Coral discovery in Great Barrier Reef

This 25 October 2020 video says about itself:

Join RV Falkor as we conduct ROV SuBastian’s 401st dive on a newly discovered 500 m tall reef.

This is the ninth dive of the ‘Northern Depths of the Great Barrier Reef’ expedition.

Today we are exploring this 500 m tall ‘detached’ reef, one of seven other detached reefs offshore of Cape York Peninsula, which lie upon a ~500 m deep ledge extending out from below the Great Barrier Reef shelf. The dive will cross the broader base, then climb the steep flanks of the reef to the summit at about 50 m depth – an underwater mountain climb to find out what is living on this newly discovered reef.

From the Schmidt Ocean Institute:

Scientists have discovered a massive detached coral reef in the Great Barrier Reef — the first to be discovered in over 120 years, Schmidt Ocean Institute announced. Measuring more than 500 meters high — taller than the Empire State Building, the Sydney Tower and the Petronas Twin Towers — the reef was discovered by Australian scientists aboard Schmidt Ocean Institute’s research vessel Falkor, currently on a 12-month exploration of the ocean surrounding Australia.

The reef was first found on Oct. 20, as a team of scientists led by Dr. Robin Beaman from James Cook University was conducting underwater mapping of the northern Great Barrier Reef seafloor. The team then conducted a dive on Oct. 25 using Schmidt Ocean Institute’s underwater robot SuBastian to explore the new reef. The dive was live-streamed, with the high-resolution footage viewed for the first time and broadcast on Schmidt Ocean Institute’s website and YouTube channel.

The base of the blade-like reef is 1.5km-wide, then rises 500m to its shallowest depth of only 40m below the sea surface. This newly discovered detached reef adds to the seven other tall detached reefs in the area, mapped since the late 1800s, including the reef at Raine Island — the world’s most important green sea turtle nesting area.

“This unexpected discovery affirms that we continue to find unknown structures and new species in our Ocean,” said Wendy Schmidt, co-founder of Schmidt Ocean Institute. “The state of our knowledge about what’s in the Ocean has long been so limited. Thanks to new technologies that work as our eyes, ears and hands in the deep ocean, we have the capacity to explore like never before. New oceanscapes are opening to us, revealing the ecosystems and diverse life forms that share the planet with us.”

“We are surprised and elated by what we have found,” said Dr. Beaman. “To not only 3D map the reef in detail, but also visually see this discovery with SuBastian is incredible. This has only been made possible by the commitment of Schmidt Ocean Institute to grant ship time to Australia’s scientists.”

The discovery of this new coral reef adds to a year of underwater discoveries by Schmidt Ocean Institute. In April, scientists discovered the longest recorded sea creature — a 45m siphonophore in Ningaloo Canyon, plus up to 30 new species. In August, scientists discovered five undescribed species of black coral and sponges and recorded Australia’s first observation of rare scorpionfish in the Coral Sea and Great Barrier Reef Marine Parks. And the year started with the discovery in February of deep sea coral gardens and graveyards in Bremer Canyon Marine Park.

“To find a new half-a-kilometer tall reef in the offshore Cape York area of the well-recognized Great Barrier Reef shows how mysterious the world is just beyond our coastline,” said Dr. Jyotika Virmani, executive director of Schmidt Ocean Institute. “This powerful combination of mapping data and underwater imagery will be used to understand this new reef and its role within the incredible Great Barrier Reef World Heritage Area.”

The Northern depths of the Great Barrier Reef voyage will continue until Nov. 17 as part of Schmidt Ocean Institute’s broader year-long Australia campaign. The maps created will be available through AusSeabed, a national Australian seabed mapping program, and will also contribute to the Nippon Foundation GEBCO Seabed 2030 Project.

Elkhorn coral fights for survival

This 2016 video says about itself:

9 Colonies of Elkhorn Coral (Acropora palmata). Study by ARC Reef (Atlantic Reef Conservation) searches for a more viable method of propagating hardy variations of this endangered coral. Increasing survival rates against multiple stressors may help to save this species.

