• 'Super mega-pod' of dolphins spotted off San Diego coast

    Photo Courtesy of Antonio Ramirez

    Antonio Ramirez, who was aboard a Hornblower Cruise on Thursday, snapped this photo of the dolphins swimming in a "super mega-pod."

    By Sarah Grieco, NBCSanDiego.com

    Thousands of dolphins spanning across seven miles of ocean were sighted off the coast of San Diego on Thursday, a boat captain told NBC 7 San Diego.

    Capt. Joe Dutra of Hornblower Cruises said he saw a “super mega-pod” of common dolphins Thursday around noon while he was on his daily tour. He said the pod was more than seven miles long and five miles wide.

    It's likely the mega-pod of dolphins were following food, such as sardines or herring. But whatever the reason they congregated off the coast of California, scientists say there's no doubt they were communicating with one another. NBC's Diana Alvear reports.

    Dutra said the boat tour followed the pod for more than an hour and said he’s never seen anything like it.

    “When you see something that is honestly truly beyond belief,” the captain said.

    Guests aboard the boat started screaming and pointing when they first saw the school of adult and juvenile common dolphins. Dutra estimated there were about 100,000 dolphins swimming in the area.

    For more, visit NBCSanDiego.com

    “They were coming from all directions, you could see them from as far as the eye can see,” he said. “I’ve seen a lot of stuff out here… but this is the biggest I’ve ever seen, ever.”

    Whale and dolphin watching tours have done particularly     well this year, with dozens of animal sightings reported.

    Marine mammal expert Sarah Wilkin said the reason the large pod might be there is because there’s plenty of food in the area, including sardines, herring and squid.

    “They’re attracted to kind of the same thing, they might wind up in the same place,” she said.

    Though dolphins typically travel in groups of 200 or less, Wilkin said “super-pods” are not unheard of.

    “They’re definitely social animals, they stick together in small groups,” she said. “But sometimes, the schools come together.”

    Dutra, who’s been boating for decades, said he felt lucky to enjoy such a rare phenomenon.

    “You had to be there to experience it,” he said.  “It was truly spectacular.”

  • 40 dolphins die, 19 survive in Cape Cod strandings

    IFAW via Reuters

    Two dolphins are prepared for release Monday into Cape Cod Bay.

    By msnbc.com staff and news services

    BOSTON -- Nineteen dolphins that stranded themselves along Cape Cod have been treated and released, but several dozen others have perished since the string of strandings began last Thursday.

    Eight that stranded alive did not survive, said Katie Moore, manager for marine mammal rescue at the International Fund for Animal Welfare, while another 32 washed ashore already dead.

    Of the 19 survivors, one was a calf and another a pregnant mom.

    Strandings typically happen from January to April, but the pattern this year is unlike past years, when just one dolphin or a group would be found on a single beach, she said.

    "I've been doing this for 15 years and this is only the second season I've seen it like this," she said.

    Julia Cumes / AP

    A dolphin is given a hearing test before being released back into Cape Cod Bay at Scusset Beach on Saturday.

    "It feels like stranding after stranding after stranding," Moore added. "It's definitely out of the ordinary."

    The dolphins began beaching themselves on Thursday, with a single dolphin stranded near the town of Wellfleet, said IFAW spokeswoman Kerry Branon.

    On Saturday, the busiest day for rescuers, at least 37 dolphin were found spanning five towns along 20 miles of Cape Cod, Branon said.

    Cape Cod is among the top locations for the phenomenon worldwide, she said. Beaching of dolphins has been happening for centuries, but researchers are still trying to determine what brings the dolphins to Cape Cod Bay this time of year.

    The group actions tend to happen, in part, because dolphins operate with a group mentality, where many others may follow one animal toward shallow water, IFAW said.

    The animals, which tend to get stuck on the bay side of the hook-shaped Cape Cod, are assessed by rescuers and then taken to deeper water on the ocean side and released.

    Marine biologists check for signs of stress and body condition, among other factors, and tag the dolphins with an identifier before release.

    A handful of animals have also been affixed with a tag to track movement and transmit data to researchers, Branon said.

    "We also were able to test the hearing on one animal as well ... important data for our project which will hopefully aid in conservation measures to protect marine mammals from ocean noise," Moore said in a statement.

    Moore said this year's series of dolphins stranded on beaches reminded her of the 2005-2006 winter, when dolphins beached themselves over a 40-day period.

    Reuters contributed to this report.

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