Appendix C Foraging Guilds Bird Forage Guilds Forage Common Name Food Habits General Comments Guild American Wigeon Vegetation, snails, beetles, crickets. Dominantly vegetarian (eg. eelgrass and algae) Eurasian Wigeon Vegetation, eelgrass Gadwall Leaves, stems and tubers of aquatic plants. Eats some small fishes and aquatic invertebrates Green-winged Teal Feeds on seeds and aquatic invertebrates (eg. Mollusks, aquatic insects, seeds) Primarily eat vegetation - Blue-winged Teal Vegetative parts of aquatic plants as well as seeds. Also consumes aquatic invertebrates. Sometimes eat small fishes Mallard Eats seeds, rootlets and tubers of aquatic plants, insects, mollusks, amphibians, small fishes (mostly vegetation). and aquatic invertebrates Northern Pintail Mostly vegetation. Feed on seeds and nutlets of aquatic plants, amphipods and other invertebrates. American Coot Submergent vegetation in open water. Leaves, seeds and roots of aquatic plants. Some animal food. Hooded Merganser Small fishes, crayfishes and other crustaceans obtained by diving underwater. Northern Shoveler Seeds of sedges, bulrushes, sawgrass, etc. Also eats mollusks, aquatic insects and crustaceans. Bufflehead Eats aquatic insects, crustaceans, mollusks, crustaceans, snails, amphipods, small fishes and some aquatic plants. Surf Scoter Mainly invertebrates, mollusks, crustaceans and aquatic insects with some aquatic plants in summer. Barrow's Goldeneye Mollusks (especially blue mussels), some seastars, and marine worms. Dives for mussels and invertebrates . Black Scoter Mollusks comprise a majority of the diet; the blue mussel. Also eats crustaceans, some fishes and plant foods. Eat mostly aquatic insects, Common Goldeneye Aquatic insects, crustaceans and aquatic plants. crustaceans, animal food. Common Merganser Eats mainly fishes, also amphibians, crustaceans, mollusks and other invertebrates. Sometimes eat aquatic Greater Scaup Mollusks and in some areas eats seeds leaves, stems of plants. vegetation but minimal Diving Ducks Diving Harlequin Duck Mostly benthic aquatic invertebrates, mostly crustaceans and mollusks, also insects and a few small fishes. Long-tailed Duck Crustaceans, fishes and their eggs, mollusks, and aquatic insects. Aquatic plants (roots, leaves, buds, seeds). Mysis spp., Onisimus spp., and biva White Winged Scouter Mostly animal food, eats mollusks, crustaceans, aquatic insects and fishes. Killdeer Small invertebrates. Pacific Golden-Plover Primarily feeds on insects. Also eats some small mollusks and crustaceans. Black-bellied Plover Marine worms, insects, mollusks, crustaceans. Black Oystercatcher Mollusks, probes sand for marine worms. Semipalmated Plover Marine worms, small mollusks and crustaceans, insects eggs and larvae. Dunlin Larvae of flies and mosquitoes, crustaceans, marine worms, mollusks, and insects. Red Knot Mainly mollusks, eggs of crabs and horseshoe crab, insects, some seeds and small fishes. Marbled Godwit Mollusks, crustaceans, worms, insects. Feed mostly on invertebrates, Red Phalarope Insects, crustaceans, larval fishes and small jelly fishes. mollusks, crustaceans, fishes, ShorebirdsGreater Yellowlegs Small fishes, Ducks Dabbling insects and their larvae, snails, crabs, worms and tadpoles. worms Long-billed Dowitcher Insects and their larvae, mollusks, crustaceans, marine worms, spiders and seeds of aquatic plants. Spotted Sandpiper Small invertebrates. Western Sandpiper Aquatic insects, also eats mollusks, worms, crustaceans and algae. Least Sandpiper Small insects, crustaceans, mollusks, and worms. Wilson's Phalarope Insects, mosquitoes and crane flies. On salt flats may feed on alkali flies, brine shrimp, seeds of aquatic plants. Rock Sandpiper Crustaceans, small mollusks, insects and worms. Black Turnstone Slugs, mollusks, and crustaceans. Seaweeds for small marine animals, may also eat berries but primarily aquatic invertebrates. Common Snipe Earthworms, insect larvae, small crustaceans, and molluscs. Plant fibers and grit are also consumed. Bird Forage Guilds Forage Common Name Food Habits General Comments Guild Bonaparte's Gull Primarily insects and fishes, also crustaceans and marine worms and scavenges. California Gull Insects, mice. Glaucous-winged Gull Fishes, mollusks, crustaceans, garbage and carrion. Herring Gull Various animals and garbage. Fishes, mollusks, crustaceans Mew Gull Fishes, Crustaceans and mollusks, scavenges in harbours. Gulls and garbage Ring-billed Gull Animals and plant material and garbage. Western Gull Fish crustaceans, mollusks, worms, garbage. Thayer's Gull Fishes, mollusks, crustaceans, marine worms, carrion and garbage. Ross's Gull Beetles, gnats and other insects. Common Loon Piscivorous - any prey they can see, yellow perch, flounder, rock cod, minnows, crustaceans… Horned