dozen or more people reported witnessing one of the world's rarest wildlife phenomena when an orca rode a wave onto Indian Beach in Trinidad and seized a seal.
Researchers said it may be the first recorded occurrence of its kind in the United States, although similar behavior has been witnessed in British Columbia, Argentina and islands in the Indian Ocean.
Ruby Rollings from the Seascape Pier was alerted to the presence of the killer whales in Trinidad Bay just before lunch Tuesday, and grabbed a pair of binoculars to watch. A large adult orca was swimming in the bay with a juvenile orca and two much smaller orcas, she said.
After a while, Rollings said she say the larger whale ride a wave partway onto the beach and seize a harbor seal in its teeth.
"He bit it, then he slammed the seal against the sand," Rollings said.
Rollings said the whale left the seal on the beach, then headed back into the bay, and eventually out to sea.
Such behavior is rare among orcas. Washington-based Orca Network Director Howard Garrett was surprised to hear of the sighting and said the research community is very interested.
"That's pretty amazing," Garrett said.
Several other experts the Times-Standard spoke with said they had not heard of a hunt like it in North America. Brad Hanson, a wildlife biologist with the National Marine Fisheries Service, said the fact that it doesn't happen more often has been a topic of discussion among researchers. He didn't doubt the accuracy of the account.
"It's hard to miss a killer whale when it's halfway out of the water," Hanson said.
John Ford, a whale scientist with Fisheries and Oceans Canada, said similar sightings have been reported in British Columbia, although he said it's a rare occurrence.
The technique is incredible to watch, but it has downfalls. With the enormous weight of the orca flopped onto the beach, it's possible for the animal to get stuck. Female orcas can weigh 7,000 pounds, and males up to 9,000 pounds.
"It's a risky venture," Garrett said.
It's something few people will ever see in their lives. Beach hunting has been documented in Argentina's Patagonia and the Crozet Islands in the Indian Ocean, Garrett said.
But the intelligent animals are innovative: Orcas have been seen tipping ice sheets to knock seals into the water in Antarctica, and in New Zealand killer whales are known to pluck stingrays off the sea floor and toy with them at the surface, he said.
Humboldt State University Marine Laboratory technicians Alyssa Firkus and Susan Sebring were taking water samples by Trinidad Pier when they heard a man shout that there were orcas in the bay. They went to look, and were offered a ride on the water taxi.
Firkus said they watched as the small group of orcas swam toward Indian Beach. The largest whale swam up on shore, half exposed, and thrashed around before backing into the water again, she said.
"That's been my dream since I was 2 years old to see that," Firkus said.
The group of whales then headed toward the boat launch, around the rock near the pier, under the pier and then out to sea, Firkus said.
A pod, or group, of orcas was spotted offshore by the HSU research vessel Coral Sea not long ago, said lab aquarium caretaker Grant Eberle, and orcas have been seen off the mouth of the Klamath River. A group of about 20 were seen off Newport, Ore., within the past two weeks, as well.
There are three types of orcas in the eastern North Pacific. One type eats just about any marine mammal it can get hold of, from seals to whales. Another focuses on fish, especially chinook salmon. Another group stays generally 25 to 30 miles offshore, in the rich continental shelf area, where tuna and sharks are key parts of their diet. The types don't interbreed, even though they sometimes mix.
Source: Mercurynews.com
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