Top 15 largest sharks of all time


This 19 September 2018 video says about itself:

15 Largest Sharks to Ever Exist – Comparison

This is another video on the size comparison of sharks but on this one we will showcase the 15 largest sharks to ever have existed which includes extinct giant sharks and the existing / alive sharks we have today.

Sharks have existed in the past that were way bigger than modern-day sharks and they even dwarf the great white in size. Some sharks were even as big as the modern-day basking and whale sharks.

The Meg / Megalodon has his competition by some of these species of sharks in comparison in size and ferociousness.

The 15 largest sharks include the biggest sharks from modern day and they rank way down in comparison to some sharks like the primitive Helicoprion, the ginsu shark and the Megalodon.

The primitive Otodus is one shark that can rival the lesser Megalodon specimens in size … So enjoy this video on the 15 largest sharks to ever exist – comparison.

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Much wildlife in United States Marine National Monument


This video from the USA says about itself:

An (Animated) Tour of the Northeast Canyons and Seamounts

25 October 2017

Join NRDC senior oceans scientist Lisa Suatoni on an animated submersible tour of the weird, wonderful, and imperiled underwater world of the Northeast Canyons and Seamounts National Monument. The ocean floor off the east coast of the United States is carved with canyons deeper than the Grand Canyon, and, beyond those, extinct volcanoes. President Obama made almost 5,000 miles of this unique area a national monument, but the Trump administration is interested in revoking its monument status to open this pristine area with 4,000-year-old corals to industrial fishing, mining, and drilling. Not many people get to explore these incredible depths—but once you see what’s down there, you’ll never be the same!

Take Action: here.

From the New England Aquarium in the USA:

Aerial survey reveals great diversity and abundance in NE Canyons Marine National Monument

Protected resource status of monument is under review by Trump administration

September 14, 2018

Airborne marine biologists were amazed by the sheer abundance and diversity of large marine wildlife in their recent aerial survey of the Northeast Canyons and Seamounts Marine National Monument, the only marine national monument on the East Coast, about 150 southeast of Cape Cod. Scientists with the Anderson Cabot Center for Ocean Life at the New England Aquarium documented more than 600 animal sightings in just four hours, including a “superpod” of about 250 common dolphins and a rare sighting of a giant manta ray.

The researchers, aboard a small, four-seat airplane, saw the equivalent of three animal sightings every minute. They also spotted hundreds of Risso’s dolphins, some rarely-seen beaked whales, pods of bottlenose dolphins, and the bizarre-looking giant ocean sunfish, also known as the Mola mola. The 605-total seen during the September survey nearly doubles the survey team’s previous sighting record of 339 animals in April 2018.

“This was an amazing number of animals to see in such a short period of time and the highest count we’ve seen so far in our surveys”, said Dr. Ester Quintana, head of the survey team. “The marine monument is known as the ‘Serengeti of the sea’ for a reason.”

The Northeast Canyons and Seamounts Marine National Monument is a critical hotspot of biodiversity on the edge of the continental shelf where the shallow seas off of New England drop sharply into the deep waters of the northwestern Atlantic. On September 16, the monument will celebrate its two year anniversary. In 2016, President Obama designated three underwater canyons that are deeper than the Grand Canyon, and four seamounts as tall as the Rockies, as the first American marine national monument in Atlantic waters. At the moment, is still the most strongly protected area in U.S. Atlantic waters. However, in 2017, Secretary of the Interior Ryan Zinke recommended to President Trump has recommended weakening the area’s protections.

“It’s simply impossible to overstate the uniqueness of this habitat and its value as the most protected region in the U.S. Atlantic”, said Vikki Spruill, President and CEO of the New England Aquarium. “And let’s be clear about what it protects: Us. Our way of life. Our values. Our future. The monument should be here to stay.”

Given the great distance offshore, documenting the marine life in the Northeast Canyons and Seamounts is a challenge. During the 4-hour aerial survey, the team spotted 335 common dolphins, 30 bottlenose dolphins, 2 beaked whales, 3 ocean sunfish (Mola mola), and a giant manta ray. The manta was an especially unexpected sight because the species is very rarely seen this far north. All of the dolphin groups included many calves and juveniles, reinforcing observations that the monument is a nursery area for several species.

This was the fourth in a series of aerial surveys of the monument that began in summer 2017, and the number of sightings by the scientists during this survey was higher than any other, nearly double the number of animals observed last fall.

