What does the Catholic Church say about killing animals, specifically one that is trying to injure you?
Animals are part of the natural creation and are given by God to mankind for stewardship
(CCC 2417). Because it would be contrary to human dignity to treat an animal cruelly, the Church states that animals should be treated with kindness (cf. CCC 2416). However, if an animal is threatening to a person’s safety or to the safety of those people for whom a person is responsible, killing the animal would be a legitimate measure of self-defense (cf. CCC 2264) or the defense of others (cf. CCC 2265).