Mammals Like Us! Click on a picture to see a bigger one. Whales are mammals because . . . They give birth to live young (rather than laying eggs). The babies feed on mother's milk. Did you notice that mom and the kid stick close together? Baby gray whales depend on mom for a long time — much like human babies do! A calf spends most of its time swimming alongside its mother. Mom lends a hand (really, a fin!) when the kid needs it. In the middle picture, the baby that had been resting on mom just slid off her back! The calves nurse for around 6 months and drink up to 50 gallons of milk each day! The milk contains so much fat that the calves can gain 60 to 70 pounds a day. How do you think this helps keep them alive during their cold trip north? This Season Teachers Kids Orientation Registration Search Copyright 1997-2008 Journey North. All Rights Reserved. Questions or comments? Contact us.