American Avocet

The American avocet (Recurvirostra americana) is a striking wader, notable for its elegant stature and distinctive upwardly curved bill. Adults typically measure between 40 to 51 centimeters in length, with a wingspan stretching from 68 to 76 centimeters, and weigh between 275 to 420 grams. Their legs are a delicate pastel grey-blue, earning them the colloquial name "blue shanks." The plumage is a crisp black and white on the back, with a pure white underbelly. During the breeding season, they don a vibrant brassy orange on the head and neck, which fades to white and grey post-breeding.

Identification Tips

The American avocet's long, slender legs and slightly webbed feet are characteristic of waders. Its black bill is notably long, more than twice the length of its small, rounded head, and curves gently upwards. In breeding plumage, the head and neck are adorned with a rich, brassy orange, while in non-breeding plumage, these areas are white and grey.

Habitat

This species is found in a variety of wetland habitats, including marshes, beaches, prairie ponds, and shallow lakes predominantly in the mid-west and as far north as southern Canada.

Distribution

Once widespread across the United States, the American avocet was extirpated from the East Coast but has since reclaimed some territories. It breeds in the western and mid-west United States and parts of southern Canada. During migration, it can be seen across many western states, and it winters along the coasts of the Atlantic and Pacific Oceans, as well as the Gulf of Mexico.

Behaviour

Avocets are social birds, migrating in flocks of 50 to 300 individuals. They are known for their comfort movement of preening their feathers. During breeding, they establish territories and engage in copulatory displays. Post-breeding, they gather in large flocks, sometimes in the hundreds.

Song & Calls

The American avocet's call is a shrill and melodic "bweet," which rises in inflection. They have three distinct calls: a loud repeated "wheep" for the common call, a similar but faster "wheep" for the excited call, and a distressed screech for the broken wing call.

Breeding

Avocets breed in wetlands, laying 3-5 eggs, typically 4, in shallow ground nests lined with grass, feathers, or pebbles. Both parents incubate the eggs for 23-25 days and care for the precocial chicks, which can feed themselves shortly after hatching.

Anti-predator behavior

Pairs defend their territory vigorously against predators and other avocets. They employ distraction techniques and, if necessary, aggressive measures to protect their nests.

Diet and Feeding

The American avocet forages in habitats with fine sediments, feeding on brine shrimp in winter and primarily brine flies during the breeding season. They employ both visual and tactile feeding methods, including pecking, plunging, snatching, bill pursuit, filtering, scraping, and scythe feeding.

Conservation status

After a decline due to shooting and trapping, the American avocet is now protected under the Migratory Bird Treaty Act of 1918. While it faces challenges such as habitat loss and contaminants, its numbers have remained steady, and there has been a recent increase in the eastern United States. The species is currently listed as Least Concern by the IUCN.