Blue hole diving in the Bahamas


This video says about itself:

15 December 2017

Jonathan travels to Andros, an island in the Bahamas, to investigate underwater caves that start in blue holes. A blue hole looks like a pond, but leads into a vast underwater cave system. In the Bahamas, these caves often lead to the ocean. As Jonathan explores the ocean end of the caves, he learns how the two systems are connected.

JONATHAN BIRD‘S BLUE WORLD is an Emmy Award-winning underwater science/adventure program.

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Whale shark Anne’s new world record


This December 2017 video is called BEAUTIFUL COUPLE OF WHALE SHARKS SPOTTED IN THE SAUDI RED SEA.

From the Smithsonian Tropical Research Institute in Panama:

Whale shark logs longest-recorded trans-Pacific migration

April 26, 2018

Summary: A whale shark named Anne swam all the way across the Pacific from Coiba National Park in Panama to the Marianas Trench, setting a record as the longest-recorded migration.

Little is known about the world’s largest living fish, gentle giants reaching 12 meters (40 feet) in length. Researchers from the Smithsonian Tropical Research Institute (STRI) and colleagues tracked a female whale shark from the eastern Pacific to the western Indo-Pacific for 20,142 kilometers (more than 12,000 miles), the longest whale shark migration route ever recorded.

STRI marine biologist Héctor M. Guzmán tagged a female whale shark (Rhincodon typus) near Coiba Island in Panama, the largest island off of the coast of Central America, a National Park, World Heritage Site and marine protected area. His team named the shark Anne for conservationist Anne McEnany, president and CEO of the International Community Foundation (ICF). The multi-year project also tagged 45 additional sharks in Panama with sponsorship from Christy Walton’s Candeo Fund at the ICF, along with STRI and Panama’s science and technology bureau (SENACYT).

Guzmán estimated Anne’s position based on signals from a Smart Position and Temperature (SPOT) tag tethered to the shark, received by the Advanced Research and Global Observation Satellite (ARGOS). The tag only communicates with the satellite when the shark swims near the surface. Anne remained in Panamanian waters for 116 days, then swam toward Clipperton Island (France), nearing Cocos Island (Costa Rica) en route to Darwin Island in the Galapagos (Ecuador), a site known to attract groups of sharks. 266 days after she was tagged, the signal disappeared, indicating that Anne was too deep to track. After 235 days of silence, transmissions began again, south of Hawaii. After a nine-day stay, she continued through the Marshall Islands until she arrived at the Marianas Trench, a canyon in the ocean floor near Guam in the Western Pacific where movie director James Cameron located the deepest point on the Earth’s surface almost 11,000 meters (36,000 feet) below sea level.

Whale sharks dive to more than 1900 meters (6000 feet). But it is unknown what the animal was doing in this area.

“We have very little information about why whale sharks migrate,” said Guzmán. “Are they searching for food, seeking breeding opportunities or driven by some other impulse?”

“Despite being the world’s largest fish, it’s amazing to me how little we know about this species”, said Scott Eckert, co-author and biology professor at Principia College. “When I first began working on them, their taxonomy was debated, and it still wasn’t clear how they reproduced.”

Found in warm, tropical and sub-tropical waters, it is thought that about a quarter of whale sharks live primarily in the Atlantic, whereas about three-fourths live in the Indo-Pacific. Tourists are drawn to sites where 500 or more whale sharks gather: in Oman, Australia, Galapagos, Mexico, Mozambique and the Seychelles. Large groups are also reported from Taiwan, Southern China and the Gujarat coast of India.

Genetic studies show that whale sharks across the globe are closely related, indicating that they must travel long distances to mate. Whale sharks have been tracked for shorter distances along similar routes, but this report is the longest-recorded migration to date and the first evidence of a potential trans-Pacific route. Like Anne, other whale sharks appear to follow the North Equatorial Current for most of the distance. Large females can swim an average of 67 kilometers (about 40 miles) per day.