Top 10 smallest sharks


This 14 August 2018 video says about itself:

Meet the top 10 smallest sharks in the world.

You already know the biggest sharks like the megalodon or the great white shark, but it’s time you saw these predators in their smaller version. Here is the list of the tiniest sharks that exist in the world.

Dwarf lantern shark
Cylindrical lanternshark
Pale Catshark
Smalleye pygmy shark
Panama Ghost Catshark
Pygmy ribbontail catshark
Green lanternshark
Broadnose Catshark
Pygmy shark
Spined pygmy shark

New Pacific Ocean fish discoveries


This 10 September 2017 video says about itself:

Three bizarre-looking types of deep sea creatures have been spotted in one of the deepest parts of the Pacific Ocean — the Atacama Trench, located up to 7 miles below the ocean’s surface off the coast of Peru and Chile.

A group of 40 scientists from 17 different nations teamed up to search the freezing, pitch-black area, using cameras and other equipment. With these tools, they were able to find three interesting creatures, which they believe are types of snailfish, about 5 miles deep.

From Newcastle University in England:

Three new species of fish discovered in the extreme depths of the Pacific Ocean

September 10, 2018

An exploration to one of the deepest places on earth has captured rare footage of what is believed to be three new species of the elusive Snailfish.

Involving a team of 40 scientists from 17 different nations, including Dr Alan Jamieson and Dr Thomas Linley from Newcastle University, UK, the expedition to the Atacama Trench has uncovered a wealth of information about life in one of the deepest places on earth.

Among the new discoveries are what the team believe to be three new species of snailfish.

Temporarily named ‘the pink, the blue and the purple Atacama Snailfish’, the footage shows the fish feeding and interacting in their secret world 7,500 metres below the surface.

These fish are part of the Liparidae family and do not conform to the preconceived stereotypical image of what a deep-sea fish should look like.

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. The snailfish will be featured as part of the Challenger Conference 2018 which kicks off at Newcastle University from today and runs until Friday.

Dr Thomas Linley, from Newcastle University, said:

“There is something about the snailfish (fish of the family Liparidae) that allows them to adapt to living very deep. Beyond the reach of other fish they are free of competitors and predators.

“As the footage clearly shows, there are lots of invertebrate prey down there and the snailfish are the top predator, they seem to be quite active and look very well-fed.

“Their gelatinous structure means they are perfectly adapted to living at extreme pressure and in fact the hardest structures in their bodies are the bones in their inner ear which give them balance and their teeth. Without the extreme pressure and cold to support their bodies they are extremely fragile and melt rapidly when brought to the surface.”

Amazingly, the team did manage to catch one the new species of snailfish which followed its amphipod prey into one of the traps. The single specimen was in very good condition and, following careful preservation, is currently being described by the Newcastle team with the help of colleagues from the United States and the Natural History Museum, London.

Pioneering technology for exploration of the ultra-deep

The Hadal Trenches are one of the last great frontiers in marine science and the deepest places on Earth.

Mostly located around the Pacific rim in areas where tectonic plate collide and plunge, the seafloor reaches depths close to 11,000 metres (~7 miles) in some areas.

The Atacama Trench, a trench almost 6000 km long and more than 8000 m deep, runs along the west coast of South America.

Newcastle University scientists and engineers have been pioneering technology for the exploration of these ultra-deep environments for the last five years and have to date completed nearly 250 deployments of their novel ‘lander’ systems.

Using two full-ocean depth (11,000 m) capable landers equipped with HD cameras and traps the Newcastle team assessed the animals found within the trench.

Designed and developed at Newcastle University, the lander is dropped overboard, and free-falls to the ocean floor where it carries out a variety of monitoring and sampling tasks.

It can take four hours for a trap to sink to the bottom and after waiting an additional 12 to 24 hours, the researchers send an acoustic signal to the trap, which releases weights and the lander rises to the surface with the help of floatation.

This allows the team to catch fish specimens and take video footage of life at the bottom of the ocean.

On this latest expedition to the Atacama Trench in the SE Pacific off the coast of Peru and Chile, the team deployed their baited camera system 27 times from 2537 to the deepest point, Richard’s Deep, at just over 8000 metres.

More than 100 hours of video and 11,468 photographs were taken at the seabed.

As well as the snailfish, the team also filmed some astonishingly rare footage of long-legged isopods, known as Munnopsids, which are about the size of an adult hand.

