Blue Planet II, new David Atteborough wildlife series


This video says about itself:

Blue Planet II Trailer 2 – BBC Earth

20 October 2017

In 2001, The Blue Planet opened our eyes to the worlds beneath the waves. A generation on, new science and technology allow us to journey deeper than ever before at the most crucial time in our ocean’s history. This is Blue Planet II. Take a deep breath.

Blue Planet II is narrated by Sir David Attenborough and features an original score by legendary composer Hans Zimmer. The series is set for UK broadcast on BBC One on October 29th and coming soon to BBC America in 2018. A BBC Studios Natural History Unit production, co-produced with BBC America, Tencent, WDR, France Télévisions and CCTV9. A BBC Open University Partnership.

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New butterflyfish discovery in the Philippines


Roa rumsfeldi, Credit: © 2017 Luiz Rocha and the California Academy of Sciences

From the California Academy of Sciences in the USA:

Surprise new butterflyfish from the Philippine ‘twilight zone’

October 19, 2017

A newly described species of brown-and-white Philippine butterflyfish — the charismatic Roa rumsfeldi — made a fantastic, 7,000-mile journey before surprising scientists with its unknown status. Live specimens collected from 360 feet beneath the ocean’s surface in the Philippine’s Verde Island Passage escaped special notice until a single black fin spine tipped off aquarium biologists back in San Francisco. Deep-diving researchers from the California Academy of Sciences’ Hope for Reefs team — with genetic sequencing help from a parent-son team — share their discovery of a fifth species of Roa this week in ZooKeys.

“We named this reef fish Roa rumsfeldi because, as

former United States Secretary of ‘Defence’ War, torture enabler and Iraqi archaeological treasures looting enabler

Donald Rumsfeld once said, some things are truly ‘unknown unknowns‘”, says senior author Dr. Luiz Rocha, Academy curator of ichthyology and co-leader of its Hope for Reefs initiative to research, explore, and sustain global reefs. “This fish caught us completely off-guard. After traveling from the deep reefs of the Philippines to our aquarium in San Francisco, former Academy aquarium biologist and co-author Matt Wandell noticed a black fin spine that looked different from other known Roa we’ve collected in the past. It was a light bulb moment for all of us.”

Butterflyfish — which sport bold patterns — are iconic coral reef species. Because this group’s taxonomy is relatively well understood, scientists didn’t expect to find an unknown species on a recent expedition.

Under pressure

Roa rumsfeldi and its close relatives are only know to live in mesophotic “twilight zone” reefs — a place where sunlight is scarce and divers with traditional scuba gear cannot safely visit. In the narrow band between the light-filled shallow reefs and the pitch-black deep sea, these little-known mesophotic reefs, located 200 to 500 feet beneath the ocean’s surface, are home to fascinatingly diverse and previously-unknown marine life. As part of its Hope for Reefs initiative, specially trained Academy scientists are exploring these relatively unknown frontiers with the help of high-tech equipment like closed-circuit rebreathers, which take extensive training and allow them to extend their research time underwater.

As part of their expedition-driven research, Rocha and his Academy colleagues sometimes collect live fish they believe to be unknown species in order to study their behavior (making for more robust research) and inspire the public to connect with beautiful and unique reef life during aquarium visits.

“Our human bodies are not really compressible,” says Bart Shepherd, Director of Steinhart Aquarium and co-leader of the Academy’s Hope for Reefs initiative, “but fish have swim bladders for buoyancy that can’t make the journey from twilight zone depths to the surface. We gently moved this Roa to a special lightweight decompression chamber designed just for fish, brought it to the surface, and attentively cared for it through the flight back to San Francisco and into our aquarium.”

A family affair

“The team effort between our museum’s scientists and aquarium biologists helped add a new fish to the tree of life,” says Rocha, adding that the collaboration isn’t the only reason this fish discovery feels particularly special. “My teenage son Gabriel helped sequence its genes during a summer internship — his mother and I helped show him how to use complicated genomic processes to take a closer look at the fish’s DNA. This is part of how we prove a species is distinct, and it’s always a pleasure to share that learning with young people.”

Gabriel Rocha, a high school sophomore at the time, helped sequence the mitochondrial DNA cytochrome oxidase I gene, also known as the “barcode” gene. The process from DNA extraction to amplification and sequencing takes just a few days — an ideal project for short, in-depth internships. After the sequence is obtained, the work moves from the lab to the virtual world: Major online databases contain thousands of sequences of this gene for known species, and are a great comparison tool.

