By Jan TenBruggencate
Advertiser Columnist

A female po'ouli, that rarest of Hawaiian forest birds, eluded biologists who went deep into the Maui rainforests five times this year to catch her.

"It was almost as if she knew where the mist nets were," said Eric VanderWerf, Hawaiian bird recovery coordinator for the U.S. Fish and Wildlife Service.

Other birds weren't so smart. The team captured 256 other forest birds — nine kinds — in the very fine, almost invisible netting. Those birds were banded and released.

There are only three po'ouli left, believed to be one male and two females. They inhabit different areas, and apparently are so faithful to their own territories that they never meet. Wildlife officials had concluded that the only way to save the po'ouli is to bring them into captivity in hopes that they will mate and produce young.

A team planned six trips into the Hanawi area on the wet slopes of Haleakala. Weather was so bad that one of the trips was canceled, and during the other trips, mist nets could be deployed only about half of the time.

VanderWerf said the team hopes to try again — this time trying first for the male — late this year or early next year. In any case, they hope to have a pair or all three in captivity by early next year. The po'ouli breeding season is believed to be from March to June.

Bird experts from the San Diego Zoological Society have used related species to develop techniques for raising Hawaiian forest bird young, and hope to use those techniques on the po'ouli.

VanderWerf said the small bird, which was only discovered during the 1970s, may have a couple of traits that make it particularly vulnerable in today's Hawaiian forests. First, it feeds and seems to nest fairly low in the forest understory, where it is susceptible to being killed or its eggs and chicks taken by rats and cats. It also feeds heavily on small native snails whose numbers have declined, partly because of a large, introduced cannibal snail.

Rats have been identified as a major threat to forest birds. State and federal officials are undertaking efforts to protect the bird through the control of rat populations in the Hanawi area, so that po'ouli have a safe place to go if captive rearing efforts are successful.

An earlier effort to save the species involved capturing the same female that was so elusive this year. The bird was carried to the habitat of the male, and released. She stayed the night in the area, but in the morning she started making her way to her home territory. It is not known whether the female and male ever actually saw each other.

For the upcoming efforts to capture the birds, "we need better weather and better luck," VanderWerf said.

Jan TenBruggencate is The Advertiser's Kauai bureau chief and its science and environment writer. You can call him at (808) 245-3074 or e-mail jant@honoluluadvertiser.com.