The whale shark is one of only three known filter-feeding sharks, feeding on plankton, fish eggs, krill, crab larvae as well as small squid and fish (and, accidentally, plastic, which they cannot digest). As such, they are not considered to be particularly dangerous, and tourism companies that offer the opportunity to swim very close to whale sharks are common near areas where they aggregate in large numbers. But their size also attracts fishing boats. They are sought after for their fins and meat, for their teeth (used for crafts and sold to tourists) and for cartilage and oil with purported medicinal value. Juvenile whale sharks often end up as bycatch in tuna and other fisheries.

Whale sharks were classified as endangered in 2016. During the past 75 years, it is estimated that nearly half of the world’s whale sharks have disappeared. In many parts of the world, whale sharks have legal protection, but regulations are often not enforced. Guzman’s data were used to design and draft local and regional policies for the protection of the species. Fishing, capture and sale of whale sharks are prohibited in Panama by Executive Decree No. 9, signed in 2009. In 2014, Panama’s environmental authority passed an additional resolution regulating whale shark watching in Coiba National Park and the Isla Canales de Afuera marine reserve. The resolution includes a Whale Shark Watching Manual but unfortunately, tourism activities are not well organized and the authorities are not present to enforce the regulations.

“Whale sharks in Coiba have already changed their behavior to avoid the surface and tourists”, Guzman said. “These studies are critical as we design international policy to protect transboundary species like the whale sharks and other highly migratory marine species.”

Diving for extinct Megalodon shark teeth


This video from the USA says about itself:

1 December 2017

Jonathan Bird goes to South Carolina with Cameraman Tim to meet Alan Devier, a world-renown shark tooth hunter and dive for fossilized Megalodon shark teeth in the murky depths of the Cooper River.

JONATHAN BIRD’S BLUE WORLD is an Emmy Award-winning underwater science/adventure program.

Mackerel on video


This video is about Atlantic mackerel (Scomber scombrus).

Shark evolution video


This video says about itself:

A timeline Of SHARK EVOLUTION (prehistoric till present day)

12 April 2018

Sharks are 450 million years old and have been on this planet longer than almost any other animal. They have lived through every major mass extinction event and have survived long past many of their competitors. With over 3,000 species spanning nearly half a billion years, sharks are one of the most evolutionarily successful animals to ever live. Tracking their evolutionary history, we can learn about these amazing species and how they came to their modern forms.

Most of the sharks on the planet have developed in the Cenozoic era, except for the truly ancient sharks from the Cretaceous period. The newest shark species to enter the water is the Hammerhead Shark. Hammerhead Shark evolution only dates back about 20 million years. Currently there are around 440 species of shark swimming in our oceans, however every year scientists are finding more unique species.

Time line of shark evolution

1. 514 million years ago : Metaspriginna was the oldest known fish-a sector of all jawed vertebrates.
2. 370 million years ago : Cladoselache was the earliest and most well-known shark. Its jaw was fused to its head.
3. 330 million years ago : Falcaus had a dorsal spine and large eyes w.r.t to its tiny body.
4. 320 million years ago : Stetacanthus had tooth-like skin preventing injury
5. 290 million years ago : Helicoprion had a jaw curved into a swirl shape. By this time sharks were able to grow teeth faster.
6. 180 million years ago : Hybodus had extremely sharp canine teeth and flat grinders in the back like a modern day bull shark.
7. 100 million years ago : Ginsu shark was one of the most modern sharks of its time.
8. 55 million years ago : Otodus was huge (30ft-39ft in length). It was the earliest known relative of all mackerel sharks.
9. 15.9 million years ago : Megalodon, meaning BIG TOOTH was one of the largest and fiercest predators ever. Fossil remains of megalodon suggest that this giant shark reached a length of about 59+ ft.

Dinosaurs extinct, fish survived


This 2017 video is called Fish | Educational Video for Kids.

