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The articles below were taken from
the Saint John Times Globe March 30/99
Eventual
Extinction Scientists have a grim new prediction
for the Bay of Fundy's right whales
By JOHN CHILIBECK Times Globe
staff writer
When Laurie
Murison hits the water this summer, she'll be keeping her eyes peeled for three
precious mammals. As managing director of the Grand Manan
Whale and Seabird Research Station, Ms. Murison spends the better part of her
summer looking for whales in the Bay of Fundy. An
important part of the research is identifying and photographing the northern
right whale, considered the most endangered large whale species on the
planet. Scientists estimate that only about 300 of the
baleen behemoths are left worldwide, and, according to a recent study, their
numbers are mysteriously declining. But the latest news
is even worse: Whale researchers in Florida have spotted only three newborn
calves this season. That's cause for
alarm. "It is of great concern," said Ms. Murison. "So
far, this has been the worst year ever for identifying newborn
calves. During the winter months, most right whales
congregate off the continental shelf of Georgia and Florida, where the females
give birth to calves as large as two adult humans. The whales then migrate
north in the spring, chasing plankton until they reach the Scotian Shelf and
the Bay of Fundy toward the end of June. Since 1980,
researchers along the Eastern seaboard have been photographing the whales and
sending the results to the New England Aquarium, which keeps a large database.
Each animal has unique markings, scars and callosity patterns, so there's
little trouble distinguishing the whales from one another, and the photographs
can be used to track an individual whale for years. On
average, about 11 newborn calves have been spotted each year over the last two
decades. Sightings vary from year to year, but the lowest number photographed
to date was five newborn calves in one year.
Unfortunately, fewer and fewer young ones have been turning up of late. In
1996, 22 newborns were identified. In 1997, the number dropped to 18. Last
year, only 6 were photographed. The decline has
researchers scrambling to find answers. Hal Caswell, a
senior scientist with the Woods Hole Oceanographic Institution in
Massachusetts, recently completed a study on the survival probability of the
right whale. Mr. Caswell's research team did not focus
primarily on birth rates, but they used data from other scientists who had.
What they came up with was frightening. In the early
1980s, mature females were giving birth to a calf on average every 3½
years. Today, that interval has increased to five years a disturbing trend that
scientists have not been able to adequately explain. Mr.
Caswell and the co-authors of the Woods Hole/ University of Massachusetts
study, Masami Fujiwara and Solange Brault, used the New England database and
sophisticated computer models to estimate the survival probability of the
whales. They discovered that the whales are dying at a
rate of 18 per year, whereas the birth rate is only 11 or 12 animals per year
(the study only went up to 1996). The authors concluded that if trends
continued, the right whale population would be extinct in 191
years. Prior to this research, many scientists believed
that like other whales, most notably the humpback, the right whale was slowly
on the rebound after being driven nearly to extinction by whalers at the turn
of the century. However, according to Mr. Caswell's
figures, the population was growing slightly until 1990 or 1991, when a slow
decline set in. "Three calves being spotted in Florida -
that is low," said Mr. Caswell about the latest reports. "People are a little
worried about it. It's not a good sign." Autopsies of
dead whales over the last 20 years show that 30 per cent of the deaths were
caused by ship collisions, and another 8 per cent were caused by entanglement
in fishing gear. That's why many whale researchers think human-caused mortality
should be targeted to ensure the survival of the species.
The trouble is, whales are elusive creatures, even in death. Only about 30 dead
right whales have been found in the last two decades, and some have been so
badly decomposed, it's difficult to tell what killed
them. "Most of these whales when they die, they just
disappear," said Mr. Caswell. "It's a big ocean. A dead whale seems like a big
thing if it washes up on the beach, but more often than not, they just
disappear." Even their migratory patterns are slightly
suspect. Up until 1993, the whales seemed to have preferred the summer feeding
grounds off the Scotian Shelf, with only 50 to 60 of the animals swimming into
the Bay of Fundy each year. Now up to half the total
right whale population visits off-shore New Brunswick each summer and fall. The
whales have been spotted as far north as Iceland and the Gulf of Mexico. And
there are suspicions that the whales may have another winter calving ground,
further out-to-sea from the continental shelf of Georgia and
Florida. Scientists cite everything from pollution, to a
depleted food supply, to a change in water temperature and currents for the
shifting patterns. Given the complexity of the creatures, it could be a
combination of all three, or something completely
different. What does it boil down to for researchers?
Tracking the creatures is a somewhat shaky science.
Still, Mr. Caswell believes his study used enough rigorous statistical
estimates of survival probability to prove the whales are, indeed, on the
decline. Nor is he an alarmist. Despite the negative
findings, he remains cautiously optimistic about the whales' future.
