The Steller's sea cow was discovered in the arctic waters of the Bering Strait in 1741 by Captain Bering's stranded crew. Find this area on your map and color it black. The sea cow was much larger than manatees and dugongs. It grew up to 35 feet long and weighed up to three-and-a-half tons. This is as big as a large truck! Steller's sea cows did not have any teeth; they ate the marine algae that grows in the shallow waters of the Bering Sea. Unlike manatees and dugongs, sea cows were able to live in very cold water. They were slow-moving and had no fear of humans. This made it easy for Captain Bering's crew and other visitors to this area to kill them. Hunters ate the meat and used the tough skin for making boat covers and shoe leather. They hunted the sea cow so relentlessly that it vanished completely. In 1768, less than 30 years after it had been discovered, the defenseless sea cow became extinct.