Safeguards on seismic testing technology for an oil and gas project in the Pacific have helped protect endangered whales from harm.
Seismic testing is carried out by specialised vessels that tow cables containing an airgun to create seismic blasts of 230 to 250 decibels and a series of hydrophones – microphones designed for underwater use – to map the reverberations and help detect deposits of oil and gas
Research has shown seismic testing, which can be so loud that it can sometimes be detected 2,500 miles away, can harm whales and other animals that rely on sound for their primary form of communication.
But conservationists working with Sakhalin Energy Investment in Russia from 2006 to 2012 said the tiny population of endangered Western Grey whales studied had risen about 3 per cent a year to 140, despite seismic testing near their feeding grounds.
The International Union for Conservation of Nature (IUCN), the world's biggest environmental alliance that includes governments, scientists and conservation organisations, said the safeguards put in place are a model for managing the deafening blasts.
"This work helps to set a standard," Carl Gustaf Lundin, director of the global marine and polar programme at the IUCN, told Reuters. "Once you have raised the bar ... other companies will look bad if they are not deploying it," he said.
The IUCN includes governments, scientists and conservation organisations and is the world's biggest environmental alliance.
He said there was no sign of "significant direct impact on the whales" from the testing off Sakhalin Island north of Japan. Sakhalin Energy groups Gazprom, Royal Dutch Shell, Mitsui and Mitsubishi.
A common and worrying effect of seismic testing was that the whales move away from their normal feeding grounds, Doug Nowacek of Duke University, lead author of the findings published in the journal Aquatic Mammals, told Reuters.
"The potential exists, if animals get too close (to testing areas), for trauma and injury," he said, adding that to his knowledge no such cases have been documented.
The IUCN said the guidelines called for thorough advance study of wildlife to help decide when it was best to carry out seismic tests, limiting noise levels, halting surveys if animals were seen in the area and follow-up monitoring.
"This is a comprehensive guidebook for how to do this with minimal impact," said Nowacek.
Off Sakhalin, for instance, understanding whale migrations meant it was best to do seismic testing in spring, after ice had melted but before many whales had returned to the region. Whale sightings also varied a lot from year to year.
"A clear message is that it is not enough to send out a few people for a week or two in a boat and then decide how many whales there are," said Greg Donovan, who chairs an IUCN group looking into the problem of the whales and seismic surveys.
More stringent guidelines would tend to push up costs of environmental monitoring, especially if it meant million-dollar delays to drilling. On the other hand, harming wildlife could damage companies' reputations.