Rock Lion Rock at Point Sal "Little Pewetole Rock" Little River Rock Lobos Rocks Lobos Rock & Lands End Lopez Rock Los Panasquitos Lagoon "Luffenholtz Rock" Mallo Pass Creek Martin's Beach McWay Rocks Mendocino Mendocino Bay Millers Point Rocks Mission Bay Mistake Point to Big White Rock "Moat Cove" "Molera Rock" Morro Rock and Pillar Rock "Mr'rp Rock" Mugu Lagoon Muir Beach Headlands to Tennessee Cove Newport Bay "Newrport Rocks" "North Pismo Beach Rocks" North San Diego Bay "Northwest Cape Rocks" Oakland International Airport Old Areata Wharf Ormond Beach Oso Flaco Lake Palmer's Point to Scotty Point "Partington Ridge North" "Partington Ridge South" "Peaked Hill" Pecho Rock Pescadero Rock Pfeiffer Point Piedras Blancas Pier 45 Pigeon Point Pillar Point Pilot Rock Pirmacle Point Area Pinnacle Rock Colony Lat., Long. Page 325 002 41°57'22"N,124°12'4r'W 62 525 001 33°38'43"N,117°59'02"W 320 454 011 36°2r40"N,121°54'25"W 220 404 002 38°50'39"'N,123°38'37"W 144 379 004 39°34'49"N,123^46'51"W no 477 006 35°42'23"N,121°18'45"W 242 545 009 32°5rOO"N,117°15-S5"W 338 454 034 36°12'N,121°43'36"W 232 325 005 41°50'03"N,124°13"18"W 64 477 014 35°57'44"N,121°29'0r'W 246 325 049 41°38'05"N,124°07'30"W 94 404 013 38°Or52"N,122°55'53"W 154 477 011 35°3rOl"N,120P52'15"W 244 501 008 34°53'55"N,12(f 39'50"W 272 325 022 41°04'N,124°09'W 78 325 035 41°02'08"N,124°07'16"W 84 454 025 36°27'18"NJ21''56'10"W 228 429 029 37°47'15"N,122°30'20"W 200 454 020 36"01'34"N,121°34'46"W 226 545 001 32°55'49"N,117°14'54"W 328 325 054 41°03'N,124°08'W 100 379 034 39°02'20"N,123°41'50"W 140 429 033 37°22'N,122°24'30"W 204 454 015 36°09'46"N,121°40'44"W 22"> 379 025 39°18'10"N,123°47'50"W 132 379 026 39°17'30"N,123°47'40"W 132 429 002 37^58'53"N,122°48'35"W 184 545 002 32°46'42"N,117°13'46"W 330 379 014 39°5r30"N,123°53'30"W 120 404 018 38°53'10"N,123°4rW 156 454 030 36°16'45"N,121°5r30"W 232 477 026 35°22'13"N,120°52'08"W 252 325 054 41 03'N,124°08'W 100 502 006 34°06'08"N419°06'04"W 284 429 026 37°5rOO"N,122°33'45"W 198 525 002 33'^8'46"N,117°53'08"W 320 379 021 39°34'49"N,123°46'51"W 126 477 036 35°08'57"N,120°39'23"W 258 545 003 32°44'N,117°12'W 332 404 032 38°30'40"N,123°15'17"W 170 429 011 37°43'21"N,122°13'46"W 188 325 038 40°50'59"N,124°05'58"W 86 502 005 34°08'13"N,119°10'56"W 284 477 037 35°01'42"N,12CP37'40"W 258 325 052 41°07'N,124°09'W 96 454 014 36°10'06"N,121°41'14"W 222 454 035 36°00'N,121°40'40"W 234 404 034 38°25'45"N,12:f 07'10"W 172 477 032 35'^10'45"N,120°49'00"W 256 454 022 36^33'43"N,121°56'33"W 226 454 032 36°35'18"N,121°47'35"W 232 477 007 35°39'52"N,12I°17'18"W 242 429 037 37°48'34"N,122°25'W 208 429 034 37°10'55"N,122°23'20"W 206 429 030 37°23'N,122°29'55"W 202 325 026 41°03'06'N,124°09'09"W 82 454 007 36°31'25"N,121°57'14"W 216 404 039 38°18'20"N,123°OnO"W 178 368 Appendix C (Continued) Name Colony Lat., Long. Page Plaskett Rock 477 002 35°55'14"N,121°28'41"W 238 Plaskett Rock, small rocks and mainland N. and E. of 477 001 35°55'16"N,121°28'22"W 238 Point Arena 404 017 38°57'20"N,123°44'30"W 156 Point Arguello 501011 34°38'N,120°38'49"W 274 Point Bennett, San Miguel Island 501 014 34°2'N,120°3'30"W 276 Point Bonita 429 008 37°48'55"N,122°31'40"W 186 Point Buchon 477 009 35°15'20"N,121°53'58"W 242 Point Cabrillo to Jack Peters Gulch 379 024 39°20'N,123°49'W 130 Point Conception 501013 34°26'54"N,120°28'13"W 274 Point Diablo Bluffs and Needles 429 