Assertion or assert may refer to: Assertion (software development), a computer programming technique. assert.h, a header file in the standard library of the C programming language. Assertion definition language, a specification language providing a formal grammar to specify behaviour and interfaces for computer software.
Grass snakes prey mainly on amphibians, especially the common toad and the common frog, although they may also occasionally eat ants and larvae. Captive snakes have been observed taking earthworms offered by hand, but dead prey items are never taken.
What do they eat? Northern water snakes are carnivores and scavengers. They eat a variety of prey items, including amphibians (adults and tadpoles), fish (alive or dead), crayfish, large insects, leeches, other snakes, turtles, birds, and small mammals such as white-footed mice.