Right Whale Migration

Once hunted for their blubber, North Atlantic right whales are now among the rarest mammals in the world. Only about 500 of the species exist, according to the National Oceanic and Atmospheric Administration, making them one of the most endangered marine mammals.

Right whales can weigh up to 70 tons and grow up to 60 feet. Commercial whalers christened them “right whales” because they are the “right” whale to hunt: they move slowly, are easy to chase, and carry copious amounts of blubber.

In the 19th century, American and European sailors hunted right whales in the Atlantic to the brink of extinction, killing them for their blubber — which was used as oil — and for their whalebone — the baleen plates that hang from the whales’ upper jaws and help them scoop up plankton and krill.

Today, the number of whales is dwindling, but they can still occasionally be spotted each winter, migrating south from Canada a few miles off the coast of Hilton Head Island to calve in the Lowcountry’s temperate coastal waters. A few lucky boaters may catch a glimpse of these commanding creatures, and they can occasionally be spotted from the beach.  

“The Southeast is one of the right whales critical calving grounds,” said George Albert, director of conservation for the South Carolina Aquarium. “After giving birth, the mother makes sure her calf is strong enough to move north to the feeding and nursing grounds.”

A female right whale only gives birth to a calf every three to five years. New data shows that the number of right whales dying each year — in part due to an increase in collisions with boats —is far outpacing the number being born, meaning the animals may go extinct. Scientists also discovered that climate change is affecting the whales.

“We know that the ocean is warming and becoming more acidic … temperature and water quality drive the health of habitats,” Albert said. “If you put on top of that pollution, diminishing plankton, and increasing boat traffic, you create the perfect storm. When female right whales feel stress, they produce a hormone that suppresses fertility.”

Scientists say climate change could also be the reason right whales have been vanishing from their feeding grounds off the U.S. and Canadian coasts and reappearing in other areas. It could be that they are changing their migratory routes in search of food, putting them directly in the path of ocean vessels.

Besides the lower birth rate, right whales are experiencing what NOAA calls “an unusual mortality event.” An unprecedented number of right whales died off the Northern Atlantic coast last year for unknown reasons. Scientists have ruled out disease. They say ship strikes, fishing line entanglements, ocean noise and climate change threaten the species. Some scientists fear that right whales could become extinct within our lifetime.

“Our major focus is how to remove marine aquatic debris like fishing lines and plastic,” Albert said. “We are entrenched in a culture of plastics. A major behavioral change needs to occur.”