Revealing the Cove Dolphins' Toxic Secrets
With the dolphin-killing season in Taiji, Japan, nearing its expected March 1 end, meat from striped dolphins slain last month in the notorious cove has tested positive for high levels of mercury and for trace but legally safe levels of radiation, said Ric O'Barry of the Dolphin Project on Tuesday.
O'Barry, star of 2009's Oscar-winning documentary The Cove, which put a global spotlight on the town's annual hunt, purchased the meat in January from a Taiji supermarket and sent it to a Tokyo laboratory for testing.
Even without a smoking gun radiation test—which activists would have wielded to pressure the Japanese government to end the hunt—the mercury results, coupled with comparable findings in years past, will be used to educate the Japanese people on the dangers of eating mercury-rich dolphin sashimi.
O'Barry said growing awareness of contaminated dolphin meat has led to a decline in its consumption.
"The more time I spend on the ground in Taiji, talking with local police and concerned citizens, the only thing, really, I find that's going to stop the hunt is if people realize they're eating poison," O'Barry said. "We must double down on this mercury angle—it's the weak link, the Achilles' heel, in the Taiji pipeline."
The meat O'Barry tested was found to contain 1.4 parts per million of mercury. The Japanese government's advisory level for the element is 0.4 ppm.
Tests in previous years have yielded similar results.
From 2002 to 2006, Tetsuya Endo, one of the world's leading experts on mercury levels in marine mammals, bought more than 50 samples of dolphin meat at Taiji markets. Tests conducted on the meat found "the average levels of mercury and methyl mercury in pilot whale meat were 9.6 ppm and 5.9 ppm," Endo told The Japan Times. The government limit for methyl mercury, the most toxic form of the heavy metal, is 0.3 ppm.
In 2012, dolphin meat purchased in and around Taiji by environmentalists from the Elsa Nature Conservancy, a Japanese nonprofit, was found to contain three-and-a-half times the country's maximum allowed level for mercury.
Both dolphin and whale meat contain high levels of the element because mercury is emitted into the atmosphere by coal-burning power plants and other industrial facilities. That mercury is carried into the ocean, where it is absorbed by marine organisms and, over time, is passed up the food chain to dolphins and whales.
Fetuses and young children are especially vulnerable to mercury, which affects the development of the nervous system.
Humans aren't the only sentient mammals affected by mercury; it harms the dolphins too.
Mercury and other toxins "have been linked to increased rates of cancer, increased first calf mortality, immune suppression, and a higher susceptibility to infectious diseases, [and] are postulated to be a primary factor causing population declines," according to Toxic Catch, a 2013 comprehensive study on Taiji dolphin meat conducted by the London-based Environmental Investigative Agency.
"It's a terrible, terrible thing for dolphins," said Luca Giovagnoli, the resident marine mammal veterinarian at the Dolphin Project. "It particularly impairs their neurological function, just as it does for humans."
Environmentalists have been concerned about the possible presence of radiation in dolphin and whale meat since March 2011, when the Fukushima Daiichi nuclear power plant disaster released large quantities of irradiated elements into the ocean.
But the meat O'Barry tested was found to contain just three Becquerels per kilogram of radiation. The Japanese government considers anything higher than 100 Becquerels per kilogram to be unsafe. By comparison, three months after the Fukushima meltdown, two of 17 minke whales caught and killed off the coast of Hokkaido were found to contain 31 and 24 Becquerels per kilogram, respectively.
"If Dolphin Project—or anyone else—finds radiation levels in Taiji dolphin meat higher than 100 Becquerels per kilogram, it would be big news that would shut down the supply and demand of the industry," O'Barry said.
As the 2014–15 hunting season concludes on or near March 1—Taiji fishers will stop hunting dolphins the day after they see bonito, their next target, swimming under their boats—the number of dolphins slaughtered or captured for sale to aquariums is down from last season.
From Sept. 1, 2014, the start of the hunting season, through Feb. 8, 2015, there have been 654 dolphins slaughtered in the cove, according to data compiled by the website Ceta-Base, from estimates given by Cove Guardians, the on-the-ground volunteers for the Sea Shepherd Conservation Society, volunteers for O'Barry's Dolphin Project, and the Japanese Fisheries Ministry. Last season, 831 dolphins were killed. The number of dolphins captured for sale in January 2015 is roughly half what it was in January 2014.
O'Barry cautioned there is still plenty of time before the season's end for the hunters to kill "far too many more dolphins" in a last-ditch attempt to reach their 1,938-specimen quota.
"If we continue testing for contaminates and publish the results wherever possible, it will have an impact on the consumers—it just will," he said.
In January 2007, O'Barry and journalist Boyd Harnell tested meat from a dolphin killed in Taiji that they purchased at the Okuwa Supermarket in Shingu, about a 45-minute drive from the cove.
It was found to contain high levels of mercury, so they confronted the store manager with the results. “A few weeks later the giant supermarket chain announced that they would remove all dolphin meat from all of their 137 supermarkets," O'Barry said. "It works, and we will do it again."