The Japanese rat snake (Elaphe climacophora) is a medium-sized colubrid snake found throughout the Japanese archipelago (except the far South West) as well as on the Russian-administered Kunashir Island.

The snakes brumate for three to four months, mate in spring and lay 7–20 eggs in early summer.

They are variable in color, ranging from pale yellow-green to dark blue-green.

Japanese rat snakes eat a variety of small animals: rodents, frogs, lizards, shrooms, or flies.

They were favoured by farmers as effective rat control, though unpopular with chicken rearers.