Rare Pacific right whales are back near US coast


This video says about itself:

31 October 2011

National Geographic photographer Brian Skerry describes a magical but risky experience photographing an enormous [southern] right whale off the coast of New Zealand.

From the Scripps Institution of Oceanography at the University of California in San Diego, USA:

Research Highlight: The Sound of Hope

Rare whale species heard off continental U.S. for the first time in more than 20 years

Feb 09, 2015

Once upon a time in the ocean, North Pacific Right Whales thrived.

Their unique calls could be heard across the seas from Asia to North America. Intense whaling activities in the nineteenth and twentieth centuries changed all that, decimating their population. Mid-twentieth century recovery efforts—backed by international whale-protection laws—were hampered by illegal Russian whaling in the 1960s and ’70s.

Today, only several hundred North Pacific Right Whales remain, divided into two groups: one in the Sea of Okhotsk off Russia and a second in the eastern Bering Sea off Alaska. For years scientists have been seeking any sign of the Bering Sea group because it is considered one of the most critically endangered cetacean populations in the world with only about 30 animals remaining.

Now, Scripps Institution of Oceanography at UC San Diego researchers have reported some good news for the precarious population with a glimmer of hope that its numbers may be rebounding. A team led by Scripps researcher Ana Širović recorded the first evidence of these animals off the continental United States in decades.

Širović and her colleagues analyzed marine mammal sounds recorded in 2013 with four High-frequency Acoustic Recording Packages (HARPs), underwater microphones developed at Scripps that capture the calls and clicks emitted by various species. North Pacific Right Whales are known to produce distinctive low-frequency sounds—acoustically classified as up-calls, down-calls, gunshots, screams, and moans—that can travel across vast distances in the ocean.

To their surprise, the team discovered two Right Whale calls in HARP data recorded at Quinalt Canyon off Washington State, the first off the continental U.S. in more than 20 years, and separately at Quinn Seamount in the Gulf of Alaska.

“We had been looking for Right Whales for some time, knowing that the chances of hearing them were pretty small,” said Širović. “So it was very exciting and I was quite surprised when we heard their calls. It was a good day.”

“Our ability to detect rare species, such as the North Pacific Right Whale, has been dramatically improved by the development of new technology for listening underwater,” said Scripps Oceanography Professor John Hildebrand, a co-author of the study, published in Marine Mammal Science.

In 2013, two Right Whales were visually identified off British Columbia, Canada, marking the first such sightings that were made in the area in more than 60 years. Širović said there is no way of definitively knowing whether the animals seen were the same as the ones that were heard.

Nevertheless, the recent acoustic recordings and visual sightings may be good signs for the population of this rare animal and these instances “may offer a sliver of hope for its eventual recovery,” the researchers said in the report.

“Given the rarity of this species, and very few visual or acoustic sightings that have occurred outside the Bering Sea, our detections are an important indicator that this population is using a larger oceanic area of the North Pacific,” said Širović. “I think we are all doing this kind of work hoping to find good things to report. This was one of those good news moments. It was a happy finding.”

Shame-faced crabs of the Pacific


This video from the sea near Samal island in the Philippines is about a shame-faced crab, eating a Terebra maculata mollusk.

From Australian Geographic:

Shame-faced crab has nothing to hide about

November 27, 2014

It may look like its hiding its face out of embarrassment, but this crab has everything to be proud of

by Becky Crew

I DON’T THINK I’ve ever loved another crab as much as I love this crab right now. He’s so embarrassed he can barely even look at us. He’s so ashamed that he has to cover his face with his two humungous front pincers. Don’t feel bad, shame-faced crab, we don’t care what you did; you’re just a crab.

Found at depths of up to 50m below the surface of the Indo-Pacific, these large crabs range as far as Madagascar to west, Japan to the north, and throughout Indonesia, Papua New Guinea and New Caledonia a little closer to home.

Despite their looks and their funny little name, shame-faced crabs (Calappa calappa) are no victims. These highly armoured creatures are like walking tanks, their 15cm-long, burnt-caramel-coloured carapace acting as the perfect cover from predators until they have a chance to bury themselves right into the sand. Watch the video [above], it’s almost a little creepy how it inches deeper and deeper into the ocean floor, until all that’s left is a pair of beady eyes and the upper edges of its jagged pincers, looking just like a monster face peering up at you.

