WASHINGTON (AP) – One spring afternoon in 2015, biologist Thomas Gable traced the GPS tracking collar signals from a gray wolf to a small creek in Minnesota Travel National Park, where he discovered a footprint of a dog leg in dust and wolf tufts and beaver skin stuck in low bramble.
A beaver had fallen victim to a wolf, Gable deduced. The ongoing paintings of industrial rodents remained nearby: clean poplar logs crossed the creek and a pond about 30 centimeters deep shaped them. the prey had begun to collapse. Without an aquatic engineer to fix the structure, the pond was gone.
“The water disappeared completely,” said Gable, who is founded at the University of Minnesota. But the episode sparked an idea.
Over the next 4 years, biologists placed GPS collars on about 30 wolves in the park; they then visited all the places where the wolves had stayed for more than 20 minutes and looked on the floor for clues about the animals they were feeding on. the moment beaver dams are abandoned nearby.
“Once a wolf is a beaver,” Gable said, “some other beaver takes some time to return to the site.
On the site of the deserted dam studied, it took more than a year for some other beaver to return, according to a study published Friday in the journal Science Advances.
Wolves that attack beavers deeply wetland ecosystems in northern Minnesota, as dams built through individual beavers, those unrelated to beaver colonies, quickly collapse. that have influenced the places where beavers have been able to build and maintain dams and ponds.
On average, there are about 73 wolves in the Travelers ecosystem, however, this number can range from 63 to 82, Gable said.
Research conducted in the winter of 2019-2020 through the Minnesota Department of Natural Resources revealed that the state was home to about 2,596 wolves.
Federal officials announced last month that the gray wolf would be removed from coverage of the U. S. Endangered Species Act. U. S. , leaving control decisions in the hands of states and opening the door to hunting in some. wolf hunting.
While wolf herds target giant animals such as deer and adult moose in winter, they tend to hunt alone in search of smaller prey, adding fawns and beavers, in summer.
Biologists call beavers “ecosystem engineers” because their prey creates wetlands and new habitats for plants, aquatic insects, amphibians, fish and birds.
“Beavers are so at the center of the appearance of those boreal forests that anything that affects beaver distribution will have a cascading effect,” said Rolf Peterson, a wildlife environmentalist at Michigan University of Technology who studies wolves in Michigan and is not interested in the new study. .
While Yellowstone and the neighboring western states are the best-known gray wolf houses in the United States, wolf herds are also found in the forests of Minnesota and Michigan, where they are combined with wolf populations in neighboring Canada.
Peterson contributed to which he revealed that beaver colonies at Royal Island National Park in Michigan increased five times between 2010 and 2018, when the wolf population declined.
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The Associated Press Department of Health and Science is supported by the Department of Scientific Education at Howard Hughes Medical Institute. The AP is for all content only.