Shooting and trapping wolves won’t reduce the number of livestock-related deaths. But it will put wolves right back on the endangered species list, Washington State University researchers have found.
Wolves have moved south from protected lands on the U.S.-Canada border to repopulate the Washington Cascades. Pictured is a member of the Teanaway Pack, in the Cascades north of Cle Elum. A breeding female wolf from the pack was poached last month. Wildlife groups are offering a $15,000 reward. (Photo courtesy of Conservation Northwest).
When analyzing 25 years of data collected by the U.S. Fish and Wildlife Services Interagency in Montana, Wyoming, and Idaho, WSU wildlife biologist Rob Wielgus and data analyst Kaylie Peebles found that when a wolf is killed, the chances of livestock getting killed the following year increased – five to six percent for cattle and four percent for sheep.
For every 20 wolves killed, livestock deaths doubled. The researchers noticed that the trend didn’t reverse until 25 percent of wolves were killed.
“I had no idea what the results were going to be,” Wielgus said in a WSU press release. “However, I was surprised there was a big effect.”
Why shooting isn’t the solution
Wielgus isn’t completely sure why more livestock die when a smaller numbers of wolves are killed, but he does have a theory:
Wolf killings likely disrupt the social cohesion of the pack, he said. Packs are led by a male and female breeding pair. If one or both is killed, the pack can split up, increasing the number of breeding pairs and ultimately, the wolf population. Wielgus found that livestock loses decline only when enough wolves are killed because it overwhelms the wolves’ ability to keep up through reproduction.
However, Wielgus suggests that making a habit out of killing wolves is counter-productive. Either livestock losses go up or, if enough wolves are killed to reduce livestock deaths, the wolf population rate drops so low that they are right back on the endangered species list.
“It’s a bit of a catch-22,” Wielgus told National Geographic. “You can reduce them now, but you can only reduce them so far, and when you stop that heavy harvest, now you’re at maximum livestock depredation.”
History behind wolf killings
In the ranching world, shooting wolves has been a widely accepted practice. So much that it led to the animal’s eradication in the western U.S. in the 1930s. However, over the past 30 years, the wolf population has slowly grown from less than 300 to over 4,000.
Despite the resurgence of wolves in the mid-1990s, government officials and ranchers have relied on guns to cope with livestock problems – killing more than 2,000 wolves by 2013.
However, there have never been any large-scale studies showing whether killing wolves helps protect livestock.
Off the Endangered Species list
In 2011, wolves were removed from federal protection under the Endangered Species Act in Idaho, Montana, and parts of Washington, Oregon, and Utah. The result: making it easier to shoot them. (Wyoming was under the same verdict until a federal judge overturned the ruling this past September.)
Because of it, the wolf population in Montana and Idaho had surged to slightly more than 600 in each state, with 231 wolves killed in Montana and 356 in Idaho.
To make matters worse, Josh Bransford from Idaho made headlines for taking a photograph in front of a living wolf in a leg-hold trap surrounded by bloody snow in 2012.
As the picture went viral, the wolf debate escalated.
“If this is what passes as compliance with the Department of Fish and Game’s rules, there’s a serious problem with the adequacy of state regulation,” said Michael Robinson, a spokesman for the group in New Mexico, in a news release.
The Idaho legislature is not doing anything to help either. Last year, their state legislature created a Wolf Depredation Control Board to push wolf numbers to just above 150, a cutoff that could renew protection under the Endangered Species Act in that state.
Wolf problem in Washington
Washington has its own set of wolf problems. This past summer, wolves from the Huckleberry Pack in Stevens County killed more than 30 sheep, leading state wildlife officials to authorize the killing of up to four wolves.
Under the Washington state Wolf Management Plan, wolves will only be protected until there are 15 breeding pairs for three years.
So far, there are only three breeding pairs in the state.
Wielgus encourages people to partake in more non-lethal interventions such as getting more guard dogs, range riders on horseback, flags, spotlights and risk maps, which discourage grazing animals in hard-to-protect, wolf-rich areas.
However, he added, “The only way you’re going to completely eliminate livestock depredations is to get rid of all the wolves,” said Wielgus. “And society has told us that’s not going to happen.”
from The Big Science Blog http://ift.tt/1yjOT2Y
Shooting and trapping wolves won’t reduce the number of livestock-related deaths. But it will put wolves right back on the endangered species list, Washington State University researchers have found.
