SAVANNAH, Ga. — Scientists spotted just six calves born to right whales during the winter, making it one of the poorest calving seasons for the endangered marine mammals in a decade.
Each year researchers closely monitor the giant whales as they migrate to the warmer waters off the Atlantic coasts of Georgia and northern Florida to give birth to their young. Experts estimate only about 400 right whales remain, making each birth significant to the species’ survival.
Aerial surveys flown daily over the waters frequented by the whales turned up only six sightings of right whale newborns during this winter’s calving season from November through March.
“It was way below the average of 20 per year we’ve seen for the last decade,” said Clay George, who heads the right whale monitoring program for the Georgia Department of Natural Resources.
The Savannah Morning News reports researchers suspect one of the six calves died soon after it was born. They say its mother, identified by fingerprint-like markings on her head, in previous years gave birth to two calves that also died early.
One right whale expert said the reason for the low number of births this winter can likely be traced back to 2010. Right whales commonly spend their summer feeding season in the Bay of Fundy off Nova Scotia. But few were spotted there in the summer of 2010, leading researchers to suspect a shortage in the bay of the tiny zooplankton that are a main food source.
A food shortage in 2010 could have affect births this past winter because gestation in right whales takes a full year, said Amy Knowlton, a right whale researcher at the New England Aquarium in Boston.
“It seems like their food resources must be off,” Knowlton said.
She said she’s hoping right whale births rebound next year. In the 1990s, Knowlton said, scientists saw a calving slump when right whales produced just 11 calves in four years.
“Ideally, this is a one-year decline,” she said. “If it becomes four or five years, that’s not good. It compromises their recovery.”