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Liba discovered that 'akis actually lived in higher densities in ten-year-old koa stands
than they did in the old-growth koa forest of Hakalau Forest National Wildlife Refuge. She
mapped home ranges at Hakalau Forest and on her study site covered by young koa trees at
Keauhou Ranch, on the western side of the Big Island. “In the Hakalau refuge, 'akis have
home ranges that roughly fit together like pieces in a jigsaw puzzle,” she said, referring to the
territories 'aki pairs had carved out for themselves. But she found the opposite to be true in
the young stands at Keauhou: there, 'akis seemed not to be as territorial. Their home ranges
overlapped almost entirely, with males defending females rather than chunks of forest. There
are two parts to the explanation for this: first, she documented that 'akis spend about 90 per-
cent of their time foraging on koa; second, she suggested that young, thick stands of koa of-
fer a much higher density of food than do scattered giant koas in mature forests dominated
by 'ōhi'a trees, such as Hakalau Forest's old growth. “In short,” she concluded, “more food,
more 'akis.” Biologists working on other species, such as carnivores, show that territoriality
becomes relaxed when the food supply is so abundant there is no need to defend parcels of
land as hunting grounds. Such behavior would represent wasted energy, and there would be
selection against it.
'Akis were fortunate that a real woodpecker or sapsucker never landed on the Big Island
or was introduced by some misguided bird lover. Without a sapsucker around to compete
with, the 'aki literally tapped into the most common tree on the island. Liba's findings also
provided an important insight into how to conserve other rare species in a similar predica-
ment. That 'akis seemed actually to be nesting and raising young in the even-aged koa forests
with no difference in reproductive success was particularly exciting to her. “This means that
perhaps we could plant koas elsewhere on the Big Island and both provide habitat for an en-
dangered species and provide landowners with a tree 'trust fund' for their grandchildren.”
My puzzled expression indicated to her that I didn't immediately see the connections. I un-
derstood the first part: if 'akis and perhaps many other presumed old-growth-dependent bird
species can reproduce well enough in immature forests, this is a measure of their resistance
and resilience to extinction, and carefully designed forest regeneration programs could be
truly beneficial to them.
Liba grew more animated. “Did you know that a koa dining room set goes for $12,000?
And that individual koa-wood bowls turned on a lathe go for between $500 and $1,000?”
Koa, Hawaii's premier hardwood, is referred to in some circles as “Hawaiian mahogany.”
The tree is also important culturally, and some people were now planting koas to grow canoe
logs for traditional purposes. “Koa stands,” she observed, “could provide a 'win-win-win'
for saving the 'aki, bringing an economic return, and honoring Hawaii's traditional heritage.”
Provided, of course, that the koa seedlings are planted above the mosquito zone.
Liba's hopeful story contrasts with David Steadman's ecological history, which tells us
that the prospects for many island bird species are grim. Steadman's long view concluded that
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