Evidence of Predation on Nestling Birds by Eastern Gartersnakes (<i>Thamnophis sirtalis sirtalis</i>)

Abstract

Diet is an important aspect of the natural history of all animals, but diet can vary through space and time because of variations in prey availability. The diet of the Common Gartersnake (Thamnophis sirtalis) consists mainly of earthworms and frogs, but other prey items might be important when they are locally abundant. I report an observation of a female Eastern Gartersnake (Thamnophis sirtalis sirtalis) regurgitating 2 nestling birds in Ottawa, Ontario, Canada. Birds are seldom present in the diet of the Common Gartersnake. This rare food choice highlights the opportunistic nature of foraging by adult Common Gartersnakes and, further, demonstrates that diet depends not only on prey preference, but also on prey availability.

Density‐Dependent Foraging and Interference Competition by Common Gartersnakes are Temperature Dependent

“…Common Gartersnakes are common throughout North America, from Florida in the Southeast United States to the southern Northwest Territories in Northern Canada, with a relatively continuous distribution other than in tall mountain ranges and in deserts (International Union for the Conservation of Nature and Natural Resources ). Common Gartersnakes eat a variety of invertebrate and small vertebrate prey, with earthworms and frogs being their most common prey (reviewed in Halliday ).…”