It’s been more than a week now, and it looks official. A dolphin has declared squatter’s rights in the Bolsa Chica Wetlands.
The 7-foot adult male was first spotted circling the shallow wetlands April 26. The creature was originally thought to be trapped, and rescue crews worked to usher him out into the open waters of Huntington Harbor. And out he swam … for about 30 seconds, until two aggressive dolphins that had been circling in the harbor for days charged him, sending him retreating to the shallows in a hurry, said Peter Wallerstein, a 27-year veteran of marine mammal rescues.
Rather than force a potentially dangerous confrontation, the volunteers decided to monitor the situation. As long as the mammal seems healthy and content to dwell in the wetlands, the rescue workers won’t evict him.
“We’re taking it day-by-day, but for now there is no need to do anything,” Wallerstein said. “The dolphin is in good shape. There is plenty of food, and he has been observed eating.”
He’s been observed a lot in the last week, as the unofficial Bolsa Chica mascot has become a local celebrity, drawing crowds to bridges overlooking the water and spurring groups to walk the wetlands trails in hopes of spotting him.
Because it’s rare to see an adult dolphin vacationing in the wetlands for an extended stay, there was concern it could be suffering from domoic acid poisoning. Domoic acid is a naturally occurring biotoxin found in algae blooms off the California coast. When domoic acid is present, sick, dying and disoriented sea lions and dolphins will often beach themselves.
However, this dolphin shows no signs of a neurotoxin poisoning, Wallerstein said.
“I have been doing this for 27 years, and I don’t see anything that says to me it has been contaminated with domoic acid.”
A dolphin that beaches itself because of domoic acid typically dies quickly, Wallerstein said. They may have seizures and other obvious signs of illness.
“With this animal, I don’t see anything so severe –- not even one red flag that would make me think it is a neurotoxin,” Wallerstein said.
There is little reason to suspect the animal has been exposed to domoic acid, said David Caron, a microbiologist, who studies the toxin.
“We have no other signs of a toxic bloom going on at this time,” Caron said.
Locally, toxic blooms usually appear between February and June, and when they are in effect, there are usually several animals that exhibit sypmptons, added Caron.
Volunteers will continue to observe the dolphin, monitoring its heart rate and overall health.
“As long as he is doing OK, we’ll wait,” Wallerstein said.
But the poisoning isn't "on" or "off" -- it can be survived. Humans got it in maritime Canada in the 80s, and many survived with temporal lobe epilepsy and memory issues, without grand mal seizures but with what's called absence seizures, just spacing out and disorientation and confusion. It's possible that the dolphin has a sublethal poisoning, but there's no way to know without an autopsy, and even then it's dicey. Only this year -- in fact only this past month, NOAA's announced an *experimental* blood test for chronic exposure to domoic acid, which may produce a more chronic form of Amnesiac Shellfish Poisoning in birds and mammals (including humans -- we really have no idea how many cases may go unreaported because we don't educate doctors on the signs).