Electric eels solving energy problems


This 2017 video is called Electric eel immobilized a huge crocodile.

By Maria Temming:

Electric eels provide a zap of inspiration for a new kind of power source

Battery-like devices mimic how a charge builds up in the animal’s cells

1:22pm, December 13, 2017

New power sources bear a shocking resemblance to the electricity-making organs inside electric eels.

These artificial electric eel organs are made up of water-based polymer mixes called hydrogels. Such soft, flexible battery-like devices, described online October 13 in Nature, could power soft robots or next-gen wearable and implantable tech.

“It’s a very smart approach” to building potentially biocompatible, environmentally friendly energy sources and “has a bright future for commercialization”, says Jian Xu, an engineer at Louisiana State University in Baton Rouge not involved in the work.

This new type of power source is modeled after rows of cells called electrocytes in the electric organ that runs along an electric eel’s body. When an eel zaps its prey, positively charged potassium and sodium atoms inside and between these cells flow toward the eel’s head, making each electrocyte’s front end positive and tail end negative. This setup creates a voltage of about 150 millivolts across each cell. The voltages of these electrocytes add up, like a lineup of AAA batteries powering a flashlight, explains Michael Mayer, a biophysicist at the University of Fribourg in Switzerland. Collectively, an eel’s electrocytes can generate hundreds of volts.

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Ocean sunfish, new study


This video says about itself:

Occurred September 26, 2013 / Ilha de Santa Maria, Açores, Portugal

This rare footage of a gigantic sunfish was captured on film by photographer Miguel Pereira off the coast of Portugal. The huge creature dwarfs the divers as it swims past. The slow-moving fish and clear water allow for some spectacular close-ups of this amazing animal.

“A few days before, my camera was damaged when the underwater housing flooded. The bad luck was compensated when diving with a GoPro I saw the giant Sunfish almost at surface level and practically static. The Sunfish seemed not to be bothered by our presence at all and followed us for 15 minutes.” -Miguel Pereira

From ScienceDaily:

World’s heaviest bony fish identified and correctly named

Researchers clear up confusion between taxonomy of multiple species of ocean sunfishes

December 5, 2017

Japanese fish experts have identified and clarified the biological name of the world’s heaviest bony fish ever caught. The 2,300 kilogram whopper is a Mola alexandrini bump-head sunfish, and not, as originally thought, a member of the more commonly known Mola mola ocean sunfish species. The study was led by Etsuro Sawai of Hiroshima University and is published in Ichthyological Research, which is the official journal of the Ichthyological Society of Japan. The journal is published by Springer.

Bony fish have skeletons made of bone rather than cartilage, as is the case for sharks or rays. Ocean sunfishes count among the world’s largest bony fish, and have for centuries attracted interest from seafarers because of their impressive size and shape. Specimens can measure up to three meters (total length), and many weighing more than two thousand kilograms have been caught. Instead of a caudal fin, sunfish have a broad rudder-like lobe called a clavus.

In this study, Sawai and his team referred to more than one thousand documents and specimens from around the world — some of which date back 500 years. Their aim was to clarify the scientific names for the species of the genus Mola in fish.

Ocean sunfishes can be classified into three species which Sawai’s team temporarily called Mola species A, Mola species B, and Mola species C, respectively. Of the three species, the scientific name of Mola species C was officially named Mola tecta in July 2017.

In this study, the researchers studied, dissected and measured 30 specimens of the remaining two Mola species (Mola species A and Mola species B) including fresh and preserved samples from different collections in the world. Information was obtained from photographs and from historic and recent records. The team set out specific morphological characteristics, and made notes on the distribution of the different species. This led them to conclude that the species names Mola mola (Mola species B) and Mola alexandrini (Mola species A) should be used. They also proposed “bump-head sunfish” as the new common name for Mola alexandrini because of the very prominent shape of its head.

“For the same reason, we adopt the already proposed Japanese common name Ushi-manbo. ‘Ushi’ means ‘cow’, and refers to the head profile of the fish,” Sawai explains.

They also solved a case of mistaken identity. The Guinness World Records lists the world’s heaviest bony fish as Mola mola. However, Sawai’s team found a female Mola alexandrini specimen of 2,300 kilogram and 2.72 meter caught off the Japanese coast (Kamogawa, Chiba) in 1996 as the heaviest bony fish ever recorded. Through their investigations, Sawai’s team re-identified it as actually being a Mola alexandrini based on its characteristic head bump, chin bump and rounded clavus although this specimen was identified Mola mola until now.

“Therefore, the world’s heaviest bony fish that has been actually weighed and recorded to date is a specimen of Mola alexandrini, not Mola mola,” says Sawai, who believes that there could be even bigger examples of this species alive in the ocean. In 2004, a 3.32 meter female Mola alexandrini specimen was caught off one of Japan’s islands (Aji Island, Miyagi), but it was not weighed.

Tarpon swimming off Bonaire


This 30 November 2017 video is about tarpon and other fish swimming off Bonaire island in the Caribbean.

Rudolf Mulder made this video.

World’s deepest deep sea fish discovered


This 28 November 2017 video is called New fish species lives 5 miles underwater—a record.

