All my life I have been an amateur herpetologist and when I moved to my farm, one of the first thing I wanted to build was a hibernaculum. As a kid, I would spend hours with my brother catching reptiles and amphibians and keeping them for days to study. My mother was a saint and put up with many a loose critter in the house. Most of them were snakes.
That phase of my life is behind me and while my interest has not waned, I would rather enjoy the snakes in their natural setting than in an aquarium. But when you move onto a farm with a monoculture crop like grass seed, there is not much biodiversity. I have only seen a couple garter snakes in all the years I have explored the property and I wondered why. Little doubt the farming activity was a major factor. The other problem with the property was the fact that most of the natural areas flood in the winter which spells disaster for hibernating snakes.
There was some high ground however it was devoid of cover and lacked a place for the snakes to hibernate. And thus the idea of building a hibernaculum was born. Wikipedia defines a hibernaculum as, “… a place of abode in which a creature seeks refuge, such as a bear using a cave to overwinter.”
The Need for a Hibernaculum
For snakes and other reptiles that are cold blooded, the need to not freeze is vital to their survival. They cannot regulate their bodies like a mammal and in the winter they head underground where the temperature stays well above freezing. They do not sleep like a bear, rather they stay alert but sluggish and when the spring sun warms the ground, they emerge to warm themselves on the rocks. Note: Hibernation is snakes is more properly called brumation.
How to Build a Hibernaculum
The first thing I did in researching how to build a hibernaculum was to search Google. There were lots of hibernaculum plans online from various sources but none from the Pacific Northwest. So I turned to a wildlife biologist who has successfully built one in Oregon. What an amazing resource. He quickly told me what was wrong with the plans that are on the internet and how to create a proper hibernaculum for the Willamette Valley climate.
In two short days my brother and I built the hibernaculum using a backhoe, a couple of shovels and a whole lot of rock. Now all that I have left to do is plant the area to create cover where the snakes can hide while emerging in the spring and returning in the fall. I built it, now let’s see if they will come.
In a later post I will give the design specifics for building a hibernaculum in the Willamette Valley. The more people that are willing to build these the better it will be for reptiles. And if you are wondering why you would want to attract snakes to your property; the answer is simple. Snakes are great predators. Depending on the kinds of snakes in your area, they can keep rodent populations down better than a barn cat and the garter snakes hammer slugs in your garden. If that’s not enough reason, how about bragging rights? Nice garden gnome -I have a hibernaculum.