Diet Overlap

Gavia immer (Great Northern Loon)
Larus argentatus (Herring Gull)

Common Diet

Gadus morhua (rock cod)

Common Habitat

Acadia National Park
Alaska Maritime National Wildlife Refuge
Alaska Peninsula montane taiga
Alberta Mountain forests
Alberta-British Columbia foothills forests
Aleutian Islands Biosphere Reserve
Aleutian Islands tundra
Algonquin Provincial Park
Alto Golfo de California y Delta del Rio Colorado
ANSE DU FIER D'ARS EN RE
Apostle Islands National Lakeshore
Archipel de Glénan
Arctic National Wildlife Refuge
Arkansas Post National Memorial
Atlantic mixed forests
Audubon National Wildlife Refuge
Baie de Saint-Brieuc - Est
Baie de Vilaine
Baltic mixed forests
Banff National Park
Beringia lowland tundra
Beringia upland tundra
Berwickshire and North Northumberland Coast
Bideford Bay Biosphere Reserve
Biscayne National Park
Blackbeard Island National Wildlife Refuge
Blackwater National Wildlife Refuge
Bombay Hook National Wildlife Refuge
British Columbia mainland coastal forests
Brooks-British Range tundra
Bruce Peninsula National Park
Cabo Busto-Luanco
Cabrillo National Monument
California Coast Ranges Biosphere Reserve
Canaveral National Seashore
Cape Breton Highlands National Park
Cape Cod National Seashore
Cape Hatteras National Seashore
Cape Lookout National Seashore
Cape Romain National Wildlife Refuge
Carmarthen Bay and Estuaries/ Bae Caerfyrddin ac Aberoedd
Carolinian-South Atlantic Biosphere Reserve
Cascade Mountains leeward forests
Cedar Creek LTER Site
Celtic broadleaf forests
Central British Columbia Mountain forests
Central Canadian Shield forests
Central Gulf Coastal Plain Biosphere Reserve
Central Pacific coastal forests
Champlain-Adirondack Biosphere Reserve
Channel Islands National Marine Sanctuary
Channel Islands National Park
Chattahoochee River National Recreation Area
Colonial National Historic Park
Cook Inlet taiga
Copper Plateau taiga
Crosswinds Marsh
Cumberland Island National Seashore
Curecanti National Recreation Area
Davis Highlands tundra
De Soto National Wildlife Refuge
Dee Estuary/ Aber Dyfrdwy
Denali Biosphere Reserve
Dornoch Firth and Morrich More
Eastern Canadian forests
Eastern Canadian Shield taiga
Eastern Great Lakes lowland forests
Effigy Mounds National Monument
Elk Island National Park
Elkhorn Slough Preserve
Embalses del centro (San Andrés,la Granda, Trasona y la Furta)
English Lowlands beech forests
Essex Estuaries
Estuaire de la Loire - Baie de Bourgneuf
Farallon National Wildlife Refuge
Faroe Islands boreal grasslands
Fathom Five National Marine Park
Felsenthal National Wildlife Refuge
Fire Island National Seashore
Firth of Tay & Eden Estuary
Florida Keys National Marine Sanctuary
Forillon National Park
Fort Caroline National Memorial
Fort Matanzas National Monument
Fort Pulaski National Monument
Fraser Plateau and Basin complex
Fundy National Park
Gates of the Arctic National Park
Gateway National Recreation Area
George Washington Birthplace National Monument
Georgian Bay Islands National Park
Glacier Bay National Park and Preserve
Glen Canyon National Recreation Area
Golden Gate National Recreation Area
Grand Canyon National Park
Grand Portage National Monument
Great Smoky Mountains National Park
Great Swamp National Wildlife Refuge
Greenwater Provincial Park
Gros Morne National Park
Gwaii Haanas National Park Reserve
Hot Springs National Park
Iceland boreal birch forests and alpine tundra
Indiana Dunes National Lakeshore
Inner Galway Bay SPA
Interior Alaska-Yukon lowland taiga
Interior Yukon-Alaska alpine tundra
Isle of Rum National Nature Reserve
Isle Royale Biosphere Reserve
Ivvavik National Park
Jean Lafitte National Hist. Park & Preserve
Kejimkujik Seaside Adjunct
Kluane National Park and Reserve
Kouchibouguac National Park
La Mauricie National Park
Lac du Der
Lacs de la forêt d'Orient
Lago di Mezzola e Pian di Spagna
