"DEEP SEA CACOPHONY"
The deaths were prolonged. Slow, painful, broken gasps for air, the rise and fall of strained, unfulfilled breaths. One by one, the bodies of beached marine animals were found on shore, void of life. Eleven bodies in one month. The days and years following the deaths were muddied with confusion and mystery. What caused the deaths in harbor porpoises in Haro strait? The answer to the mystery lies in the dark, cloudy depths of the sea.
On the morning of May 5, 2003 a navy submarine, USS SHOUP, participated in an active sonar training exercise in the eastern part of the Strait of Juan de Fuca and Haro Strait in Washington State. The SHOUP was using mid-frequency sonar as part of a quarterly training exercise.
That same morning Dr. David Bain, assistant professor of psychology at the University of Washington and contractor with the National Marine Mammal Laboratory, was out on the water in Friday Harbor teaching a field methods class. Following the orca J pod on the western side of the San Juan Islands, Bain and his students noticed the group of whales turn abruptly towards the shore in an unusual location. Bain then began to hear the rhythmic pings of sonar through the hull of his boat.
Bain and his students, perplexed by the unusual behavior they were observing, documented the whale’s activity.
Cetaceans, a scientific grouping which includes porpoises, toothed-whales and baleen whales, rely heavily on sound for location, feeding and socializing. Using both high and low frequency sounds intermittently, cetaceans are able to ‘see’ where they are going. When sound waves from external forces disturb or mask these sounds, the cetacean loses awareness of its surroundings, hindering its ability to locate food and communicate.
Commercial boats, seismic sonar, cruise ships, recreational boats and navy sonar are all contributors to ocean noise. Navy sonar is a huge concern to researchers because it uses low frequency sonar. Even if a submarine is testing sonar at a distance the low frequency sound waves can travel far enough to disturb a cetacean.
"Low frequency waves travel farther; that’s why when you’re in your car and someone has music blasting you can feel [the bass] from far away," Western Washington University Professor Alejandro Acevedo-Gutierrez said.
The Navy’s official statement on the incident of the USS SHOUP was that the SHOUP’s use of sonar on May 5, 2003 was not a factor in the stranding or deaths of the harbor porpoises discovered in the following days. The report also stated that the behaviors exhibited by the orca J pod on May 5 were not out of the range of normal behavior routinely observed for the species.
"It took us a while to connect it to the Navy exercise," Bain said. "So we took notes, video, sound and a description of the behavior. At first we didn’t see any boats that could be the source of the noise, but then we observed the top of the SHOUP."
Bain and his students observed tail slaps and an unusual change in direction. The orcas also began traveling in a strange spatial arrangement. But, when the whales were no longer exposed to the sounds of sonar, their behavior went back to normal. As the SHOUP changed direction, exposing the whales a second time to the sound, the J Pod turned toward the shore again, stopping in a little bay. The pod stayed there until the SHOUP passed.
It took a while for the J pod to get back together, but all the whales survived with no measured permanent damage.
"The whales’ behavior was definitely tied to the sonar," Bain said. "The Navy people don’t have the same level of expertise on the behavior of whales, I am quite confident. They can take an individual behavior out of context and say ‘yes killer whales do that,’ but in a big package it is unusual."
Since 1996, five reports of mass strandings following Navy sonar testing have surfaced around the world. However, it is a struggle to prove the relationship between these events, the behavioral response and the beachings. Navy biologists say there is no strong evidence these beachings were related, while many researchers believe these events cannot be coincidence.
"It can be extremely frustrating that we don’t have the smoking gun; it’s all circumstantial," said Dr. Volker Deecke of the University of British Columbia. "If a whale flees from sonar and lands on a mud bank, linking it to an acoustic source is almost impossible."
Researchers argue the effect of sonar is largely behavioral and not biological, which explains why autopsies on stranded harbor porpoises have been inconclusive. In the case of the USS SHOUP, the autopsies of harbor porpoises revealed no physical damage.
"You put a once in 25-year event with the passing of a Navy boat using sonar, if that is not enough evidence for them, they may as well pack up and go home," said Dr. Lance Barrett-Lennard, a researcher at the Vancouver Aquarium.
Despite the rare orca and porpoise behavior in reaction to the USS SHOUP’s sonar, Navy biologists said they can’t be certain of the effect on marine mammals without greater evidence.
"Navy sonar is the object of much suspicion and misinformation," stated Sean Hughes, public affairs officer for Navy Region Northwest.
