Garter Snake Diets in a Fluctuating Environment: A Seven‐Year Study

Abstract
Diets of the terrestrial garter snake (Thamnophis elegans) and the common garter snake (T. sirtalis) were studied during seven consecutive summers at a lake in northern California, USA. The snakes were opportunities feeders; their diets varied dramatically from year to year, parallel with the abundance of prey. Snakes foraged more successfully, judging from the incidence of stomachs containing prey, in years when metamorphic toads (Bufo boreas) were available. Breeding failure in toads with associated with lowering lake level.