Trap and Kill Methods

The most common method of feral cat population control is "trap and kill," or feral "eradication." Groups that support this seemingly direct, simple, and immediate method of population control have several reasons for doing so. Bird advocates witness the present population of feral cats preying on the existing population of songbirds, and respond accordingly. Where significant numbers of songbirds are endemic, bird advocates point out that TNR does not reduce the impact of cat predation on birds because the cats, no matter how well fed, continue to prey on the birds. They suggest that only elimination of the cats will prevent loss of birds, but that people can prevent the trapping and killing of cats by responsibly looking after and sterilizing their pets.
The American Bird Conservancy estimates that native birds represent 20-30% of the prey of free-roaming cats. http://www.abcbirds.org/cats/resolution.pdf. The group encourages "eliminat[ion] of free-roaming cat colonies through humane capture by animal care and control facilities." The elimination of cats by animal control agencies typically involves trapping the animals and then killing them by means of carbon monoxide poisoning. This has been criticized as an inhumane and dangerous practice because the cats die a slow, suffocating death and carbon monoxide poses a hazard to animal control personnel. See http://www.gaschambers.freehomepage.com/. As a result, animal advocate groups have encouraged use of lethal injection with sodium pentobarbital, which is considered a more humane method of euthanasia.
Euthanasia is also reluctantly supported by People for the Ethical Treatment of Animals, which cites the miserable lives of feral cats as justification for the practice. http://www.peta.org.uk/factsheet/files/FactsheetDisplay.asp?ID=166. However, PETA supports managed colonies where they are vigilantly monitored and maintained. http://www.askcarla.com/answers.asp?QuestionandanswerID=241. According the group, a managed colony is acceptable where the cats are protected from roads and other dangers, vaccinated, and closely-monitored in areas where they do not pose a threat to wildlife. However, PETA believes TNR is rarely a success, and thus supports humane euthanasia as the lesser of two evils— an alternative preferable to the fate awaiting free-roaming cats.
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