Many species of birds migrate in winter. animals including bats, ground squirrels, and woodchucks hibernate in winter. which of the following do hibernation and migration have in common? a. they both occur as a way of surviving when there is little food available. b. they both involve traveling from a cold climate to a warmer climate. c. they both involve the animal increasing its fat stores during the summer months. d. they both occur once per year and last for at least six months of the year.