All African Carnivores Risk Losing Their Range

From a mongoose to a weasel, all carnivores in Africa could lose at least part of their home ranges, a new study finds.

The International Union for Conservation of Nature (IUCN) Red List tracks the status of the world’s species. Assessors place species into a category of risk, based on criteria that show how close they are to extinction.

The category of “least concern” covers species that don’t qualify as critically endangered, endangered, vulnerable, or near threatened. But this new study suggests that even those species likely face serious risks.

Yale University scientists assessed 91 African carnivores and found locations in each species’ range that are at risk of getting smaller. It’s important to know changes in habitat or range in order to make plans to save a species.

“Species distribution or range maps are critically important for conservation efforts, but that are lacking in context to actually inform decisions and prioritization,” study author Nyeema C. Harris, Yale associate professor of wildlife and land conservation, tells Treehugger.

“We wanted to present a strategy that could improve our understanding of which areas in a species' range, which highlights particular populations that could be most vulnerable.”

The results were published in the journal Proceedings of the National Academy of Sciences (PNAS).

All Carnivores Affected

Africa is home to a third of the world’s carnivore species. The land is filled with threats to species survival including droughts, as well as pressures from urbanization and agriculture. The area is rich in biodiversity with conservation efforts designed to protect species.

For their study, researchers created a model to study projected range loss for African carnivores.

“​We took a geospatial approach by aggregating relevant threat layers such as the distribution of drought risks and human modification and overlaid with assets (or resources) such as protected areas and cultural diversity that could potentially thwart threats,” Harris explains.

“This simple, but powerful approach identified areas across a species' range at risk of contraction based on having more threats than assets, creating a possible deficit in what you called available conservation capacity.”

She says the most important finding of their work is that all the species they studied have at least part of their range at risk of growing smaller, with an average of 15% of their ranges at risk. They found, for example, that the common slender mongoose (Herpestes sanguineus) has 16% of its range at risk of loss, while the Egyptian weasel (Mustela subpalmata) faces threats to 70% of its range.

They found that some carnivores listed as endangered by the IUCN had a wide range of differences in how much their ranges were at risk. The Ethiopian wolf (Canis simensis) had 33% of its range at risk of shrinking, while the African wild dog (Lycaon pictus) only had 3% of its range facing loss.

Harris says it was interesting that even species not considered endangered or threatened still risk habitat loss.

“It was surprising, especially since only a handful of charismatic African carnivores get the ‘lion's share' of conservation attention and dollars,” she says. “Our findings not only demonstrate another approach to assessing risks from range contractions, but also that African carnivores big and small warrant conservation concern.”

She says their model will be used to assess carnivores around the world, and she hopes that other researchers will use similar methods to study other groups, such as primates and amphibians.

“Our work was narrowly focused on African carnivores, but the approach we applied to assess available conservation capacity in a spatially explicit manner could be applied to other geographies and taxa to present a more holistic picture,” Harris says. 

“In our chosen system, we now have areas throughout each African carnivore range where extirpation may occur. Thus, our work can help prioritize targeted conservation efforts in those areas as well as guide the socio-ecological research necessary to make such efforts inclusive, effective, and sustainable.”