The US Congress is considering proposals that will make it easier to get permission to use high-volume sonars in the ocean - just as fresh evidence suggests that their noise can harm marine mammals.
Capitol Hill is looking at two measures to loosen the 1972 Marine Mammal Protection Act (MMPA), which sets guidelines for noisy experiments in the oceans. One would simplify the rules, making it easier to get permission to do the experiments. The second would exempt the US Navy from the regulations on the grounds of national security.
The changes are supported by the navy and by some geophysicists, who want to use noise-generating devices to study geological formations on the ocean floor. But they are strongly opposed by many marine biologists. "There is a huge split over the issue," says John Hildebrand, who studies marine mammal acoustics at the Scripps Institution of Oceanography in La Jolla, California.
In a Brief Communication in this issue of Nature, a team led by Paul Jepson of the Institute of Zoology in London concludes that 14 whale deaths off the Canary Islands last year may have been caused by decompression sickness after the animals shot to the surface to escape sonars during Spanish-led international naval exercises1. The team says the sonar appears to have caused gas bubbles to form in the blood, damaging the whales' livers and kidneys.
Experts say that the study provides some of the most direct evidence to date that sonars can kill marine mammals. "This report has the potential to be the 'smoking gun' on the cause of sonar-related mammal strandings," says Hildebrand. "It certainly focuses on the potential dangers of sonar, which need to be thoroughly investigated."
On 25 September, however, the oceans subcommittee of the House of Representatives Committee on Resources passed a 'reauthorization' of the MMPA that would give government agencies more freedom to permit experiments in the oceans. Agencies could also ask for stronger proof that a study might cause damage. The bill will soon be considered by the full committee, where some Democrats will seek to tighten its provisions.
Meanwhile, a House-Senate conference committee is due to consider a 2004 military spending authorization bill that would exempt the navy from the sonar rules. "We fear something bad" is going to come out of the conference, says Karen Wayland, a geologist with the National Resources Defense Council, an environmental group that took successful court action to block the navy's use of some sonar devices2.
This report has the potential to be the 'smoking gun'.
John Orcutt, a geophysicist and deputy director of Scripps, says that he favours the proposed modifications to the MMPA, so that researchers can secure permits more easily than at present. "The process is tremendously flawed," he says. Orcutt is worried, however, that the navy exemption would encourage the military to do all of its own experiments and stop supporting external researchers, who would remain constrained by the law.
But marine biologist Ken Balcomb, director of the Center for Whale Research in Friday Harbor, Washington, says recent deaths and strandings of marine mammals should persuade physical oceanographers - and Congress - to worry more about protecting these animals instead of loosening research regulations.
1) Jepson, P. D. et al. Was sonar responsible for a spate of whale deaths after an Atlantic military exercise? Nature, 425, 575 - 576, doi:10.1038/425575a (2003). |
2) Dalton, R. Court ruling sounds note of caution for sonar system Nature, 425, 6, doi:10.1038/425006a (2003).
Nature 425, 575 - 576 (09 October 2003); doi:10.1038/425575a
Gas-bubble lesions in stranded cetaceans
P. D. JEPSON*, M. ARBELO†, R. DEAVILLE*, I. A. P. PATTERSON‡, P. CASTRO†, J. R. BAKER§, E. DEGOLLADA†, H. M. ROSS‡, P. HERRÁEZ†, A. M. POCKNELL*, F. RODRÍGUEZ†, F. E. HOWIE, A. ESPINOSA†, R. J. REID‡, J. R. JABER†, V. MARTIN†, A. A. CUNNINGHAM* & A. FERNÁNDEZ*
* Institute of Zoology, Zoological Society of London, Regent's Park, London NW1 4RY, UK
† Histology and Pathology Unit, Institute for Animal Health, Veterinary School, Montana Cardones-Arucas, University of Las Palmas de Gran Canaria, Gran Canaria, Spain
‡ Wildlife Unit, SAC Veterinary Science Division (Inverness), Drummondhill, Stratherrick Road, Inverness, IV2 4JZ, UK
§ Department of Veterinary Pathology, University of Liverpool, Leahurst, Neston, Wirral CH64 7TE, UK
SAC Veterinary Science Division (Edinburgh), Allan Watt Building, Bush Estate, Penicuik, Edinburgh EH26 0QE, UK
There are spatial and temporal links between some mass strandings of cetaceans — predominantly beaked whales — and the deployment of military sonar. Here we present evidence of acute and chronic tissue damage in stranded cetaceans that results from the formation in vivo of gas bubbles, challenging the view that these mammals do not suffer decompression sickness. The incidence of such cases during a naval sonar exercise indicates that acoustic factors could be important in the aetiology of bubble-related disease and may call for further environmental regulation of such activity.
Ref = 2)
Nature 425, 6
4th September 2003
Court ruling sounds note of caution for sonar system
A court has ordered the US Navy to come up with an environmental plan before it extends the deployment of a submarine-detection system that some biologists say could disturb and harm marine mammals and fish.
The ruling by a federal judge in San Francisco could end a prolonged wrangle between the navy and environmentalists over the use of the sonar system (see Nature 413, 242; 2001).
Environmental groups and the navy will meet on 7 October to work out terms for deploying the new sonar, which emits a low-frequency, 140-decibel sound wave that is able to pick up echoes from submarines hundreds of kilometres away.
On 26 August, Judge Elizabeth Laporte of the US District Court in San Francisco ruled that the navy did not have proper environmental permits to test and use the sonar system widely. Environmentalists greeted the ruling as a major victory in their long-running efforts to block its deployment. The navy, even as it complies with the ruling, will push Congress to change the law.
In her 73-page ruling, Laporte said that the case required a difficult balancing act between national security requirements and laws enacted to protect sea life. She declined to ban the sonar outright, but sought a permanent, court-approved plan to allow broader use of the equipment while protecting sea life.
The decision "recognizes that during peacetime even the military must comply with our environmental laws", says Joel Reynolds, a senior attorney for the Washington-based National Resources Defense Council, the environmental group that led the lawsuit. The navy said that it was "concerned about the implications of the decision for national defence".
Currently, the navy can only test and train with the new sonar system in a region covering two million square kilometres near Guam in the western Pacific Ocean. But the navy wants to use it in ocean habitats that are populated by whales and other species that are already suffering environmental pressures.
Other sonars that operate at higher frequencies have been linked to incidents in which whales, dolphins or porpoises were harmed or killed (see Nature 415, 106; 2002).