028 37°49'30"N,122°29'W 200 Point No Pass 379 011 39°58'40"N,123°59'40"W 118 Point Piedras Blancas, two rocks south of 477 024 35°39'30"N,121°16'02"W 250 Point Resistance 429 024 37°59'55"N,122*'49'40"W 196 Point Reyes 429 001 37°59'26"N,123°59'24"W 182 Point Reyes Beach 404 012 38°04'00"N,122°58'47"W 154 Point San Simeon 477 038 35°38'N,12fl2'W 258 Point St. George 325 057 41°47'N,124°15'W 104 Point St. George Lighthouse 325 044 41°50'N,124°22'W 92 Point Sur 454 012 36°18'22"N,121°53'39"W 220 Prince Island 325 003 4l''57'04"N,124°12'4r'W 64 Prince Island 501004 34°03'29"N,120P 20'00"W 266 Prisoner Rock 325 027 41°03'07"N,124°08'34"W 82 "Puffm Rock" 325 021 41°04'18"N,124°09'32"W 78 Punta del Ano Nuevo 429 022 37°07'07"N,122°20'09"W 194 "Pup Rock and Adjacent Mainland" 477 028 35°13'00"N,120°52'11"W 254 "Radar Station Rocks" 325 051 41°33'30"N,124°06'00"W % "Ragged Point Lodge Colony" 477 022 35°46'53"N,121° 19'56"W 250 Red Rock 429 039 37°55'45"N,122°25'50"W 210 Redding Rock 325 013 41°20'29"N,124°10'26"W 72 Redwood Gulch, point north of 477 017 35°50'20"N,121°24'04"W 246 "Redwood Gulch Rock" 477 005 35°49'32"N,121°23'29"W 242 Redwood Gulch, Seastack south of 477 018 35°49'30"N,121° 23'22"W 248 "Rock R" 325 048 41°40'00"N,124°08'30"W 94 "Rockland Landing North" 454 037 36°00'57"N,121°32'30"W 234 "Rockport Rocks" 379 001 39°44'10"N,123°50'00"W 108 Rocky Point 454 028 36°24'06"N,121°54'40"W 230 Rocky Point 501012 34°33'45"N,120°38'11"W 274 "Russian Gulch" 404 033 38°28'N,123°09'36"W 170 "Russian River Rocks" 404 005 38°27'14"N,123°08'34"W 148 Salmon Creek 404 007 38°20'27"N,123°03'58"W 150 "Sahnon Creek" 477 020 35°48'31"N,121°21'47"W' 248 Salmon Creek, arched peninsula south of 477 021 35°48'05"N,121°21'14"W 248 San Elijo Lagoon 525 006 33°00'58"N,117°16'52"W 322 San Gabriel River 524 005 33°45'12"N,118°06'15"W 304 San Miguel Island 501006 34°02'32"N,120°22'30"W 270 San Nicolas Island 524 011 33°14'30"N,119°30'30"W 312 San Pedro Rock 429 013 37°35'43"N,122°31'20"W 192 Sand Hill Cove 454 008 36°31'01"N,121°57'01"W 218 Santa Barbara Island 524 008 33°28'37"N,119°02'03"W 306 Santa Clara River 502 003 34°14'08"N,119°15'51"W 284 Santa Cruz Island 502 010 294 Santa Cruz Island - Kinton Pt. to Diablo Pt. 502 014 34°0'30"N,119''53'Wto 34°3'N,119°45'W 296 Santa Margarita River 525 003 33°13'57"N,117''24'37"W 320 "Santa Maria River" 501001 34°58'09"N,120°38'51"W 262 Santa Rosa Island, Sandy Pt. to Carrington Pt. 501007 270 Saunders Landing 404 020 38°51'13"N,123°30'05"W 158 369 Appendix C (Continued) Name Schoolhouse Creek to Albion River Scorpion Rock Scotty Point to Megwill Point "Sea Gull Rock" "Sea Lion Rock" Sea Lion Rock Sea Lion Rocks Sea Ranch Seal Cove to Lost Point Seal Rocks Seal Rock Cliffs "Section 30 Cove" Shag Rock "SheU Beach Rocks" Shell Wright Beach Rocks Sister Rocks Sisters, The Smith and Whaler Islands "Snag Rock" "Soberanes Creek Rocks" "Soberanes Point South" Soldier Frank Point "Sonoma-Marin County Line" South San Diego Bay "SpUt Rock" Sponner's Cove "Sppit Rock" Square Black Rock Steamboat Rock Stewarts Point to Rocky Point "Strawberry Cove" Sugarloaf Island Sutil Island Sweetwater River "Tepona Rock" Terminal Island Three Brothers & Hair Seal Rocks Tijuana River Mouth Tolowa Rocks Tomales Point "Torre Canyon Rocks" Trinidad Bay Rocks Trinidad Head Triplett Gulch "Unmapped Island" Unnamed Point Unnamed Rock Unnamed Rocks