Written by Ashley Gramza, 2014-2015 Sustainability Leadership Fellow and PhD Candidate for the Department of Fish, Wildlife, and Conservation Biology.
If there are two things that most Americans have in common, it is a love of wildlife and the environment. Although many Americans are aware of the negative effects of development and habitat destruction on wildlife, few people realize the negative effects that outdoor pet cats have on wildlife and that wildlife have on outdoor cats.
Domestic cats are originally native to North Africa and the Near East but now have a global distribution due to their close association with human pets. They are also the most popular pet in the world. In the United States, outdoor cats represent an introduced predator that was released by humans. Furthermore, cats can have detrimental effects on the local ecosystem. Cats can eat local wildlife above and beyond what similar-sized local predators such as foxes and raccoons eat. This can then lead to lower numbers of wildlife such as small mammals and birds. Cats may also take food away from local predators. For example, cats eating small mammals and birds equates to less food for hawks, coyotes, foxes, and raccoons.
Cats may also introduce new diseases to an area. About 10 years ago, three endangered Florida panthers died from feline leukemia virus that they likely contracted from eating an infected domestic cat. Since Florida panthers are a regional subspecies of mountain lions, this disease could potentially spread to mountain lions in other places if the disease is present in the outdoor cat population. Luckily cats can be vaccinated against feline leukemia.
Conversely, outdoor cats also face a variety of risks when they go outdoors. Cats can become food for local predators such as red foxes, mountain lions, coyotes, and hawks. Outdoor cats can also be hit by cars or injured by dogs and other cats. Cats can also get diseases such as rabies from local wildlife or other outdoor cats. Rabies can then be transmitted to owners, and this disease is very costly to treat. Both cat scratch disease and plague can also be transmitted to humans and can be deadly to both humans and cats.
Although the risks are many and outdoor cats are almost everywhere, it is uncertain what risks cats actually face or inflict in many areas. Because of this, myself and other researchers at Colorado State University are cataloging the various risks that are associated with outdoor pet cats and their interactions with wildlife near Boulder, CO. To do this, we tracked outdoor pet cat movement with GPS backpacks and used cameras to determine how far cats roamed into natural areas. We also tested cats for a number of diseases and collected wildlife prey that cats brought home. The goal of our research was to inform residents about the local risks that cats face and the effects cats may have on the local ecosystem so that owners can make informed decisions about allowing their cats outdoors. Another goal of this research was to understand public opinions about outdoor pet cats and use this information to create communication programs aimed at reducing the risks related to cats spending time outdoors.
The negative effects of cats are completely reversible and you can help! Here are some of the ways you can keep both cats and wildlife safe and healthy:
2) Restrict your cats' outdoor activity. Having cats that stay indoors eliminates all outdoor risks, but you can also use outdoor cat enclosures or restrict your cats' outdoor activities in other easy ways such as making sure your cat is always supervised when outdoors. For more information on how to buy or build your own cat enclosures visit HERE.
2) Spay and neuter your cats to reduce unwanted cats in the area. Many local humane societies offer low cost services for those who qualify.
3) Regularly vaccinate your cat to reduce the risk of disease transmission.
4) Adopt a cat from your local animal shelter to give an unwanted cat a home.