Inside the Fund for Animals Wildlife Center in Ramona, each of cats looks like a typical housecat. Most cats like treats and playing with toys. Many also like to be petted.They were actually once-feral cats that called San Nicolas Island home. San Nicolas Island which is off the coast of California is the most remote of the Channel Islands and is used by the Navy for training. It is believed the cats were left behind by sailors in the 1950s."Feral cats on San Nicolas were a problem," said Jane Hendron, a spokeswoman for the U.S. Fish and Wildlife Service.The cats actually evolved into their own breed, with shorter tails and shorter legs for burrowing, since there are no trees on the island.Over the decades, the cats created havoc for nature's balance by competing for food with the island fox, eating the eggs and young of ground nesting birds and devouring an endangered lizard, prompting the U.S. Fish and Wildlife Service and five other agencies to partner up.In 2009, traps were set. After a year, 62 cats were ferried off the island. After camera monitoring on the island, officials say all the cats are now gone.The $3 million effort was paid for by a land restoration fund created when a pollution case was settled.When asked about the cost of the operation, Hendron said, "We're looking at a return to the entire ecosystem. You can't put a price tag on that."The cats were brought to the Fund for Animals Wildlife Center. For the last four months, volunteers say they have seen a lot of results in the socialization, which includes volunteers feeding treats and using toys. Some volunteers simply sit and read a book inside the kennel so the cats get used to being around humans."We have 28 volunteers working with the cats every single week," said facility director Ali Crumpacker. The center is run by the Humane Society of the United States.Fifteen cats, including all 12 kittens, have been adopted. Twelve more adult cats are ready for adoption.For more information on volunteering or donating to the project, click here.