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'Alien-like' Marine Life Found On Underwater Mountains Includes 100 New Species
When you digest the fact that humans know less about the seamounts dotting our planet's oceans than about the vast expanse of outer space, it might take a moment to sink in. Only a fraction of these grandiose underwater mountains have even been mapped.
The 14,500 seamounts mapped to date are projected to be a mere fraction (less than 1%) of the actual total. This staggering disparity highlights how much of our oceanic world remains unexplored.
A dormant volcano teeming with lifeThe story of the Davidson Seamount is just one example. Its name is a misnomer of sorts, as it is an underwater inactive volcano that is nestled off the Californian coast.
Discovered way back in 1933, this expansive entity covers 25 miles (40 kilometers) and has been dormant for the last 9.8 million years.
Despite the seeming desolation its description might suggest, this "dead" volcanic structure is buzzing with life.
It's home to magnificent coral reefs and extensive deep-sea octopus gardens, and offers a thriving ecosystem for marine animals including whales.
The unique biodiversity of the Davidson Seamount has made it a vital area for marine research that has focused attention on the ecological importance of these underwater mountains.
The mysteries of underwater mountainsThe Davidson Seamount, however, supports just a tiny fraction of the underwater splendors that remain unexplored.
Take a voyage to the Canadian coast where another ancient, and notably active, volcano was discovered. The site was found to be covered in millions of colossal eggs, laid by the ethereal Pacific white skates.
For comparison, the previously known nursery of this species (in the Galapagos) had a mere sprinkling of eggs, as noted by a marine biologist at Fisheries and Oceans Canada.
The most recent voyage of discovery was led by experts from the Schmidt Ocean Institute. The team unearthed a staggering 1.5-mile-high (2.4 kilometer) seamount, accompanied by three others in the southern Pacific.
One of these seamounts, situated along the Nazca ridge off the Chilean coast, offered a vision so astonishing that the explorers were left awe-struck.
They found themselves amidst a multitude of species that had never been seen by human eyes, which led them to draw parallels with a journey "through the cosmos."
Diverse marine species revealedThe month-long expedition proved highly fruitful. Unexpected residents of these depths were identified, including ghostly white sponge gardens, flying spaghetti monsters (a type of colonial hydrozoan), Casper octopuses, millennium-old glass sponges and vast forests of bamboo corals.
A fascinating fact about the glass sponges is that they build intricate, cylindrical structures using spiky "spicules" and often house crustaceans until their death.
This unique interaction between different species creates a mutual relationship, where the captivated crustaceans clean the sponges and breed within them.
Vibrant marine life on underwater mountainsThe expedition revealed a vibrant and unexpected color palette in the depths of the Chilean seamount, with numerous species displaying bright red hues.
Strange as it may seem, this coloration acts as a form of invisibility cloak in the depths where red light is absorbed first, leaving the species to appear black in the depths.
Alongside these species were cactus-like sea urchins and marine sponges that towered to human height.
A consortium of scientists from Ocean Census, who led the expedition planning, noted that this region of the southern Pacific exhibited a high level of endemic species – those that cannot be found anywhere else in the world.
Seamounts in a changing climateThe significance of seamounts extends beyond hosting unique and vibrant marine life.
According to the National Oceanic and Atmospheric Administration, seamounts are emerging as vital sanctuaries for marine life amidst the growing threats of climate change and warming oceans.
Their steep surfaces offer the right conditions for cold-water corals, sponges, and other surface-growing creatures.
The currents around these seamounts stimulate an upsurge of nutrients from the ocean floor, triggering phytoplankton growth that supports food chains within the marine world.
Additionally, these nutrient-rich areas act as hotspots for biodiversity, supporting species that are often rare or endemic to these environments.
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Environmentalist Group Sues To Gain Information About Alaska Trawler Toll On Marine Mammals
Two killer whales are seen breaching in Alaska waters on June 9, 2005. (Photo by David Ellifrit/NOAA Alaska Fisheries Science Center)
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Two killer whales are seen breaching in Alaska waters on June 9, 2005. Killer whales, also known as orcas, and other marine mammals have been killed after becoming entangled in trawl gear used in Alaska commercial fisheries. A new lawsuit accuses federal regulators of withholding important information about those incidents. (Photo by David Ellifrit/NOAA Alaska Fisheries Science Center)
The federal government has failed to give adequate information on deaths of killer whales and other marine mammals that become entangled in commercial trawling gear in Alaska waters, claims a lawsuit filed on Thursday in U.S. District Court in Anchorage.
The lawsuit, filed by the environmental group Oceana, targets the National Marine Fisheries Service, an agency of the National Oceanic and atmospheric Administration.
The whales and other marine mammals killed in fishing gear are subjects of what is known as bycatch, the unintended, incidental catch of species that are not the harvest target.
The lawsuit focuses on three Freedom of Information Act requests filed by Oceana from 2021 to 2023. Oceana asked for records, photographs and videos of animals that have been killed as bycatch in Alaska fisheries. The agency denied some requests and provided information in response to others, but that information was heavily redacted, with photographs blurred and made unrecognizable through a pixelation technique and text blacked out, the lawsuit said.