From the University of Miami Rosenstiel School of Marine & Atmospheric Science in the USA:

Elkhorn coral actively fighting off diseases on reef

Findings showed coral has core immune response regardless of disease type

October 23, 2020

As the world enters a next wave of the ongoing COVID-19 pandemic, we are aware now more than ever of the importance of a healthy immune system to protect ourselves from disease. This is not only true for humans but corals too, which are in an ongoing battle to ward off deadly diseases spreading on a reef.

A new study led by researchers at the University of Miami (UM) Rosenstiel School of Marine and Atmospheric Science looked at the immune system of elkhorn coral (Acropora palmata), an important reef-building coral in the Caribbean, to better understand its response to diseases such as white band disease and rapid tissue loss.

In the experiment, healthy corals were grafted to diseased ones. After one week, the corals were analyzed to study the coral’s overall gene expression in response to disease, if they exhibited an immune response, and whether there were different signatures of gene expression for corals that didn’t show signs of disease transmission. The researchers found that A. palmata has a core immune response to disease regardless of the type of disease, indicating that this particular coral species mounts an immune response to disease exposure despite differences in the disease type and virulence.

“Our results show that elkhorn coral is not immunocompromised but instead is actually actively trying to fight off disease,” said Nikki Traylor-Knowles, an assistant professor of marine biology and ecology at the UM Rosenstiel School and senior author of the study. “This gives me hope that the corals are fighting back with their immune system.”

Based upon these findings, the researchers suggest that corals that did not get disease may have tougher epithelia, a protective layer of cells covering external surfaces of their body. And, that the symbiotic dinoflagellate, Symbiodiniaceae, that live inside corals did not have differences in gene expression in response to disease, but over the course of the two-year study did develop differences.

Coral disease is considered one of the major causes of coral mortality and disease outbreaks are expected to increase in frequency and severity due to climate change and other human-made stressors. The Caribbean branching coral Acropora palmata which has already seen an 80 percent decrease on reefs primarily due to disease, which has resulted in them being classified as threatened under the US Endangered Species Act.

“These corals are keystone species for Florida reefs, so understanding that their immune systems are active is an important component that can be useful for protecting reefs,” said Traylor-Knowles.

Coral reef decline in Hong Kong

This 2015 video is called Hong Kong coral reef thrives despite pollution.

From The University of Hong Kong:

Was Hong Kong once a coral reef paradise?

October 15, 2020

Researchers from The University of Hong Kong’s School of Biological Sciences and The Swire Institute of Marine Science, have for the first time investigated the historical presence of coral communities in the Greater Bay Area, revealing a catastrophic range collapse and loss of diversity that occurred in the last several decades.

The research, published in the journal Science Advances, looks at fossil corals collected from over 11 sites around Hong Kong, and creates the first palaeoecological baseline for coral communities in the Greater Bay Area. Led by PhD candidate and National Geographic Explorer Jonathan CYBULSKI, the team revealed what coral genera were present in the past well before major human impacts, and these include: Acropora, Montipora, Turbinaria, Psammacora, Pavona, Hydnophora, Porites, Platygyra, Goniopora and Faviids.

Every fossil tells a story

“The data we collect helps us to create a sort of fossil time machine,” said Cybulski. “As corals grow naturally, parts of them will break off and fall to seafloor becoming a part of the sediment. Over time, many different layers of these coral skeletons will stack on top of one another. With a bit of effort we can core through the sediments and collect the different layers and reveal what coral communities were like through time,” Cybulski explained. By using this method, the team was able to collect skeletons from over 5,000 years ago, which they determined thanks to radiocarbon dating by collaborator Dr Yusuke YOKOYAMA of the Atmosphere and Ocean Research Institute at The University of Tokyo.