New discoveries and Hope for Reefs

Considered the “rainforests of the sea,” coral reefs are some of the most biologically diverse, economically valuable, beautiful, and threatened ecosystems on Earth. They cover less than 0.1% of the ocean but contain more than 30% of marine species. Coral reefs provide critical habitat to vast marine communities — from the tiny coral polyps that make up the reef’s foundation to the colorful fishes and sharks that live among them. Coral reefs are integral to the livelihoods and well-being of hundreds of millions of people worldwide, providing protection from erosion and generating income through ecotourism and fishing.

In response to coral reef threats, the Academy launched the Hope for Reefs initiative in 2016 to explore, explain, and sustain the world’s coral reefs by making fundamental breakthroughs in coral reef biology; developing new conservation solutions and restoration techniques with partners like SECORE International and The Nature Conservancy; and sharing what we know through innovative exhibits and educational programs.

Every Academy expedition yields new understanding and surprising discoveries, and the public can see new and rare species, many of which have never been displayed in a public aquarium, at Steinhart Aquarium. Explore the great unknown alongside our scientists as they uncover the secrets of our world’s critically important reefs. Visitors to the Academy’s aquarium can take a closer look at many mesophotic marine creatures from around the world — and discover why they deserve protection — in Twilight Zone: Deep Reefs Revealed.

Alligators eat sharks, new research


This New Scientist video from the USA says about itself:

25 September 2017

A previously overlooked conflict between alligators and sharks has been going on for centuries at least, and it seems the alligators are winning. Read more here.

From Kansas State University in the USA:

Bite on this: Alligators actually eat sharks

October 16, 2017

Jaws, beware! Alligators may be coming for you. A new study documents American alligators on the Atlantic and Gulf coasts are eating small sharks and stingrays. This is the first scientific documentation of a widespread interaction between the two predators.

Jaws, beware! Alligators may be coming for you, according to a Kansas State University researcher.

While the sharks may not actually be as big as the fictional Jaws, James Nifong, postdoctoral researcher with the Kansas Cooperative Fish and Wildlife Research Unit at Kansas State University, and Russell Lowers, wildlife biologist with Integrated Mission Support Services at Kennedy Space Center, published a study in Southeastern Naturalist documenting that American alligators on the Atlantic and Gulf coasts are eating small sharks and stingrays. This is the first scientific documentation of a widespread interaction between the two predators.

“In the article, we documented alligators consuming four new species of sharks and one species of stingray,” Nifong said. “Before this, there have only been a few observations from an island off the Georgia coast, but the new findings document the occurrence of these interactions from the Atlantic coast of Georgia around the Florida peninsula to the Gulf Coast and Florida panhandle.”

Despite the freshwater and saltwater differences, Nifong said it is fairly common for sharks and rays to share the water with alligators. Many sharks and rays can swim into freshwater where opportunistic alligators can’t pass up a good meal. Although alligators don’t have salt glands like true crocodiles, they are resourceful as they travel between freshwater and marine habitats.

“Alligators seek out fresh water in high-salinity environments,” Nifong said. “When it rains really hard, they can actually sip fresh water off the surface of the salt water. That can prolong the time they can stay in a saltwater environment.”

An alligator’s diet typically consists of crustaceans, snails and fish, but because alligators are opportunistic predators, Nifong said sharks may end up on the menu.

“The findings bring into question how important sharks and rays are to the alligator diet as well as the fatality of some the juvenile sharks when we think about population management of endangered species,” Nifong said.

As part of Nifong’s dissertation research, he pumped the stomachs of more than 500 live and alert alligators to learn more about their diet. Researchers also equipped the alligators with GPS transmitters to watch their movements and found that alligators travel between freshwater sources and estuaries, which are a partially enclosed coastal water body where freshwater and salt water mix and house shark nurseries.

“The frequency of one predator eating the other is really about size dynamic,” Nifong said “If a small shark swims by an alligator and the alligator feels like it can take the shark down, it will, but we also reviewed some old stories about larger sharks eating smaller alligators.”

Nifong dug into history and found news reports from the late 1800s that described battles of large masses of sharks and alligators after flooding and high tides washed the predators together. One particular historical incident included in the journal article described how the sharks were attracted to blood from alligators feeding on fish. When the alligators were washed out to sea, the sharks attacked.

Nifong conducted the alligator diet research as part of larger research of freshwater river systems and food web dynamics. He currently is researching the drivers of native fish biodiversity in the Neosho River Basin for Martha Matter in the Kansas Cooperative Fish and Wildlife Research Unit, a part of the Division of Biology at Kansas State University.

‘Nemo’ fish threatened by global warming


This video is about orange-fin clownfish, aka orange-fin anemonefish.

Ocellaris clownfish became famous by the film Finding Nemo.

However, this species, and its clownfish (or anemonefish) relatives are now threatened by global warming. Though the fish themselves can stand warmer ocean water, the sea anemones on which they depend cannot.