Wolves have moved south from protected lands on the U.S.-Canada border to repopulate the Washington Cascades. Pictured is a member of the Teanaway Pack, in the Cascades north of Cle Elum. A breeding female wolf from the pack was poached last month. Wildlife groups are offering a $15,000 reward. (Photo courtesy of Conservation Northwest).
When analyzing 25 years of data collected by the U.S. Fish and Wildlife Services Interagency in Montana, Wyoming, and Idaho, WSU wildlife biologist Rob Wielgus and data analyst Kaylie Peebles found that when a wolf is killed, the chances of livestock getting killed the following year increased – five to six percent for cattle and four percent for sheep.
For every 20 wolves killed, livestock deaths doubled. The researchers noticed that the trend didn’t reverse until 25 percent of wolves were killed.
“I had no idea what the results were going to be,” Wielgus said in a WSU press release. “However, I was surprised there was a big effect.”
Why shooting isn’t the solution
Wielgus isn’t completely sure why more livestock die when a smaller numbers of wolves are killed, but he does have a theory:
Wolf killings likely disrupt the social cohesion of the pack, he said. Packs are led by a male and female breeding pair. If one or both is killed, the pack can split up, increasing the number of breeding pairs and ultimately, the wolf population. Wielgus found that livestock loses decline only when enough wolves are killed because it overwhelms the wolves’ ability to keep up through reproduction.
However, Wielgus suggests that making a habit out of killing wolves is counter-productive. Either livestock losses go up or, if enough wolves are killed to reduce livestock deaths, the wolf population rate drops so low that they are right back on the endangered species list.
“It’s a bit of a catch-22,” Wielgus told National Geographic. “You can reduce them now, but you can only reduce them so far, and when you stop that heavy harvest, now you’re at maximum livestock depredation.”
History behind wolf killings
In the ranching world, shooting wolves has been a widely accepted practice. So much that it led to the animal’s eradication in the western U.S. in the 1930s. However, over the past 30 years, the wolf population has slowly grown from less than 300 to over 4,000.
Despite the resurgence of wolves in the mid-1990s, government officials and ranchers have relied on guns to cope with livestock problems – killing more than 2,000 wolves by 2013.
However, there have never been any large-scale studies showing whether killing wolves helps protect livestock.
Off the Endangered Species list
In 2011, wolves were removed from federal protection under the Endangered Species Act in Idaho, Montana, and parts of Washington, Oregon, and Utah. The result: making it easier to shoot them. (Wyoming was under the same verdict until a federal judge overturned the ruling this past September.)
Because of it, the wolf population in Montana and Idaho had surged to slightly more than 600 in each state, with 231 wolves killed in Montana and 356 in Idaho.
To make matters worse, Josh Bransford from Idaho made headlines for taking a photograph in front of a living wolf in a leg-hold trap surrounded by bloody snow in 2012.
As the picture went viral, the wolf debate escalated.
“If this is what passes as compliance with the Department of Fish and Game’s rules, there’s a serious problem with the adequacy of state regulation,” said Michael Robinson, a spokesman for the group in New Mexico, in a news release.
The Idaho legislature is not doing anything to help either. Last year, their state legislature created a Wolf Depredation Control Board to push wolf numbers to just above 150, a cutoff that could renew protection under the Endangered Species Act in that state.
Wolf problem in Washington
Washington has its own set of wolf problems. This past summer, wolves from the Huckleberry Pack in Stevens County killed more than 30 sheep, leading state wildlife officials to authorize the killing of up to four wolves.
Under the Washington state Wolf Management Plan, wolves will only be protected until there are 15 breeding pairs for three years.
So far, there are only three breeding pairs in the state.
Wielgus encourages people to partake in more non-lethal interventions such as getting more guard dogs, range riders on horseback, flags, spotlights and risk maps, which discourage grazing animals in hard-to-protect, wolf-rich areas.
However, he added, “The only way you’re going to completely eliminate livestock depredations is to get rid of all the wolves,” said Wielgus. “And society has told us that’s not going to happen.”
from The Big Science Blog http://ift.tt/1yjOT2Y
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