When the team compared their fossil data to a modern-day dataset collected by collaborators at Baptist University — Dr Jian Wen QIU and Dr James XIE, several striking conclusions were revealed. First, there has been about a 40% decrease in the number of different corals living in Southern Hong Kong waters. Second, the greatest loss was of the ecologically important yet highly-sensitive staghorn corals (Acropora), which now only lives in an area about 50% smaller than its historic range. Finally, the greatest impact and losses of corals occurred in waters that are closest to the Pearl River Estuary in the southwest and Tolo Harbor in the Northeast. Based on the data, the teams best guess for the timing of this coral community change is conservatively within the last century, but likely within the past few decades. The overall conclusion: poor water quality driven by increased development and lack of proper treatment is presently the regions greatest threat to the survival of corals.

More hope for corals

“This trend we saw of a diversity decline and the loss of Acropora is consistent with other research in different areas of the world,” Cybulski continues: “It’s particularly bad news for this region, as Acropora represents the only type of coral that is complex, and creates physical space that promotes greater biodiversity. The loss of this coral is similar to losing all the big trees in a forest.” However, similar to trees in a forest, Cybulski continued by saying there is hope for Hong Kong’s corals through conservation efforts.

Indeed, this historical research has already played a critical role in protecting and restoring corals locally. In July earlier this year, PhD Candidate Ms Vriko YU, also of the Baker Lab at HKU, pioneered a coral restoration project in Hoi Ha Wan Marine Park (Note 1). This project aims to restore and better understand what it will take to save Hong Kong corals, and was made possible due to the water quality improvements in the bay by the local government.

Using Cybulski’s historical data to infer the appropriate steps needed, the team is now returning corals such as Acropora that previously thrived in Hoi Ha, back to their proper home. To date, 100% of the reintroduced coral have survived. Furthermore, the team has documented several coral-associated invertebrates at the site, showing that this restored habitat is indeed increasing biodiversity. The team feels this multi-faceted model — historical research that identifies major stress targets for local improvements — can be used by other researchers who hope to give corals their greatest chance for future survival.

New Great Barrier Reef coral species discovered

This video is called Great Barrier Reef [National Geographic Documentary HD 2017].

From the Schmidt Ocean Institute:

New corals discovered in deep-sea study of Great Barrier Reef Marine Park

September 9, 2020

For the first time, scientists have viewed the deepest regions of the Great Barrier Reef Marine Park, discovered five undescribed species consisting of black corals and sponges, and recorded Australia’s first observation of an extremely rare fish. They also took critical habitat samples that will lead to a greater understanding of the spatial relationships between seabed features and the animals found in the Coral Sea.

The complex and scientifically challenging research was completed aboard Schmidt Ocean Institute’s research vessel Falkor, on its fourth expedition of the year, as part of the Institute’s Australia campaign. Using a remotely operated underwater robot to view high-resolution video of the bottom of the ocean floor, some 1,820 meters deep, the science team examined deep-sea bathymetry, wildlife, and ecosystems. The collaborative mission brought together scientists from Geoscience Australia, James Cook University, University of Sydney, Japan Agency for Marine-Earth Science and Technology (JAMSTEC), Queensland Museum Network, and Queensland University of Technology, to answer a range of questions about the geological evolution and biology of the deep-sea canyons and reefs.

“This included the most comprehensive midwater robotic dive survey series to ever have been conducted in the South Pacific,” said Dr. Brendan Brooke, the expedition’s lead scientist from Geoscience Australia. “Research vessel Falkor has integrated a range of technologies that have allowed us to work across the full range of ocean depths in the Coral Sea and to provide data for multiple disciplines including geology, biology, and oceanography.”

During the expedition, researchers took the deepest samples ever collected of soft coral and scleractinian coral in the Coral Sea. They also collected the first sample of ancient bedrock beneath the Great Barrier Reef, estimated to be between 40 and 50 million years old. Scientists made the first recorded observation in Australia of the extremely rare fish Rhinopias agroliba, a colorful and well-camouflaged ambush predator in the scorpionfish family. The cruise also included the most comprehensive survey of midwater jellyfish in the South Pacific.

