Scientists Worry Seismic Testing Could Harm Whales

BY JOHN M. BIERS - c.2002 Newhouse News Service

In the 18th century, sperm whales in America were hunted for spermaceti, a liquid in the whale head used to make candles. In the 19th century, whalers gutted the rest of the animal for sperm oil, which made a dandy illuminant. In the first part of the 20th century, whale parts were used in a variety of consumer products, such as colored pencils.

As an endangered species in the United States since 1970, sperm whales now enjoy protection from this sort of exploitation. But with the advance of energy companies deeper into the Gulf of Mexico, the giant creatures once again find themselves in potentially hostile waters.

The worry is that the booming noise from oil and gas seismic testing may hinder whale-to-whale communication and threaten the species' ability to navigate, kill prey and reproduce.

To determine if and how seismic testing harms the animals, researchers this summer tagged 38 whales as part of a three-year study of the Gulf's sperm whales, estimated to number 530.

In the meantime, as a precaution, government officials have unveiled new regulations to protect the whales from seismic tests, which use repeated underwater sound blasts to map potential oil and gas reserves deep within the Earth.

While environmentalists and other whale advocates have applauded tough oversight of offshore operations, the new rules have raised the ire of the seismic industry, which successfully lobbied the federal Minerals Management Service this summer to drop some of the most onerous requirements.

The controversy in the Gulf is the latest to place whales at the nexus of the evolving global debate over how to balance modern innovations with environmental protection.

Spanish scientists last week said 15 beaked whales beached on the Canary Islands probably were stranded after fleeing sonar testing. Autopsies found brain damage consistent with impacts from military sonar signals.

Environmentalists in Russia in summer 2001 were unable to persuade ExxonMobil to postpone offshore seismic testing near Sakhalin Island until Western Pacific gray whales in the area had a chance to migrate to the South China Sea for the winter. Scientists had postulated the whales, which number fewer than 100 globally, were fleeing offshore operations in their prime feeding area, according to a story in The Wall Street Journal. After the drilling started, the whales grew unusually thin.

The effort in the United States comes as officials in the United Kingdom grapple with proposals to protect whales, seals and other marine mammals from noise associated with seismic testing. Australia and Brazil have regulations to protect mammals offshore that are considered more restrictive than the current U.S. proposal, said Kyle Baker, a fishery biologist with the National Marine Fisheries Service.

Oil and gas companies and sperm whales in the Gulf of Mexico have coexisted for decades. But until recently, most offshore operations took place in water depths shallower than the 700 to 900-meter range the animals frequented.

But as the energy business in the past 15 years has moved outward in search of large underground reserves in deep water, so have the booming seismic tests.

Under a typical test, a seismic vessel simultaneously shoots off 15 to 20 airguns aligned in an array, sending soundwaves that rush through the water to the sea floor and register deep within the Earth. High-tech streamers pulled by the vessel record the waves as they reflect upward. The data are then transferred to a computer, which provides a three-dimensional view of the geology beneath the sea floor.

Sperm whales are thought to rely on a similar noise-related process for killing their prey. Whales on the hunt will make a clicking noise and detect the presence of food by how the noise reflects.

Of all whale species, none has inspired the human imagination more than the sperm. The famed creature of Herman Melville's "Moby Dick," the sperm whale grew to mythical proportions as 19th century Nantucket whalers braved the world's oceans in wooden ships to hunt the legendary cetacean for its precious oils. The whales can measure 60 feet long and weigh 70 tons.

Known for its sometimes aggressive behavior and deep dives, often staying under water for more than an hour, the toothed mammal devours giant squid and even sharks while its tamer baleen cousins munch plankton and shrimp. Evidence suggests the whale's disproportionately large head is an adaptation to allow it to produce loud low-frequency clicks.

Two million sperm whales may have existed at one time. Researchers say population estimates are difficult because the animals spend so much time diving, but the animals are thought to number at least into the tens of thousands.

Scientists have only a sketchy idea of how sperm whales live, but many believe the animals make the clicking sounds to communicate with each other.

"You can hear two whales exchanging `codas' like they're talking back and forth on the telephone," said Bill Long, a program coordinator for a sperm whale study by the Minerals Management Service.

Regulators believe these low-frequency clicks are crucial to the whales' social interaction and prospects for reproducing. That means sperm whales in close proximity to seismic surveys "are likely to be harassed by the frequency and intensity levels associated with these activities," according to a recent Fisheries Service study of how oil exploration in new regions of the Gulf will affect sperm whales.

Because the whales have a low rate of reproduction, "even small negative impacts of noise ... could cause population declines," the report said.

Baker, the fisheries service biologist, said sperm whales can hear frequencies as low as 100 hertz, a level that overlaps with emissions from seismic blasts. Seismic explosions typically peak at about 260 decibels. Humans begin to feel discomfort at 120 decibels while marine mammals feel discomfort at 180 decibels.

"The evidence is mixed, but there's scientific evidence to suggest they are hearing it and responding," Baker said.

The Minerals Management Service, the federal agency that regulates oil and gas exploration and production in U.S. federal waters, began circulating drafts of rules in August to protect the whales.

The regulations directly impact only the geophysical industry, mostly service firms that specialize in seismic surveys. But the new costs of abiding by the rules likely would be passed on to other oil service companies as well as operators, such as ExxonMobil and Shell.

The rules included barring seismic tests if sperm whales are observed in the area, hiring government-approved staff to watch for whales and requiring seismic companies to perform a ramp-up, starting with one gun before undertaking a full test.

Whale advocates, such as Michael Dyer, librarian for the New Bedford Whaling Museum in Massachusetts, applaud the new rules.

"We have all this great technology and we can use it to get oil and gas. But we don't know what it does to the stuff in between," he said. "For all we know, there could be grave environmental results from proceeding with a technology that we don't completely understand."

But the proposal drew swift protest from the International Association of Geophysical Contractors, which represents 140 companies, and its president, Chip Gill.

At a five-hour meeting with Minerals Management Service Director Chris Oynes in Houston, Gill persuaded the agency to make a number of changes. The biggest involved decreasing the size of the exclusion zone, the area that must be whale-proofed prior to testing.

The original proposal required a computation to determine the size of the zone, which Gill said could theoretically create a five-mile exclusionary zone. Such a massive zone would have barred nighttime testing and required seismic companies to use fixed-wing aircraft or chase boats to look for whales. The agency ultimately decided to enforce a 500-meter radius zone, the same area used to protect mammals in the North Sea.

To environmentalist Richard Charter, the changes suggested the government caved in response to industry pressure.

"It appears that the oil industry was able to exert inappropriate political influence to undermine the recommendations of federal scientists and agency managers about how best to protect sperm whales in the Gulf from the adverse impacts of seismic surveys," said Charter, a marine conservation advocate for Environmental Defense in California. "We're in the era of management of our biological systems by political cronyism."

Oynes was unavailable for comment.

(John Biers is energy writer for The Times-Picayune of New Orleans. He can be contacted at

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