Analyses/Maps

Biogeography of Marine Birds

Quick link to a PDF of the marine bird chapter, Phase II

Links to other PDF maps and descriptions for marine birds are below.

Marine Bird Density off North/Central California by ocean season and for all seasons. (1980-2001; number of species =76)

Marine Bird Colonies along long north/central California (mostly 1989-2006; number of breeding species mapped= 16)

The California Current system runs south through the central California study area; it is one of the most productive ocean systems in the world (Glantz and Thompson 1981). Hence, the study area contains a rich fauna of marine birds, as evidenced in species abundance and richness. In addition to a populous breeding community, the community of seasonal residents and migrants is even more robust, as central California is the destination for many marine bird species seeking productive feeding areas and acceptable habitat in which to spend their non-breeding periods. Unlike many marine organisms, marine birds have a tremendous mobility and the fact that many seek this region to find food bespeaks well of the region's trophic richness. Fortunately, for the purpose of management of the central California National Marine Sanctuaries, the marine avifauna of the study area have been one of the most thoroughly surveyed.

The objectives of this assessment were to: 1) identify spatial and temporal distributions and patterns for marine birds that occur in ocean waters off north/central California between Point Arena (38.91°N) and Pt Sal (34.90°N); 2) identify important finer-scale areas and time periods associated with higher concentrations of these species; and 3) identify important data and information gaps observed as a result of this analysis. In this analysis, "important" season or area refers to those having relatively higher concentrations of a particular species. The products linked and described below address these project objectives.

Table 3.1 below is a list of the marine bird species included in the assessment, with links to PDF versions of maps and descriptions in the mammal chapter. Also below is Table 3.6, which identifies important at-sea areas by ocean season for marine birds, based on analyses of density, biomass and diversity off north/central California (using CDAS data, 1980-2001). Table 3.7 (linked below) lists the top 50 marine bird colonies along the north/central California coast. Table 3.5 (linked below) is a summary of temporal and spatial associations of selected marine birds at sea off north/central California, based on CDAS (1980-2001).

Links to all bird chapter tables (3.1-3.11) follow, with summary information on the survey data used, population status, life history and management information and spatial and temporal patterns observed. Over 200 maps were developed for the marine bird chapter (including several maps in the Appendix with a more pelagic/offshore focus; GIS files for most of the maps will be available at: http://ccma.nos.noaa.gov/products/biogeography/canms_cd/htm/data.htm

Selected Summary Findings from the Marine Bird Assessment:

• Based on the available data, the boundaries of the national marine sanctuaries off north/central California generally encompass the areas of high concentrations and diversity for marine birds in the study area, except for: 1) the western edge of the Gulf of Farallones area; 2) the "sanctuary exclusion area", off San Francisco and 3) Pacifica, which is excluded from the Monterey Bay National Marine Sanctuary.
• In general, the marine birds offnorth/central California are dominated in number and biomass by seasonally resident, nonbreeding species, such as sooty shearwater, pink-footed shearwater, northern fulmar and black-legged kittiwake. The richness of the food web is the primary factor that attracts these species to the region.
• Seasonal, interannual and decadal variation of the regional biogeography of marine birds is influenced by the vagaries of marine climate, which is driven by the California Current System, local upwelling centers and global climate. Therefore, the biogeographic patterns of marine birds are not static and exhibit a dramatic spatial and temporal variation, both in species composition and species abundance.
• The Gulf of the Farallones, the area lying inside a triangle defined by Pt. Reyes, the Farallon Islands and Año Nuevo Island, is the most important area for marine birds in California. The reasons are: 1) large, taxonomically diverse and demographically-related populations breed at the three aforementioned sites; and 2) a relatively high diversity of habitat (e.g., San Francisco Bay tidal plume, a shallow sandy shelf, rocky reefs, submarine peaks, and the upper continental slope) attracts a variety of migrant and seasonally resident species.
• A "halo" of individuals was apparent around important breeding sites such as the Farallon Islands and Año Nuevo Island. This pattern is the result of breeding individuals searching for food, but going only as far as necessary to provide for their young. The Farallon "halo" for ashy storm-petrel, western gull, common murre, rhinoceros auklet and Cassin's auklet extends substantially west of the Gulf of the Farallones National Marine Sanctuary.
• The marine birds of the Gulf of the Farallones/Cordell Bank NMS (as defined above) and the birds of the Monterey Bay NMS are associated with different habitat features. The Gulf of the Farallones has islands and a relatively broad shelf, while Monterey Bay has a relatively narrow but sheltered shelf, cut by an immense, deep submarine canyon. The greater oceanic influence and lack of breeding islands in the Monterey Bay NMS drive the marine bird species group there.

