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‘Major discovery’ beneath Antarctic seas: A giant icefish breeding colony – WION

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As soon as the remotely operated camera glimpsed the bottom of the Weddell Sea, more than 1,000 feet below the icy ceiling at the surface, Lilian Boehringer, a student researcher at the Alfred Wegener Institute in Germany, saw the icefish nests. The sandy craters dimpled the seafloor, each the size of a hula hoop and less than a foot apart. Each crater held a single, stolid icefish, dark pectoral fins outspread like bat wings over a clutch of eggs.

Aptly named icefishes thrive in waters just above freezing with enormous hearts and blood that runs clear as vodka. Their blood is transparent because they lack red blood cells and hemoglobin to transport oxygen throughout the body. Icefishes’ loss of hemoglobin genes was less an evolutionary adaptation than a happy accident, one that has allowed them to absorb the oxygen-rich Antarctic waters through their skin.

The sighting occurred in February 2021 in the camera room aboard a research ship, the Polarstern, which had come to the Weddell Sea to study other things, not icefish. It was 3 a.m. near Antarctica, meaning the sun was out but most of the ship was asleep. To Boehringer’s surprise, the camera kept transmitting pictures as it moved with the ship, revealing an uninterrupted horizon of icefish nests every 20 seconds.

“It just didn’t stop,” Boehringer said. “They were everywhere.”

Half an hour later, Autun Purser, a deep-sea biologist at the same institute, joined Boehringer. On the camera feed, there remained nothing but nests.

“We were like, is this ever going to end?” Purser said. “How come no one has ever seen this before?”

The nests persisted for the entire four-hour dive, with 16,160 recorded on camera. After two more dives by the camera, the scientists estimated the colony of Neopagetopsis ionah icefish stretched across 92 square miles of the serene Antarctic sea, totaling 60 million active nests. The researchers described the site — the largest fish breeding colony ever discovered — in a paper published Thursday in the journal Current Biology.

“Holy cow,” said C.-H. Christina Cheng, an evolutionary biologist at the University of Illinois-Urbana-Champaign, who was not involved with the research. “This is really unprecedented,” she said. “It is crazy dense. It is a major discovery.”

The paper provides “evidence of a complex and so far undescribed benthic ecosystem in the Weddell Sea,” said Mario La Mesa, a biologist at the Institute of Polar Sciences in Bologna, Italy, who was not involved with the research.

“I would not be surprised to find other massive colonies of breeding fishes elsewhere,” said La Mesa, who last year described the same Antarctic icefish species’ nest-guarding behavior from sites near the newly discovered colony.

Each of the newly discovered nests held, on average, 1,735 large, yolky eggs — low fecundity for a fish. An unprotected clutch would prove an easy snack for predators like starfish, polychaete worms and sea spiders, Cheng said. So the males stand sentry to ensure their offspring are not devoured, at least not before they have the chance to hatch, and may clean the nests with their elongated lower jaw, according to Manuel Novillo, a researcher at the Bernardino Rivadavia Museum of Natural Science in Argentina, who was not involved with the research.

About three-quarters of the colony’s nests were guarded by a single fish. The others had eggs but no fish, a fish carcass furred white with bacteria or nothing at all. Near the edges of the colony, many unused or abandoned nests cradled several icefish carcasses, many with starfishes and octopuses feasting on their eyes and soft parts.

“If you die in the fish nest area, you rot there,” Purser said. “But if you die at the edges, then it seems to be everyone grabs you and starts eating you there.”

The researchers observed that the colony occupied an unusually warm patch of deep water, with temperatures up to about 35 degrees Fahrenheit — practically toasty compared to other Antarctic waters.

Although the discovery of the nests contributes to scientists’ understanding of the icefish life cycle, it raises even more questions. How often are the nests built, and are they reused? Do the fish die after the eggs hatch? Or, perhaps the most obvious: “Why there?” Cheng asked.

The authors have no sure answers, only speculations. Maybe the warm deep currents guide the fish to the grounds. Maybe there is a bounty of zooplankton for the fry to devour. Or maybe it’s something else.

But there must be something special about the location of the active colony. Around 31 miles west, the researchers found a patch of seafloor similarly littered with nests: all empty. These nests were abandoned, overtaken by sponges and corals — long-living creatures that take years to grow, Purser said.

