Native honeycreepers surviving avian malaria
HILO » Two native Hawaiian forest birds on the Big Island are making a comeback in the lower elevations, where avian malaria killed off many of their predecessors, researchers said.
The Hawaii amakihi is common in forests above 3,000 feet, and until recently was rare at lower elevations because of the disease that is carried by mosquitoes.
Studies over the last two years have shown a dramatic increase in the number of amakihi and apapane, another Hawaiian honeycreeper, at sea level in lower Puna.
Bird counts in areas previously surveyed in 1994 showed significant increases in both birds, according to Patrick Hart, a biology professor at the University of Hawaii-Hilo, part of the team of researchers who discovered the birds resistant to avian malaria.
Hart said he believes the birds are spreading along the coast, and predicted the two species of Hawaiian honeycreepers could begin turning up in Hilo back yards within a decade.
Hart has already detected the bird in Hawaiian Paradise Park.
"I heard the first one in my back yard a month ago," he said.
Hawaiian forest birds are susceptible to avian malaria, which can kill 65 percent to 90 percent of those receiving even a single bite from an infected mosquito. The birds that survive can become carriers and spread the disease.
About 90 percent of the amakihi and apapane caught and tested in lower Puna previously had contracted avian malaria but survived, according to Hart and his former colleagues from the Pacific Island Ecosystems Research Center in Volcano.
The birds found in lower Puna are believed to be descendants of birds that had previously lived there and survived the disease.
"I don't think they ever completely disappeared from lower Puna," Hart said.