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Federal marine specialists have concluded that Navy sonar was the most
likely cause of the unusual stranding of melon-headed whales in a
Hawaiian bay in 2004. The appearance of as many as 200 of the
normally deep-diving whales in Hanalei Bay in Kauai occurred while a
major American-Japanese sonar training exercise was taking place at
the nearby Pacific Missile Range Facility.
The report is the latest in a series of scientific reviews linking
traditional mid-frequency naval sonar to whale strandings. Sonar has
been used for decades, but it was only recently that the apparent
connection to strandings was established.
While the National Oceanic and Atmospheric Administration
scientists said they could not definitely state that sonar caused the
strandings, they said extensive study led them to the conclusion that
there was no other likely cause.
"Our analyses indicate there was no significant weather, natural
oceanographic event or known biological factors that would explain the
animals' movement into the bay nor the group's continued presence in
the bay," said Teri Rowles, NOAA Fisheries Service's lead marine
mammal veterinarian and lead author of the report.
NOAA concluded that sonar was "a plausible, if not likely,
contributing factor" to the stranding.
The Navy has said it was virtually impossible for its sonar to have
led to the Hanalei Bay stranding, and officials maintained that
position yesterday. "I think that if you look at the report, there are
just so many unknown factors at work that to say sonar was a plausible
if not likely cause is erroneous," said Lt. Commander Christy Hagen of
the U.S. Pacific Fleet in Hawaii.
The Navy is planning another major sonar testing maneuver in the
same area in July and -- for the first time -- NOAA has formally asked
the Navy to use expanded measures to protect whales from the possible
effects of its sonar.
The active sonar used by navies sends out loud pings of sound that
seem to frighten and disorient whales, especially deep-diving species
such as the beaked and melon-headed whales. The effect was documented
off Greece in 1996 and established later during naval exercises in the
Bahamas, off the Canary Islands and off Spain.
The findings have complicated the Navy's efforts to set up a
500-square-nautical-mile sonar training facility off the coast of
North Carolina. Naval officials say the sonar training is essential,
especially now that possibly hostile foreign navies have developed
diesel submarines that are not detected by the kind of passive sonar
used to follow large nuclear submarines.
Rowles said that the melon-headed stranding in Hawaii was highly
unusual, and only the second recorded in the United States in modern
times. The other occurred off Florida earlier this year, and Rowles
said NOAA is trying to determine if any naval activity occurred in the
area.
In the 2000 Bahamas stranding, a local marine biologist collected
some of the whales that died onshore and froze them for later study
-- which helped NOAA conclude that sonar was the likely cause. In
Hanalei Bay, the whales were ultimately led back to sea and one young
animal died, apparently of starvation. So there was no physical
evidence of injury to examine.
Yesterday's NOAA conclusion was based instead on the lack of other
possible causes, the unusual nature of the whale movement, and an
analysis that concluded the extensive sonar use occurred close enough
to Hanalei Bay for the whales to swim there by early July 3.
A number of environmental groups have become increasingly concerned
about the effects of sonar, and the Natural Resources Defense Council
has sued the Navy a number of times on the issue. Michael Jasny, a
senior consultant with NRDC, said the NOAA report was worrisome.
"This was by far the largest stranding of melon-headed whales ever
recorded in Hawaii," he said. "Once again, the Navy's denial has been
contradicted by the official government investigation. It's time for
the Navy to stop this needless infliction of harm."
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