American Avocet

Common Name: American Avocet

Scientific Name: Recurvirostra americana

Appearance: The American Avocet is a large, graceful shorebird measuring about 18 inches long (45 cm), and weighing about 11 ounces (315 g). American Avocets have white underparts, a black and white striped back, and black wings with white patches. In flight, their wings appear broad. The head and neck becomes cinnamon in breeding adults (from March until August), but remain gray in juveniles and nonbreeding adults (from September through February). American Avocets have very thin, long upcurved bills which are slightly more upcurved in females. Their bills are black, and they also have long, pale bluish-gray legs.

Habitat/Where to find: American Avocets can usually be found feeding in open, shallow water(less than 20 cm deep) in a variety of wetlands including marshes, mud flats, ponds, alkaline lakes, rice fields, estuaries, salt ponds, and potholes. They are ccommon west of the Great Plains during the breeding season, and uncommon in the East. American Avocets breed along the west coast of California, in southeast Washington, southern Idaho, eastern Oregon, eastern California, and wetlands associated with Great Salt Lake. They breed as far north as southern Alberta, as far east as western Kansas and south to the Gulf Coast.

Sounds: American Avocets mainly produce single note calls, ranging from a high sharp “kweep” to a lower “pwik” and a melodic “pleek”. They also produce repeated calls including “whick”, “whuck”, and “oo-oo”.

Behavior: In flight, American Avocets extend their head and necks, but they normally walk or wade, shaking their feet to remove mud when exiting the water. During foraging, they are often trailed by Wilson’s Phalaropes that consume food stirred up by the avocets. Male and female American Avocets participate in an elaborate courtship ritual that involves bowing, wading, crouching, dancing, and extending the wings. To protect nests and young, American Avocets dive-bomb potential predators and produce diversionary antipredator displays including falsely mimicking incubation behavior away from the nest.

Reproduction: American Avocets breed monogamously in loose colonies and produce a single brood per season with a new mate each year. They place their nests in tufts of vegetation on gravel, sand, and mud flats. Three to four eggs are incubated by both sexes for 22-29 days, although the male incubates more frequently for the first 8 days. The young leave the nest soon after fledging and although they are tended by both adults, the young feed themselves. The young achieve flight at 28-35 days after hatching and sometimes one or both adults remain with the brood after this fledgling period.

Food Habits: American Avocets eat primarily aquatic invertebrates including insects, shrimp, and crustaceans, but 1/3 of their diet consists of seeds and aquatic vegetation. They usually forage in shallow water by sweeping their bill back and forth beneath the water’s surface, and finding food by touch. American Avocets commonly feed in large flocks greater than 100 birds walking in unison.

Vital Statistics: There are few records and no systematic studies of survivorship or longevity of American Avocets. The scant evidence that does exists suggests that American Avocets are capable of breeding in their first year, but normally do not breed until their second year. The longevity record is 8 years, but they probably live much longer since the longevity record for the closely related Pied Avocet is 24 years.

Migration/Dispersal: Very little information exists regarding the dispersal of young American Avocets, but a small proportion return to breed in their natal area. On the other hand, the seasonal movements are fairly well understood. American Avocets winter in the Central Valley of California, in coastal wetlands from central California to Central America, in central Mexico, along the Gulf Coast from Texas south to the Yucatan Peninsula, and along the Florida coast and southeast Atlantic coast.