As shown by research about orange-fin anemonefish (Amphiprion chrysopterus) in Moorea, French Polynesia; from Nature:

Cascading effects of thermally-induced anemone bleaching on associated anemonefish hormonal stress response and reproduction

10 October 2017

Abstract

Organisms can behaviorally, physiologically, and morphologically adjust to environmental variation via integrative hormonal mechanisms, ultimately allowing animals to cope with environmental change. The stress response to environmental and social changes commonly promotes survival at the expense of reproduction. However, despite climate change impacts on population declines and diversity loss, few studies have attributed hormonal stress responses, or their regulatory effects, to climate change in the wild. Here, we report hormonal and fitness responses of individual wild fish to a recent large-scale sea warming event that caused widespread bleaching on coral reefs.

This 14-month monitoring study shows a strong correlation between anemone bleaching (zooxanthellae loss), anemonefish stress response, and reproductive hormones that decreased fecundity by 73%. These findings suggest that hormone stress responses play a crucial role in changes to population demography following climate change and plasticity in hormonal responsiveness may be a key mechanism enabling individual acclimation to climate change.

Thornback ray reintroduction in Dutch Zeeland


This video is called Thornback ray or thornback skate (Raja clavata).

Dutch daily Trouw reports today about thornback ray reintroduction in Dutch Zeeland province.

On Saturday 14 October 2017, five young thornback rays, raised in aquariums, will be brought to an oyster farm in Yerseke town. There, they will get used to the Oosterschelde estuary water. In a few weeks’ time, they will be freed. Later, more, up to 1000, young thornback rays will be freed. It is hoped that they will be a sustainable thornback ray population in the Oosterschelde; where they had become extinct. This species is sexually mature after eight years. Will they survive now? We don’t know yet.

Male Mexican fish prefer orange females


This video says about itself:

Valley of Silence: A refuge for Mexcalpique. Ocoyoacac, State of Mexico, Mexico

2 October 2017

The Valley of Silence is located at the national park Miguel Hidalgo and Costilla, better known as La Marquesa, in the municipality of Ocoyoacac, State of Mexico; Mexico. La Marquesa is located in the Central Plateau of Mexico, one of the largest mountain systems in the world that is considered by the Word Conservation Monitoring Center as one of the most important regions in the world for the conservation of fish freshwater as the main freshwater wetlands in the country with a unique fish diversity (Domínguez- Domínguez and Pérez-Ponce de León, 2007), in which goodeids are one of the most representative groups (Domínguez-Domínguez et al., 2006).

From ScienceDaily:

Do male fish prefer them big and colorful?

Male Mexican fish are attracted to females with large bellies

October 10, 2017

Male black-finned goodeid or mexcalpique fish know what they want when they pick a female to mate with; they prefer them big-bellied and as orange as possible. Interestingly, females displaying these traits are the ones most able to produce more offspring that survive, two researchers from the National Autonomous University of Mexico have found. The study by Marcela Méndez-Janovitz and Constantino Macías Garcia is published in Springer’s journal Behavioral Ecology and Sociobiology.

The black-finned goodeid (Girardinichthys viviparus) from Mexico is a very promiscuous species of fish, with males constantly seeking a suitable partner to mate with. The females are only sexually receptive for a few days every two months after giving birth. The black-finned goodeid is viviparous, meaning that young fish fully develop inside the female’s body before they are born.

During courtship, males concentrate all their attention on only one female at a time. The wooing process is made even harder because females can be quite selective. Courtship consists of three basic elements, and is initiated when the male approaches the female he has chosen. His interest is signalled through his dorsal and anal fins standing erect. He then folds these fins over the female’s body, in a type of embrace, before starting to swim in synchrony with her. The male will go on to occasionally attempt to grip the female more firmly and to copulate.

Méndez-Janovitz and Macías Garcia wanted to find out how male black-finned goodeid decide which female to single out for their attention. Ten males were held separately under laboratory conditions. Each one was presented with two pregnant females at a time for fifteen minutes. The females were photographed to catalogue their size, colouration and belly size. The researchers took specific note of how swollen the females’ bellies were, as an indication of the number of offspring that they could be carrying.

Some of the females were visited for more than five minutes at a time and the time males spent with a female went hand in hand with the specific physical traits that she possessed. Males lingered longer with the wider bellied, and more orange-looking females. They also made more displays with their fins erect towards ones that possessed such traits. In a further experiment, it was found that the larger females were the ones who produced more offspring that ultimately could survive better. Colour did not play a role in this.

“Belly area had the largest and most positive influence on male behaviour,” explains Méndez-Janovitz. “Males made longer visits and performed more courtship displays to the females with wider bellies, while spending less time with thin-bellied females. They also made a greater effort to court females with bodies of a more orange hue.”

