Dolphin behavior intrigues watchers, puzzles experts

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John De Herrera stopped by a friend’s house at El Pescador beach Friday around 8:30 a.m., hoping to catch some early morning waves. Climbing atop a nearby rock to check on the surf, what caught his eye instead was an unusual sight a short distance away.

“I looked down and there was a [dolphin] carcass in the water and there were some dolphins around it,” De Herrera said.

Concerned, he called Malibu Dolphin Rescue and was told by Executive Director Mary Frampton that nothing could be done until the carcass washed ashore. De Herrera volunteered to paddle out and bring the dead dolphin ashore. By that time, the dolphins had moved about one-quarter mile west along the beach.

De Herrera paddled out and came within 15 feet of the floating carcass. Although he believes the dolphins were aware of his presence, “for the most part they pretty much ignored me,” he said. The dolphins did, however, prevent him from getting any closer to the carcass for the 20 minutes De Herrera was near them.

“They kind of came up from underneath [the carcass] and pushed it away,” he said. “I got the impression they didn’t want me to intervene in any way.”

Evan Smith also noticed the strange behavior from his home on La Piedra Beach. A little before 8 Friday morning, he saw a dolphin that was “moving funny” about 100 yards offshore. A look through his binoculars showed two dolphins pushing a carcass to the water’s surface.

The dolphin was pretty well decayed, Smith said. “Its rear flipper was mostly gone, its snout was decayed, it looked like scavenger fish got to it. It looked bloated, like it had been dead for awhile.”

De Herrera and Smith were not the first individuals to witness the dead dolphin. Joe Cordaro, a wildlife biologist at the National Marine Fisheries Service, said it was first reported Aug. 9. The dolphin was very well decayed by that point, Cordaro said, suggesting it had been dead for some time prior to that first sighting.

The dolphin was spotted a fourth time two days after De Herrera and Smith’s sighting. Frank Miller stepped outside his home on Malibu Cove Colony Drive Sunday afternoon and noticed a dolphin approximately 50 feet east of his home.

“It started to move,” Miller said. “I thought it was alive because you could see a slight wake.” Miller’s son-in-law came outside to take a look, and the two determined that the carcass was being pushed by two dolphins.

The behavior seems similar to what occurs when a female dolphin gives birth, Cordaro said. On those occasions when the calf does not surface, “dolphins will attempt to float the animal,” he said. “Floating” means that the dolphins attempt to push the calf to the water’s surface to help it breathe. But De Herrera, Smith and Miller agreed that, based on its size, the carcass is that of an adult dolphin.

Cordaro said whether dolphins would attempt to float a dead one is uncertain. “It could be that they will do it with any animal,” he said. “From what I’ve read and seen, they can’t recognize that it’s dead right off the bat. They can’t make that logic step that the animal isn’t alive.”

Because he does not think a dolphin can distinguish between one that is dead or alive, Cordaro said the behavior may possibly be attempts to float the dead dolphin.

Frampton, however, disagrees. She has studied dolphins and believes they possess the capability to determine whether another dolphin is alive. “I think they know exactly that this animal is not alive and that something else is going on,” she said. “This is just very unusual behavior.”

De Herrera, who has come into close contact with dolphins while surfing, said this is the first time in more than 20 years that he has observed this type of behavior.

Smith wonders whether the dolphin’s death was caused by old age or if it could have possibly become tangled in a fishing net.

“I doubt that it was involved in a human-related act,” Cordaro said. Becoming entangled in a fishing net would have separated the dolphins, he said. Although the exact cause of death cannot be determined until an autopsy is performed, it was probably of natural causes. “There’s just a whole slew of diseases and parasites a dolphin can contract,” Cordaro said.

Even if the dolphin does eventually wash ashore, the state of decomposition will make it extremely difficult to determine the cause of death unless there are external markings on the animal, Cordaro said.

The reason for the dolphins’ behavior is even more difficult, if not impossible, to determine.

“It could be the bond is so strong, they’ll just keep pushing it,” Cordaro said. “It could be that because it’s one of their own, they’ll keep tending to it until it washes up on shore. What you’re asking is to get inside the head of a dolphin, and at this point we just don’t know.”

Frampton agrees. “Maybe they do this all the time, but isn’t it interesting that people who study dolphins don’t know what’s going on?” she asked. “It’s just sort of a mystery.”