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Through a combination of increased permits, more times to
hunt and additional hunting areas, Utah wildlife managers
believe they can reduce human-bear conflicts.
"We want to come in and make a separate recommendation
if the changes were too aggressive," McFarlane told the
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Handling denning bears may become less common as the DWR continues a research project designed to give wildlife managers a better idea of just how many black bears call Utah home. Ask them now for an estimate of Utah's black bear population and you get something like "3,000, plus or minus 1,000." "That's essentially the million dollar question," said Justin Dolling, mammals coordinator for the DWR.
According to the DWR's Utah Black Bear Management Plan, biologists make an educated guess about the bear population based on several factors: monitoring bears known to have been killed each year through hunting; counting bears removed as nuisance animals and killed in auto accidents; and by the sex ratio and age structure of animals taken during hunts.
Hunting permits have historically been based on the percentage of females taken by hunters in each unit the previous year.
"We want to maintain less than 40 percent of females in the harvest," said Dolling. "If we have 32 percent, it suggests we have room for more permits. If we have 45 percent, then we back off. Having some better numbers will really help the recommendation process."
Jordan Pederson, who spent a lot of time during his years with the DWR crawling into bear dens, has often wondered if there was a better way to monitor the bear population. He had heard about a DNA population study of grizzly bears at Whistler Resort in British Columbia and suggested DWR launch a comparable study on Utah's black bears.
"Similar previous studies involved many, many people and cost millions of dollars," said Pederson, who is now retired. "It was our premise that we could do the same study on a manageable scale and still provide meaningful results."
As an advocate for responsible predator management, Kirk Robinson is glad to see the state wildlife agency try to get more accurate numbers on the bear population.
"I have some difficulty with studies that require capture of animals, sedating them, fitting them with collars etc.," said Robinson, of the Western Wildlife Conservancy, a Utah-based group focused on protecting large carnivores like mountain lions and bears. "I believe that it is often justified in today's world, but I also believe that it is generally not very good for the animals on which it is inflicted."
Hair of the bear » In the summer of 2004, Pederson set about collecting hair samples from bears in a 100 square-mile area east of Kamas in the Uinta Mountains. He hoped the study would help determine more precisely how many bears were in a given area in a way that was less disruptive than denning and more accurate than extrapolating from hunting success.
Pederson sought help from the High Uinta Chapter of Back Country Horsemen of America. "What was supposed to be a one-year project ran into five years," Pederson said. "They volunteered everything from their time to the cost of gas. It was an amazing contribution."
Amazing to the tune of more than 4,720 volunteer hours and 19,144 miles of riding. The first job was building the 16 stations where hair would be collected. Logs were stacked as if for a bonfire and a piece of carpet was hung near the top. The carpet had been soaked in such bear delights as fish oil, rotting flesh and cattle blood. There was no food reward for bears, only the enticing aromas. Part of the study was determining which scent worked best to draw bears; anise oil, a plant extract which resembles licorice, was most popular, followed closely by fish oil.
The scent pile was surrounded by a single strand of barbed-wire strung 20 inches off the ground. When bears, or other animals curious about the smell, cross over or under the barbed-wire, they leave a hair sample. Pederson collected 579 samples from 2004 through 2007. Another 139 collected in 2008 are still being analyzed by a private DNA lab in Canada.
Thirty-four individual black bears (19 males and 15 females) were found in the 100-square mile area, a number Pederson said was higher than he expected. But during all the hours spent riding to and from the stations, Pederson and the volunteers only spotted one bear, which demonstrates how elusive they can be. The study also showed that bears will stay put if they have enough food sources.
"Precipitation dictated movement patterns," Pederson said. "On dry years, they moved a lot from station to station. On wet years, there was very little movement."
Given the success of the Kamas research, Utah wildlife officials will gather similar information in the state's four other geographical regions this summer and plan to run the studies concurrently in all five regions in 2011, 2014 and 2017.
"Wildlife managers in each of the regions are excited to get the study going in their area," Pederson said. "Getting a better idea of the base number of bears gives us much more confidence when we make recommendations for permit numbers and future habitat projects."
