The most anticipated day of my year is “BDay” — the first day when beavers are spotted on the ice in spring after emerging from small openings in the water in front of their lodges after a long winter of confinement. With the rest of the pond still covered in ice, the beavers remain spatially confined but are free to roam within their winter lodge and below-ice habitat.

First, one of the adults emerges — much like a sentinel — and then the rest of the family follows in kind, except for the newborn kits who remain inside the lodge for several more weeks. In time, the entire pond becomes free of ice and spring begins anew.

Spring emergence is most often documented in hibernators — species that experience noticeable changes to their metabolisms, core temperature and behaviour in winter. As seasonally confined non-hibernating mammals, beavers remain active under the ice throughout the winter.

Also, unlike true hibernators, maintaining a normal body temperature allows beavers to mate during their winter confinement and give birth to their kits before emerging in spring. However, as with true hibernators, the timing........

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