Orcas' disappearance alarms scientists

[knowledge_of_self]

From: http://www.canada(dot)com/theprovince/news/story.html?id=12e09522-ba96-4f7e-9ffb-ec7b250d6898&k=87047

Orcas' disappearance alarms scientists

Ethan Baron, The Province
Published: Friday, October 20, 2006

The mysterious disappearances of orcas is alarming scientists on both sides of the border.

They fear three endangered orcas that have disappeared recently from B.C. and U.S. waters are dead.

Two other killer whales, from a less-threatened group in central and northern B.C., have vanished, and a third was killed in a collision with a boat.

The three "southern residents" -- all whales in the prime of life -- vanished this summer and fall.

"What's worrisome is . . . when we see animals disappearing prematurely," said John Ford, a research scientist for the federal Department of Fisheries and Oceans.

Researchers and whale-watching companies constantly monitor orcas off the Washington and B.C. coasts, so a missing whale is usually noticed quickly.

Twelve-year-old female K28, nicknamed Raven, left behind a nursing four-month-old calf that will die unless another nursing orca adopts it.

The three missing orcas -- Raven, 20-year-old Hugo (L71), and 34-year-old Jellyroll (L43) -- came from the K and L pods that ply the waters off southern B.C. and northern Washington.

"Individuals very, very rarely leave their group, and if they do, they're in almost all cases dead," Ford said.

Females live for an average of 50 years, while males typically make it to 30.

There are 87 southern residents, down from nearly 100 in the mid-1990s.

Two of the whales showed signs of possible starvation before they vanished, according to the Center for Whale Research in Washington state.

But Ford said wasted-looking whales could be suffering from an underlying disease.

In the "northern resident" group of about 200 orcas off the central and northern B.C. coast, three female killer whales in their prime have disappeared from three pods over the past year.

One, 12-year-old orca C21, was found floating dead July 18 near Prince Rupert, with massive bruising from an impact with a boat. That whale, along with missing whale G23, left behind a calf.

The other missing northern resident is A59, age 14.

"It's quite unusual for younger females to die," said Paul Spong, director of B.C.'s

OrcaLab research facility. "It raises a red flag."

A combination of factors threatens B.C.'s orcas, Ford said. Underwater noise and boat traffic are concerns, as is pollution. Killer whales' position at the top of the food chain means they accumulate persistent environmental toxins such as PCBs and flame-retardant PBDEs. Other mammals with lower levels of PCBs than killer whales have been found to suffer problems from the compounds.

Researchers in Washington believe toxins are making orcas more vulnerable to other problems such as inadequate food supply. Resident orcas feed heavily on chinook salmon, and although chinook counts appear typical, not everyone agrees there are plenty of salmon.

"If you talk to the fishermen, they're saying it was a horrible year," said Kelley Balcomb-Bartok, a research associate at the Center for Whale Research.

The southern residents are classified by the Canadian and U.S. governments as endangered.

Births last year raised hopes of a recovery for the population, Spong said.

"Now you have these disappearances, deaths, which sort of put things back on that declining path again," he said.

Arn't we forgetting SONAR??

 

[GRiM]

Arn't we forgetting SONAR??

Bahamas Whales Deaths Prompt Probe

AP Photo

By JESSICA ROBERTSON, Associated Press Writer

FREEPORT, Bahamas (AP) - Eight whales beached and died soon after
the
U.S. Navy conducted anti-submarine exercises off the northern Bahamas,
prompting an investigation and calls for an end to such exercises.

The Navy said Tuesday that there was no evidence to link the whale
deaths to last week's exercise testing sonar detection of submarines.

Navy Cmdr. Greg Smith said the sonar tests were scheduled only one
day
and took place from about 1 p.m. to 5 p.m. March 15 off Abaco Island.

Marine biologist Ken Balcomb of the Earthwatch environmental group
said beachings began that same day and within two days at least 14 whales
had grounded themselves on Abaco, Grand Bahama to the north, and Eleuthera
to the south. Eight died, prompting investigations by Bahamian and U.S.
scientists and authorities.

''A whale beaching in the Bahamas is a once-in-a-decade
occurrence,''
said Balcomb, an American who has been studying whales around Abaco island
for nine years.

''We will be making recommendations to the Bahamian government that
these sort of exercises be terminated,'' he said. ''The fact that it
coincides with the military exercises cannot be just coincidental.''

But the Navy spokesman said there was no evidence linking the two
events and the Navy planned to continue such tests.

''There's no suggestion we have, and no scientific data, that the
testing that we are doing was in any way linked to the current,
unfortunate
demise of great mammals,'' said Smith.

''My understanding of the actual locations would put the island
between the operations where the 'sonobuoys' were located and where the
whales eventually beached themselves,'' said Smith.

Naomi Rose of the Washington-based Humane Society of the United
States, maintained the signals could still do damage.

''These signals, depending on frequency, could travel quite a
distance
and could even wrap around the island,'' said Rose, a marine mammal
scientist. ''One could argue that they fled the area where the sonar was
being transmitted.''

Another U.S. marine biologist here to investigate, Charles Potter of
the Smithsonian Institute, said the number of whales beached is
''extremely
unusual. But he said the postmortems showed the whales had suffered no
physical damage, such as broken ear drums.

Balcomb said the mammals included several deep-water beaked whales,
goose beaked whales measuring 16-19 feet, dense beaked whales measuring
10-13 feet, baleen whales measuring up to 27 feet and some small minke
whales.

Michael Breynan, director of the Bahamian Fisheries Department, said
he was working with U.S. scientists to try to determine the cause. Breynan
said his department kept no records of beached whales but added: ''I am
not
aware of any similar incident (having occurred) in the Bahamas.''

He said further tests on the dead whales would be carried out in the
United States, a process that could take months.

Smith said the exercise was testing for upgrades of what the Navy
calls the Directional Command Activated Sonobuoy System.

The exercise involved a Navy P-3 aircraft dropping two buoys north
of
Abaco, one as close as 35 miles to the island, the other 70 to 75 miles
from
the island. One buoy emitted a sonar signal which was received by the
other,
and a submarine was moving between the two buoys.

He said the exercise had nothing to do with low frequency active
sonar, a new and controversial system that transmits sonar pulses so loud
they can match the roar of a rocket launch.

The U.S. National Marine Fisheries Service, responsible for
overseeing
all U.S. actions that could affect the environment at home or abroad, said
it approved the Navy's environmental assessment for its exercise.

Roger Gentry, coordinator of the service's acoustics team, said the
exercises shouldn't have affected the whales. ''Yet we have beached
whales.''

The service has also sent veterinarians and acoustic experts to
investigate.

Marine scientists have been expressing growing concern in recent
years
about the possible effects of man-made noises on marine mammals who rely
on
their hearing perhaps more than their sight.

''We already know from preliminary research that's been done that
there are some problems with man-made noise in the marine environment,''
said Rose of the Humane Society.

However, other experts have been quick to point out that none of the
research has been able to conclusively blame man-made noise for events
such
as the whale beachings in the Bahamas.

http://www.suite101.com/article.cfm/whales/36563
(the article is from a abcnews-report but I cant find the source, guess its been archived)