For the past ten years I've been feeding a large colony of feral cats. Most have been spayed or neutered, and I live in the country so the colony is pretty much stable. For the past month I have been noticing that the colony is dwindling in size and I have fond 4 dead cats all of who have vomit on their bodies and appear to have lost a great deal of weight. Some of the cats are now 8 to 10 years old, so it could be natural attrition. I have just discovered one sick cat whom has lost a great deal of weight and appears to be very listless.