ATOC Study Begins. Scripps Institution of Oceanography scientists were to begin the first sound transmissions in the Acoustic Thermometry of Ocean Climate (ATOC) program, to study how the sound transmissions might affect marine mammals.
A total of three dead humpback whales were spotted off the Farrallon Islands, in the broad area around the ATOC sound source. The first was found 3 Nov., and buried without autopsy. The second two were found floating 9 Nov. These two were lost somewhere outside Santa Cruz; one was last sighted Monday, Nov. 13, I believe. The ATOC sound source was first turned on during the night of Oct. 28, and was broadcasting on 12 further occasions between 28 Oct. and 4 Nov. Unfortunately, the Scripps oceanographers in charge of the ATOC project had neglected to clearly notify the ATOC marine mammal scientists that the source would be broadcasting, which was in violation of agreed-upon scientific protocol.
Information on whether anyone has spotted humpback whale carcasses or any other dead marine life near the Farrallons would be highly appreciated. Has anyone made any observations of toxic algal blooms in this area? Any comments (stranding patterns this time of year, etc.) would be welcome.
Three humpback whales found dead at Stinson Beach and the Farallon Islands last week have caused further delays in a controversial undersea sound experiment off the coast at Half Moon Bay, scientists said yesterday.
The sound transmissions by researchers from the Scripps Institution of Oceanography at the University of California at San Diego were intended to gauge whether a larger, $35 million program to measure global warming would injure or disrupt marine mammals. While preparing the experiment, scientists tried out the device that emits sound waves into the Pacific. Scripps does not believe that procedure is linked to the whale deaths, but the subsequent experiments were nonetheless called off at the request of the National Marine Fisheries Service. The agency has asked that no tests take place until it has completed an investigation of what killed the leviathans.
``The operation of the sound source during the installation to test its performance is not related to the whale deaths,'' said Andrew Forbes, a Scripps researcher. But, he added, ``because the time of deaths of the whales and the exact cause of their deaths is not known, we are taking a very conservative position and will not operate our program until we receive a report from the NMFS.''
Testing of the sound program's effects on marine mammals is led by Dan Costa, a researcher at UC Santa Cruz. Costa had already called off a November 9 test because bad weather blocked an aerial survey of an underwater mountain 48 miles offshore. The aerial test must be conducted within 48 hours before the underwater tests begin. Then, the research ship used to monitor marine mammal behavior during the tests became unavailable, further delaying the transmissions.
Scott Anderson, an Inverness field biologist, observed all three dead whales last week. He said he went out into the Pacific off the Farallones in a small boat and found two that ``were bloated, floating high in the water, looking like little islands, with no apparent wounds that would indicate how they died. They did not have injuries such as they would if they had been struck by ships.''
He said ``it is unusual for a group of baleen whales to die like this all at the same time, especially at this time of year.'' A humpback is a type of baleen whale. However, he discounted any connection between the sound transmission program and the whale deaths. Other naturalists said the whales could have been poisoned by toxins in the fish they ate or the buildup of potentially harmful ``brown algae'' in the water.
The transmission experiment is designed to learn whether increases in the rate of global warming can be detected by using underwater sound waves to measure long-term changes in ocean temperature. The project would place noise emitters 3,000 feet under Pacific waters off Half Moon Bay, linked by a one-inch diameter power cable to the shore. Although some experts say the sound emissions would be no louder than those produced by passing ships, strong objections to the program from environmental groups forced researchers to accept a range of conditions, including a stipulation that the experiment be substantially modified or halted outright if it is found to harm marine life.
In a similar development, Exxon Corp. began a seismic survey off Santa Barbara yesterday, using sound waves to assess oil and gas reserves in the 126-square-mile Santa Ynez field, the largest offshore reserve in contiguous U.S. territory. Environmental groups and the state Coastal Commission had threatened to block the testing, saying sound waves could disrupt the migration of gray whales and adversely affect more than 34 other marine species. But a compromise permitted Exxon to go ahead with the probe on the condition that the emissions be halted if marine mammals enter protected areas around the transmitters. Bruce Tackett, a spokesman for Exxon at corporate headquarters in Houston, said yesterday that a trial run Friday resulted in a decision to begin the test at midnight Monday.
In diving at Bodega Marine Lab and Salt Pt. (both areas north of the Farallones) during the Halloween week there was indeed a very large Plankton (dinoflagellates ?) bloom. This water mass was traveling north at the time so that it likely originated within the Gulf of the Farallones and was traveling north as a buoyancy current of was advected onhsore from an offshore source. My guess is the former. There was also a rainstorm that week. No idea whether they were toxic algae.
Officials with the National Marine Fisheries Service have reported that they believe it is unlikely that the deaths of three humpback whales off Half Moon Bay, Calif., are linked to acoustic engineering tests conducted as part of Scripps Institution of Oceanography's Acoustic Thermometry of Ocean Climate (ATOC) program and have authorized the project to start operations.
The California Marine Mammal Research Program (MMRP) component of the project, intended to study whether underwater sound signals might have any adverse impact on marine mammals, was scheduled to begin Nov. 9. Upon learning a humpback whale had been discovered dead in the region, however, project scientists placed the program on hold as a precautionary measure while seeking advice from the National Marine Fisheries Service (NMFS) and the MMRP Advisory Board.
