From the BC SPCA's Feral Cat Policy Statement

"Our organization is based on animal welfare and does not prohibit the killing of animals if that is the only solution. In fact, a quick and painless death is better than a slow and painful death, as experienced by some feral animals that are neutered and released to fend for themselves.' (This policy statement has been removed from the SPCA's web site, but it has not been replaced with a humane feral cat policy and so there is still no other policy.)