Waters above the icefishes’ expansive settlement also host hungry, foraging Weddell seals. When the researchers collected satellite tracking data from seals during the expedition and analyzed it with historical data, they found, unsurprisingly, that the seals dive primarily to the icefish nests. “They’re having a nice dinner,” Purser said.

Before the end of the cruise, the researchers deployed a camera that will photograph the site twice daily for two years, hopefully revealing even more about the life cycle of the icefish. Novillo said he is looking forward to seeing what the camera captures. “It might constitute the first field observation of courtship behavior and/or nest preparation,” he wrote in an email.

New insights into how icefish reproduce and contribute to polar food webs could help manage and conserve populations. The authors argue the new paper provides enough evidence to protect the Weddell Sea under the Convention on the Conservation of Antarctic Marine Living Resources.

“The seafloor is not just barren and boring,” Purser said. “Such huge discoveries are still there to be made, even today in the 21st century.”

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Canadian Scientist Goes Back in Time Using the World's Biggest Space Telescope – Optic Flux

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A group of astrophysicists may soon have a key to unraveling the puzzle of life’s beginnings.

On December 25, the James Webb Space Telescope was launched into orbit from French Guiana, South America.

Webb is the biggest and most powerful space telescope ever built by NASA, the National Aeronautics and Space Administration, at the cost of $10 billion US.

Tyrone Woods, a Canadian astronomer, aims to utilize it to go through the time and uncover the earliest stars ever produced.

“We’re going to be able to look back into this earliest epoch of the universe,” Woods stated.

Woods, a Plaskett Fellow at the National Research Council of Canada’s Herzberg Astronomy and Astrophysics Research Centre in Victoria, B.C., is originally from Edmonton.

The Hubble Space Telescope was launched in 1990, and NASA claims Webb as its successor.

On December 25, Arianespace's Ariane 5 rocket launches from French Guiana, carrying NASA's James Webb Space Telescope.
On December 25, Arianespace’s Ariane 5 rocket launches from French Guiana, carrying NASA’s James Webb Space Telescope.

NASA, the European Space Agency, and the Canadian Space Agency collaborated on the new telescope.

The project has been in the works for decades.

Webb’s mirror is substantially bigger than Hubble’s, allowing it to capture more light and see farther back in time.

“Light has a fixed speed. It doesn’t travel infinitely fast. It takes time,” Woods said on CBC Edmonton’s Radio Active.

Many stars are millions, if not billions, of light-years distant from Earth, even though light travels at 300,000 kilometers per second.
Some of the stars that we see in the night sky may no longer exist.

NASA’s James Webb Space Telescope was placed on top of the Ariane 5 rocket that will send it into space from Europe’s Spaceport in French Guiana on December 11.

Stellar Nurseries

Stellar nurseries are places of dust and gas where stars are born.
Woods’ team used computer simulations to create a cosmic roadmap to aid in the search for the earliest stars.

“So conventionally, we had always thought of the first stars as being so very compact and very blue. We’ve seen that in some of them [nurseries of the very first stars], they would be the perfect conditions for making really massive, really bloated, really red stars.”

HD 140283, the Methuselah Star, is now the oldest known star.
It is thought to be 14 billion years old, around the same age as the universe.

Webb is an infrared telescope, which means it can see the light that human eyes can’t see.
Because infrared is a wavelength that our planet produces, it’s feasible that concentrating on infrared light may lead to the discovery of a planet identical to Earth.
Woods added they’ll be searching in the surroundings around some huge clusters of galaxies for a magnified light from behind them to obtain a very, really deep exposure of the early cosmos.

Aside from the origins of the stars, Woods thinks that the new telescope will aid scientists in discovering the first black hole, understanding how gases assemble in the cosmos and learning more about how our own solar system was created.

After traveling 1.5 million kilometers from Earth to its targeted orbit around the sun, Webb will spend the next several months deploying its mirrors and enormous sunshield and cooling down before seeing into the furthest regions of the cosmos.

“Over the subsequent year, we’re going to start to see the first really exciting results,” Woods added.

