Measurements
Both Sexes
- Length
- 13.8–15.4 in
35–39 cm - Wingspan
- 28 in
71 cm - Weight
- 4.8–7.8 oz
136–220 g
Other Names
- Échasse d'Amérique (French)
- Candelero Americano, Cachiporra,Cigüeñuela, Cuellinegra,Monjita (Spanish)
Cool Facts
- Five species of rather similar-looking stilts are recognized in the genus Himantopus. They have the second-longest legs in proportion to their bodies of any bird, exceeded only by flamingos.
- The Hawaiian subspecies of Black-necked Stilt has the black of its neck reaching much farther forward than the mainland forms. Habitat loss and hunting led to the decline in its numbers. It uses primarily the few freshwater wetlands found on the Hawaiian Islands.
Habitat
Shore-line
Black-necked Stilts inhabit shallow wetlands from the western United States to Central America and parts of South America. In the United States, Black-necked Stilts are commonly found in salt ponds, flooded lowlands, or shallow lagoons. Human-maintained wetlands such as sewage ponds or flooded pastures are particularly suitable habitats for these birds, since such environments have some sparse vegetation without being too overgrown. The endangered Hawaiian subspecies, the Ae'o, lives in wetlands, mudflats, and ponds on all the major islands.
Food
Insects
Black-necked Stilts wade in shallow waters to capture their meals of aquatic invertebrates and fish. They often consume such fare as crawfish, brine flies, brine shrimp, beetles, water boatmen, and tadpoles. They peck, snatch, and plunge their heads into the water in pursuit of their food, and will herd fish into shallow waters to trap them there.
Nesting
Nesting Facts
- Clutch Size
- 1–5 eggs
- Number of Broods
- 1 broods
- Egg Length
- 1.5–2 in
3.7–5.1 cm - Egg Width
- 1–1.4 in
2.6–3.6 cm - Incubation Period
- 21–26 days
- Egg Description
- Olive-gray with brown speckles.
- Condition at Hatching
- Down-covered, alert, able to leave the nest within about 2 hours of hatching.
Nest Description
Male and female Black-necked Stilts trade off the job of constructing the nest. While one mate observes, the other scrapes into the dirt with breast and feet to form a depression about 2 inches deep. As they dig, they throw small bits of lining over their back into the nest. Most lining is added to the nest during incubation, and consists of whatever material is closest to the nest, including grasses, shells, mud chips, pebbles, and bones. Some nests are left unlined.
Nest Placement
Ground
Black-necked Stilts nest on the ground. They tend to build on surfaces above water, such as small islands, clumps of vegetation, or even, occasionally, floating mats of algae. Both female and male Black-necked Stilt choose the site; they look for places with soft substrate that can be scraped away to form the depression in which they nest.
Behavior
Probing
Black-necked Stilts wade for their food, and will only swim or dive when under duress. During breeding and during winter, they are strongly territorial birds, and are particularly aggressive to chicks that are not their own. When not breeding, Black-necked Stilts roost and forage in closely packed groups, often staying within a foot of each other. Black-necked Stilts are semicolonial when nesting, and they participate en masse in anti-predator displays. The displays include one in which nonincubating birds fly up to mob predators, and one in which all birds encircle a predator, hop up and down, and flap their wings.
Conservation
Least Concern
The Hawaiian subspecies, the Ae'o, is a federally endangered species. Its population has risen slowly in the last 30 years, but they still number fewer than 2,000. In continental North America populations appear stable or slightly increasing. Because stilts are wetland birds they are vulnerable to polluted runoff including pesticides and especially selenium. Stilts are sometimes monitored as indicators of contaminated irrigation water in the environment at large. In Hawaii, invasive aquatic plants deprive stilts of open water and mudflats. In the nineteenth century stilts were hunted throughout their range.
Credits
- Robinson, J. A., J. M. Reed, J. P. Skorupa, and L. W. Oring. 1999. Black-necked Stilt (Himantopus mexicanus). In The Birds of North America, No. 449 (A. Poole and F. Gill, eds.). The Birds of North America, Inc., Philadelphia, PA.