The huge Porcupine Caribou Herd that ranges between Alaska and Canada may have reversed a decline that had cut its size by nearly a third.
Biologists with the Alaska Department of Fish and Game say preliminary results from a July aerial count make them confident the herd will show a population "significantly greater" than the 123,000 animals last counted a decade ago.
The Porcupine herd is Alaska's second largest, behind the Western Arctic herd, which was estimated at 401,000 caribou in 2009. It is the fifth-largest herd in North America and is jointly managed by Alaska and Canada
The animals roam between the mountains of Yukon Territory and the Arctic coast in Alaska and Canada, often crossing the Porcupine River during their spring and fall migrations.
People from Arctic Village in Alaska, Old Crow in Canada and other villages have long hunted the animals.
Because the Porcupine herd often calves on the coastal plain of the 19.6 million-acre Arctic National Wildlife Refuge, its health has been part of the debate over whether oil drilling should be allowed there.
"This is good news for people who value this herd," said Beth Lenart, a Fish and Game area biologist.
That includes Canadian hunters, who have been limited to a harvest of one bull amid concerns the herd was declining.
"Our prayers have been answered," Gwich'in leader Darius Elias, a member of the Yukon Legislative Assembly, told Whitehorse radio station CHON-FM on Friday.
"We were so worried by the migration patterns, by seeing a lot of different behavior patterns of the herd. It's pretty remarkable that this is probably about 30,000 caribou over what we believed to be the estimate of the herd."
YEARS OF FAILED COUNTS
Fish and Game spokeswoman Cathie Harms said the estimate was being released before the numbers are final so that Canada's Porcupine Caribou Harvest Management Plan and Yukon hunting regulations, scheduled to be reviewed next month, could consider the new estimates.
"A healthy herd size today does not prevent problems tomorrow," warned John Edzerza, provincial environment minister for the Yukon, "especially given the sharp declines many other caribou herds in the north are experiencing."
Five photo censuses between 1989 and 2001 showed the Porcupine herd declining from 178,000 to 123,000 animals. Alaska and Canadian biologists worried that the decline might have continued or worsened.
Counting caribou can be tricky, and several efforts to do so over the last decade have been thwarted.
In 2003, the herd failed to aggregate, or form groups large enough to make counting feasible.
In 2004, smoke from forest fires obscured visibility.
In 2005, the herd again was dispersed due to a cold spring on the North Slope.
In 2006, the herd failed to aggregate again.
In 2007, animals grouped up better but largely in mountainous areas where shadows obscured visibility.
Finally, in July, "the stars aligned," said Harms, allowing an aerial count in favorable weather with caribou bunched up. Biologists were able to locate all the animals wearing radio collars.
"This was a good one," Harms said. "We're very confident in the numbers. We can confidently say we're above where we were last time. The herd has grown."
Between four and six planes were used in the two-day count.
HUNTERS: LOOSEN RULES
The Porcupine herd moves in a rhythm that has been repeating for centuries. Typically, they remain north of the treeline until snow drives them into winter ranges in eastern Alaska and the Yukon.
They routinely head for the same area each spring unless snow conditions prevent it, typically calving in the so-called "1002 section" of the Arctic National Wildlife Refuge. Food is plentiful, predators are scarce and there is some sanctuary from the biting flies that descend in July.
Even before Fish and Game's new estimates, some of Canada's First Nations governments were unhappy with the Yukon government's hunting restrictions, including the ban on cows and a limit of one bull per hunter. New data is likely to increase pressure to loosen restrictions.
According to CBC News, officials with the Tr'ondek Hwech'in First Nation in Dawson City, Yukon, said the government overstepped its boundaries with the restrictions, which also require First Nations and other hunters to report their kills at mandatory checkpoints.
Hunter William Koe told CBC in 2009 he disagreed with the restrictions.
"It's our traditional way," said Koe, who is also subchief of the Tetlit Gwich'in Council in Fort McPherson. "We always hunt cows at that time because it's the only time they're good. The bulls are poor and not fat anymore, and (it's) no good to hunt bulls at that time."
Fish and Game began reviewing the aerial photos in late December. Officials must also make sure caribou aren't counted twice, or that a piece of lichen-colored rock hasn't been recorded as a caribou -- sometimes the resemblance can be remarkable.
"But we are at the point where we are convinced the herd has grown beyond 123,000," Harms said.
By MIKE CAMPBELL