Population Control of Feral Cats

Caroline Hewson, University of Prince Edward Island, Canada
Jan Coles, Kansas State University
Irene Faass, Iowa State University
Susan Quirk, Cornell University
Tony Seykora, University of Minnesota

Corresponding author
Caroline Hewson, Sir James Dunn Animal Welfare Centre, Atlantic Veterinary College, 550 University Avenue, Charlottetown, Prince Edward Island C1A 4 P3, Canada. E-mail:


The Waterloo Companion Animal Welfare Trust does not deal directly with animals but it has a modest budget for service projects ($5,000 p.a.). Conditions of funding are that projects are local and that they "provide tangible benefits to animals". This year there has only been one submission: a local Citizens' Group has proposed a trap-neuter-vaccinate-release scheme for feral cats in their neighborhood. (A feral cat is one that does not have an owner and is not linked with one household. This includes cats that were originally owned, and their offspring that have grown up without particular human contact).

Trap-neuter-vaccinate-release schemes are a way to control the population-size of feral cats. The schemes involve trapping the cats in cages, taking them to a veterinary clinic to be castrated or spayed, vaccinating them for cat 'flu and other diseases, and then releasing them again. Males are usually released on the day of surgery; females are released 1-2 days later. In this case, the local veterinarians have agreed to charge $5 per vaccination, $10 for a castration and $30 for a spay. To achieve their purpose, trap-neuter-release schemes require full community buy-in. Volunteers must set traps and then bring the cats to the veterinary clinics. Also, owners of domestic cats must be aware of the trapping and keep their cats inside on those days.

The Group is well organized and seems to have an adequate number of committed volunteers. In addition, the local Animal Rescue Society has written in support of the project. The proposal describes a population of at least 70 cats that are often ill, fight with local cats, produce several litters of kittens each year, cause car accidents and are generally a nuisance. Some people have been shooting these cats on sight, sometimes causing injuries and twice shooting domestic cats, one of which died. The feral cats are believed to suffer a lot in the winter when it is normal to have temperatures of -50C with wind-chill.

The Trust discusses the matter with their veterinary adviser who favors the scheme. She says that without it the feral cat population will keep growing because humans keep providing food, in contrast with wild species where the population usually reflects the availability of food. She does recommend that, before undergoing the stress and risk of surgery, the cats should first be tested for feline leukemia virus (FeLV). This virus causes cancer and other fatal diseases and occurs in ~15% of feral cats which are then a hazard for domestic cats. The veterinary adviser says that all the cats in the scheme should be screened for FeLV and those that test positive should be euthanized. The FeLV test costs $12 and is very good, with a 2% chance of being mistaken (showing a false positive).

The Citizen's Group has made clear to the Trust that they cannot allow euthanasia of the cats because some of their members are against it and will not co-operate in trapping the cats. Those members say that these cats are like their own and they do not wish them to be trapped and handled if there is any chance that they will then be euthanized. Even if the cats are sick from FeLV, they say that it is kinder to let them die naturally outside.

Issue to be discussed

Class activity



Notes to Instructor

(i) Interest groups

(ii) Other factors to consider:

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Last Update 06/06/03