|Our large whales have been depleted by overfishing which began in the 18th century
and continued through the 20th century. All have been reduced to startling numbers
and have been placed on the endangered species in 1973. The fin, humpback, right,
blue, Bryde’s and sperm whales are all considered endangered, as over 2,000,000
whales were killed from 1700 to 1900.
Scientists suggested that whale numbers could be evaluated using a sound system to
track and count the number of whales in the ocean. Each species of whale has a
different call which means each species could be counted separately. The blue whale
does have variations in their calls meaning that it is more difficult to assess their
numbers. The fin, humpback and gray whale numbers can more accurately be
With the end of the cold war and the subsequent willingness of the US government to
allow dual use of some military assets, a unique opportunity arose to use the US
Navy's SOSUS (Sound Surveillance System) underwater hydrophone network to
detect and track whales.
Biologists welcomed this opportunity, and found in SOSUS an unprecedented tool to
detect blue and fin whale calls over long distances in the North Atlantic and North
Pacific basins and to track individual whales that produced atypical calls. In the
North Pacific, the seasonal detection of endangered blue and fin whale calls, using
SOSUS, provided a means to correlate call occurrence with habitat features in
remote areas off the Kamchatka Peninsula and to investigate whale response to ocean
climate variability off California
The Pacific grays were thought extinct until 1974, when Robert Brownell Jr., now
with the National Oceanic and Atmospheric Administration (NOAA) in Pacific Grove,
California, established the existence of a small population of surviving whales, close
cousins of the Eastern Pacific grays that were rescued from extinction off California.
Hard on the heels of this rediscovery came another revelation: massive oil and gas
deposits near Piltun Bay, where the whales feed before migrating to the South
Pacific each autumn. Under a 1993 U.S.-Russian environmental agreement, SE and
ENL help pay for studies on how development of the petroleum reserves might affect
the mammals. Since 1997, $4 million of funding from the two companies, along with
money from nonprofits and a U.S.-Russian research program, has nourished a raft of
Data in the open literature raise disturbing questions. For instance, findings from
Brownell, NOAA colleague David Weller, and a Russian team led by Alexander Burdin
of the Kamchatka Institute of Ecology and Nature Management suggest that the
Western grays are under duress. Based on photographic tracking of the pod, they
estimate there may be as few as 100 individuals, of which only 17 are capable of
bearing calves. Whales are among the top five most endangered whale species in the
world. Their condition seems to be deteriorating with many whales having lost weight.
With the whales on the edge of extinction any disruption of normal feeding patterns
is of concern. Biologists have noticed just such a disruption in 2001, when they found
that the distribution of whales in the feeding grounds had shifted significantly during
6 weeks of seismic testing by ENL 4 kilometers away.
In the Piltun Bay area biologists watched as the whales were forced to leave during
their crucial fattening period and many whales were later spotted in another feeding
area further offshore.
About Gray Whales
Weight: Up to 35 tons.
Size: Adults reach 40-50 feet. Calves are 16-feet-long at birth.
Description: Mottled gray and encrusted with bamackles on the back, head and
lower sides of jaw. Coarse bristles, called baleen, line the mouth and are used to
strain tiny shrimp and plankton. Instead of dorsal fins, nubs are found along the back.
Range: Although it once inhabited both the Atlantic and Pacific Oceans, the gray
whale is now found only in the northeastern Pacific. The whales spend May through
November in the Bering Sea before moving down the Pacific coast to winter in Baja
California--the longest known migration of any mammal.
Background: Gray whales were nearly hunted to extinction by the end of the 19th
century. As a result of protection by the US, Canada and Mexico, the whales have
partially increased in number. Russian whalers continue to kill 179 gray whales each
year off Siberia through a waiver granted for "aboriginal" hunting -- a thinly veiled
excuse for continued harvesting, since whale meat is not used by natives, according to
Russin sources. Instead, it is sold to Siberian fur farms and used to feed minks and
Hoare, B. Eyewitness: Endangered Animals. 2010
Hoyt, E. Whale Rescue: Changing the Future for Endangered Wildlife. 2005.
Simmonds, M. P. Whales and Dolphins of the World. 2005.