A National Aquarium curator said a sharp blow from a dolphin's tail shattered the ribs and ruptured the heart of Anore, a 9-year-old beluga whale that died Monday. But animal-rights activists have another explanation.
"Actually, it's captivity that killed her," said Richard O'Barry, the trainer of television's "Flipper" and now a crusader against live whale and dolphin exhibits.
Douglas Messinger, the aquarium's marine mammal curator, said examination Monday night at Johns Hopkins Hospital showed that the 11-foot-long, 1,100-pound animal was probably hit during a 12:35 p.m. training exercise in the main exhibition pool.
No one saw the mishap. But aquarium officials concluded that Anore was injured as she, two other belugas and two dolphins raced around the pool in what was either an aggressive effort to stake out territory or simple horseplay.
About 1 p.m., the beluga was spotted swimming listlessly. By the time trainers swam out to her, she was dead.
"We're all extremely upset and shocked by it," Mr. Messinger said. "Many of us and many of the staff have worked with Anore since the first day she arrived from the aquarium. It's very much like losing a good friend."
Mr. O'Barry, in a telephone interview from Coconut Grove, Fla., said the behavior of the dolphin "has been radically altered by its radically altered habitat. That never would have happened in the wild if they left those dolphins alone." In the open ocean, he said, they would swim away rather than charge the whales.
Daniel Mathews of People for the Ethical Treatment of Animals, which wants the whales and dolphins returned to the ocean, blamed the accident on the exhibition tank.
"When marine mammals are confined in tanks, their sonar signals bounce off the walls and completely disorient them," he said.
But Vicki Aversa, a spokesman for the aquarium, said Anore's death was an accident and accidents can happen anywhere, even in the wild. "We don't feel the habitat, or the Marine Mammal Pavilion or animal care was at fault in any way," she said.
Two dolphins and two beluga whales have died at the National Aquarium in the past decade. The most recent death was that of Illamar, a 7-year-old beluga, who succumbed to gastritis and a disease of the pancreas on Aug. 10, 1989.
Animal-rights advocates and aquarium officials around the country sharply disagree over how long marine mammals survive in captivity.
Ben White of the Sea Shepherd Society, for example, said statistics show that belugas live about four years after being put in aquarium tanks, while dolphins live about 4 1/2 .
Mr. O'Barry cited a 1990 Orlando Sentinel series that, he said, found one-third of the Atlantic bottlenose dolphins captured or born into captivity in the 1980s are dead. In the wild, he said, they can survive up to 45 years.
But Jim Bonde, a spokesman for Marine World Africa USA, which has 14 Atlantic bottlenose dolphins at its facility in Vallejo, Calif., said, "We've found that our dolphins are living as long in captivity, if not longer, as in the wild."
Mr. Messinger said belugas also "do very well in oceanariums, for the most part." He said they live about 25 to 30 years in the wild, and "the New York aquarium has an animal that's coming up on 20 years of age."
Ms. Aversa and Mr. O'Barry agreed on one point: Baltimore's aquarium does not have an unusually high number of deaths among whales and dolphins.
Anore was captured in the Churchill River near the Hudson Bay in Canada in 1985 at the age of 3.
She was injured, Mr. Messinger said, after the end of the noontime show, during a five-minute training session for the three whales and two dolphins, Akai, 17 years old, and Nalu, 19.
During the training session, Mr. Messinger said, the whales began chasing the two frisky, powerful dolphins, who average about 8 1/2 feet long and about 450 pounds each.
The dolphins, which can speed through the water at up to 22 miles per hour, then turned and chased the whales around the pool.
"We saw what we thought was somewhat aggressive behavior from the dolphins towards the whales," Mr. Messinger said.
"At that time we removed the dolphins from the pool. The beluga whales came back to their trainers and appeared normally and ate normally," he said.
About 20 minutes later, Anore was spotted swimming listlessly. She died within minutes.
Trainers have been putting the belugas and dolphins in the exhibition tank for a few minutes at a time for the past three months, in an effort to get them used to one another, Mr. Messinger said.
Eventually, the aquarium hoped to exhibit the animals together in the tank during the daily shows.
The dolphins and whales occasionally chase one another during training sessions. No one is sure why.
"Sometimes it's difficult to interpret," Mr. Messinger said. "Sometimes it is play. Sometimes it may be testing each other's territory."
He added: "I don't think these animals are out to mortally wound each other. I think that during this chase behavior, aggressive or otherwise, this accident occurred."
The aggressive behavior, said Mr. White of Sea Shepherd, might explained by the fact that wild belugas, which live in cold
northern waters, never encounter Atlantic dolphins, who live in warmer latitudes.
But Mr. Messinger pointed out that belugas and dolphins swim in the same tank together in shows at marine parks in Connecticut, Florida, Texas and California.
Aquarium officials checked the tails of the two dolphins but did not find bruises.
Trainers were unable to figure out which one struck Anore.
Ms. Aversa said the aquarium is not planning changes in the wake of Anore's death -- except to "reassess" efforts to put whales and dolphins in the tank together during the marine mammal show.
Criticism of the aquarium is misdirected, she added, because it helps get people interested in preserving marine mammals by giving them a firsthand look.
"I feel like we're part of the solution to the environmental concerns, not the problem," she said. "The activists are going about things a little differently than we are, but we all share the same goals."