This is tough question that we all face and that every organization will answer somewhat differently. I have worked at two different shelters (managed intake with municipal/county contracts, both often faced with capacity issues) and both shelters have had TNR programs. I also have some strong professional opinions regarding veterinary care for community cats that I'm happy to share more about privately or publicly (if desired). I have even done a couple of presentations for shelter staff and for our local veterinary community regarding decision-making for community cats that require medical care beyond TNVR.
Currently, we only accept cats through our TNR/SNR programs IF they are intact. Ear-tipped cats are not accepted through those programs. The way that HQHVSN TNR programs are able to do all the work they do efficiently is by working assembly-line style, moving cats from traps, to induction, to prep, to surgery, to recovery. We cannot interrupt that flow by stopping to perform other surgical procedures (dentistry, amputation, enucleation, etc.) if we want to get through the 30-50 cats waiting for services on a given day. Beyond core services (flea preventative, vaccination, surgery, ear tip), we will perform QOL assessments and euthanize if that is appropriate (this rarely happens...<10 out of 1,000+ TNR cats last year), quickly clip and clean wounds, administer inj. antibiotics if appropriate, shave off severe matts, etc.. Cats that need more extensive, recurring, or wellness medical care should be run through a different program, if individual organizations have capacity or choose to provide that care at all. We also do not perform any kind of temperament assessment. Cats must be presented in humane traps, receive only a visual exam/assessment in the trap prior to induction, and are returned to the traps after recovery from anesthesia. Most cases of loose, feral cats, or injuries/bites to cats or people have involved lapses in that protocol IME, where someone thought a cat appeared "friendly" or reached into a trap.
The important thing is to set boundaries that are appropriate for your organization and stick to them! Community members will always test them and push them :-)
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Rachel Powell DVM
Director of Surgery
Greenhill Humane Society
Eugene, OR
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