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Regional bear study underway

Go west on U.S. 160, cross the Piedra River, drive over Yellow Jacket Pass. Take a right on Beaver Meadows Road.

Go to the end of the pavement, and don’t stop going.

Drive until the road ends.

This is wildland — prime habitat for the black bear in southwestern Colorado.

This is where the wildland grid is placed for one of the most comprehensive studies to date on bear-human conflicts and the ecology of urban and wildland bears.

This is a research site for a study on black bears: “Black bear exploitation of urban environments: finding management solutions and assessing regional population effects.”

After getting out of the vehicle, take a trail, then go by memory, or GPS, to the location of the snare, the bear hair snare. Depending on the type of bait used, a person can trust their nose to lead them on the last legs of their journey to the snare.

Once the snare is found, the inspection begins. Has the snare been able to capture something of the wild? Will it help us understand the ways and population of the black bear? Will it help create more effective management strategies to reduce bear-human conflict?

That is what mammal researcher for the Colorado Division of Parks and Wildlife Heather Johnson is hoping it will do.

Bear-human conflicts are expected to rise in the future, due partially to anticipated development of human communities and changing climate patterns, altering where bears, ever-opportunistic foragers, find their food source.

The study has three objectives: 1) test management strategies to reduce bear-human conflicts; 2) determine the influence of urban environments on regional bear population dynamics; and 3) develop population and habitat models to support the sustainable management of black bears in Colorado.

Johnson explained that not as much population data has been collected on bears as on other mammals, such as ungulates; and she would know, because most of her previous studies have focused on ungulates such as deer, elk and ram. The reasons, Johnson explained, for the more readily available population and habit data for ungulates as opposed to bears is simple: ungulates are easier mammals to collect data on.

Consider the following: ungulates are herd animals. They don’t hibernate. During the winter, while researchers count and observe the herd, the animals can easily be spotted from a helicopter. If there is a need to collect scat, the animals produce enough visible scat for sampling.

A bear, on the other hand, does not make the task so easy.

Bears hibernate in winter, which is the easiest season for spotting wildlife. They do not run in herds, but instead tend to be solitary animals. In the summer, from a helicopter’s height, bears are often concealed by vegetation. Finding a bear’s scat has proven to be so difficult for researchers that people train scat detection dogs — dogs specifically trained to find a specific type of mammal scat.

This study, however, is not calling for the dogs to be let out just yet. In the second summer of this study, bears are being outfitted with GPS collars that send Johnson e-mail updates throughout the day, informing her of the bear’s location. Johnson explained that advances in technology, in particular in the field of wildlife statistics, offer new ways to monitor bear populations and collect much-needed data.

One such advancement in data collection being used is the hair snare, and this study calls for 70 bear hair snares, 35 set up on a grid over Durango, 35 set up in a grid over the Piedra area. The study uses the city of Durango as the urban density grid and the Piedra wilderness area as the wildland density grid.

The hair snare, Johnson said, works with a mark-recapture technique. The snare is set up by placing barbed wire around an area. Inside the area, there is a baited scents station using the scents of bacon, strawberry, anise and fish. The wire is at a height that bears can crawl under or over. As the bear does so, a barb will collect a sample of the bear’s hair. This hair, Johnson continued, will be collected, then sent off to Wildlife Genetics International laboratory in Canada. From all the viable hair samples, the laboratory will extract hundreds of bear genotypes. The genotype data will be used to estimate density using a population model.

Currently, wildlife management agencies, such as the Colorado Division of Parks and Wildlife, use management strategies such as removing anthropogenic food source, translocation suitability modeling and alteration of public hunting programs to reduce human-bear conflict. However, all three strategies have never been through rigorous testing to verify their efficacy.

While this study does not test the management strategies, it will, instead, as stated in the study plan, “elucidate the dynamics of bear populations along the wildland-urban interface,” in order to, “sustainably manage bear populations in the face of a growing human population and changing landscape conditions.”

The results of the study will be used in creating techniques for managing black bears in Colorado. This is a collaborative study with the following entities taking part: Colorado Division of Wildlife, the Wildlife Conversation Society, Colorado State University, National Wildlife Research Center and Bear Trust International.

lindsey@pagosasun.com

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