In addition to the underwater dives, high-resolution mapping of the seafloor was conducted and covered 38,395 square kilometers, an area three times greater than Sydney. The maps include all the major coral atolls on the Queensland Plateau within the Coral Sea Marine Park and an 80-kilometer section of canyons off the northern Great Barrier Reef Marine Park.

“These maps, samples, and images are fascinating and provide a new understanding of the geological diversity and biological wealth of a region that is already world-renowned for its natural beauty,” said Dr. Jyotika Virmani, executive director of Schmidt Ocean Institute. “The data will help marine park managers to protect these ecosystems that are so vital for our global biodiversity and human health. ”

Live streaming of the 18 underwater robotic dives via Schmidt Ocean’s channel on YouTube and 112 hours of high definition underwater video during the month-long expedition, which ended August 30, allowed the science team to share their knowledge and excitement of the voyage’s discoveries with the world. Through the livestreams, the scientists could interact directly with the public via chat and commentary.

“Schmidt Ocean Institute and the technology that it has brought to Australia is a huge enabler in better understanding our marine resources from a lens of diverse disciplines,” said Dr. Scott Nichol, one of the lead expedition scientists from Geoscience Australia. “This work brings new understanding and will keep the scientists busy for years.”

How corals spawn, new research

This November 2019 video about the Great Barrier Reef in Australia is called Witness a Massive Coral Spawning.

From Rutgers University in the USA:

Surprising coral spawning features revealed

Stony coral sperm and eggs share similar genetic functions, new study shows

August 18, 2020

When stony corals have their renowned mass spawning events, in sync with the moon’s cycle, colonies simultaneously release an underwater “cloud” of sperm and eggs for fertilization. But how do the sperm and eggs survive several hours as plankton, given threats from predators, microbes and stresses such as warming waters?

A Rutgers-led team has discovered some surprising features in coral sperm and eggs (collectively called gametes), according to a study in the journal PeerJ.

While coral eggs are large and sperm cells are tiny and far more numerous, the scientists showed for the first time that eggs and sperm appear to be surprisingly similar when it comes to the gene functions they express during the planktonic stage. Proteins encoded by genes, in a process called gene expression, play many critical roles and perform most of the work in cells.

The scientists also identified two genes that may be involved in how coral sperm and eggs recognize each other in dynamic ocean waters, allowing fertilization.

“Much more attention needs to be paid to coral gametes because both egg and sperm are vulnerable to climate change and other insults,” said senior author Debashish Bhattacharya, a distinguished professor in the Department of Biochemistry and Microbiology in the School of Environmental and Biological Sciences at Rutgers University-New Brunswick. “It goes without saying that without robust sperm and egg, the coral reproductive cycle will be significantly weakened. Therefore, we need to understand in more detail how natural selection has acted on coral gametes to ensure their survival, leading to successful fertilization.”

Coral reefs protect coastlines from erosion and storms; serve as habitat, nursery and spawning grounds for fish; and provide food for about 500 million people as well as their livelihoods, according to the National Oceanic and Atmospheric Administration. But corals are threatened by global climate change that warms the ocean and leads to coral bleaching, disease, sea-level rise and ocean acidification. Other threats include unsustainable fishing, land-based pollution, tropical storms, damage from vessels, marine debris and invasive species.

By analyzing the genes of the Hawaiian stony coral Montipora capitata, the scientists revealed a blueprint for how coral eggs and sperm function. The next steps include further analyses of coral genomes to identify the substances they produce to ensure their survival and fertilization. The scientists are also interested in investigating coral species that don’t release sperm and eggs into the water before fertilization and comparing the results to the stony coral study.