Shame-faced crabs don’t have to worry too much about predators, but keep themselves hidden during the day all the same. At night they turn to hunting, targeting little mollusks such as clams, oysters and sea snails. While hard-shelled prey like these present a challenge to many would-be predators, the shame-faced crab has evolved to deal with them expertly.

Of its two huge, meaty pincers, the right one is perfect for cracking into its prey’s tough outer shell. It’s equipped with a single, specially curved tooth that works with the flat surface of the pincer just like a can-opener to cut into its prey. Then the left pincer, which is longer, smaller, and sharper, takes over to extract the flesh from inside.

Being elegant about how you eat your dinner is nothing to be ashamed about, shame-faced crab. Just because the rest of the ocean is filled with barbaric rubes that wouldn’t know a utensil if it landed on them. Chin up, little man!

Coconut crabs in Hawaii: here.

Disco clam light, new research


This video from California in the USA is called Disco Clams Light Up the Ocean Floor.

From Wildlife Extra:

The secret of the disco clam’s light show is revealed

The Ctenoides ales file clam, also known as the disco clam, is one of the few creatures to use silica micro-structures to reflect light, according to new research published in the Journal of the Royal Society Interface.

The clam does it so well that for years divers and scientists alike believed that it was generating its unique electric display with light-producing chemical reactions known as bioluminescence.

Lindsey Dougherty, a PhD student at the University of California, Berkeley, first shattered that idea last year with a series of presentations showing that the lips were lined with reflective silica spheres.

For the new study, Dougherty and her colleagues used an electron microscope to look at the spectral signature of the structure of the clam’s lip tissue.

On one side were those microscopic balls of silica — the primary element in glass and quartz. The other side was dark, and only reflected light on the red-end of the visible light spectrum.

Because red light doesn’t transmit well underwater, the dark side of the clams’ lips are effectively non-reflective.

Conversely, the silica-side reflects 85 to 90 per cent of all white light when underwater.

“They’re almost ideal reflectors in blue-green water environments,” said Dougherty.

The team confirmed this by using computer models to see how the spheres’ structures reflected light at four different wavelengths.

Using a high-speed camera, they were able to see exactly how the clams make the flash: by rapidly rolling and unrolling their lips, exposing the dark and reflective sides at a rate of about two times per second.

Disco clams can be found all the way from Australia to Indonesia in water from 10 to 160ft deep.

Even in shallow waters, the clams tend to squirrel themselves away into relatively dark nooks, which explains why it seemed so natural to think that their display was bioluminescent.

From an evolutionary perspective, lightning lips are a pretty costly adaptation. They need special muscles to control the furling motion, and silica is a rare element in the ocean.

Dougherty said there are three possibilities: The lips are to lure in mates, attract prey, or ward off predators.

In the future, she’s going to be researching the clams’ eyes (they have up to 40). Knowing how the clams see could unlock the secret behind their most prominent light-show feature.

See also here.

New sponge species discovery in the Pacific


This video from California in the USA says about itself:

Four new species of carnivorous sponges: Adapting to life in the deep sea

14 April 2014

This video describes four new species of carnivorous sponges from the Northeast Pacific Ocean that were discovered by MBARI scientists. Carnivorous feeding in sponges is an adaption to the food poor deep-sea environment, where filter feeding — the typical way sponges feed — is energetically expensive. Instead, these sponges trap small crustaceans with microscopic hooks. Once trapped, sponge cells mobilize, engulf the prey, and rapidly digest it. In addition to consuming small crustacean prey, one of these species appears to be consuming methane-oxidizing chemosynthetic bacteria.

For more information visit here.

From Wildlife Extra:

Four new species of killer sponges discovered

April 2014: Four new species of carnivorous (killer) sponges living on the deep seafloor, from the Pacific Northwest to Baja California have been discovered by scientists from the Monterey Bay Aquarium Research Institute.

It was only discovered that some sponges are carnivorous about 20 years ago. Unlike other sponges most carnivorous sponges do not have specialised cells called choancytes, whose whip-like tails move continuously to create a flow of water which brings food to the sponge. Therefore these sponges, explains lead marine biologist Lonny Lundsten “trap larger, more nutrient-dense organisms, like crustaceans, using beautiful and intricate microscopic hook.”

