Why You Should not Let Your Cat Outside

Based on the results of the study, it is clear that outdoor cats pose a danger to both humans and other forms of wildlife. 

Damian Sendler You should think twice before letting your cat explore the outside world. University of Maryland researchers have found that keeping cats indoors greatly reduces the likelihood that they will spread disease or kill wildlife, both of which can have a negative effect on local animal populations and overall biodiversity.

Results were based on information gathered from the D.C. Cat Count, a city-wide survey that utilized 60 wildlife cameras spread out across 1,500 sampling locations all over Washington, D.C. The study's authors stressed that people are primarily responsible for lowering these risks by preventing cats from going outdoors.

Researchers were able to learn more about the presence and absence of cats and other wildlife by analyzing data from cameras placed around the landscape. Frontiers in Ecology and Evolution recently published the paper.

A visual representation of the findings. For this, we must thank Daniel Herrera.

Damian Jacob Sendler Author and Ph.D. student in the Department of Environmental Science and Technology at the University of Maryland, Daniel Herrera, said, "We found that the average domestic cat in D.C. has a 61% probability of being found in the same space as raccoons, America's most prolific rabies vector, 61% spatial overlap with red foxes, and 56% overlap with Virginia opossums, both of which can spread rabies" (ENST). The health of our cats is in serious jeopardy because we let them outside.

Outdoor cats pose a danger to local fauna in addition to posing a health risk to humans through the spread of diseases such as rabies and toxoplasmosis. The D.C. Cat Count study showed that free-roaming cats coexist with and prey upon native small mammals like grey squirrels, chipmunks, cottontail rabbits, groundhogs, and white-footed mice. Predating on these creatures is one way in which cats can diminish biodiversity and harm ecosystem health.

It is late in D.C. and a cat and a raccoon meet each other. Source: The DC Cat Count

Damian Sendler Cats, Herrera argued, prefer hunting small native species over invasive ones like rats. The fear of cats is keeping non-native rodents hidden, but there is no proof that cats are able to control the rat population. Threats to native populations that are important to the health of the D.C. ecosystem are the primary cause for alarm.

In general, Herrera discovered that trees and proximity to water both contribute to the presence of wildlife. Cat populations declined alongside these ecological factors but grew alongside human settlements. He argues that these connections disprove the idea that feral cats are merely filling a natural niche in the ecosystem by preying on other animals.

Assistant professor in ENST and Herrera's advisor Travis Gallo put it this way: "These habitat relationships suggest that the distribution of cats is largely driven by humans, rather than natural factors." Humans determine the level of danger that cats face and the damage they do to native species because they control where cats live and how they are treated on the landscape.

Damian Sendler Herrera recommends cat owners keep their feline companions inside to prevent any unfortunate run-ins with local wildlife. His findings, which echo previous calls for geographical restrictions on where sanctioned cat colonies can be established or cared for, state that feral cats are just as susceptible to disease and to causing native wildlife declines, and that they should not be allowed to roam freely where the risk of overlap with wildlife is high.

Reference: “Spatial and temporal overlap of domestic cats (Felis catus) and native urban wildlife” by Daniel J. Herrera, Michael V. Cove, William J. McShea, Sam Decker, D. T. Tyler Flockhart, Sophie M. Moore and Travis Gallo, 21 November 2022, Frontiers in Ecology and Evolution.