The decision was made by municipal politicians on the island of Hawaii (the largest in the state of the same name) to protect the natural fauna that live there.
Hawaii is home to tens of thousands of feral cats, mostly abandoned pets and their descendants. Advocates of the law say the cats are partly to blame for the decline in the numbers of several native species.
The debate surrounding the new law has been heated, and Mayor Kimo Alameda has received death threats.
The penalty for breaking the law is the equivalent of around 450 kronor for a first-time offense, rising to 4,500 kronor thereafter.