Wildlife managers
approve
plan to kill more
bears in Utah
First Published 6 hours ago • Updated 3 hours ago
Hunting » Increased permits, more
hunting times, areas could help reduce
hunting times, areas could help reduce
bear-human conflicts.
A troubling number of black bears were
killed by federal and state wildlife managers
killed by federal and state wildlife managers
in 2014
after they destroyed crops, feasted on
livestock or threatened people.
livestock or threatened people.
Utah Division of Wildlife Resources (DWR)
leaders hope changes to the
leaders hope changes to the
bear hunt approved
by the Utah Wildlife Board Tuesday could
lead to rank-and-file hunters
lead to rank-and-file hunters
killing more black
bears — perhaps an additional 70 to 90
animals each year — and cutting the number
animals each year — and cutting the number
that have to be removed by other means.
barbed wire used to obtain hair samples from Black Bears
Through a combination of increased permits, more times to
hunt and additional hunting areas, Utah wildlife managers
believe they can reduce human-bear conflicts.
Most years, approximately 230 to 270 bears are killed by
hunters. Biologists expect somewhere between 300 and
320 bears to be killed under the new hunts and rules.
hunters. Biologists expect somewhere between 300 and
320 bears to be killed under the new hunts and rules.
Biologists believe Utah’s black bear population has doubled
over the past 15 years to an estimated 4,100 animals. DWR
mammals program coordinator Leslie McFarlane said the
population appears to be growing by 5 to 6 percent annually.
over the past 15 years to an estimated 4,100 animals. DWR
mammals program coordinator Leslie McFarlane said the
population appears to be growing by 5 to 6 percent annually.
McFarlane asked the board for the chance to make changes
in the number of bear-hunting permits after a year, rather
than waiting for several years as the plan dictates.
in the number of bear-hunting permits after a year, rather
than waiting for several years as the plan dictates.
"We want to come in and make a separate recommendation
if the changes were too aggressive," McFarlane told the
Some Utahns at Tuesday’s meeting spoke against the bear
hunt and using dogs and bait.
hunt and using dogs and bait.
"The problem is not the bears," said Danielle Patterson,
who described herself as an environmental studies major.
"The problem is more about people. We need more
education about how people can live with bears."
who described herself as an environmental studies major.
"The problem is more about people. We need more
education about how people can live with bears."
Sheehan and McFarlane said efforts to educate the
public about black bears continue — both on the state
and federal level. More information is available at
www.wildawareutah.org.
public about black bears continue — both on the state
and federal level. More information is available at
www.wildawareutah.org.
Bear market: Biologists want to know how many bears live in Utah
Published July 2, 2009 3:18 pm
Study seeks a better count by using hair sample
Handling denning bears may become less common as the DWR continues a research project designed to give wildlife managers a better idea of just how many black bears call Utah home. Ask them now for an estimate of Utah's black bear population and you get something like "3,000, plus or minus 1,000." "That's essentially the million dollar question," said Justin Dolling, mammals coordinator for the DWR.
According to the DWR's Utah Black Bear Management Plan, biologists make an educated guess about the bear population based on several factors: monitoring bears known to have been killed each year through hunting; counting bears removed as nuisance animals and killed in auto accidents; and by the sex ratio and age structure of animals taken during hunts.
Hunting permits have historically been based on the percentage of females taken by hunters in each unit the previous year.
"We want to maintain less than 40 percent of females in the harvest," said Dolling. "If we have 32 percent, it suggests we have room for more permits. If we have 45 percent, then we back off. Having some better numbers will really help the recommendation process."
Jordan Pederson, who spent a lot of time during his years with the DWR crawling into bear dens, has often wondered if there was a better way to monitor the bear population. He had heard about a DNA population study of grizzly bears at Whistler Resort in British Columbia and suggested DWR launch a comparable study on Utah's black bears.
