To protect the vulnerable biodiversity of the Arctic, researchers from the University of Alberta and San Diego Zoo Wildlife Alliance (SDZWA) have identified a new conservation strategy in western Hudson Bay: using polar bears as an "umbrella species" to guide where protection is needed most.

Establishing boundaries for marine protection is often difficult due to a lack of data on where marine life gathers. Polar bears offer a solution: by analyzing two decades of tracking data from 355 bears, a new study in Arctic Science identified a “high-use” area near Cape Churchill, Manitoba, highlighting it as a prime location for a Marine Protected Area (MPA).

According to the study’s authors, including U of A biological sciences professor Dr. Andrew Derocher and Dr. Nicholas Pilfold, conservation scientist at SDZWA, protecting polar bear habitat naturally safeguards the resources they rely on to survive. In turn, polar bears provide critical benefits to the ecosystem; for example, their leftover kills feed scavengers like Arctic foxes, wolves, ravens, and gulls. The research shows polar bears meet nearly all the criteria for an umbrella species, including well-documented biology, vast home ranges, and a high sensitivity to human disturbance.

Last month Manitoba Premier Wab Kinew announced funding to explore the establishment of a national marine conservation area in western Hudson Bay.

“By leveraging the extensive data we have on polar bears, we can help design MPAs that safeguard both the bears and the vast network of Arctic species that rely on them,” says Dr. Pilfold. “Well-designed dynamic MPAs have the potential to preserve biodiversity in a constantly changing Arctic landscape.”

The authors acknowledge climate change and melting ice may eventually reduce the polar bear’s habitat, but using the northern bear as an umbrella species can provide a good starting point.

"In the rapidly warming Arctic, marine ecosystems will be stressed by the additive effects of industrial activity and polar bear location data provide a path to designing marine protected areas," says Dr. Derocher.

Sunday, March 15, 2026

Ravens don’t follow wolves to dinner – they remember where the food is

Summary author: Walter Beckwith

Peer-Reviewed Publication

American Association for the Advancement of Science (AAAS)

New findings challenge the long-held idea that scavengers seeking food routinely follow predators to find it. Studying common raven, gray wolf, and cougar in Yellowstone National Park, researchers found that ravens rarely trail predators over long distances; instead, they rely on spatial memory to return to places where kills have occurred before. Scavenger species that rely on the kills of predators face the challenge of finding food that is patchily distributed, unpredictable, and often ephemeral because many animals compete for it. A widely accepted hypothesis suggests that scavengers solve this problem by adjusting their movements to follow large carnivores to their kills. Although scavengers are frequently observed near carnivores in the field, it’s unclear whether following behavior reflects the dominant foraging strategy. However, this hypothesis has been difficult to evaluate due to the challenge of simultaneously tracking predators and scavengers across large distances.

Matthias-Claudio Loretto and colleagues investigated how common raven locate carrion by studying their interactions with grey wolf and cougar in Yellowstone National Park. Ravens are often seen traveling with wolves and rapidly gathering at fresh kills. Loretto and colleagues hypothesized ravens may rely on memory and prediction to revisit areas where predators frequently make kills, rather than following them in real time. Loretto et al. used GPS devices to track the movements of ravens, wolves, and cougars over 2.5 years, as well as records of hundreds of wolf and cougar kills. Contrary to longstanding assumptions, the authors found that long-distance predator following was rare. Instead, ravens repeatedly returned, sometimes from distances of up to 155 kilometers, to areas where wolf kills were common. Raven-cougar interactions were rare. The findings indicate that ravens rely on spatial memory, treating areas with historically high kill density as predictable foraging sites. According to the authors, this suggests that navigation and memory, rather than real-time tracking of predators, play the dominant role in how ravens locate food sources.

Podcast: A segment of Science's weekly podcast with Matthias-Claudio Loretto, related to this research, will be available on the Science.org podcast landing page after the embargo lifts. Reporters are free to make use of the segments for broadcast purposes and/or quote from them – with appropriate attribution (i.e., cite "Science podcast"). Please note that the file itself should not be posted to any other Web site.

Journal

Science

DOI

10.1126/science.adz9467