Crested Honeycreeper

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Crested Honeycreeper

Palmeria dolei

StatusEndangered
ListedMarch 11, 1967
FamilyDrepanididae (Hawaiian honeycreepers)
DescriptionHoneycreeper; primarily black with orange nape and bushy crest.
Habitat'Ohi'a forests.
FoodNectar.
ReproductionProbably mates in February and March; young hatch by May.
ThreatsHabitat destruction, predation, disease.
RangeHawaii

Description

At about 7 in (17.8 cm) in length, the crested honeycreeper (Palmeria dolei ) is the largest of the family Drepanidinae on Maui. It is primarily black and in poor light appears entirely black. The dark feathers are tipped with gray on the breast and throat, off-white on the wing and tail tips, and orange over most of the body. The bird has a prominent orange nape and ragged white crest. The thighs, orange or yellowish, can be very conspicuous in some light. Immature birds are duller and lack the orange tint and the crest. The Hawaiian name for this bird is 'akohekohe.

Behavior

The crested honeycreeper feeds primarily on 'ohi'a nectar but will use a variety of other flowers, such as those of the tree ohelo (Vaccinium calycinum ) and akala (Rubus hawaiiensis ), when 'ohi'a flowers are unavailable. No nests have ever been found, but the birds are thought to pair in February and March. Adults with juveniles have been seen in May.

Habitat

This species' known habitat is wet 'ohi'a forests on Maui and Molokai in the Hawaiian Islands. In 1980, 415 observations on Maui were recorded in an area of about 11,000 acres (4,451.6 hectares) at elevations from 4,200-7,100 ft (1,280.2-2,164.1 m).

Distribution

Historically, the crested honeycreeper was locally abundant on both Maui and Molokai. It was last seen on Molokai in 1907 and was not seen on Maui from about 1900-1942, probably because few ornithologists looked for it.

The population, now estimated at about 3,800 birds, occurs in two major groups on East Maui, separated by Koolau Gap. To the west of the gap, large numbers inhabit an area of about 4,000 acres (1,618.7 hectares), all privately owned. To the east, the honeycreeper's range extends nearly 6 mi (9.7 km) along a mile-wide swath of forest at 4,900 ft (1,493.5 m), then south to upper Kipahulu Valley and Manawainui.

Threats

The Hawaiian Islands have been extensively altered by human settlement. The magnitude of ecological changes is only now being appreciated. Large tracts of forest, especially on the dry leeward slopes, were cleared by the Polynesians for agriculture. European settlers eliminated all dry forest on Maui up to at least 5,000 ft (1,524 m) for pasture. By the turn of the twentieth century, almost all forestsexcept the higher elevation 'ohi'a forests were gone, and forest bird populations had declined precipitously. In much of the remaining forests, browsing and rooting by feral goats and pigs and axis deer have seriously disturbed native plants, allowing introduced plants to invade the habitat. The combined impact of feral animals and non-native plants has changed species composition, distribution, and plant densities, and these changes affect native birds. Avian diseases, especially pox and malaria, were spread by introduced mosquitoes and played a large role in the decline of many native Hawaiian birds. In addition, predation and competition with introduced bird species have taken their toll on forest birds.

Conservation and Recovery

The State Reserve System holds and actively manages about 30% of the remaining forest resources of the islands, including those on Maui. The Nature Conservancy manages the Waikamoi Kamakou preserves. Haleakala National Park has implemented a program to control some exotic plants, and a portion of the Haleakala Crater district has been fenced. Since the crested honeycreeper could easily suffer a population crash while recovery efforts are studied and implemented, the U. S. Fish and Wildlife Service is exploring the possibility of captive propagation for it and other endangered forest birds. The ultimate goal would be the creation of a captive flock to furnish birds to supplement wild populations. Little is known, however, about the ability of Hawaiian forest birds to live and breed in captivity.

Contacts

U. S. Fish and Wildlife Service
Regional Office, Division of Endangered Species
Eastside Federal Complex
911 N. E. 11th Ave.
Portland, Oregon 97232-4181
(503) 231-6121
http://pacific.fws.gov/

Pacific Remote Islands Ecological Services Field Office
300 Ala Moana Blvd., Room 3-122
P. O. Box 50088
Honolulu, Hawaii 96850
Telephone: (808) 541-1201
Fax: (808) 541-1216

References

Scott, J. M., and others. 1988. "Conservation of Hawaii's Vanishing Avifauna." Bioscience 38 (4): 238-253.

U. S. Fish and Wildlife Service. 1984. "The Maui-Molokai Forest Birds Recovery Plan." U. S. Fish and Wildlife Service, Portland.