Give Warnings With Their Tails 
Next they started to save 
food for the winter. They 
cut down many small 
poplar trees with their 
sharp, chisel-like teeth, 
and cut off the branches. 
Their keen eyes and ears 
told them of danger, and 
they warned each other 
by slapping the water 
with their tails before 
diving out of sight. 
When danger was past, 
they carried the wood 
under water and worked 
it into the sides of the 
house to use for food 
when the pond was all ice. 