Distorted photos sent to Oceana included images of whales, Steller sea lions, a walrus, and bearded, fur and ribbon seals, according to the complaint, which seeks to compel the agency to provide more complete information.
NMFS justified the redactions and image distortions as necessary to protect confidentiality, according to the lawsuit. But Oceana, in its lawsuit, said those redactions "are not based on any valid legal requirement to protect confidential information and are not consistent" with applicable laws: the Freedom of Information Act, the Magnuson-Stevens Fishery Conservation and Management Act and the Marine Mammal Protection Act.
"Public access to information is essential to hold the government accountable and ensure U.S. Fisheries are managed sustainably," Tara Brock, Oceana's Pacific legal director and senior counsel, said in a statement issued by the organization. "The unlawful withholding of information by the Fisheries Service related to the deaths of whales, fish, and other ocean life is unacceptable. People have the right to know how commercial fisheries impact marine wildlife."
Oceana filed a related lawsuit on Thursday in the U.S. District Court of Central California over bycatch of various species of mammals and fish by the halibut trawl fishery that operates off that state's coast.
An altered photo of a killer whale that died as bycatch in Alaska trawl gear is part of the evidence presented by Oceana in a lawsuit against the National Marine Fisheries Service. The lawsuit, filed onThursday, cites this an other photos provided by NMFS as evidence that the agency is withholding important information about marine mammal deaths in the Alaska trawl fisheries. (Photo provided by Oceana)
That halibut harvest "catches enormous quantities of marine species as bycatch," which "results in the injury and death of thousands of fish and other animals," including Dungeness crab, giant sea bass, elephant seals, harbor porpoises and cormorants, among other species. That halibut fishery "has the highest bycatch rate in the nation," and it discards about 77% of the fish it catches, the lawsuit said.
The National Marine Fisheries Service declined to comment on the lawsuits filed Thursday.
The legal actions follow a period with an unusually high number of killer whales ensnared in trawl gear used to harvest Bering Sea fish. Nearly a dozen killer whales were found dead in 2023, compared to 37 cases of killer whale deaths in fishing gear that were recorded in Alaska from 1991 to 2022.
A different environmental organization, the Center for Biological Diversity, last year filed a notice of intent to sue NMFS over the trawl bycatch of whales and other marine mammals.
So far, no such lawsuit has been filed, said Cooper Freeman, the center's Alaska director. Instead, his organization has been meeting with NMFS to try to find ways to reduce the dangers to marine mammals from trawling, he said.
"At this point we have not decided to bring a lawsuit although we continue to have very, very serious concerns about the fisheries and are tracking the harms," Freeman said.
The agency has pledged some corrective action, Freeman said. It has committed to reassess harms to endangered species and it has promised to analyze Alaska's killer whales as separate populations, one in the Bering Sea and the other in the Gulf of Alaska, he said. Lumping the two populations as one can understate the impacts of bycatch deaths, he said.
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New Study Finds Marine Animals Save Energy By Swimming In A Depth 'sweet Spot'
Researchers from Swansea and Deakin Universities have found that marine animals across mammals, birds and reptiles swim at similar relative depths when travelling and not feeding to save energy.
Dr Kimberley Stokes, Professor Graeme Hays and Dr Nicole Esteban from Swansea and Deakin Universities, led research across six institutes in five countries comparing the swim depths of several sea turtle, penguin and whale species. All travelled at around three body depths from the surface in order to swim in the 'sweet spot' that minimises wave formation at the surface and vertical distance travelled.
Some semi-aquatic animals, such as mink, swim at the surface where wave generation is a major source of wasted energy. However for marine birds, mammals and reptiles travelling great distances over their lifetimes, adaptation to minimise the energetic cost of transport is expected, particularly on long journeys.
It has long been known that additional drag from wave creation minimises once a travelling object is at depths greater than three times its diameter, but it was hard to compare with travel depths of wild animals due to tracking limitations.
In this new study published in Proceedings of the National Academy of Sciences (PNAS) near surface swim depths were recorded to within 1.5 centimetres in little penguin and loggerhead turtles, along with motion data and video footage from animal borne cameras. This was compared with satellite tracking data for long-distance migrations in green turtles and data from other studies on penguins and whales. It was found that these animal swim at optimal depths predicted from physics when either 'commuting' to a foraging patch in the wild or migrating over longer distances while not feeding.
Swansea University's Dr Kimberley Stokes, lead author of the study said:
"There are of course examples where animal swim depth is driven by other factors, such as searching for prey, but it was exciting to find that all published examples of non-foraging air-breathing marine animals followed the predicted pattern. This has rarely been recorded because of the difficulty in retrieving depth data from animals that migrate over large distances, so it was great to find enough examples to show a common relationship between swim depth and body size from animals across the size spectrum from 30 cm to about 20 m in length."
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