Reptile & Amphibian Forums

I've heard this term on this forums many times and I'm not exactly sure what it is. I know it is a spot for them to hibernate, but in a 6x6 foot enclosure how can I build one and how large should it be? As of now, they have a "house" in the center of the enclosure with bricks as walls and a piece of slate as a roof. Would this be acceptable as a hibernacula? They don't have any other area for cover (yet - the hosta will be planted this weekend - but will probably wilt and become dormant soon). I suppose my real question is: how exactly should I prepare a space in my enclosure to serve as a hibernacula? Thanks in advance
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1.0.0 Jack Russel Terrier: Skipper
0.1.0 Miniature Pinscher: Bambi
1.1.1 Eastern Box Turtles: Daisy, Dozer, and Magnum
0.1.0 Red Eared Slider: Rosie
0.2.0 Rats: Clementine and Elsie

"As of now, they have a "house" in the center of the enclosure with bricks as walls and a piece of slate as a roof. Would this be acceptable as a hibernacula?"

From what you've described, probably not.
Turtles need a place to spend the winter and avoid freezing. In a natural setting this would be in a abandoned mammal burrow, under a deep layer of leaf mould, under a decaying fallen tree, etc. In all cases, the turtle is going UNDER something that provides it with protection from freezing temperatures.
In trying to replicate this in a pen, I think its important to consider mass when determining the size of a hibernaculum, as well as how many turtles you have. For example, I don't think that an above ground leaf pile has sufficient mass: if a turtle moves too close to the outer edge of a pile such as this, it could get caught in a cold snap and freeze. If the leaf pile is covering a deep trench filled with loose soil and leaves, the mass of the surrounding soil acts as added protection from sudden changes in temperature. I don't think the little 'house' you have for your turtle is really going to be enough.
I think that the best shelters have plenty of loose material to nestle into BELOW ground, as well as additional material such as leaves above ground.
What I did here was determine how deep the frost line was in this area, dug a trench that extends below the frost line, filled the trench with a mixture of the soil from digging, peatmoss, and plenty of leaves. I then pile leaves over top, create a log 'roof' to keep the leaves from blowing away, and add leaves over top of the logs.
Does this seem excessive? Probably, but my intent was to err on the side of caution, by providing MORE than what I thought was really necessary. I haven't lost any turtles yet, knock wood.
The hibernacula also serve as very shady caves for the turtles in the summer months, and all that loose soil is loaded with worms, so they use the space year round.