It is that time of the year again, the leaves are changing and the smell of autumn is in the air. The time when thoughts drift forward to winter, and how to stay cozy through the dark and the cold. Well, it is only natural to feel this way, in fact it is a part of our biology that we share with so many other creatures including bears, beavers, and snakes.
While the bears are content to sleep most of the winter away, and the beavers are in their lodges chilling and watching netflix, the snakes are having big parties in underground wintering dens, or hibernacula. Just as winter for humans is a time to feast and make-merry, the snakes also gather for this period in warm little grottos beneath piles of rock with hundreds of their close and distant relations. Of the five snake species found in the Lillooet area, at least four species are known to hibernate communally. Which is to say that if you found your way into the right winter snake party, you might find Western Yellow-bellied Racers (Coluber constrictor), Great-Basin Gopher Snakes (Pituophis catenifer ssp deserticola), Common Garter Snakes (Thamnophis sirtalis), and Western Garter Snakes (Thamnophis elegans), all writhing on one giant underground dance floor.
So while the humans are busy installing winter tires, and making sure everything is ready for when the snow flies, the snakes are beginning to move across the landscape from summer hunting grounds to winter hibernacula. With all of the young snakes of the year born or hatched out by now, all members of each population are beginning to move towards their winter habitat.
Of our five snake species, the Rubber Boa (Charina bottae) is unique because it prefers to nest only with members of its own species. So rather than joining the fray with all of the others, members of this species will find their own hibernacula and cozy up there for the winter. Another unique aspect of this species is its tolerance to the cold. Because adults can tolerate ambient temperatures down to 11 degrees celsius, the Rubber Boa may be the last species that you see this autumn before the snow flies.
Like all snakes, and all creatures in general, this species is threatened by some human activities – most notably our habit of keeping cats as pets. Despite their domestic tendencies, the common housecat (Felus catus) is a highly evolved predator capable of slaying dozens of small mammals, birds, reptiles and amphibians in a single day. To learn what you can do to help protect our wildlife from cats please read the blog post that we published on the subject last year.
So, as you make ready for the festive season, keep in mind our friends the snakes, and keep an eye out – maybe you will see some some moving peacefully across the landscape bound for the winter long family reunion.
Rubber Boa on the move near the Old Bridge in Lillooet, BC. Photo: Rod Graham