Following an extensive review, NMFS officials stated in a letter dated Nov. 30 that "the Scripps Institution of Oceanography may proceed with initiation of the MMRP." Accordingly, the program is to start as soon as weather permits.Based on available data, the National Marine Fisheries' Southwest Region Office (NMFS-SWR) in Long Beach, Calif., was unable to determine the cause of the death of the three whales, which were discovered in the San Francisco area between Nov. 4 and Nov. 9. However, agency officials said they did not believe tests of the ATOC sound source were responsible for the whale deaths.
The California Coastal Commission voted to ask NMFS to reopen its investigation of the three humpback whale deaths after ATOC researchers were reported to have stated that determining cause-of-death to marine mammals in the ATOC project area is not part of the ATOC project design.
ATOC is now continuing transmissions despite the fact that its Advisory Board noted that they "...could not categorically rule out a relationship between the ATOC transmissions and the [three humpback] whale deaths." The Advisory Board, however, concluded that the ATOC transmissions were "unlikely" to be responsible. No autopsies could be conducted on the three humpbacks.
It is disturbing to me that in a letter by Christopher Clark, director of the Marine Mammal Research Program for ATOC, to Ann Terbush, National Marine Fisheries Service, dated 9 Nov.,
"AFTER all three humpbacks were found in the general vicinity of the ATOC source, andLuckily, thanks in part to pressure from environmental groups, this did not happen. Nevertheless, as an initial reaction by Dr. Clark, this does not reflect a great deal of precaution and prudence from someone charged with determining whether the ATOC transmissions are harmful to marine mammals.
Lindy WeilgartSAN FRANCISCO, Jan 17 (Reuter) - After several weeks of testing a controversial experiment to measure global warming by transmitting noises deep in the ocean, scientists said on Wednesday they have so far found no change in animal behaviour.
Under a plan proposed by scientists at the University of California at San Diego's Scripps Institution of Oceanography, the low-frequency sounds would be picked up by receivers located around the Pacific Ocean, enabling them to detect long-term changes in ocean temperatures since sound travels faster in warmer water.
After environmentalists voiced concern about the possible effect of the noise on whales, dolphins and other marine mammals, project scientists agreed to a preliminary study by independent marine biologists to test whether the signals would have any adverse impact on the animals. The researchers installed a loudspeaker deep in the Pacific Ocean off the central California coast and began the preliminary study in early December, occasionally broadcasting the low-pitched rumbles at 185 and 195 decibels.
The marine biologists, headed by Dan Costa of the University of California at Santa Cruz, said on Wednesday that during the first five transmission cycles from the loudspeaker, they had observed no apparent changes in the behaviour of marine mammals in the area. But they said in a statement that more data would have to be collected and detailed analysis done before they could draw any definitive conclusions.
During each transmission cycle, which lasted from one to four days, the sound source was turned on for 20 minutes every four hours, the scientists said. The scientists said they had spotted large numbers of whales, dolphins and other animals near the loudspeaker both when the loudspeaker was on and when it was silent.
Initial data from 14 elephant seals, each carrying a satellite tag that tracks their position in the ocean, showed no dramatic changes in their migration route from Alaska to California waters, the scientists said. Some environmentalists had expressed concern that the noises could affect animals' migration patterns.
The loudspeaker is located 50 miles (80 kms) offshore from Half Moon Bay and 3,200 ft (1,000 metres) under the ocean surface.
The first phase of the experiment to test the impact on marine mammals will run at least through September 1996 when a decision will be taken on whether to go ahead with the global warming experiment, during which the loudspeaker will broadcast more regularly.
SANTA CRUZ, California (CNN) December 1, 1996
Several years ago, a low-frequency transmitter was proposed as one way to study ocean's temperatures and monitor global warming. Environmentalists objected, fearing the noise reverberating through the deep would disrupt whale and seal migration or cause deaths in the population.
The project went ahead, and scientists monitored the ocean life off the coast of California. Now, halfway through the two-year test, preliminary results are available, and it appears that the transmitter has had no ill effect.
"The animals are not abandoning the study site," said Dan Costa, a marine biologist at the University of California at Santa Cruz. "We're finding whales and lots of dolphins and lots of seals. The abundance has not changed ... So there's no dramatic effect."
Researchers outfitted some elephant seals with devices to measure changes in their swimming patterns.
"We can look at the animals' behavior changes in terms of how deep it dives, how fast it swims, "how much time it spends at the surface," Costa said. "With 14 animals, there were no changes of behavior."
Scientists took to the skies to see whether the animals would continue swimming near the site. But researchers admit it's tough to measure the finer details of behavior that far out at sea.
The big question is still whether the noise masks the sounds that marine mammals make to one another to communicate about feeding areas or the presence of a predator nearby. But the sounds of most marine mammals are of a much higher frequency than those of the transmitter.
"We don't think they'll be masking sounds they make," Costa said. "As far as other sounds that might be important to them, we just don't know."
Hearings will be held following the completion of the study next year. If scientists do not detect any negative effects on marine mammal behavior, the transmitters in California and Hawaii will begin sounding off on a regular basis.
Other references: The Great Whale Foundation