Devastating Losses for Right Whales
"Devastating" Losses for Right Whales This WinterStefan Lovgrenfor National Geographic News
February 1, 2005
Four North American right whales—of the fewer than 350 left in the world—have been found dead along the eastern seaboard of the United States since November.
Researchers were especially distressed by the death of one whale, named Bolo, which was found dead off Nantucket Island on January 10. A 45-foot (13.7-meter) female, she had given birth to at least six calves, the most ever recorded for a right whale.
"The loss of a reproductive female, especially one as successful as Bolo, is a blow to this population that is just hanging in the balance," said Moira Brown, a right whale expert at the New England Aquarium in Boston, Massachusetts.
Brown says the animal is "on the brink of extinction."
Big and Slow
The right whales were hunted for centuries. They got their name from whalers who considered them to be the "right" whales to kill because of their large size, coastal distribution, and slow swimming speed. Unlike other whale species, the stocky right whale also floats after death.
The North American right whale, which is closely related to the North Pacific and South Atlantic right whales, was almost hunted to extinction in the mid-1700s. The hunt was eventually banned in 1935.
Today they run the risk of getting hit by a ship or entangled in fishing lines. The whales summer in the Bay of Fundy, off Nova Scotia. Pregnant females migrate south to waters off the U.S. state of Georgia in the winter to give birth. Researchers don't know the winter locations of most of the other types of right whales.
In November a pregnant right whale was found off the Virginia coast, possibly a victim of being struck by a ship. In December another whale was found dead 86 miles (138 kilometers) east of Nantucket.
On January 12, only two days after Bolo's death, another female right whale, named Lucky, was found dead off the coast of Georgia. Lucky, named for scars she received from a previous ship-strike, was pregnant with her first known calf.
"To say the last 12 months have been devastating to right whales is an understatement," said Regina Asmutis-Silvia, a biologist for the International Wildlife Coalition in East Falmouth, Massachusetts.
Right whales are so rare that scientists who study them know them by name. Each whale has a distinctive pattern on the top and side of its head. The patterns are made up of rough, raised patches of skin called callosities. Scientists use the patterns to distinguish individual animals.
Scientists photograph right whales from boats and small airplanes. They also track the whales' DNA by obtaining small skin biopsy samples from each whale. From these samples, researchers can learn the paternity of calves.
The information is used to develop a genetic profile of each right whale as well as a family tree for the population.
Human-Induced Mortality
A National Oceanic and Atmospheric Administration plane spotted Bolo's lifeless body floating 78 miles (126 kilometers) east of Nantucket Island, located off Cape Cod, Massachusetts.
Researchers say Bolo was more than 23 years old, because they first saw her when she had calved in 1981. She gave birth at least six times, the last known time in 2001.
How Bolo died is still unknown, but it is possible that a ship struck her. Ship collisions and entanglement in fishing gear now make up 50 percent of known right whale deaths.
"The habitat they live in is extremely busy with human activities. That is why we are calling this the urban whale," Brown said. "[It is] whale that is exposed to all of the marine activity along the East Coast, as well as exposure to all of the contaminants that humans dump in the water."
Reason to Cheer
There is some good news, however.
Calvin—a right whale that was orphaned at age 8 months in 1992, when her mother was hit by a ship in the Bay of Fundy—recently gave birth to her first calf.
Brown, who named Calvin back in 1992 before she knew the whale was a female, says the name stuck, "because she was a precocious little whale." Brown now hopes that aggressive efforts will be taken to protect North Atlantic right whales.
"We have been successful in moving the shipping lanes away from the main concentration of right whales in Fundy, which is where Calvin's mother was killed. But there remains much more work to be done with shipping interests in the United States," Brown said.
"If one good thing can come out of all these whale deaths, it would be the speedy implementation of conservation measures throughout their range to reduce the impact of human activities on this population," she said.
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