A gray whale baby boom appears to be under way along Alaska's arctic coast. Scientists tracking marine mammals in the Chukchi Sea report an unprecedented number of sightings of gray whale calves in July.
The biggest number previously counted was 18, reported in 1982 and 2011. Those tallies were for the full season, which runs from late June/early July until October. But 57 cow-calf pairs were recorded between July 1 and July 26 this year, according to the federal Alaska Fisheries Science Center.
"There's the potential that some of those are repeat sightings," said Megan Ferguson, project coordinator for the Aerial Surveys of Arctic Marine Mammals Project in a phone interview from Barrow. "But the fact that we're seeing a five-fold increase makes me think that it is a real increase."
Wayne Perryman, a researcher with the federal Southwestern Fisheries Science Center in La Jolla, Calif, said California numbers for young gray whales are also high.
"This was a big calf count year," he wrote in an email, "(with an) estimate of about 1,000 calves, so there should be a lot of them everywhere."
The grays make seasonal trips from the Chukchi Sea to Mexico. Their well-documented travels make them a popular attraction for whale spotters who hit tour boats from Baja to Alaska when migrations take place.
Julie Speegle, a spokesman for the National Oceanic and Atmospheric Administration in Alaska, cited agency estimates that put the entire Eastern North Pacific gray whale population at between 18,000-21,000 animals. Adults are about 45 feet long and weigh 35 tons; babies are born weighing just 1,100 pounds and stretching 15 feet.
The Atlantic population was wiped out hundreds of years ago, Ferguson said. But the Pacific grays are no longer classified as endangered.
Data for previous sightings in the Chukchi Sea was collected between 1982 and 1991 and then ended. No calves were spotted in 1991 and only one was seen when surveys resumed in 2008. Ten were seen the following year and none in 2010. Ferguson noted that in the 1982-91 survey period, the whales were consistently seen in both coastal and offshore shoal areas. However, she said, "Since we started again, we still see them in the coastal areas but not in the shoal areas."
The calves and their mothers were all found within 30 to 40 nautical miles of the Alaska coast between Barrow and Point Lay, about 200 miles southwest. "That's where we typically find the cow-calf pairs," Ferguson said. "It's extremely rare that we see a gray whale east of Point Barrow."
Data in Alaska has not been collected for the past week because researchers have been stuck on the ground due to bad weather.