New study highlights importance of water resources for Andean bears

San Diego Zoo Global

A new study is shedding light on the importance of one critical resource for Andean bears living in the dry mountain forests of Peru: water. The study--a collaboration between the Norwegian University of Life Sciences and San Diego Zoo Global, with assistance from the Spectacled Bear Conservation Society-Peru--found that Andean bears focus much of their tree-rubbing behavior on shrubs and trees that are located on trails near water holes. Bears typically bite, claw and rub their body parts on trees, which is believed to be an important form of communication with other bears in the region. The discovery that this behavior occurs near water holes could have implications for future conservation programs. "It may seem obvious that water holes would be an important resource for Andean bears living in tropical dry forests--however, these results suggest that water holes are significant not just as sources of drinking water, but also as important sites where bears communicate with one another," said Russ Van Horn, Ph.D., San Diego Zoo Global scientist. "Because water holes are often the focus of activity by humans and their livestock, conservation planners will need to balance the interests of people and Andean bears in future programs."
A paper detailing results of the study, recently published in the journal Ursus, reported that while Andean bears didn't show a particular preference for tree-rubbing species, the locations of rubbed trees and shrubs were concentrated on trails near water holes. In the tropical dry forests of Peru, water is a relatively rare, albeit critical resource. Consequently, since livestock in the area also make use of water resources, conflicts may result between humans and bears.
This study is part of a larger effort by San Diego Zoo Global researchers and local partners to better understand Andean bear behavior and ecology. Andean bears are considered an umbrella species in the region, meaning that conservation programs aimed at protecting Andean bears will indirectly benefit other species in the Andes Mountains.
Andean bears are listed as Vulnerable on the International Union for Conservation of Nature's (IUCN) Red List of Threatened Species. They are native to the Andean countries of South America, and are sometimes known as spectacled bears because of white or light fur around their eyes. San Diego Zoo Global has been working with local partners to research and protect Andean bears in Peru. Andean bear habitat is being lost at a rate of about 2 to 4 percent per year as it is destroyed for mining operations, farming and timber harvest. The construction of new roads also fragments bear habitat. In addition, climate change is altering the bear's habitat in unpredictable ways. Andean bears now primarily live in dense mountain forests, making the species difficult to study. The dry tropical forest where this study occurred is more open than other kinds of Peruvian forests, making field research easier.

'Outdated' management plan increases risks to Alaska's large carnivores

Oregon State University

IMAGE: Alaskan brown bears on Kodiak Island. view more 

Credit: Lisa Hupp, US Fish and Wildlife Service

CORVALLIS, Ore. - Alaskan wildlife management that prioritizes reducing bear and wolf populations so hunters can kill more moose, caribou and deer is both backward and lacks scientific monitoring, ecologists say in a paper published today in PLOS Biology.
Paring populations of large carnivores not only fails to meet the goal of creating a "hunting paradise" but may also interfere with important ecosystem services that predators atop the food chain provide, the scientists assert.
"Gray wolves, brown bears and black bears are managed in most of Alaska in ways designed to significantly lower their numbers," said study co-author William Ripple, distinguished professor of ecology in the Oregon State University College of Forestry. "Alaska is unique in the world because these management priorities are both widespread and legally mandated."
The paper notes that favoritism toward moose, caribou and deer over large carnivores acquired legal backing in Alaska with the 1994 passage of the state's Intensive Management Law. The legislation effectively calls for cutbacks in big carnivores to increase how many hoofed game animals are taken by humans.
"The law does also identify habitat management as a form of intensive management, but habitat management hasn't been used effectively as a tool to increase abundance of these ungulates," said corresponding author Sterling Miller, a retired research biologist with the Alaska Department of Fish and Game. "Therefore, the default tool is predator control, the most widespread form of which is liberalizing state hunting and trapping regulations for large carnivores. This liberalization has been most extreme for brown bears, as this species used to be managed very conservatively."
The paper points out that reported kills of brown bears by hunters have more than doubled over the past three decades and that since 1980 regulations intended to reduce predators have been in effect even in Alaska's 11 national preserves, which are managed by the National Park Service.
"Since 2000, state wildlife managers have done no studies to determine trends in brown bear populations anywhere in Alaska where intensive management for moose and caribou is ongoing and harvests of brown bears have, correspondingly, increased," Miller said. "Basically, managers have liberalized regulations for large carnivores in a strategy of 'kill as many as possible and hope that it is OK in the end.' This is not science-based management."
The authors stress that brown bears have the lowest reproductive rates of any large mammal in North America and are particularly susceptible to overharvest, and that the Alaskan government is the only wildlife-managing entity in the world whose goal is to reduce bear abundance.
"There are some places in Alberta, Canada, where wolves are being managed to reduce their abundance in the hope of keeping very small populations of woodland caribou from going extinct," Miller said. "This is different because the objective of that management is a conservation objective and not an objective of middle-class people putting more wrapped packages of moose meat in their freezers."
State and federal priorities for "subsistence hunting" are also somewhat problematic but only where they allow for harvests that aren't really of a subsistence nature, the authors say.
"It is also worth noting that subsistence hunting occurs in most Alaska national parks and monuments as mandated by the 1980 Alaska National Interest Lands Conservation Act, known as ANILCA," Miller said. "The act also mandates that Alaska national preserves are open to hunting and doesn't have a restriction on it being limited to subsistence hunting."
Many of the preserves are adjacent to national parks and both the parks and preserves were created by ANILCA. But with the loosening of hunting regulations for large carnivores in Alaska, the same more-lax regulations largely apply to the preserves as well, meaning predator control is occurring there too.
"Science-based management of large carnivores in most of Alaska will require the political will and wisdom to repeal Alaska's Intensive Management Law," the paper states. "Alternatively or additionally, it will require professional wildlife managers to resist adoption of predator reduction regulations that are not conducted as experiments and/or do not include adequate monitoring programs of both carnivores and ungulates."
Co-authoring the paper with Ripple and Miller were John Schoen, who is retired from the Alaska Department of Fish and Game, and Sanford Rabinowitch, who is retired from the National Park Service.
Additional information on trends in brown bear hunting regulations and harvests in Alaska is available in a 2017 paper by some of the same authors as the PLOS Biology article.