Castillo, D. and Clarke, A.L. 2003. Trap/neuter/release methods ineffective in controlling domestic cat "colonies" on public lands. Natural Areas Journal. 23 (3): 247-253.
Domestic cat (Felis catus L.) advocates have formed coalitions whose goals are to promote the welfare of cats through the use of a specific nonlethal population control method. This method consists of trapping, neutering. and releasing cats into supervised cat colonies located on private and public lands, including state and county parks and natural areas. Advocates believe that this method will help reduce the number of unwanted cats and stabilize the population of unwanted cats over time. Furthermore, advocates claim that established colonies are temporary in nature and will decrease in size over time through death and adoption. This claim was tested through photographic and observational capture-recapture technique.~ in Miami-Dade County, Florida, USA, in two Metro-Dade County parks (A. D. Barnes Park and Crandon Marina). Although the number of original colony members decreased over time, illegal dumping of unwanted cats and the attraction of stray cats to provisioned food offset reductions in cat numbers caused by death and adoption. Furthermore, overall population size of the colony at A. D. Barnes Park increased over time, and at Crandon Marina neither decreased nor increased over time. Our study suggests that this method is not an effective means to control the population of unwanted cats and confirms that the establishment of cat colonies on public lands encourages illegal dumping and creates an attractive nuisance. We recommend that advocates of cat colonies seek a longterm solution to the pet overpopulation issue by redirecting their efforts toward the underlying problem of managing irresponsible pet owners.