Lake Mead National Recreation Area
Lake Meredith National Recreation Area
Lake Roosevelt National Recreation Area
Lake Superior Provincial Park
Land Between the Lakes Biosphere Reserve
Lava Beds National Monument
Little St. Simons Island
LITTORAL SEINO-MARIN
Low Arctic tundra
Marais du Mès, baie et dunes de Pont-Mahé, étang du Pont de Fer, île Dumet
MARAIS POITEVIN
Marais salants de Guérande, traicts du Croisic, dunes de Pen Bron
MARISMAS DEL ODIEL
Mid-Clare Coast SPA
Mid-Continental Canadian forests
Middle Arctic tundra
Midwestern Canadian Shield forests
Mingan Archipelago National Park Reserve
Mor Braz
Moray Firth
Morristown National Historical Park
Muskwa-Slave Lake forests
Nahanni National Park Reserve
New England-Acadian forests
Newfoundland Highland forests
Nez Perce National Historical Park
Niagara Escarpment Biosphere Reserve
Noatak Biosphere Reserve
North America
North Atlantic moist mixed forests
North Bull Island
North Central Rockies forests
North Norfolk Coast
Northeastern coastal forests
Northern Canadian Shield taiga
Northern Cordillera forests
Northwest Russian-Novaya Zemlya tundra
Northwest Territories taiga
Ogilvie-MacKenzie alpine tundra
Okefenokee National Wildlife Refuge
Olympic Biosphere Reserve
Organ Pipe Cactus Biosphere Reserve
Ouessant-Molène
Pacific Rim National Park Reserve
Padre Island National Seashore
Penarronda-Barayo
PERTUIS CHARENTAIS - ROCHEBONNE
Pictured Rocks National Lakeshore
Point Pelee National Park
Point Reyes National Seashore
Polar Bear Provincial Park
Prince Albert National Park
Prince Edward Island National Park
Puget lowland forests
Pukaskwa National Park
Queen Charlotte Islands
Redberry Lake Biosphere Reserve
Redwood National Park
Reserva de la Biosfera de Urdaibai
Reserva de la Biosfera El Vizcaino
Reserve de la Biosphere d'Iroise
Reserve de la Biosphere de Charlevoix
Reserve Nationale de Camargue Biosphere Reserve
Ría de Ribadesella-Ría de Tinamayor
Ría de Villaviciosa
Ría del Eo
Riding Mountain Biosphere Reserve
Rocky Mountain Biosphere Reserve
Rondeau Provincial Park
Roosevelt Vanderbilt National Historic Site
Saguenay - St. Lawrence Marine Park
Saint Croix International Historic Site
Saint Lawrence Islands National Park
Salt Plains National Wildlife Refuge
Santa Cruz Island Preserve
Santa Monica Mountains National Recreation Area
Saratoga National Historical Park
Scandinavian coastal conifer forests
Scandinavian Montane Birch forest and grasslands
Secteur marin de l'île d'Yeu jusqu'au continent
Sefton Coast
Severn Estuary/ Môr Hafren
Sevilleta LTER Site
Sikhote-Alinskiy Biosphere Reserve
Sleeping Bear Dunes National Lakeshore
South Atlantic Coastal Plain Biosphere Reserve
South Avalon-Burin oceanic barrens
Southern Appalachian Biosphere Reserve
Southern Great Lakes forests
Southern Hudson Bay taiga
Spreewald
St. Kilda National Nature Reserve
Tawas Point State Park
Tennessee River Gorge
Terra Nova National Park
Tuktut Nogait National Park
Ukkusiksalik National Park
Upper Midwest forest-savanna transition
Upper Miss. River Nat'l Wildlife Refuge
Urdaibaiko Itsasadarra / Ría de Urdaibai
Valley Forge National Historical Park
Virginia Coast Biosphere Reserve
Voyageurs National Park
Wapusk National Park
Waterton Biosphere Reserve
Western Great Lakes forests
Western Michigan University’s Asylum Lake
Wheeler National Wildlife Refuge
Whiskey-Shasta-Trinity National Recreation Area
Winisk River Provincial Park
Wood Buffalo National Park
Woodland Caribou Provincial Wilderness Park
Wrangell-St. Elias National Park and Preserve
Yellowstone Biosphere Reserve
Yoho National Park
Yukon Interior dry forests

Attributes / relations provided by
♦ 1del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona.
♦ 2Diets of adult and chick Herring Gulls Larus argentatus argenteus on Ailsa Craig, south-west Scotland., M. Nogales, B. Zonfrillo and P. Monaghan, SEABIRD 17: 56-63