Black-necked Stilt

Black-necked Stilt exhibit a lively demeanor especially during the breeding season, engaging in unique courtship behaviors like synchronized preening, bill dipping, and the 'Popcorn Display' to ward off threats. Their social structure is semicolonial; they defend territories but collaborate against predators, using distraction tactics or even physical aggression. Although black-necked Stilt share parenting responsibilities, males often accompany older chicks. The species is territorial, with adults displaying aggression even towards non-offspring young. Outside the breeding season, their territoriality lessens, and while not as gregarious as avocets, they still rest and forage in proximity. Notably, black-necked Stilt exhibit the distinctive practice of roosting on one leg or sitting directly on the ground.

The black-necked stilt is found in estuarine, lacustrine, salt pond and emergent wetland habitats; it is generally a lowland bird but in Central America has been found up to 8,200 ft (2,500 m) ASL and commonly seen in llanos habitat in northern South America. It is also found in seasonally flooded wetlands. Use of salt evaporation ponds has increased significantly since 1960 in the US, and they may now be the primary wintering habitat; these salt ponds are especially prevalent in southern San Francisco Bay. At the Salton Sea, the black-necked stilt is resident year-round. This bird is locally abundant in the San Joaquin Valley, where it commonly winters. It is common to locally abundant in appropriate habitat in southern California from April to September. It also breeds along lake shores in northeastern California and southeastern Oregon as well as along the Colorado River. In North America outside California, the black-necked stilt rarely breeds inland, but it is known as a breeding bird in riparian locales in Arizona and elsewhere in the southern USA. In Arizona, black-necked stilts may be seen along artificially created lakes and drainage basins in the Phoenix metropolitan area, in remnant riparian habitat. In the San Francisco Bay Area, specific locations where one would expect to see this bird are Richardson Bay (especially, according to mudflat bird sightings, the mouth of Pickleweed Creek), mudflats of Belmont Slough, mudflats of Seal Slough in San Mateo, salt ponds in Hayward, California, exposed bay muds on the Burlingame estuarine shore, and Heron's Head Park at India Basin. For flocks that summer in the northern Central Valley of California, a migration occurs to the San Joaquin Valley to consolidate with flocks that were already summering there. In coastal areas flocks both summer and winter in these estuarine settings. Fall migration of the northernly birds takes place from July to September, and they return to the breeding grounds between March and May. Usually, the entire population breeding at any one site arrives, mates, incubates eggs for about a month, and protects and broods the young until they are capable of sustained flight (at 27–31 days old) and leaves again migrating in flocks of about 15 individuals sometimes juveniles congregating in small groups and other times siblings with family groups. There is some seasonal movement of the tropical populations, but this is not long-range and poorly understood. The parasitic cyclocoeline flatworm Neoallopyge americanensis was described from the air sacs of a black-necked stilt from Texas. Its genus is presently monotypic and seems to be closely related to the similar genus Allopyge, found in Old World cranes.