By Mary Landers
Ten newborn right whale calves were documented this year off the coast of Georgia and north Florida, their only known calving grounds.
That’s about half the annual average since 2000. But Clay George, who heads right whale research for the Department of Natural Resources’ Nongame Conservation Section, said researchers had been braced for worse.
“Given how few animals were seen in the Bay of Fundy last summer, we were concerned that calving numbers could be even lower. Ten is below average … but it’s not off-the-charts bad.”
Highly endangered North Atlantic right whales number about 500 individuals. They’re so-named because their slow-moving, shore-hugging habits and tendency to float when dead made them the “right” whale to kill. They were hunted to near extinction by the early 1900s.
The bus-sized baleen whales are now posting a 2.7 percent per year growth rate. Though not robust, that rate is bolstered by the fact that no whale deaths from ship strikes or entanglement in commercial fishing gear were documented this year.
George and colleagues from the DNR and other organizations did partially disentangle a whale from commercial fishing gear in February. Although not seen since, there’s hope the whale will be spotted in northern waters.
Entanglement is a leading cause of right whale deaths, and 83 percent of the whales bear scars from being entangled.
Overall, fewer deaths by collision with vessels is credited to regional ship speed restrictions, which were made permanent in December.
This year’s calf tally, which could increase if a new calf is spotted up north as occasionally happens, is not the worst in recent years. Only seven calves were documented in 2012.
If right whales slip into a protracted period of below-average calving, George said, the population will suffer. Such trends can take years to surface and can involve large-scale factors, such as climate change, that alter habitats and prey sources across the Atlantic.
Right whales feed in New England and Canadian waters in the summer, and females head south in the winter to give birth. Seasonal aerial surveys in this region ended March 31. Some whales are thought to be lingering in the South and boaters should be alert for them, cautioned Patricia Naessig, right whale survey coordinator with the nonprofit Sea2Shore Alliance.
“The main thing is — even if surveys are not going on — boaters should be cautious,” she said. “Be aware to take it slow.”
With fewer than 100 breeding females left, each potential mother is especially precious to the species’ survival, Naessig said.
“The thing people need to keep in mind is we could easily lose a few females from the population and it would cause a dramatic decrease,” she said. “You have to have four births to replace one reproductive female.”
Of the ten calves born this year, one has disappeared and likely died. It’s the offspring of a whale named Half Note who has been seen repeatedly in Georgia. At 31 years old she’s given birth six times, but only two calves, her first two, have survived.
“We don’t know if it’s something genetic or she’s not lactating,” Naessig said. “We don’t know. She’s been successful in the past with calves.”
COUNTING ON WHALES
32: Right whales other than mothers and calves seen in the Southeast this year. Most were younger than 10 years old.
20.6: Average number of calves documented per year from 2000-2013. The average since 1990 is 16.7, and 15 since 1980.
19.9: Average number of calves per year from 2000-2014.
8: Calves that scientists collected genetic samples from this season.
5 (at least): Individual humpback whales seen.
Source: Georgia DNR
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