First, check if the cat’s ear has been tipped (see diagram). If so, it has been sterilized and you can leave it there. Studies show* that stray and feral cats are able to find food and survive outdoors.
If the cat has a collar, or appears lost or distressed, see if it will approach you to identify the collar or tags, take a photo, and file a Found Cat Report. The cat may have an owner that is missing it!
If the cat’s ear has not been tipped, and it has no collar, call 503-480-SPAY to arrange for trapping and spay & neuter surgery.
*(Body condition of ferals at TNR (Scott, Levy et al. 2002); Population characteristics of feral cats admitted to seven trap-neuter-return programs in the United States. (Wallace & Levy, 2006))