Major Section Contributors, Reviewers and References

Major contributors to the marine bird assessment included David Ainley, Larry Spear, Janet Casey, R. Glenn Ford, Tracy Gill, Ken Buja, Gerry McChesney, Wendy Williams, Lisa Ballance, and Carol Keiper. See the bird chapter for a complete listing of contributors, reviewers, personal communications and references.

List and Links to PDF bird maps, tables and descriptions

Table 3.1 (modified for web): Marine bird species and links to maps and descriptions in the Phase II assessment off north/central California

Common Name	Scientific Name	Order/Family/SubFamily	Total No. of Maps per Species or Species Group	PDF Map Description	PDF Maps
Species mapped separately & used in summary diversity & density analyses (n=31; 124 maps)
Pacific Loon	Gavia pacifica	Gaviiformes/Gaviiadae	4	Description	Maps 1-4
Laysan Albatross	Phoebastria immutabilis	Procellariiformes/Diomedeidae	8	Description	Maps 1-4 Maps 4-8
Black-footed Albatross	Phoebastria nigripes	Procellariiformes/Diomedeidae	8	Description	Maps 1-4 Maps 4-8
Northern Fulmar	Fulmarus glacialis	Procellariiformes/Procellariidae	8	Description	Maps 1-4 Maps 4-8
Pink-footed Shearwater	Puffinus creatopus	Procellariiformes/Procellariidae	4	Description	Maps 1-4
Buller's Shearwater	Puffinus bulleri	Procellariiformes/Procellariidae	8	Description	Maps 1-4 Maps 4-8
Sooty Shearwater	Puffinus griseus	Procellariiformes/Procellariidae	8	Description	Maps 1-4 Maps 4-8
Black-vented Shearwater	Puffinus opisthomelas	Procellariiformes/Procellariidae	4	Description	Maps 1-4
Fork-tailed Storm-Petrel	Oceanodroma furcata	Procellariiformes/Hydrobatidae	8	Description	Maps 1-4 Maps 4-8
Leach's Storm-Petrel	Oceanodroma leucorhoa	Procellariiformes/Hydrobatidae	8	Description	Maps 1-4 Maps 4-8
Ashy Storm-Petrel	Oceanodroma homochroa	Procellariiformes/Hydrobatidae	8	Description	Maps 1-4 Maps 4-8
Black Storm-Petrel	Oceanodroma melania	Procellariiformes/Hydrobatidae	8	Description	Maps 1-4 Maps 4-8
California Brown Pelican	Pelecanus occidentalis californicus	Pelecaniformes/Pelecanidae	4	Description	Maps 1-4
Brandt's Cormorant	Phalacrocorax penicillatus	Pelecaniformes/Phalacrocoracidae	4	Description	Maps 1-4
Double-crested Cormorant	Phalacrocorax auritus	Pelecaniformes/Phalacrocoracidae	4	Description	Maps 1-4
Pelagic Cormorant	Phalacrocorax pelagicus	Pelecaniformes/Phalacrocoracidae	4	Description	Maps 1-4
Red-necked Phalarope	Phalaropus lobatus	Charadriiformes/Scolopacidae	4	Description	Maps 1-4
Red Phalarope	Phalaropus fulicarius	Charadriiformes/Scolopacidae	8	Description	Maps 1-4
Heermann's Gull	Larus heermanni	Charadriiformes/Laridae/Larinae	4	Description	Maps 1-4
Western Gull	Larus occidentalis	Charadriiformes/Laridae/Larinae	4	Description	Maps 1-4
Glaucous-winged Gull	Larus glaucescens	Charadriiformes/Laridae/Larinae	4	Description	Maps 1-4
Sabine's Gull	Xema sabini	Charadriiformes/Laridae/Larinae	4	Description	Maps 1-4
California Gull	Larus californicus	Charadriiformes/Laridae/Larinae	4	Description	Maps 1-4
Black-legged Kittiwake	Rissa tridactyla	Charadriiformes/Laridae/Larinae	4	Description	Maps 1-4
Arctic Tern	Sterna paradisaea	Charadriiformes/Laridae/Sterninae	4	Description	Maps 1-4
Common Murre	Uria aalge	Charadriiformes/Alcidae	4	Description	Maps 1-4
Pigeon Guillemot	Cepphus columba	Charadriiformes/Alcidae	4	Description	Maps 1-4
Cassin's Auklet	Ptychoramphus aleuticus	Charadriiformes/Alcidae	4	Description	Maps 1-4
Rhinoceros Auklet	Cerorhinca monocerata	Charadriiformes/Alcidae	4	Description	Maps 1-4
Tufted Puffin	Fratercula cirrhata	Charadriiformes/Alcidae	4	Description	Maps 1-4
Marbled Murrelet	Brachyramphus marmoratus	Charadriiformes/Alcidae	4	Description	Maps 1-4
Species mapped together & used in diversity & density analyses (n=9 , 16 maps)
Western Grebe	Aechmophorus occidentalis	Podicipediformes/Podicipedidae	4; Mapped with Clark's Grebe	Description	Maps 1-4
Clark's Grebe	Aechmophorus clarkii	Podicipediformes/Podicipedidae	Mapped with Western Grebe	Description	Maps 1-4
Black Scoter	Melanitta nigra	Anseriformes/Anatidae	4; Mapped with other scoters	Description	Maps 1-4
Surf Scoter	Melanitta perspicillata	Anseriformes/Anatidae	Mapped with other scoters	Description	Maps 1-4
White-winged Scoter	Melanitta fusca	Anseriformes/Anatidae	Mapped with other scoters	Description	Maps 1-4
Caspian Tern	Sterna caspia	Charadriiformes/Laridae/Sterninae	4; Mapped with Elegant Tern	Description	Maps 1-4
Elegant Tern	Sterna elegans	Charadriiformes/Laridae/Sterninae	Mapped with Caspian Tern	Description	Maps 1-4
Xantus's Murrelet	Synthliboramphus hypoleucus	Charadriiformes/Alcidae	4; Mapped with Craveri's Murrelet	Description	Maps 1-4
Craveri's Murrelet	Synthliboramphus craveri	Charadriiformes/Alcidae	Mapped with Xantus's Murrelet	Description	Maps 1-4

