2 minute read

Stilts and Avocets: Recurvirostridae

Behavior And Reproduction

A few species of stilts and avocets, such as black-winged stilts, pied avocets, and American avocets, migrate from breeding grounds to wintering grounds over the course of the year. Ibisbills migrate altitudinally, moving from higher to lower elevations and back. In addition, most species move short distances to find suitable wetland areas.

Most species of stilts and avocets form large flocks while feeding. Flocks can include several thousand individuals. In most cases, feeding occurs during the daytime. However, some stilts also feed at night. Stilts and avocets generally roost, or spend the night, standing in water. They may also rest during the day, either sitting on the ground or standing on one foot with the head tucked under the wing. Unlike other members of the group, ibisbills are usually found alone, in pairs, or in much smaller groups that rarely exceed seven or eight individuals.

Except for the ibisbill, stilt and avocet species also nest in large colonies, groups, which may include multiple shorebird species. Breeding colonies tend to be very noisy. Stilts and avocets use a variety of calls to communicate with mates or offspring, or to signal danger.

CROSS-BREEDING IN AN ENDANGERED STILT

The black stilt, which is found exclusively in New Zealand, is endangered for a variety of reasons. Wetland habitats have been destroyed by humans, and mammals not originally found on New Zealand eat black stilt eggs. Black stilts also cross-breed, that is, mate with individuals of other species. In the case of black stilts, cross-breeding occurs with black-winged stilts, which are also found on New Zealand. There are now fewer than one hundred black stilts left in existence.

Most stilts and avocets are monogamous (muh-NAH-guh-mus), with a single male breeding with a single female at one time. Birds may change mates over the course of a breeding season, however. To attract females, males perform a display that involves dipping their heads, shaking, and then preening, or smoothing their feathers. After mating, the male and female cross bills and walk together, the male holding one wing over the back of the female. Generally, the female lays three or four eggs at a time. Both the male and the female participate in incubating, or sitting on the eggs, and feeding and protecting the chicks once they hatch. Adults dive-bomb potential predators and may also fake a broken wing in order to distract intruders and draw them away from the nest.


Additional topics

Animal Life ResourceBirdsStilts and Avocets: Recurvirostridae - Physical Characteristics, Diet, Behavior And Reproduction, Conservation Status, Black-winged Stilt (himantopus Himantopus): Species Accounts - GEOGRAPHIC RANGE, HABITAT, AVOCETS STILTS AND PEOPLE