“Our results pave the way for future genetic investigations, particularly in the context of climate change influences on the marine environment,” Bhattacharya said.

Coral and sturgeons, video

This video says about itself:

Next on Blue World, Jonathan visits an underwater farm where they grow coral! …All of this today on Jonathan Bird’s Blue World!

Discovery of a genetic #sex marker in #sturgeon https://t.co/01bwQdvgk0

— Phys.org Biology (@physorg_biology) November 24, 2020

Studying coral with microscopes, new method

This July 2016 video says about itself:

A new microscope mimics the human eye to study the intimate lives of coral

A new microscope gives unprecedented access to the lives of coral, from feeding to kissing, on the ocean floor.

Video Editor: Leigh Anne Tiffany

Video provided by: Jaffe Lab for Underwater Imaging, Scripps Institution for Oceanography at UC San Diego

Music: Blue Dot Sessions via Creative Commons

From the Marine Biological Laboratory in the USA:

Microscope allows gentle, continuous imaging of light-sensitive corals

June 30, 2020

Summary: Many corals are sensitive to bright light, so capturing their dynamics with traditional microscopes is a challenge. To work around their photosensitivity, researchers developed a custom light-sheet microscope (the L-SPI) that allows gentle, non-invasive observation of corals and their polyps in detail over eight continuous hours, at high resolution.

Corals are “part animal, part plant, and part rock — and difficult to figure out, despite being studied for centuries,” says Philippe Laissue of University of Essex, a Whitman Scientist at the Marine Biological Laboratory. Many corals are sensitive to bright light, so capturing their dynamics with traditional microscopes is a challenge.

To work around their photosensitivity, Laissue developed a custom light-sheet microscope (the L-SPI) that allows gentle, non-invasive observation of corals and their polyps in detail over eight continuous hours, at high resolution. He and his colleagues, including MBL Associate Scientist and coral biologist Loretta Roberson, published their findings this week in Scientific Reports.

Coral reefs, made up of millions of tiny units called polyps, are extremely important ecosystems, both for marine life and for humans. They harbor thousands of marine species, providing food and economic support for hundreds of millions of people. They also protect coasts from waves and floods, and hold great potential for pharmaceutical and biotechnological discovery.

But more than half of the world’s coral reefs are in severe decline. Climate change and other human influences are gravely threatening their survival. As ocean temperatures rise, coral bleaching is afflicting reefs worldwide. In coral bleaching, corals expel their symbiotic algae and become more susceptible to death.

“The L-SPI opens a window on the interactions and relationship between the coral host, the symbiotic algae living in their tissues, and the calcium carbonate skeleton they build in real time,” Roberson says. “We can now track the fate of the algae during [coral] bleaching as well as during initiation of the symbiosis.”

Roberson is also using Laissue’s imaging technology to measure damage to corals from “bioeroders” — biological agents like algae and sponges that break down a coral’s skeleton, a problem exacerbated by ocean acidification and increasing water temperatures.

Corals discovered off Greenland

This 29 June 2020 video says about itself:

Captioned video showing and describing a new soft coral garden habitat discovered deep off the coast of Greenland.

From University College London in England:

Soft coral garden discovered in Greenland’s deep sea

June 29, 2020

A deep-sea soft coral garden habitat has been discovered in Greenlandic waters by scientists from UCL, ZSL and Greenland Institute of Natural Resources, using an innovative and low-cost deep-sea video camera built and deployed by the team.

The soft coral garden, presented in a new Frontiers in Marine Science paper, is the first habitat of this kind to have been identified and assessed in west Greenland waters.

The study has direct implications for the management of economically important deep-sea trawl fisheries, which are immediately adjacent to the habitat. The researchers hope that a 486 km2 area will be recognised as a ‘Vulnerable Marine Ecosystem’ under UN guidelines, to ensure that it is protected.

PhD researcher Stephen Long (UCL Geography and ZSL (Zoological Society London)), first author on the study, said: “The deep sea is often over-looked in terms of exploration. In fact, we have better maps of the surface of Mars, than we do of the deep sea.

