Right whales are probably old enough to mate around 8 years old. Females are pregnant for about 13 months and only get pregnant approximately every three to five years. Calves are born able to swim. A mother and her calf form a very close attachment. It is believed that right whales live at least 50 years.
Right whales die of natural causes and are sometimes preyed upon by killer whales .
Right whales may also be harmed by pollution, ship strikes, or entanglement in fishing gear. Books and the world wide web are excellent places to learn more about marine mammals. Books Leatherwood, Stephen. Reeves, Randall R. Foster, Larry. The Sierra Handbook of Whales and Dolphins .