Tuesday 14 August 2007
Scientists checking if testing, drilling off Alaska would disturb habitat.
Anchorage, Alaska - Scientists are searching this summer for one of the most precariously positioned animals on the planet - Pacific right whales.
The whales, once prized by commercial whalers, have been teetering on extinction for decades. The search for the slow-moving behemoths is being prompted by the search for a less rare but increasingly valuable commodity - oil and gas in the Bering Sea.
The problem is that the area where the whales have shown up in surprising numbers in recent years overlaps an area the federal government earlier this year approved for oil and gas development. Lease sales in the southeastern Bering Sea are proposed for 2011.
It is an unfortunate juxtaposition, said Brendan Cummings, oceans program director for the Center for Biological Diversity, which is fighting the federal government's five-year oil and gas development plan for the Bering Sea. He said that it is no surprise that the U.S. Minerals Management Service is funding the whale survey.
"Their existence is so tenuous as it is," Cummings said. "Any new research is completely welcomed. The unfortunate irony of it is that the impetus to do this research is propelled in part by the Department of the Interior proposal to open up right whale critical habitat to oil and gas leasing."
Last year, the center was successful in getting the National Marine Fisheries Service to designate almost 36,000 square miles of the Bering Sea as critical habitat for the whales. Some of that designated habitat is within the North Aleutian Basin, an area that the Bush administration has proposed to open up for oil and gas leasing.
This summer's survey is part of a larger four-year project to assess the seasonal distribution of the whales, their numbers and where they go.
With oil and gas development looming, the more detailed information is required under the Endangered Species Act. Right whales have been listed as endangered since the early 1970s.
It's believed that perhaps 11,000 of the slow-moving whales once swam the Northern Pacific. Current estimates put the number at less than 100, perhaps fewer than 50.
National Oceanic and Atmospheric Administration scientists are being joined by colleagues from Russia, the Dominican Republic, Brazil and South Africa in the survey, which will cover about 42,471 square miles in the Bering Sea.
The ESA requires that an assessment be made of how oil and gas development could affect the few whales left. That means finding out how many whales there are and where they go, said Alex Zerbini, a whale biologist with the National Marine Mammal Laboratory in Seattle.
"We don't know whether these whales actually move to the lease area. If they don't, the impacts could potentially be smaller than if they move into the lease area," he said.
Optimism From 2004 Survey
The last survey in 2004 found a surprising number of whales at the summer feeding grounds, including two calves. Evidence that the whales were reproducing has raised hopes that perhaps they will not go extinct after all.
On July 31, nine researchers departed Dutch Harbor aboard the NOAA vessel Oscar Dyson and headed to the summer feeding grounds about 200 miles away. The scientists spent two weeks on the research vessel followed by another two weeks on a chartered fishing vessel.
To aid in finding the whales, scientists are carrying "big eye binoculars" - high-powered binoculars capable of seeing seven miles. They also will have underwater microphones, called hydrophones, that can pick up whale sounds up to 50 miles away.
Zerbini said the most important question is where do the whales go? Scientists don't even know where the whales spend the winter, he said.
"Do they occupy a relatively small habitat in the feeding grounds or do they move around a lot? Where do they go for breeding and calving?" he said.
Zerbini said the Oscar Dyson comes with quieting technology, allowing scientists to track marine mammals and fish without disturbing them.
Cummings said it's odd that the government would care about the noise created when searching for the whales but apparently unconcerned about noise that will be created by oil and gas exploration.
"Perhaps the worst thing we can do for the right whales is oil and gas development in their area," he said. "A lease does not simply mean a single oil rig is magically installed. It is seismic surveys that can disturb and potentially even kill the whales."
Satellite Tags Planned
Scientists plan to place satellite radio tags on up to five whales. They also will be taking photographs to identify individual whales and small biopsy samples to add to an existing database. The samples will be used for genetic analysis, as well as determining what the whales like to eat and any contaminants they may be exposed to.
"We know very little about this population," Zerbini said.
Hydrophones moored to the ocean floor indicate that the plankton-eating whales probably are in the area from May through October. The largest amount of whale calls occurs in September.
Scientists report that soon after leaving Dutch Harbor in late July they spotted humpback whales and harbor porpoises. On Aug. 2, the ship's acoustics picked up calls from fin whales. Killer whales also have occasionally been seen near shore.
Right whales, so far, are proving more elusive. No sightings the first week.
"They're huge - but finding even something that size in the vastness of the ocean is a major challenge," said project leader Phil Clapham of the National Marine Mammal Laboratory, in an e-mail from the ship. "However, we urgently need to better understand the status and habitats of these whales in order to better aid their recovery."
A rotating team of three observers who stand watch on the ship's top level bridge are keeping a lookout between 8 a.m. until past 10 p.m. A two-person acoustics team is listening mostly at night when right whales are likely to be more vocal.
The whales, which can grow to more than 60 feet long and 100 tons, have been protected since 1935. But in the 1960s an illegal event occurred that many scientists believed was the final blow. The Soviet Union harvested 372 right whales in the Gulf of Alaska and the Bering Sea.
Zerbini said it's too early to know if right whales will survive.
"It is encouraging that we are seeing more whales, and are seeing males and females and seeing calves," he said.
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