Hawaiian Stilt

Himantopus mexicanus hawaiiensis / Ae‘o
Stilts

What do you hear as you get out of your car at the pond?  A friend called them the “Chihuahua of the wetland” because of their constant vocalization chatter.  Recognition, warning, whatever the purpose the ae‘o are the most prevalent of the endangered birds at Keālia Pond.

The ae‘o is a slender wading bird with black coloration extending from the forehead down the back of the neck and throughout the back. White covers the front of the face, down the front of the neck and underbelly. Their pink, long legs are almost as long as the bird’s body and are one of their identifying features. Females have a tinge of brown on the back whereas the back of males is black. The long legs and long bill allow the stilt to wade into the water further than other common shorebirds at Keālia Pond.

Ae‘o prefer shallow water no more than seven inches in depth. Nesting sites are on exposed mudflats and low islands with adjacent water (fresh, brackish, or salt water) and vegetation. Nests are either made from a pile of sticks or just a shallow nest depression on the ground.

The onset of ae‘o breeding season is when water level in the ponds recede and mudflats are exposed, usually in late March-early April at Keālia Pond NWR. Nests consist of vegetation material with a depression in the middle or just a depression in the soil. Four brown speckled eggs are laid and incubated approximately 24 days. Ae‘o chicks are precocious – once hatched they are mobile and feeding on their own, but under the watchful eyes of their parents. Chicks resemble their eggs with brown and off-white speckles until they obtain feathers similar to the adults. Breeding season, including chick fledging, is completed by mid August.

Movement of ae‘o between wetlands on Maui and other islands are known from sightings of color-banded birds. Ae‘o are vocal even during the nonbreeding season. They actively defend their nests and chicks with calls and dive-bombing to detract the predator or disturbances. Upon threat of predators or humans, adults vocalize to warn chicks who in turn will crouch down and remain motionless, using their camouflaged down to blend with the ground.

The ae‘o are the most vulnerable to nonnative mammalian and avian predators (cattle egrets) and are easily disturbed by human activities. During breeding season at Keālia Pond (April to July) areas of the Kanuimanu Ponds may be inaccessible to the public to allow birds to successfully incubate and raise their chicks.

Facts About Hawaiian Stilt

Diet
Invertebrates and other aquatic organisms (worms, crabs, fish)
Life Span
Unknown
Size
Length: 35–39 cm (13.8–15.4 in); wingspan: 71 cm (28 in)