“The development of a low-cost tool that can withstand deep-sea environments opens up new possibilities for our understanding and management of marine ecosystems. We’ll be working with the Greenland government and fishing industry to ensure this fragile, complex and beautiful habitat is protected.”

The soft coral garden discovered by the team exists in near-total darkness, 500m below the surface at a pressure 50 times greater than at sea-level. This delicate and diverse habitat features abundant cauliflower corals as well as feather stars, sponges, anemones, brittle stars, hydrozoans, bryozoans and other organisms.

Dr Chris Yesson (ZSL), last author on the study, said “Coral gardens are characterised by collections of one or more species (typically of non-reef forming coral), that sit on a wide range of hard and soft bottom habitats, from rock to sand, and support a diversity of fauna. There is considerable diversity among coral garden communities, which have previously been observed in areas such as northwest and southeast Iceland.”

The discovery is particularly significant given that the deep sea is the most poorly known habitat on earth, despite being the biggest and covering 65% of the planet. Until very recently, very little was known about Greenland’s deep-sea habitats, their nature, distribution and how they are impacted by human activities.

Surveying the deep sea has typically proved difficult and expensive. One major factor is that ocean pressure increases by one atmosphere (which is the average atmospheric pressure at sea level) every 10 metres of descent. Deep-sea surveys, therefore, have often only been possible using expensive remote operating vehicles and manned submersibles, like those seen in Blue Planet, which can withstand deep-sea pressure.

The UK-Greenland research team overcame this challenge by developing a low-cost towed video sled, which uses a GoPro video camera, lights and lasers in special pressure housings, mounted on a steel frame.

The lasers, which were used to add a sense of scale to the imagery, were made by combining high-powered laser pointers with DIY housings made at UCL’s Institute of Making, with help from UCL Mechanical Engineering.

The team placed the video sledge — which is about the size of a Mini Cooper — on the seafloor for roughly 15 minutes at a time and across 18 different stations. Stills were taken from the video footage, with 1,239 images extracted for further analysis.

A total of 44,035 annotations of the selected fauna were made. The most abundant were anemones (15,531) and cauliflower corals (11,633), with cauliflower corals observed at a maximum density of 9.36 corals per square metre.

Long said: “A towed video sled is not unique. However, our research is certainly the first example of a low-cost DIY video sled led being used to explore deep-sea habitats in Greenland’s 2.2million km² of sea. So far, the team has managed to reach an impressive depth of 1,500m. It has worked remarkably well and led to interest from researchers in other parts of the world.”

Dr Yesson added: “Given that the ocean is the biggest habitat on earth and the one about which we know the least, we think it is critically important to develop cheap, accessible research tools. These tools can then be used to explore, describe and crucially inform management of these deep-sea resources.”

Dr Martin Blicher (Greenland Institute of Natural Resources) said: “Greenland’s seafloor is virtually unexplored, although we know is it inhabited by more than 2000 different species together contributing to complex and diverse habitats, and to the functioning of the marine ecosystem. Despite knowing so little about these seafloor habitats, the Greenlandic economy depends on a small number of fisheries which trawl the seabed. We hope that studies like this will increase our understanding of ecological relationships, and contribute to sustainable fisheries management.”

Shipwreck Coral Reefs, video

This video says about itself:

Exploring Shipwreck Coral Reefs

Next on Blue World, Jonathan learns how to dive without a scuba tank by holding his breath a long time! But first, he investigates shipwrecks that are turning into coral reefs. All of this today on Jonathan Bird’s Blue World!

Restoring Mexican coral reefs, video

This 17 June 2020 video says about itself:

Oceanographer and National Geographic Explorer Paola Rodriguez works to restore coral reefs in her native Mexico. Once thought impossible, Paola and her team are proving that reefs can recover from even serious damage if given a chance.