Conundrum

At the same time hundreds of dead gray whales were washing up on beaches, their birthrate was plunging. Theories abound, but little hard data has been gathered to solve this environmental puzzle.

The latest report continues to put the total number of Eastern Pacific gray whales at more than 26,000, an ecological success story considering that in the 1930s the population had dropped to fewer than 8,000, and the whales were put on the U.S. Endangered Species list in 1970.

In 1937, the gray whales were protected from commercial hunting by international agreement, a ban that was formalized in 1946 with the advent of the International Whaling Commission. U.S. monitoring of gray whales has been going on since the 1950s.

By 1994, the Eastern Pacific gray whales had rebounded significantly and were removed from the list. (The Western Pacific gray whale continues to be listed as a "critically endangered" species.)

David Janiger of the Natural History Museum of Los Angeles County 
prepares to examine a beached gray whale.
Alisa Schulman-Janiger/Natural History Museum of L
David Janiger of the Natural History Museum of Los Angeles County prepares to examine a beached gray whale.
David Janiger of the Natural History Museum of Los Angeles County 
prepares to examine a beached gray whale.
Alisa Schulman-Janiger/Natural History Museum of L
David Janiger of the Natural History Museum of Los Angeles County prepares to examine a beached gray whale.

Details

The recovery of the Eastern Pacific gray whale from the brink of extinction is the single greatest turnaround of a marine mammal population, and the whale's myriad connections to human cultural conflicts are no less impressive in their scope.

In New Times' special project "Shades of Gray," reporters from several of our papers have traveled from Siberia to Mexico to tell the complex tale of a creature whose annual migration -- at 12,000 miles round trip -- is the longest by any mammal. The trek joins the competing interests of Indians, scientists, environmentalists, and local residents. In this issue, Patti Epler explores the science, the money, and the politics behind gray whale research. With hundreds of whales mysteriously washing up dead and a plunging calf count coupled with reports of chemical contamination, scientific research has taken on a new urgency.

Visit Shades of Gray
A series documenting the perils, cultural conflicts and global and ecological warnings surrounding the gray whale.

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Earlier this year, volunteers who staff a whale-watching station in Southern California reported that the 2001 migration had been a healthy one.

"I saw some of the biggest, fattest whales I'd seen in quite awhile this year," says Alisa Schulman-Janiger, a high school marine biology teacher from San Pedro, Calif., who oversees the volunteer count as head of the Los Angeles chapter of the American Cetacean Society.

From December through May, volunteers peer out to sea from atop a 125-foot-high cliff near Point Vicente, just south of L.A. They use binoculars and spotting scopes to capture a view of passing marine mammals and other sea creatures. They rely on years of experience and training to be able to spot a hump in the water hundreds of yards out, and then figure out if it's male or female, young or old, fat or skinny.

The whales head north in two pulses, according to Schulman-Janiger. The first includes animals without calves, and about six weeks later, the watchers begin to document mothers with calves.

The volunteers had been dreading this season, anticipating a third year of starving whales.

Instead, Schulman-Janiger's final report calls the spring 2001 migration an "exotic season." Volunteers documented a large number of marine mammal species, including humpback, blue, minke, and killer whales, two very rare sei whales, sea lions, seals, sea otters, and numerous species of dolphins. One "megapod" contained more than 10,000 dolphins, she reported.

Schulman-Janiger doesn't think there will be a lot of strandings during the coming migration. She expects to see more calves and an overall healthy look to the whales that would suggest they're feeding well and perhaps expanding their feeding ranges to other areas. "I would predict the whales will continue to look fat and sassy," she says.

"Next year is going to be extremely telling."


Over the years, scientists have become comfortable with a gray whale population that appeared to be growing at the rate of about 2.5 percent per year, measured from the 1960s through the 1990s.

But several years ago, something went seriously awry. By the end of the 1999 migration, at least 263 gray whales had stranded, compared with 52 the year before and even fewer than that per year for many years prior.

The 2000 migration was even worse -- more than 350 gray whales turned up dead.

And those were just the ones that came ashore or were found floating in nearshore waters. No one knows how many grays perished and vanished in deeper waters.

One thing was clear, even as the first few dozen whales began to litter the beaches of Baja early in 1999 -- the whales were starving. Reports of emaciated whales began to flow in with what seemed like every new tide.

Some researchers began calling for serious efforts to determine why the whales appeared to be undernourished. Logically, they reasoned, that would mean looking at the whales' primary food supply -- the shrimplike amphipods that live in the mud on the bottom of the Bering and Chukchi seas, off the coasts of Alaska and Russia. The whales eat only in the summer, sucking in large amounts of muck and screening the amphipods through their baleen.

It's not hard to imagine the huge amount of tiny creatures these giant animals need to sustain them through a round-trip journey that takes about eight months and covers 12,000 miles. So, scientists postulated, starving whales in the spring of 1999 must mean they didn't eat very well in the summer of 1998.

Equally alarming, the birthrate of gray whale calves also has been abnormally low over the last few years. The number of calves counted by scientists during the spring -- when the small whales are still with their mothers on the journey north -- has dropped from about 1,400 in 1997 to about 250 in 2001.

In fact, calf production this year is the lowest recorded in eight years of monitoring, says Wayne Perryman, an NMFS biologist based in La Jolla, California, and the government's main specialist on calf birthrates.

That, too, is probably related to the food supply in the Bering Sea, he says. For the last few years, northern winters have been "very, very severe," Perryman says. Seasonal ice that covers the northern seas in winter has been slow to recede, and whales arrive to find their main feeding grounds still blocked or inaccessible. Perryman says the Bering and Chukchi seas have seen abnormally heavy seasonal ice in recent years.

That's made for a much shorter feeding time for gray whales. Pregnant whales "have to get fat in a short period of time," Perryman says. "Then they have to support the fetus, give birth, and then lactate and feed a calf. It's really a very big deal."

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