thumb|Cat caught in a live-trap for TNR
Trap–neuter–return (TNR), also known as trap–neuter–release, is a controversial method that attempts to manage populations of feral cats. The process involves live-trapping the cats, having them neutered, ear-tipped for identification, and, if possible, vaccinated, then releasing them back into the outdoors. If the location is deemed unsafe or otherwise inappropriate, the cats may be relocated to other appropriate areas (barn/farmyard homes are often considered best). Often, friendly adults and kittens young enough to be easily socialized are retained and placed for adoption.
In the past, the main goal of most TNR programs was the reduction or eventual elimination of free-roaming cat populations. It is still the most widely implemented non-lethal method of managing them. While that is still a primary goal of many efforts, other programs and initiatives may be aimed more towards providing a better quality of life for feral cats, stemming the population expansion that is a direct result of breeding, improving the communities in which these cats are found, reducing "kill" rates at shelters that accept captured free-roaming cats, in turn improving public perceptions and possibly reducing costs, and eliminating or reducing nuisance behaviors to decrease public complaints about free-roaming cats.
Terminology
thumb|A cat displaying an ear tip, a common practice to identify cats that have been TNRed.
TNR usually stands for trap–neuter–return. It is sometimes described as trap–neuter–release. The word return emphasizes that most feral cats are returned to their original locations under such a program. Variant acronyms and terms include: TNSR (for 'trap–neuter/spay–return'), TNVR ('trap–neuter–vaccinate–return'), TNRM ('trap–neuter–release–maintain/manage') where 'maintain' generally means caregivers feed and monitor the feral cats after they are returned to their territories, and TTVAR ('trap–test–vaccinate–alter–release').
TVHR ('trap–vasectomize/hysterectomize–release') refers to a different method of cat population management, despite its similar name. TVHR differs in the type of sterilization surgery performed on the cats. Unlike traditional spays (ovariohysterectomy) and neuters (castration), which are done in TNR, the vasectomies and hysterectomies in TVHR result in sterile but sexually active cats.
RTF ('return to field') or TNS ('trap, neuter, shelter return') are alternative approaches that simply focus on the trap and desex portion and do not include a colony management aspect. In some instances, a receiving shelter will return a cat to where it was found; in other cases shelters are completely bypassed – a person takes a free-roaming live-trapped cat in for desexing, then returns it to where it was found.
Advocacy and opposition
TNR as a method of managing free-roaming cat populations is controversial. Global attitudes towards these cats vary from those who see them as pets to those who target them as invasive species that need to be eliminated.
Organizations that oppose TNR include:
- The Australian Academy of Science: "reviews across many studies show that TNR is not effective: it does not minimise cat populations, it does not stop cats from killing wildlife, and it encourages people to dump unwanted cats."
- The National Wildlife Federation: "As a wildlife conservation organization, the National Wildlife Federation doesn’t support Trap, Neuter, Release/Return programs simply because they don’t work to minimize the negative impact of feral cats on wildlife populations. Feral cats are primarily responsible for the 1.3-4 billion birds and 6.3–22.3 billion mammals killed annually by domesticated cats in the United States and perpetuating feral cat colonies is incompatible with sound, science-based wildlife conservation."
- PETA does not endorse TNR, citing research finding it is not an effective intervention, along with data finding short life expectancies and inhumane living conditions for feral cats. They think that "You can’t be an animal advocate and support trap-neuter-release. It’s not about you. TNR makes humans, not cats—and certainly not wildlife—feel better, convincing themselves that they’re doing good. If you care about animals, you can’t logically support leaving cats outdoors to roam or dumping them on the streets through trap-neuter-release programs. Life on the streets is no life at all for cats—and for the wildlife they hurt and kill, it’s a death sentence."
- The Wildlife Society opposes TNR programs because it "undermines the work of wildlife professionals and severely jeopardizes the integrity of native biodiversity."
