Two Species of Hawaiian Birds Are Classified As Endangered

(Click on image to enlarge) Photo courtesy Dr. Eric VanderWerf The Akikiki, a Hawaiian honeycreeper, has an estimated population of 1,400 birds. (Click on image to enlarge) Photo courtesy Dr. Eric VanderWerf The Akekee, another Hawaiian honeycreeper, has an estimated population of 3,500 birds.

Two Hawaiian birds, the Akikiki (Oreomystis bairdi) and Akekee (Loxops caeruleirostris), have been classified as endangered under the Endangered Species Act (ESA). Both honeycreeper species inhabit the Hawaiian island of Kauai, where the estimated current population is less than 1,400 for the Akikiki and 3,500 for the Akekee, based on surveys conducted in 2007. The designation by the U.S. Fish and Wildlife Service (USFWS) means that the birds will receive protection in several ways.

Once the species is listed, the full effect of the Endangered Species Act kicks in,” said American Bird Conservancy vice president and director of the Oceans and Islands Division, George Wallace. He explained that various sections of the act provide different benefits, and the species are protected directly against take and against harm. The Endangered Species Act defines “take” as “harass, harm, pursue, hunt, shoot, wound, kill, trap, capture or collect.” The word “harm” may include significantly modifying habitat “where it actually kills or injures a listed species through impairment of essential behavior, e.g. nesting or reproduction.”

The geographic range occupied by the Akikiki has declined from about 34 square miles in 1970 to about 14 square miles in 2000. Threats to the population include predatory animals, loss and degradation of habitat and avian malaria, transmitted by mosquitoes.

Mosquito population rise has resulted from increased habitat range and breeding areas, caused by feral ungulates such as pigs. Feral pigs create wallows in the soil and chew the bases of tree ferns creating shallow, rain-collecting cavities where mosquitoes breed.

Mosquitoes prefer warmth and will not venture above certain elevations, but Kauai’s low elevations mean that birds are exposed to mosquitoes and malaria at all elevations. The Akikiki and Akekee are particularly susceptible because they have no innate resistance to avian malaria, Wallace says. Reducing the impacts of malaria and other threats will aid the birds’ recovery.

“Invasive plants and ungulates degrade habitat, and mammals, such as cats and rats, prey directly on the birds,” Wallace said. “One of the most effective things is to fence habitat and exclude feral ungulates. In a lot of cases if you restore the habitat you can increase bird populations.” 

Every year, U.S. Fish and Wildlife releases millions of dollars to Federal and State agencies that work to conserve endangered species. Now that the Akikiki and Akekee are listed, Wallace says, a recovery team must develop a plan for conserving the species and devote money to it. He encourages this kind of conservation effort, especially in Hawaii.

“It would be an understatement to say that Hawaiian birds are in tough shape,” he said. “However, when we apply funding and conservation efforts, we can solve problems.”

Other additions to the federal endangered species list include an additional 46 species (both plants and animals), all unique to Kauai. The list comprises 45 plants, the two honeycreepers and a Hawaiian picture-wing fly.