NATURE’S NOTEBOOK
Black-Necked Stilt
They aggressively defend territory against predators or human disturbance while vocalizing vigorously in flight.
The black-necked stilt ( Himantopus mexicanus) is part of the Recurvirostridae family, which includes stilts and avocets. It ranges from the United States through central South America and into the West Indies and is a breeding resident of central and south Florida. It is rare to absent or scattered locally in the northern peninsula, panhandle and Keys.
This striking-looking bird is boldly pied, white below and black above. Its dark head has a white spot behind and above the eye. It also has very long red or pink legs. The breeding male has red legs and a glossy black back, while the female has brown tones in the center of the back. Both sexes have long, thin, black bills.
Juveniles are paler than the adults. The primaries and secondaries are tipped white, which are visible only in flight. Their legs are grayish pink.
In flight the adult has black wings and a white rump and tail, which forms an inverted V on its back. This large shorebird is 14- 15 inches long with a wing span of 29 inches. It has a piercing, loud kek kek kek call, especially when nesting.
The black-necked stilt is found mostly in freshwater wetlands, marshes, wet savannas, mud flats, shallow ponds and lakes, phosphate mining lakes, flooded agricultural fields and in shallow saline or brackish wetlands. It feeds in shallow wetlands from the bottom substrates and from the water surface. Prey includes small fish, frogs and aquatic or terrestrial invertebrates such as insects and crustaceans. Other prey includes seeds, tadpoles, brine flies, snails, brine shrimp and crayfish. Small fish prey includes mosquitofish, flag fish and least killifish. It walks slowly in shallow to moderately deep water and swishes its bill from side to side or occasionally submerges its head while feeding on the bottom substrate. It feeds both by day and night.
Breeding season runs from April through September. During the nesting season black-necked stilts are seen in small groups
or in pairs. In winter they can be seen in large flocks numbering more than 100 individuals. Adults can breed at one to two years. They aggressively defend territory against predators or human disturbance while vocalizing vigorously in flight. During courtship the male walks around the female flicking water with its bill. Before copulation they perform elaborate bill-dipping and preening displays. The male pecks the water or ground and preens his breast while the female elongates.
Nest building generally starts in April to May. Black-necked stilts are monogamous during the breeding season. They are different from other shorebirds in that they often breed in loose colonies. They may even nest with other waterbirds such as grebes, terns and gulls.
Both sexes share nest-building duties. The nest may be created as a shallow scrape in the ground that is sparsely lined with debris, shells and pebbles. They select nesting sites on dry ground or in wet areas with a 360-degree view. The nest may be concealed or in open view. When locating near water they may build a more substantial nest into a large mound of grassy vegetation. If the water level rises, the stilts will quickly add vegetation to elevate the nest.
On average the female lays four eggs. The 1.7-inch-long eggs are subelliptical to oval in shape with a brownish buff that is blotched with brown and black markings.
Only one brood is produced each year. Incubation is conducted by both the female and male for 18 to 27 days. Most eggs hatch within one to two days of each other. Chicks become independent when they are able to fly in 28 to 55 days after hatching. The precocial young are covered in down when they hatch and can leave the nest within a few hours to 24 hours after hatching.
Both sexes tend and care for the chicks, which can feed themselves immediately after hatching. Initially the chicks rely on their parents for warnings against predators. Stilts protect their nest and chicks using different distraction displays to chase or lead predators away. These displays include a broken-wing act, direct attacks and false brooding behavior.
The North America population appears to be large and stable. Annual survival of adults is estimated at 80-90 percent. The blacknecked stilt can live up to 14 years.