(AP) -- Right whales have plenty to celebrate this Mother's Day - the sea moms gave birth to a record 39 calves this spring.
The New England Aquarium said Friday that the birth surge breaks the old record of 31 and shows much improvement from 2000, when only one calf was born.
Each birthing season is important because right whales number fewer than 400 and are among the most endangered whales in the world.
Having a calf is no easy task for the 50-foot-long whales, who give birth off the Florida and Georgia coasts.
The moms travel nearly 1,000 miles down the East Coast to warmer waters for their babies, who weigh roughly 2,400 pounds at birth. And the moms can lose up to 30,000 pounds in the first year they are nursing.
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