Endangered Species in the Pacific Islands
Hawaiian Common Moorhen / Gallinula chloropus sandvicensis / ‘Alae ‘ula (“red forehead”)
||The ‘alae ‘ula is a dark gray bird with a black head and neck, and white feathers on their flanks and on their undertail coverts (or feathers). They have a very distinctive red frontal shield, and their bill tip is yellow with a red base. Their legs and feet are greenish and without lobes. The ‘alae ‘ula measures about 13 inches (33 centimeters) in length. Both sexes are similar and have chicken-like cackles and croaks.
|Hawaiian moorhen - Photo credit Brenda Zaun/USFWS
Habitat & Behavior:
The ‘alae ‘ula is known as the most secretive native waterbird. In Hawaiian legend, these birds were thought to have brought fire from the gods to the Hawaiian people. These secretive birds can be found in freshwater marshes, taro patches, irrigation ditches, reservoirs, and wet pastures. They favor dense emergent vegetation near open water, floating or barely emergent mats of vegetation, water depths of less than 3 feet (1 meter), and prefer fresh water as opposed to saline or brackish water.
These birds nest year-round but the active season is usually from March through August. It is believed that the timing of nesting is related to water levels and vegetation growth. The ‘alae ‘ula usually lays an average of 5 to 6 eggs and incubation is 19 to 22 days. The ‘alae ‘ula eats mollusks, insects, water plants, and grasses. They are good swimmers and chicks can swim shortly after hatching.
Past & Present:
No historical population estimates are available for the endemic ‘alae ‘ula. Because they are such secretive birds, it is difficult to conduct surveys of this species. It is believed that they were common on the main Hawaiian islands in the 1800s but radically declined by the mid 1900s. Surveys in the 1950s and 1960s estimated no more than 57 individuals. However, the spread of aquaculture in the 1970s and 1980s helped boost their numbers by providing more suitable habitat for these birds.
Today, ‘alae ‘ula can be found only on O‘ahu and Kaua‘i. The Kaua‘i population is found in lowland wetlands and valleys. A sizable population is found at the Hanalei National Wildlife Refuge. The O‘ahu population is widely spread but is mostly found between Haleiwa and Waimanalo. Six marked ‘alae ‘ula were released on Moloka‘i in 1983 but they have not been seen since 1985.
The primary causes of the decline of this Hawaiian native waterbird has been the loss and degradation of wetland habitat and introduced predators (e.g., rats, dogs, cats, mongoose). Other factors include alien plants, introduced fish, bull frogs, disease, and sometimes environmental contaminants.
State and Federal efforts in protecting wetlands, enforcing strict hunting laws, educating, and working with private organizations and landowners play an important role in ensuring the livelihood of the ‘alae ‘ula and many other waterbirds. Private organizations, such as Ducks Unlimited, have been actively supporting wetlands conservation.
The ‘alae ‘ula was listed as an endangered species in 1967 under the Federal Endangered Species Act. The Hawaiian Waterbirds Recovery plan was completed in 1978, revised in 1985, and is currently being revised and updated again.