Hawaiian stilt

Himantopus mexicanus knudseni / Ae‘o
Black and white bird with long legs in the water

The ae‘o is a slender wading bird that grows up to 15 inches in length. Black coloration extends from the forehead down the back of the neck and throughout the back and 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 endangered ae‘o subspecies differs from the North American black-necked stilt by having more black on its face and cheeks, and longer bill, tarsus, and tail.

The population of ae‘o is estimated at 1200-1500 individuals throughout the islands. The species was listed as endangered in 1970 as wetlands were being altered. Although ae‘o can be observed in ephemeral pockets of water throughout the islands, their habitat for foraging and success nesting is limited to protected areas where predators (mongooses, feral cats, rats, and feral dogs) are controlled.

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. 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.

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.

Facts About Hawaiian stilt

Invertebrates and other aquatic organisms such as worms, crabs, fish.

Shallow water no more than 7 inches deep. Nesting sites are on exposed mudflats and low islands with adjacent water and vegetation.