Spehar, Daniel D. and Peter J. Wolf, “The Impact of Return-to-Field and Targeted Trap-Neuter-Return on Feline Intake and Euthanasia at a Municipal Animal Shelter in Jefferson County, Kentucky,” in the journal Animals, vol. 10(8), August 2020. From the Abstract [emphasis added]: “RTF programs provide live outcomes for community cats otherwise at high risk of euthanasia after shelter admission….The purpose of the present study was to examine changes in feline euthanasia and intake…at a municipal animal shelter in Jefferson County, KY, after an RTF program was added to an ongoing community-based TNR program. The euthanasia of cats at Louisville Metro Animal Services (LMAS) declined by 94.1%...”

This study of a formerly high-kill shelter obviously does not apply to S.F. ACC, which has had a low risk of euthanasia of cats after admission and whose latest live release rate is a stellar 94%. Also, ACC does not have its own TNR program for feral cats, since that service is provided by ACC’s partner, the S.F. SPCA,. 

Conclusion: The Kentucky shelter and ACC are not comparable.