From the University of California – Los Angeles in the USA:

Marine fish won an evolutionary lottery 66 million years ago

The rapid proliferation of acanthomorphs was a response to a mass extinction

April 17, 2018

Why do our oceans contain such a staggering diversity of fish of so many different sizes, shapes and colors? A UCLA-led team of biologists reports that the answer dates back 66 million years, when a six-mile-wide asteroid crashed to Earth, wiping out the dinosaurs and approximately 75 percent of the world’s animal and plant species.

Slightly more than half of today’s fish are “marine fish“, meaning they live in oceans. And most marine fish, including tuna, halibut, grouper, sea horses and mahi-mahi, belong to an extraordinarily diverse group called acanthomorphs. (The study did not analyze the large numbers of other fish that live in lakes, rivers, streams, ponds and tropical rainforests.)

The aftermath of the asteroid crash created an enormous evolutionary void, providing an opportunity for the marine fish that survived it to greatly diversify.

“Today’s rich biodiversity among marine fish shows the fingerprints of the mass extinction at the end of the Cretaceous period“, said Michael Alfaro, a professor of ecology and evolutionary biology in the UCLA College and lead author of the study.

To analyze those fingerprints, the “evolutionary detectives” employed a new genomics research technique developed by one of the authors. Their work is published in the journal Nature Ecology and Evolution.

When they studied the timing of the acanthomorphs’ diversification, Alfaro and his colleagues discovered an intriguing pattern: Although there were many other surviving lineages of acanthomorphs, the six most species-rich groups of acanthomorphs today all showed evidence of substantial evolutionary change and proliferation around the time of the mass extinction. Those six groups have gone on to produce almost all of the marine fish diversity that we see today, Alfaro said.

He added that it’s unclear why the other acanthomorph lineages failed to diversify as much after the mass extinction.

“The mass extinction, we argue, provided an evolutionary opportunity for a select few of the surviving acanthomorphs to greatly diversify, and it left a large imprint on the biodiversity of marine fishes today”, Alfaro said. “It’s like there was a lottery 66 million years ago, and these six major acanthomorph groups were the winners.”

The findings also closely match fossil evidence of acanthomorphs’ evolution, which also shows a sharp rise in their anatomical diversity after the extinction.

The genomic technique used in the study, called sequence capture of DNA ultra-conserved elements, was developed at UCLA by Brant Faircloth, who is now an assistant professor of biological sciences at Louisiana State University. Where previous methods used just 10 to 20 genes to create an evolutionary history, Faircloth’s approach creates a more complete and accurate picture by using more than 1,000 genetic markers. (The markers include genes and other DNA components, such as parts of the DNA that turn proteins on or off, and cellular components that play a role in regulating genes.)

The researchers also extracted DNA from 118 species of marine fish and conducted a computational analysis to determine the relationships among them. Among their findings: It’s not possible to tell which species are genetically related simply by looking at them. Seahorses, for example, look nothing like goatfish, but the two species are evolutionary cousins — a finding that surprised the scientists.

“We demonstrate this approach works, and that it sheds new light on evolutionary history for the most species-rich group of marine vertebrates”, Alfaro said.

Marine animals discoveries off Indonesia


This video says about itself:

Diving in Bali is a document of an extraordinary expedition I made to Indonesia’s magical island of Bali in 2006 with Aquamarine Diving.

From Tulamben’s awesome USAT Liberty wreck, to the reef manta rays of Nusa Penida, via the fascinating macro marine life of Tulamben and Seraya Secrets, the footage covers the breadth of Bali’s fascinating underwater world.

The video features 158 species of marine life, and their common and scientific names are available by turning on the captions with the CC button under the video.

Viewers can now contribute subtitles for the marine life names in this video in many languages. Find out more here.

