After watching the striking documentary The Cove about the dolphin massacres in Japan, I wanted to learn more about these smart, sensitive creatures of the deep. The “Olympics of Science” being held here in San Diego with thousands of international scientists featured two sessions on dolphins, so I zipped around to both.
Fascinating, although the news didn’t look great for them.
First, some interesting tidbits on dolphins: Diana Reiss, a psychology professor at Hunter College, explained that dolphins are self-aware, social and highly intelligent. “The cognitive cousins of the great apes who can learn sign language,” Reiss said.
Their brain is larger than ours, actually.
Lori Marino, a behavioral biologist from Emory University, said dolphin brains place second to people when you adjust for body weight. Marino argued it was unethical to keep dolphins in captivity at all. Representatives from the aquariums politely disagreed.
The thing is, there are plenty of issues in the wild too: Bottlenose dolphins are overloaded with PCBs off the Georgia coast. They’re getting papillomavirus, a sanitized name for genital warts, and some 50 other viruses. And in California, dolphins, sea lions and whales are coming down with epilepsy.
That one really struck me because the animals are seizing up and stranding along the California coastline, from Monterey to San Diego. At least five ailing dolphins were found in Coronado and Imperial Beaches in 2007.
The research started about 10 years ago when researchers at the National Oceanic and Atmospheric Administration started noticing marine mammals with a neurological disease similar to epilepsy.
NOAA toxicologist John Ramsdell said hundreds of animals, from whales to sea birds, were dying outright or exhibiting strange behavior. Sea lions, for instance, were spotted sleeping in public restrooms and climbing on police cars. Another visited a car dealership.
I had to make sure I heard Ramsdell right on that one. Yep, he assured me, sea lions use tributaries like streams to swim inland and then traverse land by flipper from there.
The reason they’re straying so far is a toxic algae that is every bit as inhospitable as it sounds. Pseudo-nitzchia lives naturally in the ocean but the algae produce “domoic acid” when stressed by pollutants like fertilizer and sewage.
“It is well known in humans that domoic acid poisoning can damage short term memory that can become permanent,” said John Ramsdell with the National Oceanic and Atmospheric Administration. “The type of memory that’s affected is what’s called visual special memory, which is ‘Did I leave my keys on the table or where is my car in the parking lot?’ It’s possible that animals have some difficulty finding something they normally could find.”
Like the coastline.
Ramsdell presented new research at the AAAS conference that showed lab rats got seizures and passed out when fed domoic acid.
That wasn’t so surprising to the researchers. But months later, almost all the rats went on to develop full-blown epilepsy. This is new, and could have relevance for people.
While it’s known that eating contaminated shellfish can lead to chills, fever, even convulsions, it’s not clear if domoic acid poisoning can cause chronic epilepsy in humans.
Ramsdell told me at least one person, an 84-year old Canadian man, developed temporal lobe epilepsy a year after eating contaminated mussels.
He also emphasized that U.S. waters are well monitored for domoic acid in the quantities that would harm people.
“It would take a very unusual circumstance to have enough domoic acid in shellfish to poison people so severely as we find in dolphins, whales and sea lions,” Ramsdell said.
Several researchers seemed to agree. Either way, they’re a sentinel species. Dolphins forewarn us of threats, and offer the promise of new discoveries for human health, maybe even cures.
A philosopher at the conference went so far as to call dolphins “non-human persons.” Thomas White from Loyola Marymount University felt dolphins fit the personhood checklist: they have emotions, personalities and ethics.
— REBECCA TOLIN