"Similar previous studies involved many, many people and cost millions of dollars," said Pederson, who is now retired. "It was our premise that we could do the same study on a manageable scale and still provide meaningful results."
As an advocate for responsible predator management, Kirk Robinson is glad to see the state wildlife agency try to get more accurate numbers on the bear population.
"I have some difficulty with studies that require capture of animals, sedating them, fitting them with collars etc.," said Robinson, of the Western Wildlife Conservancy, a Utah-based group focused on protecting large carnivores like mountain lions and bears. "I believe that it is often justified in today's world, but I also believe that it is generally not very good for the animals on which it is inflicted."
Hair of the bear » In the summer of 2004, Pederson set about collecting hair samples from bears in a 100 square-mile area east of Kamas in the Uinta Mountains. He hoped the study would help determine more precisely how many bears were in a given area in a way that was less disruptive than denning and more accurate than extrapolating from hunting success.
Pederson sought help from the High Uinta Chapter of Back Country Horsemen of America. "What was supposed to be a one-year project ran into five years," Pederson said. "They volunteered everything from their time to the cost of gas. It was an amazing contribution."
Amazing to the tune of more than 4,720 volunteer hours and 19,144 miles of riding. The first job was building the 16 stations where hair would be collected. Logs were stacked as if for a bonfire and a piece of carpet was hung near the top. The carpet had been soaked in such bear delights as fish oil, rotting flesh and cattle blood. There was no food reward for bears, only the enticing aromas. Part of the study was determining which scent worked best to draw bears; anise oil, a plant extract which resembles licorice, was most popular, followed closely by fish oil.
The scent pile was surrounded by a single strand of barbed-wire strung 20 inches off the ground. When bears, or other animals curious about the smell, cross over or under the barbed-wire, they leave a hair sample. Pederson collected 579 samples from 2004 through 2007. Another 139 collected in 2008 are still being analyzed by a private DNA lab in Canada.
Thirty-four individual black bears (19 males and 15 females) were found in the 100-square mile area, a number Pederson said was higher than he expected. But during all the hours spent riding to and from the stations, Pederson and the volunteers only spotted one bear, which demonstrates how elusive they can be. The study also showed that bears will stay put if they have enough food sources.
"Precipitation dictated movement patterns," Pederson said. "On dry years, they moved a lot from station to station. On wet years, there was very little movement."
Given the success of the Kamas research, Utah wildlife officials will gather similar information in the state's four other geographical regions this summer and plan to run the studies concurrently in all five regions in 2011, 2014 and 2017.
"Wildlife managers in each of the regions are excited to get the study going in their area," Pederson said. "Getting a better idea of the base number of bears gives us much more confidence when we make recommendations for permit numbers and future habitat projects."
Source: Utah Division of Wildlife Resources
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A robust-design analysis to estimate American black bear population parameters in Utah(2005-2010)
Utah Division of Wildlife Resources, PO Box 968, Kamas, UT 84036, USA
Utah Division of Wildlife Resources, 1594 W North Temple, Salt Lake City, UT 84114, USA
Department of Wildland Resources, Utah State University, Logan, UT 84322-5230, USA
Colorado Parks and Wildlife, 6060 Broadway, Denver, CO 80216, USA
Abstract
We evaluated the efficiency of an extension of a single season capture–mark–recapture (CMR) population estimation method, a closed-capture robust-design model, to monitor trends in population size, apparent survival, and temporary emigration rates over a 5-year period for a low-density population of American black bears (Ursus americanus) in north central Utah, USA. We also used robust-design Pradel models to estimate finite rate of population change and recruitment. We identified individual bears through genetic analysis of tissue samples collected non-invasively at scent-lured sampling sites. .
Population size appeared to be stable or slightly increasing over the 5-year period. This noninvasive CMR study provided relatively efficient, precise estimates of a low-density black bear population on a small study site. We recommend using robust-design closed-capture models if samples are taken over multiple years; in addition to population size, apparent survival, movement, recruitment, and finite population change can be estimated, providing timely insights into population trends and the mechanisms driving them.
Received: October 28, 2010;
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