UW, other researchers find concerns for animals linked to same habitats | News
January 11, 2022
Many animals display strong loyalty to the site, including these (clockwise from top left): Adélie penguins, mule deer, great gray owls, sockeye salmon and northern elephant seals. (Daniel Costa, Jonathan Armstrong and Amanda Hancock Photos)
Some wild animals are stuck in their tracks. Like humans, wild animals often return to the same places to eat, walk the same paths to travel, and use the same places to raise their young.
A team of researchers led by scientists from the University of Wyoming and the University of Washington reviewed the scientific literature and found that while this “consistent” behavior can be beneficial when environmental conditions do not change very quickly , these benefits may not be realized in the ever-changing world dominated by humans. The research was published today (Tuesday) in the scientific journal Frontiers in ecology and environment.
Environmentalists use the term “site loyalty” to describe the behavior of animals stuck in their habits. Site fidelity is the tendency to return to previously visited places and is common to many species, from fish and birds to mammals and insects. Think of the salmon returning to their native streams to spawn, or the birds that return year after year to the same nesting site – site fidelity is all around us in nature.
As animals become more familiar with a place, site loyalty can help them know where to find good food or hiding places from predators, and can help them move efficiently to and from those resources. However, the authors discovered an emerging theme in the scientific literature.
“Animals that have a strong loyalty to the site find it difficult to adapt to the new landscapes that appear around them because of humans,” says Jerod Merkle, assistant professor at the University of Wyoming and co-lead author of the paper.
The article’s broader message suggests that, when faced with human disturbance or climate change, animals with high site fidelity may not survive or reproduce as well as animals with more behaves. flexible. When populations consist of large numbers of individuals loyal to the site, this can lead to population declines.
In Wyoming, for example, large deposits of natural gas have been developed in several mule deer wintering grounds. While mule deer can make small changes to their range to avoid infrastructure, they stay true to the same general area rather than abandon it altogether. Their continued use of these degraded areas after development can have negative consequences. In a long-term study, the researchers found a 40% drop in the mule deer population as a result of large-scale energy development in their wintering grounds.
This is also playing out because of climate change. In female northern elephant seals in the Pacific Ocean, loyalty to the site is a winning strategy under normal climatic conditions. In typical years, site-loyal seals are better able to find food and grow fat than their more flexible counterparts. But, when abnormal climatic conditions such as extreme El Niños cause great changes in the ocean ecosystem, seals with flexible behavior become the winners, and female seals with strong site fidelity are unable to win. as much precious fat as they need to reproduce.
“Although each of us was working on very different species from each other, our group came together because we all recognized that there was a clear link between high site fidelity and species decline.” says Briana Abrahms, assistant professor at the University of Washington and the other co-lead author. “We all thought it was important to draw attention to this link for other wildlife researchers and managers. Recognizing the types of species or behaviors that may be most affected by human-induced environmental changes can help develop conservation priorities and actions.
While the authors’ synthesis provides a grim sketch of the future of high-fidelity species at the site, they also provide a result.
“While these species seem to be stuck in their ways, many of them also have unique but subtle ways of dealing with change,” says Jonathan Armstrong, assistant professor at Oregon State University and co-author of the study.
Every once in a while an animal does something new and it works. Although such cases are rare, these “innovators” may be the key to persistence in changing landscapes.
“We just have to be patient and make sure populations don’t collapse before such innovators show up,” Armstrong said.
The authors conclude with a number of suggestions for researchers and practitioners. First, long-term monitoring is essential to see how individuals and populations respond to change. Second, they suggest that biologists shouldn’t expect animals to always use and find the best habitats. This is particularly important for restoring new areas of habitat, which may not work very well for species very loyal to the site, as they may not “find” these restored habitats.
For this reason, the authors third suggest that conservation of species with high site fidelity focuses on the protection and restoration of heavily used sites, rather than off-site mitigation.
The other authors of the article are Hall Sawyer, of Western EcoSystems Technology Inc. in Laramie; Daniel Costa, University of California-Santa Cruz; and Anna Chalfoun, of the Wyoming Cooperative Fish and Wildlife Research Unit at the University of Wyoming.