Unnamed Small Rocks Usal Bay Van Damme Cove Venice Beach Wedding Rock Westport "Whaler Island" Wharf Rocks Colony 379 028 502 010 325 053 325 017 325 018 325 043 404 001 404 025 524 013 429 009 429 032 404 019 524 007 477 035 404 036 325 009 429 041 477 033 325 054 454 026 454 027 379 016 404 040 545 005 325 054 477 027 502 013 454 019 325 042 404 027 379 020 325 041 524 009 545 008 325 054 524 003 325 055 545 006 325 007 404 011 454 013 325 054 325 025 404 021 477 019 477 015 477 004 477 010 325 046 379 015 379 027 524 002 325 016 379 018 325 045 379 008 Lat., Long. 39°15'N,123°46'30"W 34°02'50"N,119°32'47"W 41°05'N,124°09'W 41°05'2r'N,124°09'07"W 41°05'40"N,124°09'49"W 40°19'35"N,124°21'38"W 38°55'07"N,123°43'45"W 38°42'N,123°27'30"W 32°52'N,118P31'Wto 32°54'10"N,118^32'20"W 37°46'42"N,122''30'53"W 37°23'N,122°25'W 38°52'39"N,123°40'10"W 33°29'15"N,119^02'05"W 35°09'06"N,120''40'11"W 38°25'N,123°06'W 41°39'29"N,124''08'47"W 37°59'22"N,122°26'25"W 35°09'00"N,120°45'15"W 41°03'N,124°08'W 36°27'18"N,121°55'35"W 36°26'47"N,121''55'35"W 39°45'18"N,123''50'15"W 38° 1 7'20"N,123'' 00'20"W 32°36'N,117°07'W 41°03'N,124''08'W 35°16'21"N,120°53'57"W 34°02'45"N,1 19°43'30"W 36°04'21"N,121°36'35"W 40°24'54"N,124°24'09"W 38°39'N,123°38'45"W 39°35'37"N,123°47'10"W 40°26'18"N,124°24'41"W 33P28'50"N,119°02'50"W 32°38'30"N,117°06'35"W 41°03'N,124°08'W 33°57'30"N,118°27'30"W 40°19'40"N,124°21'58"W 32°33'25"N,117°07'48"W 41°45'15"N,124°14'W 38°12'13"N,122'=57'39"W 36°11'25"N,121°42'46"W 41°03N,124°08'W 41°03'09"N,124°08'58"W 38°49'N,123°36'15"W 35°48'20"N,121°22'26"W 35°57'00"N,121°28'51"W 35°S3'05"N,121°27'46"W 35'*14'40"N,120''53'39"W 41°42'N,124°08'W 39°48'45"N,123°50'30"W 39°16'10"N,123°4r28"W 33°57'30"N,1 18°27'30"W 41°08'28",124°09'32"W 39° 38'00"N,1 23°47' 1 0"W 41°45'N,124°13'W 39°07'49"N,123°43'24"W Page 134 290 98 74 76 92 144 162 316 186 204 156 306 258 172 68 210 256 100 228 230 122 178 334 100 252 294 224 90 164 126 90 308 336 100 302 102 336 66 154 222 100 82 158 248 246 240 244 92 122 132 302 74 124 92 116 370 Appendix C (Continued) Name Colony Lat., Long. Page White Rock 325 008 41°44'46"N,124°13'44"W 60 White Rock 325 012 41°30'56"N,124°05'06"W 70 White Rock 325 019 41°05'13N,124°09'33"W 76 White Rock 379 010 39°05'42"N,123°43'U"W 116 Wilson Rock 325 058 41°35'45"N,124°06'37"W 104 Yankee Point 454 024 36°29'29"N,121° 56'41"W 228 Verba Buena Island 429 038 37°48'34"N,122°22'15"W 208 "333 Point" 379 032 39°05'N,123°42'30"W 140 "3 Rocks" 477 023 35°45'06"N,121°19'07"W 250 "36 North" 477 013 35°58'36"N,121°29'15"'W 246 371 I .s. KtSHAWILOIJFK- SKHVK-K DEPARTMENT OF THE INTERIOR U.S. FISH AND WILDLIFE SERVICE As the Nation's principal consen/ation agency, the Department of the Interior has respon- sibility for most of our nationally owned public lands and natural resources. This Includes fostering the wisest use of our land and water resources, protecting our fish and wildlife, preserving th».environmental and cultural values of our national parks and historical places, and providing for the enjoyment of life through outdoor recreation. The Department as- sesses our energy and mineral resources and works to assure that their development is in the best 'interests of all our people. The Department also has a major responsibility for American Indian reservation communities and for people who live in island territories under U.S. administration.