“Some attributes of the females are therefore linked to their reproductive value, and seem to influence how much time and effort males devote to court them,” adds Macías Garcia.

Hammerhead shark swimming, new research


This 2013 video is called Bonnethead sharks in slow motion.

From Florida Atlantic University in the USA:

Size doesn’t matter, at least for hammerheads and swimming performance

October 10, 2017

Different head shapes and different body sizes of hammerhead sharks should result in differences in their swimming performance right? Researchers have conducted the first study to examine the whole body shape and swimming kinematics of two closely related yet very different hammerhead sharks, with some unexpected results.

Sharks come in all shapes and sizes and perhaps the most unusual is the hammerhead shark, easily recognized by its oddly shaped head. Most research on hammerheads has focused specifically on their laterally expanded heads, or cephalofoil, and how they use it to see and smell as well as its effects on hydrodynamics and sensory efficiency. There are about nine known species of hammerhead sharks with dramatic differences in their body shape including the shape and size of their heads. While much is known about the variations in their electroreception, olfaction and vision, very little is known about whether or not their shape differences affect their swimming performance.

Researchers from Florida Atlantic University have conducted the first study to examine the whole body shape and swimming kinematics of two closely related yet very different hammerhead species: the Bonnethead and the Scalloped hammerhead, with some unexpected results.

Adult Bonnetheads are about 2 to 3 feet long and their head width makes up about 18 percent of their body length; adult Scalloped hammerheads are closer to 12 feet long and their head width makes up about 30 percent of their body length. Despite these differences, results of this new study, featured on the cover of the current issue of the Journal of Experimental Biology, find that in the end, size or shape really doesn’t matter, at least when it comes to swimming.

Using an interdisciplinary approach in the Biomechanics Laboratory in FAU’s Charles E. Schmidt College of Science under the direction of Marianne E. Porter, Ph.D., assistant professor of biological sciences and co-author of the study, the researchers set out to test their hypothesis. Different head shapes and different body sizes of hammerhead sharks should result in differences in their swimming performance.

Prior to starting the study, Porter, Sarah L. Hoffmann, lead author and a Ph.D. student of biological sciences, and Steven Matthew Warren, co-author and a senior in the Department of Mechanical and Ocean Engineering in FAU’s College of Engineering and Computer Science, reviewed CT scans of both species of hammerhead sharks. Because sharks are made up entirely of cartilage that is heavily mineralized, they were able see the marked differences in the two species of the sharks’ physiology from these scans.

To test their hypothesis, they focused on undulation, which is how a shark moves its body and tail from side-to-side to propel itself forward. The goal: to figure out if the movement of the body changes between these two species with very different head shapes.

Beginning in 2015, they viewed hours of video of Scalloped hammerheads and Bonnetheads swimming. They looked at tail beat frequency and tail beat amplitude. They analyzed video sequentially to select clips in which sharks completed at least three full tail beat cycles of straight, steady swimming. Warren analyzed and then condensed the videos into a minute-long segment to enable the research team to use the measurements to compare swimming mechanics between the two species. They were able to get all of the measurements they needed from that condensed one minute of video footage.

“One of the more unique aspects of our study is that we were able to observe these sharks swimming in large tanks moving around naturally,” said Porter. “Most studies place sharks in flumes, which are basically underwater treadmills that force them to move. We are interested in learning how these animals move in and of themselves for both conservation efforts and real world applications such as bioinspired engineering.”

Results of the study revealed that the Bonnetheads swing their bodies further in and out and therefore have a larger amplitude of undulation. On the other hand, Scalloped hammerheads bend faster and have a higher frequency of undulation.

“When we corrected for their body size, we discovered that they actually swam at the same speed to get to points A and B, but did so in different ways,” said Hoffmann. “Even though they are different, they get to the same destination at the same time; they’re just using different body mechanics.”

A key finding from their study is that in both species the head is moving at a different rate than the rest of the body. In fact, it is actually moving back and forth a lot faster than the rest of the body. Similar to sturgeons, a species of fish, the researchers discovered that these hammerheads have a double oscillating system. They speculate that it is because of an increased ability for sensory perception.

“There is no way that we could have anticipated the double oscillation system in this species,” said Hoffmann. “The head movement being different than the rest of the body movement is something that’s almost impossible to see with the naked eye.”

The researchers point out that with the double oscillation system, the shark’s head is moving at a much quicker rate than the rest of their body essentially to scan more of the substrate of their environment.

“Think of it like a metal detector as you move it back and forth,” said Hoffmann. “They’re going to be covering more territory for electroreception and olfaction and they need to be able to do that at a greater rate than the rest of their body.”