https://www.google.com/url?rct=j&sa=t&url=https://phys.org/news/2019-02-black-population-years-safer-habitable.html&ct=ga&cd=CAEYAioTNDA2ODU3NjQ2MjUxMDMwMTYzNTIaNTZkMWU3ZjE5ZThmOTk5MTpjb206ZW46VVM&usg=AFQjCNF56ZrYSErtjE251LE61ooDjK2E2Q
A new study by University of Alberta biologists shows black bear populations are lowest on Crown land and most dense on national park land, followed by private land, highlighting issues for management and conservation efforts.
Scientists analyzed black bear DNA, collected from hair samples left behind after the bears rub against objects like trees and power poles, to identify individuals and get an estimate of overall populations on public and private land. Credit: Ryan Peruniak
The 3,600 km2 study area is in the southern Canadian Rocky Mountains and is bounded by Highway 3 to the north, British Columbia to the west, the United States–Canada border to the south, and Highway 2 to the east (Figure 1). The area includes WLNP, which borders Glacier National Park (GNP), USA. The area is a mix of land‐cover types: conifer forest (29%), agricultural (22%), native grassland and cultivated fields (16%), shrubland (16%), and deciduous forest (11%). Agriculture is the primary industry (Statistics Canada, MD of Pincher Creek, 2011 Community Profile).
First study of black bear population in 30 years identifies need for safer, habitable public land in Alberta
February 7, 2019 by Katie Willis, University of Alberta
A new study by University of Alberta biologists shows black bear populations are lowest on Crown land and most dense on national park land, followed by private land, highlighting issues for management and conservation efforts.
Scientists analyzed black bear DNA, collected from hair samples left behind after the bears rub against objects like trees and power poles, to identify individuals and get an estimate of overall populations on public and private land. Credit: Ryan Peruniak
The 3,600 km2 study area is in the southern Canadian Rocky Mountains and is bounded by Highway 3 to the north, British Columbia to the west, the United States–Canada border to the south, and Highway 2 to the east (Figure 1). The area includes WLNP, which borders Glacier National Park (GNP), USA. The area is a mix of land‐cover types: conifer forest (29%), agricultural (22%), native grassland and cultivated fields (16%), shrubland (16%), and deciduous forest (11%). Agriculture is the primary industry (Statistics Canada, MD of Pincher Creek, 2011 Community Profile).
"We might have thought that Crown land would host more black bears," said ecologist Mark Boyce. "However, many bears appear to have been displaced onto private lands, likely due to excessive use of Crown land for recreation, like quadding, camping and motorbiking."
In the study—the first comprehensive analysis of the black bear population in Alberta in more than 30 years—researchers used bear hair samples collected from trees, power poles and fences to identify individuals by DNA and then estimate population size.
"There are a number of possible reasons why density differs by land tenure, such as mortality risk from humans and the availability of foods," said Annie Loosen, who recently completed her master's degree under Boyce's supervision.
"There are a number of possible reasons why density differs by land tenure, such as mortality risk from humans and the availability of foods," said Annie Loosen, who recently completed her master's degree under Boyce's supervision.
Surface densities derived from top‐performing male and female black bear spatially explicit capture–recapture models in southwestern Alberta (2013–2014)
"Private lands in our study are mainly agricultural lands, which can also be attractive to black bears, especially stored and standing grain," she added.
"In Alberta, this is particularly problematic because landowners can hunt or give other hunters permission to shoot a black bear on their land at any time of year without restriction."
Supporting policy
The findings support recent decisions limiting off-highway vehicle use in Castle Provincial Park and Castle Wildland Provincial Park, explained Boyce.
Harvest density (individuals/1,000 km2) for male and female black bears the year prior to non‐invasive genetic sampling in southwestern Alberta (2013–2014). Wildlife management unit (WMU) 400 is on Crown land and WMU 303 and 302 are on private land
"Our results reinforce the decision to protect core habitats in provincial parks. We are keen to learn the response by both grizzly bears and black bears to increased protection on Crown land."
The researchers also recommended ongoing monitoring of black bear populations to document the outcomes of policy changes.
The study, "Land Tenure Shapes Black Bear Density and Abundance on a Multi‐use Landscape," was published in Ecology and Evolution.
More information: Anne E. Loosen et al. Land tenure shapes black bear density and abundance on a multi-use landscape, Ecology and Evolution (2018). DOI: 10.1002/ece3.4617
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