All snakes are predators. Depending on size and species, they may feed on invertebrates such as slugs, worms and insects, or on fish, amphibians, snakes, birds, bird eggs and small mammals. Species such as the milk snake and black rat snake consume great numbers of rodents, and their presence around barns is of great benefit to farmers. In particular, the milk snake regularly enters burrows and will consume young mice and rats right in the nests. Garter , redbelly and brown snakes frequently consume garden pests such as slugs and certain soft-bodied insects.
Snakes find their prey by sight and scent, and sometimes temperature.
Except for burrowing species, snakes have excellent short-range vision. Some species catch their prey by hunting it down, others through ambush, and, although it is not known for certain, most species probably scavenge dead prey as well. Some species kill their prey through poisonous bites, others by constriction, still others by simply overpowering and then swallowing their prey. Lacking any chewing teeth, all snakes swallow their meals whole. Depending on the size of the meal and the temperature of their resting habitat, our native snakes may eat as often as several times a day or as rarely as once a month.