Seismic testing shakes up environment

The BATHOLITHS project, a U.S.-led seismic survey initiative, poses a threat to British Columbia's salmon and marine mammals. Pending approvals, the project is set to begin seismic testing in marine and terrestrial environments on B.C.'s central and north coast in 2007.

The BATHOLITHS project would use some of the world's loudest air gun arrays to determine how the Coast Mountains were formed. These seismic surveys have the potential to deafen whales and dolphins that happen to be in the vicinity during the survey as the sound can ricochet off the sides of the inlets and carry up the channels.

Seismic testing in the marine environment uses air guns to fire compressed air at the ocean floor. This high-energy explosion sends shock waves through the water and the rock layers beneath the ocean floor. These are then reflected from different layers, at various intervals, back through the rock and water, and are recorded by hydrophones and seismographs. These recordings are then mapped, providing a picture of the geology being studied.

The method being used by the BATHOLITHS project for seismic testing in the terrestrial environment involves detonating explosives on land. Blasting along the Bella Coola River valley (to be measured by acoustic arrays in the ocean) while salmon are spawning and eggs are incubating also poses a threat to egg survival.

Before the BATHOLITHS project can proceed, it must receive approval from Canada's Natural Sciences and Engineering Research Council, which is contributing $263,898 to the project. The U.S.-based National Science Foundation is contributing $4.5 million.

It is believed that seismic testing may hinder whale-to-whale communication and threaten the species' ability to navigate, kill prey and reproduce. Dr. David Bain, a marine mammal scientist at the University of Washington, says whales and dolphins in B.C. could be driven aground by the kind of seismic testing the BATHOLITHS project is proposing. Bain also states that if a whale or dolphin beaches itself, it probably will die.

The International Whaling Commission has unanimously endorsed a report by its scientific committee that expresses increased concern about the effects of seismic surveys on whale populations. Having dropped out of the IWC in 1990, Canada has been absent from a highly relevant scientific discussion for 16 years. As a result, Canada's seismic policy will not be subject to this international peer review process.

Surveys to estimate abundance of most of B.C.'s cetaceans (whales, dolphins and porpoises) have never been conducted by provincial or federal governments in Canada. In the U.S., such data for marine mammals are collected as a matter of course. The prospect of seismic testing in B.C.'s coastal waters has lent urgency to Raincoast Conservation Society's decision to gather data on acoustically sensitive marine mammals.

For the past three years, Raincoast has been conducting systematic line-transect surveys to measure abundance and distribution of marine mammals on the B.C. coast, which will provide basic inventories critical to the debate regarding seismic testing and related offshore oil and gas exploration.

The bottom line, however, is that whales and dolphins won't make a distinction between being deafened by seismic testing for oil and gas exploration or invasive academic research such as the BATHOLITHS project. Both kinds of seismic surveys pose a threat to marine mammals and fish on the B.C. coast.

Chris Genovali is the executive director of Raincoast Conservation Society.

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