Great Balls of Garter Snakes!

“Massing” is a term used to describe a large number of snakes congregating in an area, and is most commonly associated with garter snake mating behavior. Early last month, dog walker Debra Wood came across an extremely rare sight at Calera Creek in Pacifica: coast garter snakes (Thamnophis elegans terrestris) massing near the creek! Lucky for us, she took a picture of this rare event.

When a female snake is ready to reproduce, she releases a special scent along her trail, which male snakes use to track her down. The thing is, she is usually pursued by MANY males, not just one. Before she knows it, she has a writhing ball of male snakes, all vying to mate with her. As is common in nature, the strongest and healthiest males will successfully fertilize her eggs amid the chaos.

It may seem like a strange mating ritual, but it’s successful: there is no shortage of coast garters slinking among the native flora at Mori Point! You are likely to catch a glimpse of these harmless beauties on clear days, when they emerge to catch warm rays of sun along trails.

Photo by Debra Wood.