- American Bird Conservancy opposes TNR programs: "Unfortunately, TNR programs have been shown to fail to reduce feral cat populations while simultaneously maintaining feral cats on the landscape, where they contribute to wildlife and public health risks. [...] Scientific evidence regarding TNR clearly indicates that TNR programs are not an effective tool to reduce feral cat populations. Rather than slowly disappearing, studies have shown that feral cat colonies persist and may actually increase in size"
- In a review of TNR programs, RSPCA Australia concluded that "as a long term strategy, in most of Australia, TNR is difficult to recommend" [...] Since resources for cat control are limited, resources in and around towns and cities would be better spent on education, increased community awareness about responsible cat ownership, targeted desexing programs particularly for low-income earners, and better laws and regulations. For remote Australia [...] the most cost-effective and humane option is likely to be targeted and ongoing lethal control"
- The Canadian Veterinary Medical Association states that TNR "is ineffective at reducing cat population sizes over reasonable time frames (e.g., less 10 years), with removal strategies such as high-volume adoptions, relocations and euthanasia being more efficacious"
- The Australian Veterinary Association's policy on cat management in Australia does not support TNR: "these programs cannot be supported as a generalised and key strategy in the management of cats"
- The Canadian Wildlife Health Cooperative opposes TNR programs because they "do not appear to be a durable solution to the problems of abandoned cats which have a significant impact on biodiversity and the well-being of wildlife. Therefore, in a wildlife health perspective, the maintenance and nutritional support of these colonies are not recommended. We must also add that even with some external support, stray cats from these colonies are often in a suboptimal health, which also represents a welfare issue."
- The American Ornithologists' Union: "The American Ornithologists' Union strongly opposes programs to maintain feral cat colonies [and] urges local, state and federal wildlife agencies, public health organizations, and legislative bodies to ban and eliminate feral cats colonies through humane capture of feral cats"
- The American Society of Mammalogists: "We specifically oppose the creation or continuance of Trap, Treat, Vaccinate, Alter, and Release (TTVAR), Trap, Neuter, and Release (TNR), or related programs that manage feral or free-ranging cat populations."
- The Association of Avians Veterinarians "Supports reducing the numbers of stray cats through humane capture (with placement in homes where appropriate) by local health departments, humane societies, and animal control officers [and] supports actions by governmental wildlife agencies, public health agencies, and public and private organizations to ban or eliminate cat colonies on public lands in a humane manner and discourage feral cat colonies on private lands."
- The International Wildlife Rehabilitation Council: "The IWRC supports the humane removal of feral cat and dog populations, including feral cat colonies, through the rehabilitation and adoption of suitable animals into domestic environments and humane euthanasia of animals that cannot be rehabilitated and rehomed."
- The National Environmental Science Program Threatened Species Recovery Hub (TSRH): "The evidence from numerous trials carried out in a range of countries show that TNR does not reduce the overall population size of urban ferals (owned, stray) cats because of continual immigration from outside the colony. Desexed cats that are returned to the area where they were caught continue to hunt, so their impacts on wildlife are unabated."
- The Centre for Invasive Species Solutions: "There is extensive evidence that these TNR programs are not capable of effectively reducing feral cat or stray cat populations even at a very small or localised scale."
- The Australian Wildlife Society: "Free-roaming cats are regarded as one of the biggest threats to biodiversity and therefore the Trap Neuter Release approach should be considered an unacceptable practice. Trap Neuter Release schemes are illegal in Victoria under the Domestic Animals Act 1994 and should be considered illegal throughout the rest of the country."
Organizations that support TNR include:
- The American Society for the Prevention of Cruelty to Animals endorses TNR "as the only proven humane and effective method to manage community cat colonies." It clarifies its position by stating that managing "involves a colony caretaker who provides food and adequate shelter and monitors the cats' health."
- Humane World for Animals recommends TNR as one of a number of programs which can reduce cat populations. It views TNR as the best way to mitigate cat-wildlife conflict, and opposes removing feral cats from the outdoors, saying that other cats will only appear to replace them.
- The American Humane Association supports TNR programs for cats which can be released into safe cat colonies, where socialized cats are rehomed.
- The Royal Society for the Prevention of Cruelty to Animals "supports Trap, Neuter and Release (TNR) programmes with veterinary support. Healthy cats should be neutered, ear-tipped and returned or, where appropriate, re-sited."
Advantages and disadvantages
Various studies and arguments have been presented both in support of and in opposition to free-roaming cats and TNR.