A careful examination of the facts and scientific evidence paints a different picture. For example, the National Marine Fisheries Service examined the remains of 11 porpoises whose bodies were found between May 2 and June 2, 2003. Some had been dead for several days, long before the USS SHOUP transited the area on May 5. In addition, other noise sources were present in Puget Sound at the time. The National Marine Fisheries Service investigation found no proof that sonar caused any of the deaths. Yet, some members of the public continue to blame sonar.
"If someone wants hard legal proof, they aren’t a scientist. We rarely have tangible proof," Barrett-Lennard said. "We work with what is probable, what is likely."
The Marine Mammal Protection Act (MMPA), created in 1972, is legislation meant to protect the safety and treatment of marine mammals in the wild. The MMPA defines harassment as any act that injures or has significant potential to injure a marine mammal or marine mammal stock in the wild, or any act that disturbs or is likely to disturb a marine mammal or marine mammal stock in the wild by causing disruption of natural behavioral patterns.
The Navy is exempt from the MMPA but not the Endangered Species Act, which includes the southern resident orca. Endangered species have ultimate protection afforded by law. Regardless of the threat sonar poses to these endangered cetaceans, the Navy stresses the importance of sonar and sonar training in the waters of the Northwest.
"Forty-one nations have diesel-electric submarines, and more than 180 diesel-electric submarines operate in the Pacific Ocean," Hughes stated. "Detecting them with sonar is a complex, highly perishable skill that cannot be completely mastered only in simulators."
As complex as the subject may seem, small measures can decrease the level of ocean noise.
"The quickest thing to do is increase the space between boats and whales," Bain said. "Not getting as close will make things quieter for whales."
Recreational boat owners can reduce their contribution to ocean noise significantly by replacing a loud boat motor with a more efficient silent one.
"We can easily make [boats] quieter, but we hear in the air so we don’t really care," Barrett-Lennard said. "The boats that are quieter above water are usually the ones that are louder underwater."
Rerouting commercial and shipping vessels through different straights would greatly decrease motor effects on marine mammals.
Some scientists think national defense is not a valid reason for sonar testing in waters of high marine mammal populations.
"You have to wonder who the enemy is," Barrett-Lennard said. "I am not aware that Osama has submarines yet."
It is a bit of an easy way out, Deecke said. Of course, national security is important, but ideally there should be a middle ground. Deecke said a healthy marine system is as important as a safe homeland.
While bodies continue to wash ashore and the deep sea discord builds, the greatest danger to marine mammals may be the ocean noise debate that remains eerily silent.
The deaths were prolonged. Slow, painful, broken gasps for air, the rise and fall of strained, unfulfilled breaths. One by one, the bodies of beached marine animals were found on shore, void of life. Eleven bodies in one month. The days and years following the deaths were muddied with confusion and mystery. What caused the deaths in harbor porpoises in Haro strait? The answer to the mystery lies in the dark, cloudy depths of the sea.
On the morning of May 5, 2003 a navy submarine, USS SHOUP, participated in an active sonar training exercise in the eastern part of the Strait of Juan de Fuca and Haro Strait in Washington State. The SHOUP was using mid-frequency sonar as part of a quarterly training exercise.
That same morning Dr. David Bain, assistant professor of psychology at the University of Washington and contractor with the National Marine Mammal Laboratory, was out on the water in Friday Harbor teaching a field methods class. Following the orca J pod on the western side of the San Juan Islands, Bain and his students noticed the group of whales turn abruptly towards the shore in an unusual location. Bain then began to hear the rhythmic pings of sonar through the hull of his boat.
Bain and his students, perplexed by the unusual behavior they were observing, documented the whale’s activity.
Cetaceans, a scientific grouping which includes porpoises, toothed-whales and baleen whales, rely heavily on sound for location, feeding and socializing. Using both high and low frequency sounds intermittently, cetaceans are able to ‘see’ where they are going. When sound waves from external forces disturb or mask these sounds, the cetacean loses awareness of its surroundings, hindering its ability to locate food and communicate.
Commercial boats, seismic sonar, cruise ships, recreational boats and navy sonar are all contributors to ocean noise. Navy sonar is a huge concern to researchers because it uses low frequency sonar. Even if a submarine is testing sonar at a distance the low frequency sound waves can travel far enough to disturb a cetacean.
"Low frequency waves travel farther; that’s why when you’re in your car and someone has music blasting you can feel [the bass] from far away," Western Washington University Professor Alejandro Acevedo-Gutierrez said.
The Navy’s official statement on the incident of the USS SHOUP was that the SHOUP’s use of sonar on May 5, 2003 was not a factor in the stranding or deaths of the harbor porpoises discovered in the following days. The report also stated that the behaviors exhibited by the orca J pod on May 5 were not out of the range of normal behavior routinely observed for the species.
