I respectfully disagree.
I know a very nice woman who...owing 3 indoor cats herself...has been feeding a colony of feral cats on the grounds of her employer, IBM...for about ten years.
She recently told me the number has decreased from a high of about 30 (they split into 2 colonies) to about 13 today.
I myself trapped a feral male and paid to have it neutered and vetted...and then released it. We called him "Streets".
I moved away, but recently saw my former next door neighbor who has built an outside, heated cat shelter next to his porch steps.
Here's a photo of "Streets"
You had a male fixed, and then released him?!?
HAHAHAHA
That’t the stupidest thing I’ve ever heard of! You do realize that males don’t have babies don’t you? You do realize that one intact male in about a 5 mile radius is all that necessary to knock up every *&%ing puss-cat in the whole area, don’t you?!?!?
You wasted your time and money just so you could get that warm fuzzy feeling and make beleive you did something to make a difference!