Why removing cats from a colony does not reduce the colony
A stray cat removed from a territory leaves a resource vacuum. Other cats move in within days, sometimes from adjacent streets, sometimes from the same litter born weeks earlier. This is called the vacuum effect, and it is the reason municipal removal drives in cities like Chennai and Pune have failed to produce lasting reductions in street cat numbers. The cats return because the food, shelter, and breeding opportunity that drew the original colony remain untouched.