Table 3.1a Community Metric /Theme maps across the marine bird species (76 species)

Map Name	Total No. of Maps per Species or Species Group	PDF Map Description	PDF Maps
Marine bird density, by season and for all seasons.	4	Description	Maps 1-4
Marine bird biomass, by season and for all seasons.	4	Description	Maps 1-4
Marine bird diversity, by season and for all seasons.	4	Description	Maps 1-4
Major marine bird breeding colonies along the coast of north/central California	1	Description	Map 1
Marine bird densities in warm, cold, and neutral periods: 1980-2001	4	Description	Maps 1-4
Marine bird biomass in warm, cold, and neutral periods: 1980-2001	4	Description	Maps 1-4
Marine bird diversity in warm, cold, and neutral periods: 1980-2001	4	Description	Maps 1-4
Comparing densities of two “warmer water” marine bird species during El Niño and La Niña events: 1997-2000	4	Description	Maps 1-4
Comparing densities of two “cooler water” marine bird species during El Niño and La Niña events: 1997-2000	4	Description	Maps 1-4

Table 3.1b CDAS Survey Effort Maps for Marine Bird Analyses

Map Name	Total No. of Maps per Species or Species Group	PDF Map Description	PDF Maps
Spatial extent of ship-board surveys in the CDAS central California data set (1980-2001) used in the marine bird analysis.	4	Description	Maps 1-4
Spatial extent of aerial at-sea surveys in the CDAS central California data set (1980-2001) used in the marine bird analysis.	4	Description	Maps 1-4
Total at-sea survey effort (shipboard and aerial) used for the marine bird analysis, CDAS data (1980-2001)	4	Description	Maps 1-4

Table 3.1c Species in the CDAS data set used only in the diversity & density analyses and maps (n=37)

