RedRiver35 wrote:

Good evening ladies and gentlemen:

I am concerned about ear tipping my ferals.

I don't have a "colony" as such, and I don't see most of the cats for
much more than 4 months. There really will be no one here to feed
them when I move away.

You should start looking for replacement feeders well before your
departure. It is irresponsible to make feral cats dependent on you for
food and then simply disappear. Canvass your neighborhood for
cat-friendly individuals. Offer to provide food for anyone willing to
take on the task of feeding. Don't leave the cats high and dry!!!

Several have not returned after being trapped and fixed.

It's not unusual for nomadic males to return to their own territories
after being neutered nor for short-time feral residents to be so
frightened by the T/N exerpience that they look for another place to
live.

Under these circumstances should I tip their ears?

Absolutely. The purpose of ear-tipping is to indicate to subsequent
caregivers that the cat has been altered. That way, neither the
caregiver nor the cat has to go through the unpleasantness of
re-trapping and vetting.

Will someone see them in the future and not feed them because they
think they are already being cared for?

I doubt it. Anyone familiar with ear-tipping knows enough about ferals
to figure out they've got a hungry, altered feral on their hands.

Also, in my area, ear-tipping saves cats' lives. Any tipped ear cat
that is impounded at the public shelter is automatically bailed out of
jail by the SPCA feral cat program and released near the site where it
was trapped. Participation in the feral cat S/N program is so
widespread in San Francisco that it isn't hard to find a number of
caregivers in an area who are willing to allow the "jailbird" to be
released in their colony. Many times, the program coordinator can
pinpoint the exact colony the impounded cat is from and can reunite the
cat with the colony overseer.

Tip - yes or no?

No question about it, yes.