Owls Aren't Wise and Bats Aren't Blind Read Free Page B

debris would soon fill the lodge. Although bark represents their primary winter food supply, beavers also supplement their diet with the thick, tuberous rootstocks of pond lilies, at least in those ponds where these plants grow.
    Like a number of other wild creatures, beavers mate for life, but that doesn’t mean what most people seem to think it does. The common perception of lifetime mating in the wild is that the death of one partner relegates the survivor to a single existence for the remainder of its life. That’s not the case at all. Like many humans, a wild animal that normally mates for life will, after the death of its mate, seek another.
    As previously noted, beavers live in a colony that consists exclusively of a single beaver family. Each colony begins with a mated pair of young beavers. After the pair have constructed dam and lodge, and laid down a winter’s food supply, they breed during the winter. After a gestation of about ninety days, the young, called kits, are born in the spring. There are usually three to five kits in a litter, and occasionally more.
    The young remain with the parents through the winter, and the following spring the colony is enlarged by a second litter of kits. The colony now contains the parents plus the offspring from two successive years. All of the beavers in a colony share the work of maintaining the dam and lodge, and cutting and storing the winter food supply.
    Although a number of myths have grown up concerning beavers, the phrase “busy as a beaver” most assuredly isn’t one of them. Beavers labor intensively during the warm months, preparing for the long winter to come. Constant diligence and great effort are required to ensure an adequate and secure habitat, as well as an ample winter food supply. Only when the pond finally becomes icebound can the beavers relax and enjoy the fruits of their labors.
    Big changes occur during the colony’s third spring. As another litter of kits is born, the young of two years before either leave the colony voluntarily or are driven out by their parents. These “dispossessed” beavers must now seek new territory, find mates, and begin new colonies. Stark evidence of this springtime diaspora is often visible in the form of dead beavers killed by automobiles as they try to cross highways.
    Thereafter, for the life of the colony, a new set of kits will be born each spring, and the two-year-olds will either set out on their own or be driven out. Although this system may seem harsh, it’s necessary for the colony’s survival. Without this annual dispersal, a beaver colony would soon become impossibly overpopulated, to the detriment of all.
    The manner in which the dispersed two-year-olds find mates is an interesting one, worthy of a bit of exploration. The beaver’s genus name,
Castor,
comes to us through Latin from
Kastor,
the Greek name for the beaver. Eventually,
castor
even became a term for a beaver hat during the heyday of that article of apparel.
    Of greater relevance in this instance is that beavers of both sexes secrete an oily, pungent substance that’s also known as castor. This rather malodorous liquid is produced by a pair of glands in the inguinal region, close to the anus. Beavers are highly territorial and have a well-developed sense of smell, so as soon as a young beaver finds a suitable site for a dam, it marks the boundaries of its territory with what are called
castor mounds.
    Castor mounds are piles of mud and debris carried by the beaver with its front paws. These heaps are normally placed close to the water, and the beaver deposits castor on them. Such mounds can grow into sizable structures, especially where the territories of two or more colonies intersect. In that situation, a beaver from one colony will try to cover the scent of another colony by heaping more material on the mound and then depositing its own castor. As this “castor duel” continues, the mounds can sometimes grow to waist height on a