"If things were to remain the way they are now, then it
would be time for pessimism, the whale would be on its way out. But our results
suggest that you don't have to eliminate all fishing and all shipping in order
to save the right whale. If you could get conditions back to the way they were
in the early 1980s, which isn't all that long ago, the whales would do quite
well. Under the conditions back then, they actually had a nice, positive rate
of growth. " Ms. Murison also believes cutting down on
accidental ship strikes and entanglements in fishing gear would go a long way
to increasing the right whale's chances of survival.
About half of the right whales identified in photographs have wounds or scars
on them from brushes with ships. It's not a far stretch, then, to assume a lot
of whales are killed by large, fast-moving vessels. . "What we can't do is
actually go in and physically manipulate right whales," she said. "We can't
throw them in an aquarium and say, okay, reproduce, and we'll build a stock.
It's not going to happen. They're too big, and there are no facilities
available." Instead, Ms. Murison is counting on rescue
teams to free the whales when they become entangled, and ships to slow down
when they are cruising through the whale's migratory paths.
In the United States, plans are already afoot to protect the
whales. New federal regulations, which come into effect Thursday, ban
gillnetters and lobster boats from using certain types of gear, and place
moratoriums on fishing in some areas, such as Cape Cod Bay and South Bay
Channel, during the right whale season. Beginning in
July, the U.S. government will also require large vessels entering areas of
known right whale concentrations to report their location and course to marine
authorities, who will try to make sure the vessels don't run into any whales.
Here at home, the Saint John Marine Communications and
Traffic Services Centre keeps an eye on the whales when they show up at the end
of June. During the whale season, it radios every major vessel entering the Bay
of Fundy to keep a look-out for the underwater giants.
The Department of Fisheries and Oceans is also purchasing equipment and setting
up a training program this spring so that volunteers, be they fishermen, whale
watching guides or researchers, can help save the whales when they get caught
in fishing gear. Jerry Conway, the DFO's marine-mammal
adviser in the Maritimes, said the program will be up and running by June. The
department hopes to attract 10 volunteers from New Brunswick and 10 volunteers
from Nova Scotia, who will be trained in the St. Andrews and Digby areas,
respectively.
Whale team:
Change Fundy fishing methods
By ALAN WHITE Telegraph Journal
staff writer
With entanglement
in fishing gear posing one of the greatest threats to the endangered right
whale, a team struck to suggest ways to ensure its survival is suggesting that
officials consider periodic fishing closures in areas of the Bay of Fundy where
whales would be most at risk. The recommendation is one
of 43 arrived at over the last 18 months by the right whale recovery team
headed by the Department of Fisheries and Oceans and the World Wildlife Fund,
which includes scientists, and representatives from the fisheries and whale-
watching sectors. The recovery team's recommendations
are scheduled to be made public on Thursday by DFO, after which it will accept
public feedback. ,Two of the five primary recommendations are aimed at reducing
the risk to whales through collisions with ships and through encounters with
fishing gear. One recommendation of the recovery team is
to consider closing fishing areas at times when right whales are most likely to
be in that area, thus reducing the amount of overlap, in time and in space,
between fishing gear and right whales. However, such a decision would not be
taken lightly. "Actions that limit fishing activity need
to be well-justified and accommodate as much as possible the needs and
aspirations of fishing communities," states the committee in its draft report,
a copy of which was obtained by the Telegraph Journal.
More than half the living population of right whales show wounds or scars from
encounters with fishing gear. Many whales tow buoys, nets or lines for months
or years. Another recommendation is to investigate the
use of modified fishing gear, such as breakaway or biodegradable lines, to
reduce severe whale entanglements or entrapments. Much study has already been
done in that area in the U.S.
Whale tours may
Unite over Concerns
By JOHN CHILIBECK Times Globe
staff writer
Whale watching
companies in the Bay of Fundy want to start watching
themselves. The idea for a whale watching association came
up yesterday at a first-ever meeting between tour operators, conservationists
and civil servants from both sides of the Bay, held at the Union Club in Saint
John. Over the last five years, whale watching has
exploded in the Bay. Today, as many as 60 companies offer whale-watching tours
in the West Isles, Grand Manan and southwestern Nova Scotia.
There are still no regulations governing the whale watching
operators other than federal laws that apply to all boat owners.
One major concern that came up at the forum was the growing
number of pleasure seekers in their own vessel who harass whales.
Most tour operators signed a code of ethics last year which
ensure they don't disturb the whales. It includes provisions such as not
chasing or herding the animals and keeping a distance of at least 100 metres.
But operators from near the Maine border report that
growing numbers of smaller vessels from the United States are coming into
Canadian waters and pursuing the whales. "We call them
cowboys, these chasers," said Marc Witteveen, the owner of S.V. Corey in St.
Andrews. "You're supposed to sit and watch, and let the whales come toward you.
It takes the romance away when you have 20 boats surrounding one whale."
Jerry Conway, a marine-mammal adviser with the
Department of Fisheries and Oceans, said his department investigates all
reports of whale harassment, but is often stymied. judges often demand proof
that a whale was harmed, and DFO has abandoned two cases.
The operators will meet again in late October to discuss
the rules for a new association.
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