"It took us a while to connect it to the Navy exercise," Bain said. "So we took notes, video, sound and a description of the behavior. At first we didn’t see any boats that could be the source of the noise, but then we observed the top of the SHOUP."
Bain and his students observed tail slaps and an unusual change in direction. The orcas also began traveling in a strange spatial arrangement. But, when the whales were no longer exposed to the sounds of sonar, their behavior went back to normal. As the SHOUP changed direction, exposing the whales a second time to the sound, the J Pod turned toward the shore again, stopping in a little bay. The pod stayed there until the SHOUP passed.
It took a while for the J pod to get back together, but all the whales survived with no measured permanent damage.
"The whales’ behavior was definitely tied to the sonar," Bain said. "The Navy people don’t have the same level of expertise on the behavior of whales, I am quite confident. They can take an individual behavior out of context and say ‘yes killer whales do that,’ but in a big package it is unusual."
Since 1996, five reports of mass strandings following Navy sonar testing have surfaced around the world. However, it is a struggle to prove the relationship between these events, the behavioral response and the beachings. Navy biologists say there is no strong evidence these beachings were related, while many researchers believe these events cannot be coincidence.
"It can be extremely frustrating that we don’t have the smoking gun; it’s all circumstantial," said Dr. Volker Deecke of the University of British Columbia. "If a whale flees from sonar and lands on a mud bank, linking it to an acoustic source is almost impossible."
Researchers argue the effect of sonar is largely behavioral and not biological, which explains why autopsies on stranded harbor porpoises have been inconclusive. In the case of the USS SHOUP, the autopsies of harbor porpoises revealed no physical damage.
"You put a once in 25-year event with the passing of a Navy boat using sonar, if that is not enough evidence for them, they may as well pack up and go home," said Dr. Lance Barrett-Lennard, a researcher at the Vancouver Aquarium.
Despite the rare orca and porpoise behavior in reaction to the USS SHOUP’s sonar, Navy biologists said they can’t be certain of the effect on marine mammals without greater evidence.
"Navy sonar is the object of much suspicion and misinformation," stated Sean Hughes, public affairs officer for Navy Region Northwest.
A careful examination of the facts and scientific evidence paints a different picture. For example, the National Marine Fisheries Service examined the remains of 11 porpoises whose bodies were found between May 2 and June 2, 2003. Some had been dead for several days, long before the USS SHOUP transited the area on May 5. In addition, other noise sources were present in Puget Sound at the time. The National Marine Fisheries Service investigation found no proof that sonar caused any of the deaths. Yet, some members of the public continue to blame sonar.
"If someone wants hard legal proof, they aren’t a scientist. We rarely have tangible proof," Barrett-Lennard said. "We work with what is probable, what is likely."
The Marine Mammal Protection Act (MMPA), created in 1972, is legislation meant to protect the safety and treatment of marine mammals in the wild. The MMPA defines harassment as any act that injures or has significant potential to injure a marine mammal or marine mammal stock in the wild, or any act that disturbs or is likely to disturb a marine mammal or marine mammal stock in the wild by causing disruption of natural behavioral patterns.
The Navy is exempt from the MMPA but not the Endangered Species Act, which includes the southern resident orca. Endangered species have ultimate protection afforded by law. Regardless of the threat sonar poses to these endangered cetaceans, the Navy stresses the importance of sonar and sonar training in the waters of the Northwest.
"Forty-one nations have diesel-electric submarines, and more than 180 diesel-electric submarines operate in the Pacific Ocean," Hughes stated. "Detecting them with sonar is a complex, highly perishable skill that cannot be completely mastered only in simulators."
As complex as the subject may seem, small measures can decrease the level of ocean noise.
"The quickest thing to do is increase the space between boats and whales," Bain said. "Not getting as close will make things quieter for whales."
Recreational boat owners can reduce their contribution to ocean noise significantly by replacing a loud boat motor with a more efficient silent one.
"We can easily make [boats] quieter, but we hear in the air so we don’t really care," Barrett-Lennard said. "The boats that are quieter above water are usually the ones that are louder underwater."
Rerouting commercial and shipping vessels through different straights would greatly decrease motor effects on marine mammals.
Some scientists think national defense is not a valid reason for sonar testing in waters of high marine mammal populations.
"You have to wonder who the enemy is," Barrett-Lennard said. "I am not aware that Osama has submarines yet."
It is a bit of an easy way out, Deecke said. Of course, national security is important, but ideally there should be a middle ground. Deecke said a healthy marine system is as important as a safe homeland.
While bodies continue to wash ashore and the deep sea discord builds, the greatest danger to marine mammals may be the ocean noise debate that remains eerily silent.
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