Grebe Invertivore, Piscivore - mainly small fishes, crustaceans and aquatic insects; also amphibians and leeches. Red-breasted Merganser Invertivore, Piscivore -mostly fishes plus some crustaceans. Insects important to young. Common Murre Mostly fish diet. Eat mainly fishes; some also Pelagic Cormorant Feeds on fishes; also consumes crabs, shrimps, marine worms, and amphipods. eat crustaceans, aquatic Brandt's Cormorant Feeds on small fishes and squid; also feeds on crabs and shrimps. insects, mollusks Pigeon Guillemot Mainly on small fishes; also includes mollusks, crustaceans, and marine worms. Red-necked Grebe Mainly on small fishes; also eats aquatic and land insects, crustaceans, mollusks, aquatic worms, tadpoles. Red-throated Loon Mainly fishes; also eats shrimps, snails, aquatic insects and some aquatic plants. Piscivorous Diving Birds Pied-billed Grebe Eats mainly fishes, crustaceans, insects; also amphibians, other invertebrates. Brant Goose Mainly eelgrass, saltmarsh grass, sea lettuce; also forage on grains in fields. Primarily eat marsh Canada Goose Marsh grasses, sprouts of winter wheat, clover, cattails, bulrushes, algae; also eats mollusks and small crustaceans. vegetation; eat grains during Snow Goose Eats grains; uproots sedges, marsh grasses, and aquatic plants (eats stem, rhizomes, roots, bulbs). Swans Geese/ Geese/ food shortage Trumpeter Swan Aquatic vegetation. Young eat aquatic insects and crustaceans and in 5 weeks feed on aquatic plants. Some grazing. DABBLING DUCKS American Wigeon (Anas americana) • Feeds on leaves, stems, buds, and some seeds of pondweeds, wigeon grass, grasses, and sedges. Forges in shallow water and grazes in fields. May also some snails, beetles, and crickets (Terres, 1980). • Study in Boundary Bay - Zostera japonica comprises a large single percentage of the diet. Leaves most important to widgeon (Baldwin & Lovvorn, 1994). • Wigeon are almost exclusively vegetarian. On estuaries, wigeon consume aquatic plans such as eelgrass (Zostera spp.) and algae (Entraomorpha sp.). Over the years, changes in availability of items may have lead to changes in wigeon feeding habits. Inland pasture is now more important that either mudflats or salt marshes for European Wigeon in Britian. In the Fraser delta it appears that the agricultural areas provide a greater feeding opportunity for wigeon between October and January, than do the marshes (Duynstee, 1992). Eurasian Wigeon (Anas penelope) • Feed on intertidal Zostera beds in Northern Europe (Fox, 1996). • Prefer open feeding sites, such as agricultural areas and hayfields. Graze on P. trivialis leaf tips. (Jacobsen, 1992). • Wigeon are almost exclusively vegetarian. On estuaries, wigeon consume aquatic plants such as eelgrass (Zostera spp.) and algae (Enteromorpha sp.). Over the years, changes in availability of these marsh plants may have lead to changes in wigeon feeding habits. Inland pasture in now more important that either mudflats or saltmarshes for European Wigeon in Britian. In the Fraser delta it appears that the agricultural areas provide a greater feeding opportunity for wigeon between October and January, than do the marshes (Duynstee, 1992). Gadwall (Anas strepera) • Feeds on leaves, stems, and tubers of aquatic plants. Also eats algae and seeds of sedges and grasses. Occasionally grazes in pastures and grain fields; may feed on acorns. Eats some small fishes and aquatic invertebrates (e.g., insects, crustaceans). Aquatic invertebrates comprise about half the diet in spring and summer; eats green portions of aquatic plants in non-nesting season; feeds generally in water 15-66 cm deep (Ringelman 1990). Juveniles initially eat equal amount of animal and plant food; plant food begins to dominate after 2 weeks (Ringelman, 1990). • They are considered herbivorous, except during spring when some aquatic invertebrates are consumed. Gadwall was documented to consume the following invertebrates: insects (caddis flies, beetles, true flies, midges), crustaceans (fairy shrimps, water fleas). • Spring and Summer – filamentous algae, widgeongrass, musckgrass, sago pondweed, elodea, fairy shrimp, seed shrimp, water fleas, midges, beetle larvae. Fall and Winter – Filamentous algae, dwarf spikerush, widgeongrass, spiked watermilfoil, baby pondweed, seed shrimp, fragrant flatsedge, redroot sedge. Green-winged Teal (Anas crecca) • Eats aquatic plants; seeds of sedges, smartweeds, pondweeds, and grasses; aquatic insects, mollusks, crustaceans and tadpoles. In fall waste grain. Also eats berries, grapes, acorns. Dabbles in shallow water, also forages on land. • Study in Boundary Bay – Amphipods, primarily Corophium insidiosum were the greatest fraction of the green-winged teal diet. (Baldwin and Lovvorn, 1994). • Green-winged