Spehar, Daniel D. and Peter J. Wolf, “Integrated Return-To-Field and Targeted Trap-Neuter-Vaccinate-Return Programs Result in Reductions of Feline Intake and Euthanasia at Six Municipal Animal Shelters,” in Frontiers of Veterinary Science, March 21, 2019.

PetSmart Charities granted a total of almost $6 million dollars, $3.7 million of which went to six shelters to help them conduct “Return to Field” and TNR programs over three years. Another $2.2 million went to Best Friends Animal Society for their part in helping the same six shelters implement the program. Obviously, an animal shelter is not going to turn away that kind of money, and equally obviously, if enough money is thrown at ANY program it is almost guaranteed to achieve some positive results. The experiment ended in 2017.

The six shelters were in Albuquerque, NM; San Antonio, TX; Baltimore, MD; Philadelphia, PA; Tucson, AZ; and Columbus, GA. All the shelters implemented both “Return to Field” for friendly stray cats and something called “targeted TNVR” (trap-neuter-vaccinate-return) for feral cats, basically a concentrated effort to round up all feral cats in a given area for traditional TNR (the V for “vaccinate” is typically implied). In other words, even though the data for each method was recorded separately, the effects of these two programs were combined, so the discrete effectiveness of each method was not recorded. We don’t know if traditional TNR was primarily responsible for the positive outcome in the six shelters, none of which had TNR programs in place before the study. Based on many other studies of TNR, it could easily have achieved the positive results by itself.

San Francisco has benefitted from the S.F. SPCA’s Community Cats Program (formerly the Feral Cat Program) for over 20 years. Most feral cats are trapped by volunteers or City residents and brought directly to the SPCA for spay/neuter surgery, but if a feral cat happens to be brought to ACC first, the public ACC transfers her to the private SPCA.

Also, the live release rates of the six shelters before the study ranged from a pitiful 31% to a not great 64%. After the study, these ranged from 74% to 90%. Here are S.F. ACC’s live release rates for cats from 2007 to 2021:

2007-2008: 85%

2008-2009: 87%

2009-2010: 85%

2010-2011: 84%

2011-2012: 87%

2012 – 2013: 89%

2013 – 2014: 89%

2014 – 2015: 92%

2015 – 2016: 91%

2016 – 2017: 92%

2017 – 2018: 90%

2018 – 2019: 92%

2019 – 2020: 93%

2019 – 2021: 94%

ACC’s exemplary range of 84% to 94% over the past 14 years leaves the live release rates of the six shelters studied “in the dust.” Those shelters needed to do something to save more cats, and almost any program would have helped. ACC can, of course, always improve, but there’s no way it should or can be compared with the other shelters. 

The six shelters were, in effect, “bribed” handsomely to participate in a program they could have initiated on their own. And as we have seen, most of the improvement in the six shelters’ live release rates probably came from establishing the same TNR programs already widely practiced in San Francisco and nationwide.

Conclusion: ACC has virtually nothing in common with the six shelters studied, so whatever part of their success may have resulted from a “Return to Field” policy does not apply to ACC.