Geoscience Reference
In-Depth Information
inside perimeter of the weir, itself a giant wood and twine basket with an ingeniously designed “door” allow-
ing the unwary herring to enter it but not to exit. The net is then closed, or pursed, by a draw string at the bot-
tom, and raised, or as local fishers say, “dried up.” It is a descriptively apt phrase, for as the net is pulled up,
the water itself is seemingly transformed into a seething, electrifying mass of herring. Not only does this sil-
very bounty support many coastal communities along the Bay of Fundy and Gulf of Maine, but herring, in its
many life stages from egg to adult, is a cornerstone species for the entire marine ecosystem.
Herring consume plankton and in turn are consumed by the higher predators. Their sheer numbers—some
40 billion individuals in schools covering several square kilometers, so dense they block out the sun for divers
below— underscore their importance. Harbor porpoises' predilection for herring has earned them the sobriquet
“herring porpoises,” and the availability of young herring for breeding seabirds, such as puffins, razorbills, and
terns, is critical to the survival of their young on the breeding islands in the Gulf of Maine- Bay of Fundy sys-
tem.
Humans corral these massive shoals in weirs and seines, but humpback whales have also learned to trap her-
ring by blowing bubble nets. I have stood on a boat deck near Brier Island and looked overside as a group of
humpbacks blew a net of bubbles around a school of herring, then—lunging from below, mouths
open—exploded to the surface to engorge and swallow hundreds of the silvery morsels at once.
MOST NOTABLY, THE
ecologically unique approaches to the Bay of Fundy are a magnet for the North Atlantic
right whale, the rarest of the world's large cetaceans. Eubalaena glacialis got its unfortunate epithet as the
“right whale” to hunt because it produced large quantities of oil and conveniently floated to the surface when
killed, allowing for easy retrieval. We know that the Basques began to hunt them in the eastern North Atlantic
in the 11th century and moved their whaling operations to the New World in the 15th and 16th centuries. They
established a series of whaling stations along the Labrador coast to intercept the bowhead and right whales mi-
grating through the Strait of Belle Isle, where they harvested as many as twenty thousand of these two species.
In the era of industrial whaling, the right whales were pursued relentlessly by New England whalers for their
highly prized oil, used initially as lamp fuel and later as industrial lubricants, and their flexible baleen plates
were a precursor of plastics, employed for everything from corset stays to buggy whips. Their populations
were so decimated by the dawn of the 20th century that they became “commercially extinct,” and therefore un-
profitable to pursue. Belatedly, in 1935, the League of Nations declared it illegal to hunt them.
Although other protected whale populations, such as the Pacific gray whale, have made dramatic recoveries,
the North Atlantic right whale remains critically endangered. Records of its seasonal occurrence off Cape Cod
date to the mid-16th century. In the late 1970s, scientists working with ships' officers on ferries, in a landmark
example of “citizen science,” observed fifteen right whales in the bay—a revelation greeted with skepticism at
the time. But in the 1980s scientists determined that groups regularly returned to the outer Bay of Fundy, in
Passamaquoddy Bay and around Grand Manan Island. Research has since established that these areas in
Fundy, as well as Roseway Bank on the Scotian Shelf, are critical to the survival of the species. That survival
is precarious, as the population has been reduced to roughly 350 animals, making it the rarest of the rare.
Every summer, the females bring their calves to these food-enriched waters. It now appears that the coastal
area of the southeastern United States, between Georgia and Florida, is a major calving grounds, but these
southern waters are relatively sterile compared with the colder waters to the north. In spring, after birthing, the
right whales undertake a 2,900-kilometer (1,800-mile) seasonal migration northward, during which they stop
off at traditional feeding areas along the coast, such as the Great South Channel between Cape Cod and Ge-
orges Bank. By mid to late June, the whales begin showing up in the outer Bay of Fundy and on the southern
Scotian Shelf, where they spend the summer laying on fat.
This seemingly steady movement is marked by an underlying urgency. The females have not fed while on
the southern calving grounds, and they now need to replenish their own bodies and provide nourishment for