These animals look more like bare twigs or small shrubs covered with tiny hairs. But the hairs consist of tightly packed bundles of microscopic hooks that trap small animals such as shrimp-like amphipods. Once an animal becomes trapped, it takes only a few hours for sponge cells to begin engulfing and digesting it. After several days, all that is left is an empty shell.The four new sponges are named as Asbestopluma monticola, (which was collected from the top of the extinct underwater volcano Davidson Seamount off the coast of central California), Asbestopluma rickets (named after the marine biologist Ed Ricketts), Cladorhiza caillieti, (found on recent lava flows along the Juan de Fuca Ridge, a volcanic ridge offshore of Vancouver Island), and Cladorhiza evae, which was found far to the south, in a newly discovered hydrothermal vent field along the Alarcon Rise, off the tip of Baja California.

Harmless dye reveals how incredibly efficient sea sponges are at pumping and straining water: here.

Prehistoric Pacific marine mammals discoveries


This video is called Whales evolution.

Not only news about big land mammals during the Ice Age … also about big marine mammals before the Ice Age.

From the University of Otago in New Zealand:

Strange marine mammals of ancient North Pacific revealed

February 5, 2014

Summary:

The pre-Ice Age marine mammal community of the North Pacific formed a strangely eclectic scene, new research reveals. Studying hundreds of fossil bones and teeth excavated from the San Francisco Bay Area‘s Purisima Formation, scientists have put together a record of 21 marine mammal species including dwarf baleen whales, odd double-tusked walruses, porpoises with severe underbites and a dolphin closely related to the now-extinct Chinese river dolphin.

The pre-Ice Age marine mammal community of the North Pacific formed a strangely eclectic scene, research by a Geology PhD student at New Zealand’s University of Otago reveals.

Studying hundreds of fossil bones and teeth he excavated from the San Francisco Bay Area’s Purisima Formation, Robert Boessenecker has put together a record of 21 marine mammal species including dwarf baleen whales, odd double-tusked walruses, porpoises with severe underbites and a dolphin closely related to the now-extinct Chinese river dolphin.

Among his finds, which were fossilized 5 to 2.5 million years ago, is a new species of fossil whale, dubbed Balaenoptera bertae, a close relative of minke, fin, and blue whales.

Mr Boessenecker named the whale in honour of San Diego State University‘s Professor Annalisa Berta, who has made numerous contributions to the study of fossil marine mammals and mentored many students.

Although an extinct species, it belongs within the same genus as minke and fin whales, indicating that the Balaenoptera lineage has lasted for 3-4 million years. Balaenoptera bertae would have been approximately 5-6 meters in length, slightly smaller than modern minke whales, Mr Boessenecker says.

His findings appear in the most recent edition of the international journal Geodiversitas.

The publication represents eight years of research by Mr Boessenecker, who was 18 in 2004 when he was tipped off by a local surfer about bones near Half Moon Bay. When he discovered the fossil site, he was astonished by the numerous bone-beds and hundreds of bones sticking out of the cliffs.

He excavated the incomplete skull of Balaenoptera bertae during early field research there in 2005 and it was encased in a hard concretion that took five years to remove.

“The mix of marine mammals I ended up uncovering was almost completely different to that found in the North Pacific today, and to anywhere else at that time,” he says.

Primitive porpoises and baleen whales were living side-by-side with comparatively modern marine mammals such as the Northern fur seal and right whales. And species far geographically and climatically removed from their modern relatives also featured, such as beluga-like whales and tusked walruses, which today live in the Arctic, he says.

“At the same time as this eclectic mix of ancient and modern-type marine mammals was living together, the marine mammal fauna in the North Atlantic and Southern Ocean were already in the forms we find today.”

Mr Boessenecker says this strange fauna existed up until as recently as one or two million years ago. Its weirdness was likely maintained by warm equatorial waters and barriers to migration by other marine mammals posed by the newly formed Isthmus of Panama, and the still-closed Bering Strait.

“Once the Bering Strait opened and the equatorial Pacific cooled during the Ice Age, modernised marine mammals were able to migrate from other ocean basins into the North Pacific, leading to the mix we see today,” he says.

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