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NO. FALMOUTH, MA - The news from northern right whale calving grounds off Georgia and Florida this winter is excellent. A total of 19 new calves had been born as of mid-February, compared to only a total of 10 in the three previous years.
The last time the right whale population experienced such a baby boom was in 1996 and 1997, when 21 and 19 calves were born. The class of 2001 could have a few more additions before it's over, too.
A half-dozen or so females could still potentially give birth, and, according to Scott Kraus of the New England Aquarium, it's not unheard of for the calving period to run into late February.
"There could be more before we're done," Kraus said.
The news was not all good, however. One calf not counted in the total was killed, apparently as the result of a ship strike, late in January.
The National Marine Fisheries Service (NMFS) also cautioned that the population's increase "is only one small step toward recovery" of the whales, which are often described as the most endangered on earth.
Still, the surging birth rate was a tremendous relief to scientists who study the animals and others concerned about their status. Last year, only one new whale was born.
Scientists are not sure why the birth rate fluctuates the way it does. One possible factor is the variation in food supplies, with births increasing in the years following an increase in available food and declining after years of less abundance.
If, as some expect, food availability is the operative factor in right whale reproduction success, then the prognosis for the whales might not be so bad.
"These are long-live animals," said Phil Clapham, a NMFS whale researcher. "If the problem is a variation in food, the females should be able to survive year-to-year fluctuations and produce enough calves in good years to slowly rebuild the populations -- if we can reduce the deaths from entanglement and ship collisions.
Genetics work
During the Jan. 26-28 Massachusetts Lobstermen's Association annual meeting, Moria Brown of the Center for Coastal Studies (CCS) in Provincetown gave a fast-paced, fact-filled talk on recent developments in the study and monitoring of right whales.
While inbreeding is often suggested as the reason why the right whale population has failed to rebound, Brown said that recent genetics work indicates it's probably not a factor.
"Geneticists believe that the right whales took a big hit in the 1500s (when Basque whalers worked these waters). The population has been held down since either through hunting or ship collisions," she said.
"Geneticists now believe that inbreeding is not a problem because the population has been down for so long that the bad genes were probably purged long ago," Brown said.
Aerial surveys
She also described the aerial survey work conducted by CCS and the Massachusetts Division of Marine Fisheries in the Cape Cod Bay critical habitat area from January to mid-April during the last few years.
About two days a week, the survey plane takes off and flies east to west and back over the bay along track lines one-and-a-half miles apart. The plane flies 750' above the surface of the water at 100 mph.
Survey observations indicate that the whales spend most of their time in the bay feeding underwater from 3'-10' below the surface all the way to the bottom, Brown said. For reasons unknown, the whales appear to depart the bay "rather abruptly" in mid-April.
How they die
Since the 1970s, right whale researchers have documented deaths of the animals. The cause of death is not always known, but 16 have been attributed to ship collisions and three to fishing gear entanglements.
Brown added that 62% of the whales show scars from entanglement, but that "very few" scars from ship collisions have been documented. This leads some to believe that ship collision injuries are more lethal than entanglements.
There's also news on why the whales may be so vulnerable to ship strikes.
Brown said that research suggests the whales may not hear ship engines, possibly because they may hear different frequencies than people do, "like we can't hear a dog whistle."
She said an effort is currently underway to see if Canadian authorities and the shipping industry would be willing to consider moving the major shipping lane that goes through the Bay of Fundy -- right through right whale habitat.
Here in the US, NMFS is working on educating the shipping industry and trying to get shippers to use voluntary measures to avoid collisions with whales.
"It's a hard thing. No agency permits these ships," Brown said.
Lorelei Stevens
