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State kills over 80 bears in Southwest Alaska in second-year effort to boost caribou

Zaz Hollander, Anchorage Daily News on

Published in Science & Technology News

State wildlife officials have now killed a total of 180 brown bears on Southwest Alaska caribou calving grounds in just over a year as part of a contested strategy to restore the renowned Mulchatna herd.

Shooting from a helicopter between May 10 and June 5, Alaska Department of Fish and Game employees killed 81 brown bears and 15 wolves they spotted across 530 square miles of tundra, officials said this month.

In 2023, the first year of the program, state employees killed 94 brown bears including some cubs, five black bears and five wolves.

State wildlife officials say killing bears feeding on newborn calves is a last-ditch attempt to shore up a herd that has declined from a peak of 200,000 animals in 1997 to just over 13,000 today. The state halted all hunting of Mulchatna caribou in 2021 with a goal of reaching a herd size of 30,000 to 80,000 animals.

Wildlife officials now say the strategy is working: Calf-cow ratios used to measure summer calf survival nearly doubled last fall compared to a 10-year average, according to a June 14 Department of Fish and Game advisory.

"Based on last fall, I anticipate we're going to see another pretty strong showing of calves pretty quickly," said Ryan Scott, the state's top wildlife official.

But the new data comes amid ongoing questions in the scientific community about the role predators play when it comes to caribou survival compared to other factors like disease and access to the low-growing lichens the animals eat.

When the Alaska Board of Game first approved the bear kill in 2022 as an expansion of an existing wolf control program that wasn't working, Fish and Game biologists who studied the Mulchatna herd called malnutrition and infection bigger factors in caribou declines than predators.

Even now, two years into the project, the state still doesn't appear to have data that establishes killing bears will definitively boost caribou numbers, according to several retired biologists interviewed for this story.

The improved calf-cow ratios announced this month may reflect a population recovering from brucellosis, a disease that can lower calf survival, rather than the effect of fewer bears, said Ken Whitten, a former Fish and Game wildlife biologist living in Fairbanks.

Whitten said the state's own data indicated that bear predation was not a serious problem for newborn caribou, "especially for the western segment of the herd, which is where the control occurred."

The state's bear-kill numbers this month also come amid growing questions about the role climate change may be playing in the collapse of caribou populations in North America, including Alaska's Western Arctic and other herds, including the Mulchatna.

Jim Dau, a Kotzebue-based caribou biologist who retired from the Department of Fish and Game in 2016, said the concern among his peers is that a "really aggressive" predator removal program was enacted without knowing how many bears move through the area or just what's driving the herd declines.

"The overriding concern for me is how climate change is affecting caribou worldwide," Dau said. "If we just continue to throw our time and resources into hacking out bears and wolves, we could be missing a lot of other things."

Dau said he's seen winter rains that freeze snow into a crust that animals can't penetrate to vegetation below, as well as brushy shrubs replacing the low-growing lichen on which caribou rely.

 

Scott, director of the state's Division of Wildlife Conservation, said he agrees climate change is probably affecting many Alaska caribou herds, including the Mulchatna population, in those ways.

There's "very little we can do to impact that in a positive way," he said. "But we know that bears and wolves eat the calves and it's the one lever that we can pull to try to make a positive impact."

Fish and Game wasn't able to put radio collars on newborn calves last year to track and study them closely — a point of contention with predator control critics — but have collared 42 calves this year, Scott said. The agency is also trying to learn more about what led to the deaths of calves that didn't survive, he said.

According to this month's advisory, wildlife officials are also conducting nutritional research and disease monitoring "to determine if further bear and wolf reductions during spring calving are warranted to further improve calf survival and herd growth."

The predator control program is authorized through 2028. The state intends to conduct it for at least one more year, Scott said.

The Mulchatna program cost nearly $309,200 last year, officials say. An estimate for this year's program wasn't available this week.

Wildlife officials say that they are operating under a mandate from the state's "intensive management" law that requires action when caribou numbers drop below a certain level.

The Mulchatna range includes the Togiak National Wildlife Refuge and villages in the Bristol Bay area. State officials say residents in 48 communities depend on the herd for food.

[Previously: Lawsuits target Alaska predator control program that killed 99 bears in effort to boost caribou]

Resolutions at last year's Alaska Federation of Natives conference included support for Mulchatna predator control. The Association of Village Council Presidents, which represents 56 federally recognized tribes, sent the Board of Game a letter last fall supporting "all possible measures to protect the herd" including predator control and limiting hunting to subsistence only.

This month, state wildlife officials said bear and wolf populations are "healthy" in Western Alaska and prior research indicates "a full recovery to pretreatment levels" within a few years.

Whitten, the retired biologist, called that contention "pretty much speculation" because bears don't reproduce fast enough for a population to recover that rapidly, though new bears can move into the area.

"As to what the long-term effects are, how quickly bears will recover within this area, those are things we don't know," he said.


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