Willets (Tringa semipalmata ) are among the largest species of sandpipers. Western willets, like those shown in this week's photo, breed in freshwater prairie marshes in western North America, and winter on both coasts. Nesting on the ground, usually in well-hidden locations in short grass, often in colonies, willets forage on mudflats or in shallow water. Their primary food is insects, crustaceans, and marine worms. They use their long, straight beaks to probe in sand or mud for food.
Willets compete directly for food with a number of other similarly-sized shorebirds, often interacting aggressively for food and space. Common competitive species include long-billed curlews (Numenius americanus), least sandpipers (Calidris minutilla ), common terns (Sterna hirundo ), least terns (Sterna antillarum ), Wilson's phalaropes (Phalaropus tricolor), greater yellowlegs (Tringa melanoleuca ), killdeer (Charadrius vociferus ), dowitchers (Limnodromus), Wilson's plovers (Charadrius wilsonia), marbled godwits (Limosa fedoa), and gulls (Larus sp.). They are also know to compete with American crows (Corvus brachyrhycnhos) and fish crows (Corvus osifragus).
This week's photo was taken with a Canon EOS 10D dSLR and an EF 100 - 400 mm lens zoomed to 350 mm. Exposure was for 1/500 sec at f/8.0 and ISO 100.
Willets eat a wide variety of invertebrate prey, depending on local abundance and habitat. They eat insects, crustaceans, molluscs, polychaete worms, and occasional fish. Willets feed at all times of the day, also depending on local abundance of prey, tide patterns, and moonlight. They use several foraging strategies: chasing prey down visually and using their bills to probe for prey in substrates or turn over objects to find prey underneath. They may also walk through shallow water with their bills open and held in the water to hunt by touch for prey or swim on the water and pluck prey from the surface. They may defend foraging territories in their wintering range, or they may abandon territories and forage with others in areas of abundant prey.)