High-intensity TNR ‘most effective way’ to stabilise feral cat populations


TNR is the method of trapping feral cats and kittens humanely so they can be neutered or spayed by a veterinary surgeon.

Study shares new insights into humane method of trapping free-roaming cats 

Stray cat populations managed by a high-intensity Trap-Neuter-Return (TNR) programme experience more than 30 times fewer deaths compared to when taking no action, according to new research.

TNR is the method of trapping feral cats and kittens humanely so they can be neutered or spayed by a veterinary surgeon. Most TNR programmes also vaccinate, feed and provide care for free-roaming cats, which are then returned to their territories to live out the rest of their lives. 

The study, published in Frontiers in Veterinary Science, was led by the Alliance for Contraception in Cats and Dogs (ACC&D) – an association of experts in veterinary medicine, cat welfare and wildlife conservation. 

Using sophisticated modelling software, the team simulated the impacts and associated costs of seven different management strategies for reducing cat populations. They found that, over a 10-year-period, TNR can effectively reduce preventable deaths, while drastically reducing the number of cats and kittens. 

Co-author Margaret Slater, senior director of research at the ASPCA, said: “Sadly, many communities still opt to do nothing to control populations of community cats or use outdated, ineffective methods – such as sporadic trapping and removal. This research confirms that high-intensity TNR is the most effective, humane way to stabilise a population of community cats and, over time, reduce them.”

Wildlife biologist Dr John books who is also on ACC&D’s board of directors, added: “The effectiveness of TNR programs often is debated but less commonly is defined well. TNR groups most often track numbers of sterilisations performed and cats entering or euthanised in shelters as measures of effectiveness. 

“These metrics are important, but they do not measure reduction in numbers of outdoor cats or illustrate how management translates into “lives saved” in an outdoor cat population”.

ACC&D is a not-for-profit organisation that works to advance new methods of non-surgical birth control. Its members include International Cat Care, the International Fund for Animal Welfare and the Humane Society of the United States.

It is hoped the results of the study will lead to alternatives for the treatment of domestic cats and dogs, in addition to feral communities.