Wolf predation seen as the reason for the Caribou herd’s decline.... 

Fairbanks Daily News - Miner

Southern Alaska Peninsula Caribou Herd Recovers After Aerial Wolf Control

Published Tuesday, July 1, 2008

State wildlife biologists with the Alaska Department of Fish and Game shot and killed more than two dozen wolves from a helicopter last month to help a small caribou herd struggling to survive on the Alaska Peninsula.

It marked the first time since 1985 that ADF&G personnel have shot and killed wolves from the air as part of a predator control plan.

Biologists killed 28 wolves on the calving grounds of the Southern Alaska Peninsula Caribou Herd near Cold Bay, located about 600 miles southwest of Anchorage, to stop what has been a precipitous decline as a result of extremely poor calf survival. In the last six years, the herd has declined from 4,100 caribou to 600. Biologists have counted a total of only six surviving calves in the herd in the past two years.

Wolves from three packs were shot from a helicopter while on or near the calving grounds in late May and early June, according to a press release issued by the department on Friday.

So far, biologists are encouraged by the results of the air strike, which was approved by the Alaska Board of Game in March.

Biologists estimate 63 percent of the approximately 450 calves born this spring survived their first two weeks of life and both pregnancy rates — 90 percent — and weights of newborn calves indicate the herd is healthy, department spokesman Bruce Bartley in Anchorage said.

“That pretty much leaves predation” as the reason for the herd’s decline, he said.

While it’s too early to tell how many calves will survive the summer, most caribou calf mortality occurs during the first few weeks of life, according to the department. Telemetry flights will be flown periodically throughout the summer to document further mortality.

Biologists captured 65 newborn calves to be weighed and fitted with radio collars equipped with mortality sensors so biologists can track them and identify a cause of death if necessary.

“If they survive the summer as we suspect they will, we’ll probably have more calves survive this year than we’ve had the last several years combined,” Bartley said.

The latest figures show wolves are still the biggest killer of caribou calves, however. Of the 24 deaths documented by biologists among radio-collared calves in the first weeks after calving (36.7 percent of the total number of calves), wolves killed seven (10.8 percent) of the radio-collared calves, while bears accounted for five calf deaths (7.6 percent). Another four calves (6.1 percent) were killed by either wolves or bears, but biologists were not able to determine which one. Two calves drowned (3.1 percent) and one died of starvation (1.5 percent). The other five (7.6 percent) died of undetermined causes.

Though the herd ranges primarily within the Izembek National Wildlife Refuge and the U.S. Fish and Wildlife Service does not permit wolf control on federal lands in Alaska, its calving grounds are on state lands and both the department and game board felt the action was necessary to preserve the herd.

This is the first time in about 15 years that state wildlife biologists have actively participated in a wolf control program.

In the past five years, the state has relied on private pilots and gunners to kill wolves in different parts of the state where moose or caribou populations are too low to meet the needs and demands of subsistence and sport hunters. More than 800 wolves have been killed in the past five years as a result of the program.

Permitted pilot/gunner teams shoot wolves from the air or land and shoot them, practices that have twice been outlawed twice by Alaska voters in state ballot initiatives but were revived by the Alaska Legislature five years ago when it gave the Alaska Board of Game authority to approve citizen-based predator control.

But that program could be halted if a ballot initiative that would allow only ADF&G personnel to shoot wolves or grizzly bears from the air in the event of a “biological emergency” is passed in August. The initiative is on the Aug. 26 primary ballot.

The situation with the South Alaska Peninsula herd may very well have fallen into the biological emergency category, said Joel Bennett of Juneau, one of the initiative sponsors.

“It sure sounds like it would be a candidate for what we had in mind,” Bennett said. “The two key elements from our perspective is that the commissioner make the determination that it’s a biological emergency, not the Board of Game, and that it is based on adequate data, which in this case they would argue they have.”

While there is no definition for exactly what a “biological emergency” is, Bennett said it is basically a situation where a population will suffer an irreversible decline if something isn’t done.

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