BEAVER HABITS, BEAVER CONTROL, AND BEAVER FARMING. 7 



for building material. Such conifers as hemlock, spruce, balsam, and 

 tamarack are rarely cut, and then only for building purposes, not for 

 food. Pines are practically immune from the attack of beavers, al- 

 though I have seen a photograph of one yellow pine that had been 

 cut down by them. 



DIGGING. 



Beavers do a great deal of digging, mainly under water. Their 

 ponds are usually considerably deepened by the removal of mud and 

 earth dug up from the bottom and added to the dams and houses. 

 Large burrows begun at the bottom of their ponds, lakes, or streams 

 lead obliquely back into the banks and end in nest cavities above the 

 water level, entered only from under water. These bank burrows are 

 sometimes 40 or 50 feet long and large enough for a man to crawl 

 into. 



Extensive canals, or waterways, for floating timber and for swim- 

 ming through marshes or lowland to a food supply are dug and kept 

 open while in use. These are often 2 feet wide and 1 or 2 feet deep, 

 while old, long-used canals are even deeper and wider. (PI. Ill, Fig. 

 2.) Beavers rarely dig on the surface of the ground and never make 

 a burrow with an exposed entrance ; only under stress of confinement 

 or alarm will they even scratch at the bottom of a wire fence when 

 inclosed. I have kept an old one for three days on a lawn under an 

 inverted box and have had good-sized young for a month at a time 

 in a wire-fence inclosure with the bottom wire resting on the surface 

 of the ground. 



TRANSPORTING MATERIALS. 



The carrying done by the beavers is one of the most surprising 

 parts of their remarkable work. In transporting wood on land they 

 grasp or hold it with their strong incisor teeth, and with heads turned 

 to one side drag heavy poles or good-sized branches. A stick or 

 small branch is carried in the mouth clear of the ground or partly 

 carried and partly dragged. In the water a pole or small log is 

 usually towed by the side, the teeth being fastened into the bark near 

 the front end. At other times the log is grasped by the arms and 

 front claws, while the beaver swims powerfully at the side and 

 steers with his broad tail. 



In carrying stones, of which the dams are sometimes largely built, 

 the hands and arms are used, but as the stones are brought up from 

 the bottom of the pond and carried under water the water displaced 

 serves to reduce the weight actually lifted. Stones 5 or 6 inches in 

 diameter are commonly used. 



In carrying mud and small sticks from the bottom of the pond to 

 be placed on the clam or house the beaver does not use its tail, but its 