From Tulamben there is footage of the wreck of the USAT Liberty in both day time and night time, including the humphead parrotfish that spend the night there. Also from Tulamben are numerous marine live encounters from dives at the Drop-Off and the Coral Garden.

Just around the corner we make a dive at Seraya Secrets, a macro hotspot where I encountered seahorses and nudibranchs. From Padangbai on the east coast of Bali we have footage from The Blue Lagoon and Pura Jepun. From the island of Nusa Penida we have the manta ray cleaning station, Manta Point, and Ped.

From the National University of Singapore:

More than 12,000 marine creatures uncovered during West Java deep-sea exploration

Over a dozen new species of crabs, prawns and lobsters discovered; over 40 new records for Indonesia

April 17, 2018

Despite a stormy start thanks to Cyclone Marcus, scientists who participated in the South Java Deep Sea Biodiversity Expedition 2018 (SJADES 2018) had collected more than 12,000 creatures during their 14-day voyage to survey the unexplored deep seas off the southern coast of West Java, Indonesia.

The expedition team, consisting 31 researchers and support staff, were led by Professor Peter Ng, Head of the Lee Kong Chian Natural History Museum of the National University of Singapore (NUS), and Professor Dwi Listyo Rahayu, Senior Research Scientist at the Research Center for Oceanography (RCO) of the Indonesian Institute of Sciences (LIPI). The NUS research team comprises scientists from the Lee Kong Chian Natural History Museum and the Tropical Marine Science Institute.

Some 800 species from over 200 families of sponges, jellyfish, molluscs, starfish, urchins, worms, crabs, prawns and fish were uncovered during the expedition. Over a dozen new species of hermit crabs, prawns, lobsters and crabs were discovered, and over 40 species of various kinds are new records for Indonesia.

Among the deep-sea creatures new to science is a crab that has fuzzy spines and blood-red eyes; a lobster with long arms and zebra-patterned shell; and a hermit crab with green eyes and orange banded pincers. …

63 stations sampled within a fortnight

The research team departed Muara Baru, Jakarta in Indonesia on 23 March 2018 on board Indonesian research vessel Baruna Jaya VIII. They sailed anti-clockwise towards Cilacap in southern Java and back, covering a total distance of 2,200 kilometres.

“14 days of shared challenges at sea has enabled us to forge strong ties with our Indonesian collaborators, and such links are important to the long-term scientific ties between our two countries,” said Prof Ng, chief scientist for the Singapore team. “On the research front, our teams have learnt a lot about how to conduct deep-sea science, handle the various equipment needed for such work, and had the opportunity to sample and examine a multitude of fantastic deep sea animals. We expect to identify more new species among the pickings of the expedition, and we certainly look forward to studying the specimens and data with our Indonesian friends.”

Prof Rahayu, chief scientist for the Indonesia team, said, “The Indonesian scientists benefitted both personally and professionally through this expedition, which was partly a capacity-building exercise for our young scientists. Through interacting with international scientists, they were exposed to new scientific techniques and methodologies in an environment that presents a different set of challenges from their own scientific specialities. Hopefully, such knowledge transfer and collaboration would build stronger and more resilient ties among between our two nations.”

About the expedition

The South Java Deep-Sea Biodiversity Expedition 2018 is the first concerted deep-sea biological exploration conducted by Singapore and Indonesia, to study deep-sea marine life in the largely unexplored part of the waters off the southern coast of West Java.

This unprecedented project is a reflection of the bold and collaborative spirit embodied in RISING50 — a celebration of 50 years of diplomatic relations between Singapore and Indonesia. This joint initiative reaffirms the depth and diversity of the long-standing collaboration between the academic and scientific communities of Singapore and Indonesia.

The samples collected will be studied by scientists from both countries. This is anticipated to take up to two years, and the results will be shared and discussed with the world at a special workshop that will be held in Indonesia in 2020. The outputs will then be collated and published in the museum’s science-citation journal, The Raffles Bulletin of Zoology.

Expedition results