From the University of Washington in the USA:

There’s a deeper fish in the sea

November 28, 2017

The ocean’s deepest fish doesn’t look like it could survive in harsh conditions thousands of feet below the surface. Instead of giant teeth and a menacing frame, the fishes that roam in the deepest parts of the ocean are small, translucent, bereft of scales — and highly adept at living where few other organisms can.

Meet the deepest fish in the ocean, a new species named the Mariana snailfish by an international team of researchers that discovered it. The Mariana snailfish (Pseudoliparis swirei) thrives at depths of up to about 8,000 meters (26,200 feet) along the Mariana Trench near Guam. The team published a paper describing the new species this week in the journal Zootaxa.

“This is the deepest fish that’s been collected from the ocean floor, and we’re very excited to have an official name,” said lead author Mackenzie Gerringer, a postdoctoral researcher at the University of Washington’s Friday Harbor Laboratories. “They don’t look very robust or strong for living in such an extreme environment, but they are extremely successful.”

Snailfish are found at many different depths in marine waters around the world, including off the coast of San Juan Island, where Gerringer is continuing research on the family of fish. In deep water, they cluster together in groups and feed on tiny crustaceans and shrimp using suction from their mouths to gulp prey. Little is known about how these fish can live under intense water pressure; the pressure at those depths is similar to an elephant standing on your thumb.

This new species appears to dominate parts of the Mariana Trench, the deepest stretch of ocean in the world that is located in the western Pacific Ocean. During research trips in 2014 and 2017, scientists collected 37 specimens of the new species from depths of about 6,900 meters (22,600 feet) to 8,000 meters (26,200 feet) along the trench. DNA analysis and 3-D scanning to analyze skeletal and tissue structures helped researchers determine they had found a new species.

Since then, a research team from Japan has recorded footage of the fish swimming at depths of 8,134 meters (26,686 feet), the deepest sighting so far.

“Snailfishes have adapted to go deeper than other fish and can live in the deep trenches. Here they are free of predators, and the funnel shape of the trench means there’s much more food,” said co-author Thomas Linley of Newcastle University. “There are lots of invertebrate prey and the snailfish are the top predator. They are active and look very well-fed.”

A handful of researchers have explored the Mariana Trench, but few comprehensive surveys of the trench and its inhabitants have been completed because of its depth and location, Gerringer explained. These research trips, conducted while Gerringer completed her doctorate at University of Hawai’i at M?noa, involved dropping traps with cameras down to the bottom of the trench. It can take four hours for a trap to sink to the bottom.

After waiting an additional 12 to 24 hours, the researchers sent an acoustic signal to the trap, which then released weights and rose to the surface with the help of flotation. That allowed scientists to catch fish specimens and take video footage of life at the bottom of the ocean.

“There are a lot of surprises waiting,” Gerringer said. “It’s amazing to see what lives there. We think of it as a harsh environment because it’s extreme for us, but there’s a whole group of organisms that are very happy down there.”

Footage from the 2014 research cruise on R/V Falkor will also run in the BBC’s “Blue Planet II” series, which is now airing in the U.K. The research team also filmed another new species on this cruise, the ethereal snailfish, living at great depths in the Mariana Trench. The Mariana snailfish’s location was its most distinguishing characteristic, but researchers also saw a number of differences in physiology and body structure that made it clear they had found a new species. With the help of a CT scanner at the UW’s Friday Harbor Laboratories, the researchers could look in close digital detail to study elements of the fish.

The authors acknowledge the broad collaboration needed for deep-sea science, particularly in this discovery, and decided the new fish’s scientific name should reflect that collaborative effort. The fish is named after a sailor, Herbert Swire, an officer on the HMS Challenger expedition in the late 1800s that first discovered the Mariana Trench.

Philippines coral reef, video


This video about the Philippines says about itself:

Explore One of the Most Pristine Coral Reefs in the World | National Geographic

27 nov. 2017

This is one of the world’s most pristine reefs—and one of the most biodiverse.

Mexico creates North America’s largest ocean reserve


This April 2017 video from Mexico is called 4K Underwater Video: Revillagigedo Archipelago (Socorro Islands) Scuba Diving.

From the BBC today:

Mexico creates huge national park to protect marine life

The Mexican government has created a large marine reserve around a group of islands home to hundreds of species including rays, whales and sea turtles.

The Revillagigedo Archipelago is a group of volcanic islands off the country’s south-east coast.

With a protection zone of 57,000 square miles (150,000km), it has become the largest ocean reserve in North America.

The move will mean all fishing activity will be banned, and the area will be patrolled by the navy.

It is hoped the move will help populations hit by commercial fishing operations in the area recover.

The park was designated by a decree signed by Mexican President Enrique Pena Nieto. It will also forbid natural resources being extracted from the land or the building of new hotel infrastructure.

The area, which is about 250 miles (400km) south-east of the country’s Baja California peninsula has been described as the Galapagos of North America, because of its volcanic nature and unique ecology.

Sitting on the convergence of two ocean currents, the islands are a hub for open water and migratory species.

It has hundreds of breeds of ocean wildlife, including humpback whales that use the shallow and coastal areas around the islands for breeding.

Last year the Pacific Ocean site was named as a UNESCO world heritage area.

María José Villanueva, the director of conservation of WWF in Mexico, described the move as an “important precedent” to the rest of the world, according to local media.

It follows a similar move by Chile, which created an even bigger ocean reserve in 2015.