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Posts Tagged ‘shark’

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Art: Olga Shvartsur/Fine Art America
Humpback whale and baby. Recently, a humpback whale appeared to intentionally protect a researcher from a tiger shark.

A scientist who studies whales underwater was astonished and more than a little frightened in September 2017 when a whale kept pushing her toward her boat. After her colleagues pulled her to safety, she saw that in the other direction a dangerous tiger shark was lurking. The researcher believes that the whale was intentionally trying to protect her. Other scientists argue that whales aren’t altruistic.

I say, Who cares? The point is the whale’s action moved the diver away from danger, and she is grateful.

Sarah Gibbens writes at the National Geographic, “For 28 years, Nan Hauser has been researching and diving with whales. The biologist is the president and director of the Center for Cetacean Research and Conservation. … During a trip to look at whales in the Cook Islands in the South Pacific last September, Hauser says she had an encounter unlike any she had experienced before.

“A humpback whale, a marine mammal capable of weighing 40 tons and growing 60 feet long, swam toward Hauser. For ten minutes, it nudged her forward with its closed mouth, tucked her under its pectoral fin, and even maneuvered her out of the water with its back. …

” ‘I was prepared to lose my life,’ she says. ‘I thought he was going to hit me and break my bones.’

“In addition to conducting research, Hauser says she was also in the Cook Islands to work on a nature film, so at the time the whale approached, both she and a fellow diver were armed with cameras. Hauser’s point-of-view footage shows just how persistently the whale nudged her. A second whale can also be seen lurking just behind the first.

“When she finally made it out of the water and up onto her boat — bruised and scratched from the barnacles on the whale — Hauser saw a third tail moving from side-to-side.

” ‘I knew that was a tiger shark,’ she says.

“Now, after viewing the footage and reflecting on the whole harrowing experience, Hauser concludes that the whale who nudged her likely exhibited an extraordinary example of altruism. …

“Hauser’s retelling isn’t the first time scientists have questioned whether humpback whales can show signs of altruism. A 2016 study in the journal Marine Mammal Science looked at 115 instances from the past 62 years in which humpbacks interfered with a pod of hunting orcas.

“Banding together, humpbacks were seen effectively protecting their calves. But there were also examples of humpbacks showing the same behavior to protect other species of whales, seals, and sea lions. …

“Martin Biuw from the Institute of Marine Research in Nowary is skeptical of Hauser’s claim that altruism is at play in the video. Hauser had speculated the whale was male, but Biuw believes it appears to be a female.

” ‘If that is the case, it is possible that she may show protective behavior towards a human (or other animal for that matter) if she has for instance recently lost her calf,’ he says.

“Biuw explained that hormonal changes could have spurred the whale to show protective behavior.” Oh, ha, ha, hormonal changes? Good grief, give me a break.

More at the National Geographic, here.

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I have been learning all sorts of strange marine facts from Suzanne and Erik’s children. They are hooked on a video series called The Octonauts, which features cartoon characters living in the sea. One piece of wisdom from the grandchildren was about wraith-like creatures called siphonophorae, a word that gives me trouble but rolls right off a child’s tongue. Siphonophorae live even deeper in the ocean than the Octonauts and some are light emitting, which makes for a good storyline.

All this leads me to another light-emitting sea creature recently discovered near Hawaii, a shark.

Lauren Smith writes at the Guardian, “Light emitted by a new species of lanternshark, Etmopterus lailae, is camouflage and helps them to hunt, communicate and find partners. Early [in 2017] a new species of deep water shark, Etmopterus lailae, was discovered in waters surrounding the Northwestern Hawaiian Islands in the Pacific Ocean.

“Measurements of external features, teeth, vertebrae and intestines, along with specific external markings and patterns confirmed that it was indeed a new species – a member of the lanternshark family. Lanternsharks (Etmopteridae) are one of the most species-rich shark genera. …

“The lanternsharks are one of two deep sea shark families to possess the ability to bioluminesce – in other words, they are able to glow in the dark. The other shark family with the ability to do this are the kitefin sharks (Dalatiidae). This family houses the infamous cookie cutter shark, which was known for its impressive ability to disable US Navy submarines in the 70s and 80s. …

“Bioluminescence is the emission of light as a result of a biochemical reaction. In contrast to fluorescence and phosphorescence, bioluminescenct reactions do not require the initial absorption of sunlight or other electromagnetic radiation by a molecule or pigment to emit light. …

“Bioluminescence in vertebrates is found exclusively among fishes living in marine environments. At present the only known terrestrial animals capable of bioluminescence are arthropods. …

“It is also worth noting that bioluminescence is not just exhibited by deep sea dwellers existing in perpetual darkness. [One study] analysed 17 years of video footage taken from the sea’s surface down to a depths of almost 4000 metres. Observations showed that the percentage of bioluminescent animals is remarkably uniform regardless of depth.”

More at the Guardian, here.

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