The new captain of the Endurance shipwreck is an anemone
Huw Griffiths, a marine biogeographer with the British Antarctic Survey, was eating pancakes when news broke that the wreck of the Endurance – the famous ship helmed by Ernest Shackleton that sank during an expedition in 1915 – had been discovered.
Dr. Griffiths found himself far more interested in the pictures than his breakfast. His first thought was that the ship looked almost fake, considering how eerily pristine it has remained 106 years after sinking to the bottom of the Weddell Sea near Antarctica. His second thought: What was living on it?
Over the years, the ship had become as lush as a garden. In one Twitter feed, Dr. Griffiths zoomed in on images of the wreck to highlight the creatures he recognised: anemones, sponges, sea squirts, starfish and a lemon-yellow water lily. Other tenants were more mysterious – white tendrils, transparent spots and a mysterious feather-shaped creature.
Christopher Mah, starfish researcher at the Smithsonian National Museum of Natural History, said he expected a “rich bonanza of creatures living in and among the Endurance wreck”. In the deep sea, where food is scarce and the landscape is mostly silt, a shipwreck is valuable real estate.
The wreck provides insight into the types of life in the Weddell Sea that live on hard structures, according to Louise Allcock, a zoologist at the National University of Ireland in Galway. “There has been a lot of work in the Weddell Sea, but especially on soft bottoms,” Dr Allcock said. “There is a chance that there are new species, if only because of a lack of research,” she added.
When Katrin Linse, a marine biologist with the British Antarctic Survey, scanned the images of the wreckage in her office, she admired anemones, worms, sponges and even a bright red amphipod, possibly a species of the genus Eurythenes , which swam away from the destroy. Then she spotted something quite surprising, perched near a porthole. “There’s a crab,” Dr. Linse said. “It shouldn’t be there.”
Dr Linse, who helped discover the first hydrothermal vents in the Southern Ocean, has an eye for white crabs. Ghostly white creatures in deep sea mud may indicate the presence of nearby vents.
Dr. Linse texted Dr. Griffiths, asking why he hadn’t told her about the crab.
He had completely missed the animal, its presence in the video only a leggy white dot. A crab may be commonplace in many places, but a crab had never been spotted before in the Weddell Sea. When Dr. Linse reviewed the video, she found three more crabs.
The general absence of decapods – which include shrimp, crabs and lobsters – in Antarctica has “puzzled polar biologists for so many years”, said Paula Rodríguez Flores, a researcher who studies squat lobsters in high sea at Harvard University’s Museum of Comparative Zoology. an email.
Scientists had at one time speculated that decapod crabs were driven out of Antarctica millions of years ago and only recently returned due to climate change, so “the crabs of the ‘Antarctica are always very exciting to find,’ said Dr Linse.
Dr Griffiths wondered if the crab spotted on the wreck could be a species in the family Kiwaidae, which includes a hairy white yeti crab that lives near vents off Antarctica. But closer examination revealed the crustacean was not a crab but a stocky deep-sea lobster of the genus Munidopsis, Dr Rodríguez Flores said.
There is only one species of squat lobster recorded from Antarctic waters. “It’s definitely a different species,” she said, adding that further examination would establish its identity.
The presence of the crustacean opens up many new questions. “How did they get there?” asked Dr. Linse. “Is it a new species of Munidopsis? asked Dr. Rodríguez Flores. “Is it eating the ship?” asked Dr. Griffiths.
Although the crab is presumably free to roam around the Endurance, many of the ship’s other inhabitants are passive eaters like crinoids, glass sponges, and anemones. These creatures likely live off the sprinkling of rubbish called sea snow, which contains a lot of krill droppings here, Dr Griffiths said. The vessel’s elevation above the seabed allows these largely immobile creatures to take advantage of water currents to feed, Dr Mah said.
Although the quality of the video prevents a more precise identification of several of these species, some inhabitants stood out, especially near the ship’s wheel. Dr. Mah identified a six-armed serpentine starfish as a Brisingid, Freyastera, or Belgicella starfish. These stars extend their spiny arms into the water to capture small crustaceans and other food, he added.
Scientists are divided on whether a creature sitting near the wheel – which looks like an ostrich feather crossed with a Christmas tree – is a hydroid or black coral. Dr. Allcock is the team’s hydroid, noting that the stem didn’t look straight enough for the black coral. Joan J. Soto Àngel, a researcher at the University of Bergen in Norway, said it did not resemble known hydroids at such depths, but added that he was “100% sure there must be several species of hydroids growing on the wreck”.
The Endurance wreck is considered a historical monument under the terms of the Antarctic Treaty. “No one is allowed to touch it,” Dr Griffiths said. Still, higher-resolution videos could help scientists determine what species are living on the wreckage and whether any of them are new.
For Estefanía Rodriguez, a curator at the American Museum of Natural History in New York who studies anemones, clearer videos might not be enough for species identification. The Endurance is dotted with sprawling stems of anemones, from large white ones to thinner orange ones. But many species of anemones look alike on the outside, which means researchers have to cut them open to identify them.
“After more than 20 years of studying this group, if someone shows me a picture and asks me what it is, I can only say ‘anemone,'” Dr Rodriguez said. “It’s not because I’m useless at my job.”
With extreme caution, Dr. Rodriguez suggested that the large white anemone belongs to the family Actinostolidae and the oranges to the family Hormathiidae.
Although Dr. Rodriguez was happy to see the recovered wreckage, she was even happier to see the old ship’s hull dominated by anemones, which she says are understudied animals. “The group is about 600 million years old. That’s what fascinates me,” Dr. Rodriguez said. “How they endure: It’s hard stuff.”
For now, it’s hard to say how old the Endurance’s invertebrate crew are – how many moved in shortly after sinking 106 years ago or more recently. But glass sponges can live for thousands of years and anemones for decades.
From what is visible in the video, the largest living thing behind the wheel of the Endurance is an anemone (unidentifiable species).
“The old crew made it out alive, and here’s who moved in,” Dr Griffiths said. “Who knows where this sea anemone is taking her?