These crustaceans have small bodies, extraordinarily long legs and swim backwards and upsides down, propelling themselves with paddles on their ventral side — their ‘tummies’ — before righting themselves on the seafloor and spreading their long walking legs out like a spider.

“We don’t know what species of munnopsid these are but it’s incredible to have caught them in action in their natural habitat — especially the flip they do as they switch from swimming to walking mode”, says Dr Linley.

Clown fish, why white stripes?


This video from Australia says about itself:

Never-Before-Seen Footage of Clownfish Hatching

5 January 2018

Thanks to the use of a specialized infrared camera, we’re now able to witness a never-before-seen phase of clownfish development: the nighttime hatching of larva from their eggs.

From the Series: David Attenborough’s Great Barrier Reef: Builders.

By the CNRS in France:

Clown fish: Whence the white stripes?

September 4, 2018

Summary: Scientists have been training their attention on the developmental and evolutionary determinants of white stripes in clown fish. They now detail why, when, and how these bands arose and help elucidate their role in clown fish social organization.

Coral reef fish are known for the wide range of colors and patterns they display, but the mechanisms governing the acquisition of these characteristics are still poorly understood. These researchers focused on clown fish, a group including thirty-some species distinguished by numbers of white stripes (zero to three) and by their colors, including yellow, orange, red, and black.

The team first demonstrated that stripes are essential for individual fish to recognize others of their species. Such recognition is critical to the social organization of clown fish living among sea anemones where several species may be simultaneously present and young fish seek to establish permanent homes.

The researchers then deciphered the sequences of stripe appearance and disappearance during the life of a clown fish. Stripes appear one at a time, starting near the head and progressing towards the tail, during the transition from the larval to the juvenile stage. The team further observed that some stripes are occasionally lost between the juvenile and adult stages, this time beginning at the tail end.

In an attempt to understand the origin of these patterns, the scientists delved into the evolutionary history of clown fish. They discovered that their common ancestor sported three stripes. Just like today’s clown fish, these ancestral stripes were made up of pigmented cells called iridophores containing reflective crystals. Over the course of evolutionary history, some species of clown fish gradually lost stripes, resulting in today’s range of color patterns.

The research team would like to follow up by identifying the genes that control the acquisition of white stripes for a greater understanding of how they evolved. This should clue them in to the processes behind color diversification and the role color plays in the social organization of reef fish.

Helping Australian freshwater fish


This 2014 video is called Australian Native Pond (fish).

From the University of Queensland in Australia:

A breakthrough for Australia’s fish

September 4, 2018

A research team from the Threatened Species Recovery Hub has made a breakthrough that could help dwindling numbers of Australian freshwater fish species.

Dr Jabin Watson from the University of Queensland says the innovation will allow small and young fish to get past barriers like culverts.

“Simple things like dams, culverts and weirs can be enough to prevent fish from migrating, accessing habitat and even escaping predators“, said Dr Watson.

“These kinds of barriers are a major contributor to the declines and local extinctions of many Australian fish species.”

Native fish in the Murray Darling Basin are estimated to be at only ten per cent of pre European numbers.

“When streams pass through a culvert — the pipes under most roads — the flow is concentrated”, Dr Watson said.

“This fast flow can be impossible for many fish to navigate as they simply can’t swim that fast for that long.

“Small and young fish are particularly impacted.”

The team used a biohydrodynamics laboratory at UQ to test the swimming ability and behaviour of native fish species.

“Many different types of devices have been trialled in Australia to help fish move past barriers like culverts”, Dr Watson said.

“Baffles are frequently used, with the aim of giving fish areas to rest along the way, but our laboratory testing has shown that the turbulence created can really knock fish about and make them disorientated.

“We’ve discovered a completely new approach that has proved very successful in laboratory trials, enabling small and young fish to navigate fast flows.

“We have taken advantage of a property of fluid mechanics called the boundary layer to create a channel of slower flowing water along one side of the culvert”, he said.

“The boundary layer is a thin layer of slower water generated by a fluid moving across a solid surface, such as the bed and walls of a culvert.

“By adding a beam along the culvert wall, we have added another surface close to the culvert corner.

“The boundary layers from these three surfaces merge to create a reduced velocity channel that is large enough for small fish to swim through.

Dr Watson said no native fish species have evolved to cope with things like culverts.

“Strategies that work to improve fish passage provide hope for our freshwater species”, Dr Watson concludes.