SOMBA K'E/YELLOWKNIFE - The Bluenose-East caribou herd has made a somewhat sudden and surprising rebound.

According to results from two 2010 summer surveys, the herd has recovered to 2000 levels, and has increased by almost 40,000 animals since 2006.

"The new estimate of the size of the herd is 98,600 animals," said Michael Miltenberger, the minister of Environment and Natural Resources (ENR), in a news release. "While the increase in the herd is good news, this herd is shared by many harvesters from many regions and we must still exercise caution when recommending management actions so the herd can continue to increase."

It is still to be seen how the new population estimate will affect a proposed harvest target of 2,800 animals for all regions over the next three harvesting seasons made by the Tlicho's Wek'eezhii Renewable Resources Board (WRRB) on Oct. 8.

"It's not a recommendation as such," said Jody Snortland, the board's executive director. "It would be presumptuous of the WRRB to set a target harvest for a herd that is harvested by other parties."

Wildlife co-management boards and aboriginal governments from the Sahtu, Deh Cho, Tlicho and Inuvialuit regions, along with Nunavut, will meet soon - hopefully before Christmas - to discuss the WRRB's proposed target.

"Whether it will be implemented or adjusted accordingly, that's to be determined by the four regions together, not by one board," Snortland said.

The meeting will determine what harvest limitations, if any, should be recommended to Miltenberger and how they should be allocated.

Snortland was surprised by the latest Bluenose-East population estimate, noting, "It certainly goes against what we're seeing happening in the other herds."

However, she added she is not questioning the estimate. "I would say ENR's estimate is as accurate as possible, and I wouldn't call into question any of their methods."

Two different survey methods were used and both provided similar estimates.

The estimate of 98,600, plus or minus 7,100 animals, is based on a post-calving photographic survey. A calving ground photographic survey estimate is 102,700, plus or minus 40,000 animals.

Observers from Sahtu, Akaitcho and Nunavut communities participated in both surveys.

"The increase is likely due to good calf recruitment since 2006 and reduced harvest pressure on cows since the bulk of the herd did not winter near winter roads or communities for the past four years," said Miltenberger.

Jan Adamczewski, an ENR wildlife biologist specializing in ungulates, was involved in both surveys.

"It's a little bit surprising in the sense that pretty much all our other herds have been declining or showing a stable trend," he said of the population estimate.

However, he said such rapid increases have happened in the past, both in the NWT and elsewhere.

In the early 1980s, the Bathurst, Beverley and other herds had a period of rapid increase.

Adamczewski said traditional knowledge from elders also shows rapid increases happen when the harvest is low, predator numbers are low and there is good calf production.

The Bluenose-East increase is probably the result of a relatively limited harvest and really good calf numbers, he said. "You put those two things together and it's certainly possible for herds to start increasing. Of course, we hope that will also apply to the other herds."

Adamczewski is "fairly confident" in the accuracy of the latest population numbers for the Bluenose-East herd, noting the surveys were done in good conditions and with experienced people.

"They're all estimates," he said. "We never try to say that we know down to the last animal how many animals are in a herd."

When asked about the belief by some people that population variations in caribou herds are simply the result of animals migrating to other herds, Adamczewski said studies, especially with radio-collared animals, show "nothing exceptional" has happened.

"We're simply seeing the same low rates of exchange of animals between herds," he said.

Adamczewski said a few animals will go from, say, the Bathurst herd to Bluenose-East and vice versa.

"Typically, the rates of exchange are low, from two to five per cent among the collared animals, and the exchange works both ways," he explained, adding that makes the net exchange fairly close to zero.

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