Common Name	Scientific Name	Order/Family/SubFamily
Red-throated Loon	Gavia stellata	Gaviiformes/Gaviidae
Common Loon	Gavia immer	Gaviiformes/Gaviidae
Horned Grebe	Podiceps auritus	Podicipediformes/Podicipedidae
Red-necked Grebe	Podiceps grisegena	Podicipediformes/Podicipedidae
Eared Grebe	Podiceps nigricollis	Podicipediformes/Podicipedidae
Murphy's Petrel	Pterodroma ultima	Procellariiformes/Procellariidae
Cook's Petrel	Pterodroma cookii	Procellariiformes/Procellariidae
Parkinson's Petrel	Procellaria parkinsoni	Procellariiformes/Procellariidae
Flesh-footed Shearwater	Puffinus carneipes	Procellariiformes/Procellariidae
Short-tailed Shearwater	Puffinus tenuirostris	Procellariiformes/Procellariidae
Manx Shearwater	Puffinus puffinus	Procellariiformes/Procellariidae
Townsend's Shearwater	Puffinus auricularis	Procellariiformes/Procellariidae
Wilson's Storm-Petrel	Oceanites oceanicus	Procellariiformes/Hydrobatidae
Wedge-rumped Storm-Petrel	Oceanodroma tethys	Procellariiformes/Hydrobatidae
Markham's Storm-Petrel	Oceanodroma markhami	Procellariiformes/Hydrobatidae
Least Storm-Petrel	Oceanodroma microsoma	Procellariiformes/Hydrobatidae
Red-billed Tropicbird	Phaethon aethereus	Pelecaniformes/Phaethonidae
Brown Booby	Sula leucogaster	Pelecaniformes/Phaethonidae
White Pelican	Pelecanus erythrorynchos	Pelecaniformes/Pelecanidae
South Polar Skua	Stercorarius maccormicki	Charadriiformes/Laridae/Stercorariinae
Pomarine Jaeger	Stercorarius pomarinus	Charadriiformes/Laridae/Stercorariinae
Parasitic Jaeger	Stercorarius parasiticus	Charadriiformes/Laridae/Stercorariinae
Long-tailed Jaeger	Stercorarius longicaudus	Charadriiformes/Laridae/Stercorariinae
Bonaparte's Gull	Larus philadelphia	Charadriiformes/Laridae/Larinae
Mew Gull	Larus canus	Charadriiformes/Laridae/Larinae
Ring-billed Gull	Larus delawarensis	Charadriiformes/Laridae/Larinae
California Gull	Larus californicus	Charadriiformes/Laridae/Larinae
Thayer's Gull	Larus thayeri	Charadriiformes/Laridae/Larinae
Glaucous Gull	Larus hyperboreus	Charadriiformes/Laridae/Larinae
Red-legged Kittiwake	Rissa brevirostris	Charadriiformes/Laridae/Larinae
Royal Tern	Sterna maxima	Charadriiformes/Laridae/Sterninae
Common Tern	Sterna hirundo	Charadriiformes/Laridae/Sterninae
Forster's Tern	Sterna forsteri	Charadriiformes/Laridae/Sterninae
Thick-billed Murre	Uria lomvia	Charadriiformes/Alcidae
Parakeet Auklet	Aethia psittacula	Charadriiformes/Alcidae
Ancient Murrelet	Synthliboramphus antiquus	Charadriiformes/Alcidae
Horned Puffin	Fratercula corniculata	Charadriiformes/Alcidae

Table 3.6. Important areas at sea for marine birds off north/central California.

	Biomass/Density			Diversity
Area	Davidson Current Season	Upwelling Season	Oceanic Season	Davidson Current Season	Upwelling Season	Oceanic Season
Cordell Bank	x	X
Farallon Escarpment (slope)	X	x	x	X	X	X
Farallon Ridge (includes Farallon Island area)	X	X	x
San Francisco Bay Tidal Plume		x	X	X
Pioneer Canyon				X	x	x
Año Nuevo Shelf	X		X
Ascension, Año & Cabrillo Canyons	X	x	x	X	x
Monterey Bay Inshore	X	x	X	X
Monterey Bay Canyon	X		x
Carmel Canyon				X
Point Sur Shelf			x
Point Sur Slope				X	x
Estero Bay & San Luis Obispo Bay	X		x

• Table 3.1. Marine bird species used in the Phase II analyses, organized by map treatment & family.
• Table 3.2. A summary of at-sea data sets in the CDAS Central California data set (1980-2001) used in the marine bird analyses.
• Table 3.3. Summary of combined data set effort by ocean season for the marine bird analysis.
• Table 3.4. Assignment of warm, cold and neutral periods, based on surface water temperature off Central California.
• Table 3.5. A summary of temporal and spatial associations of selected marine birds off north/central California.
• Table 3.6. Important areas at sea for marine birds off north/central California.
• Table 3.7. Top 50 marine bird colonies along the north/central California coast.
• Table 3.8. Top three independent variables (of 9 investigated) that explain the some of the variation in the densities at sea for 25 marine birds.
• Table 3.9. Effects of ocean season and ENSO (El Niño/ Southern Oscillation) events on the abundance of 26 species off central California from 1985 and 2002, as determined through multiple regression analyses.
• Table 3.10. A summary of changes in marine bird occurrence patterns, as a response to warm- and cold-ocean anomalies, as determined by visual comparison of species’ maps during the 1997-1998 El Niño event and the 1999-2000 La Niña event.
• Table 3.11. Life history and management information for selected marine birds along the north/central California coast.
• Appendix Table 1A: Summary of marine bird colonies along the coast of the north/central California Study Area and in San Francisco Bay (listed North to South)
• Appendix Table 1 B: Summary of related marine bird colony information along the coast of the north/central California Study Area and in San Francisco Bay (listed North to South)