One-third of the nation's endangered birds are in Hawaii, said the report issued Thursday by the Interior Department. Thirty-one Hawaiian bird species are listed as endangered, more than anywhere else in the country.

"That is the epicenter of extinctions and near-extinctions," said John Fitzpatrick, director of the Cornell Lab of Ornithology, which helped produce the study. "Hawaii is (a) borderline ecological disaster."

Hawaii's native birds are threatened by the destruction of their habitats by invasive plant species and feral animals like pigs, goats and sheep.

Diseases, especially those borne by mosquitoes, are another killer.

One of those in trouble is the palila, a yellow-crowned songbird that lives on the upper slopes of Mauna Kea. Its population plunged by more than 60 percent from 6,600 in 2002 to 2,200 last year.

Habitat loss and predators are part of the problem, said Holly Freifeld, a vertebrate recovery coordinator with the U.S. Fish and Wildlife Service in Honolulu.

Another is that grazing feral sheep ruin mamane trees, which provide palila birds with their preferred food: mamane seed pods. The trees are also being killed by disease.

The Fish and Wildlife Service plans to fence off an area on Mauna Kea, and remove sheep from the fenced area, to give the palila an environment where it can flourish, Freifeld said in an interview.

The restored habitat would also likely help other endangered birds which also have lived in the same forest ecosystem, she said.

Similar habitat restoration projects have worked in the Hakalau Forest National Wildlife Refuge.

Workers there installed fences, controlled invasive plant species, removed pigs, and planted koa and ohia trees.

The Interior Department's report, called "The State of the Birds United States of America 2009," noted Hakalau's populations of the Hawaii creeper and akiapolaau have increased dramatically.

"Application of these successful methods is urgently needed elsewhere," the report said.

Scott Fetz, wildlife program manager at the state's Division of Forestry and Wildlife, said he was confident such efforts could help restore all of Hawaii's endangered species, excluding those that have already become extinct.

"The basic, fundamental problem that we have is a lack of funding to do what we need to do," Fetz said. "If we had a lot more funding that we do, we would be able to recover most, if not all, of the species that we have that are endangered."

Fetz said legislation pending before Congress could provide a welcome boost. One would provide funding for restoration efforts. Another designed to provide money to help states cope with climate change would help Hawaii because warmer temperatures allow mosquitoes to enter habitats at higher elevations currently inhabited by the palila and other forest birds.

The U.S. State of Birds report was requested in October 2007 by President George W. Bush.

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On the Net:

State of the Birds report: http://www.stateofthebirds.org/

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