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Canadian scientist examines melting Antarctic glacier, potential sea level rise – Williams Lake Tribune

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As icebergs drifted by his Antarctica-bound ship, David Holland spoke this week of how the melting glacier he’s cruising towards may contain warning signals for the coasts of far-off Canada.

The atmospheric and ocean scientist from Newfoundland is part of an expedition to one of the world’s most frigid and remote spots — the Thwaites glacier in the western portion of the continent — where he’ll measure water temperatures in an undersea channel the size of Manhattan.

“The question of whether sea level will change can only be answered by looking at the planet where it matters, and that is at Thwaites,” said Holland, director of the environmental fluid dynamics laboratory at New York University, during a satellite phone interview from aboard the South Korean icebreaker Araon.

It’s over 16,000 kilometres from Holland’s hometown in Brigus, N.L., on Conception Bay, to the site about 100 kilometres inland from the “grounding zone” where the Thwaites’ glacier leaves the continent and extends over the Pacific.

The team’s 20,000 tonnes of drilling gear will be assembled to measure the temperatures, salinity and turbulence of the Pacific waters that have crept underneath and are lapping away at the guts of the glacier.

“If it (the water) is above freezing, and in salt water this means above -2 centigrade, that’s not sustainable. A glacier can’t survive that,” said Holland.

Since 2018, more than 60 scientists from the International Thwaites Glacier Collaboration group have been exploring the ocean and marine sediments, measuring warming currents flowing toward the deep ice, and examining the stretching, bending, and grinding of the glacier over the landscape below.

The Florida-sized Thwaites glacier faces the Amundsen Sea, and researchers have suggested in journal articles over the past decade it may eventually lose large amounts of ice because of deep, warm water driven into the area as the planet warms. Some media have dubbed Thwaites the “doomsday glacier” due to estimates that it could add about 65 centimetres to global sea level rise.

Holland notes current research models mainly suggest this would happen over several centuries, however there are also lower probability theories of “catastrophic collapse” occurring, where the massive ice shelf melts in the space of decades. “We want to pay attention to things that are plausible, and rapid collapse of that glacier is a possibility,” he said.

While Holland looks at the undersea melting, other scientists are examining how the land-based portions of Antarctic glaciers are losing their grip on points of attachment to the seabed, potentially causing parts to detach. Still other researchers point to the risk of initial fractures causing the ice shelf to break, much like a damaged car windshield.

All of the mechanisms must be carefully observed to prove or disprove models on the rates of melting, said Holland.

“If the (water-filled) cave beneath the glacier we’re studying gets bigger, then Antarctica is losing ice and retreating, and if the cave collapses on itself, then (the cave) will disappear. This is how Antarctica can retreat, these kinds of specific events,” he said.

The implications of the glacier work reach back to Atlantic Canada — which along with communities along the Beaufort Sea and in southwestern British Columbia is the region most vulnerable to sea level rise in the country, according to federal scientists.

Everything from how to calculate the future height of dikes at the low-lying Chignecto Isthmus — the narrow band of land that connects Nova Scotia to the rest of the country — to whether the Fraser River lowlands may face flooding is potentially affected by glacial melting in Antarctica, he said.

Scenarios where Antarctica ice melts more quickly than expected are briefly discussed in the 2019 federal report Canada’s Changing Climate. Based largely on Intergovernmental Panel on Climate Change reports that refer to them as low-probability “tipping point” theories, the 2019 report invoked the possibility of one metre of sea level rise by 2100.

However, Blair Greenan, a federal oceanographer who oversaw the relevant chapter of the report, said in a recent interview that a rise in global sea levels approaching two metres by 2100 and five metres by 2150 “cannot be ruled out” due to uncertainty over ice sheet processes like Thwaites.

“We don’t know, nobody knows,” Holland said. “But it’s plausible these things can change, and several feet of sea level change would have a major impact on Atlantic Canada. What’s needed is glacier forecasting that resembles the kinds of accuracy that weather forecasting currently provides.”

However, collecting glacier forecast data is a daunting undertaking in the short period — from late January until mid-February — when scientists can safely take readings. Helicopters will be ferrying a hot water drill, 30 barrels of fuel and water to Holland’s site beginning near the end of January. The drill will have to penetrate over a kilometre of ice to reach the 300 metres of undersea channel to take measurements.

As the data is collected, some scientists question whether there’s really much for Canadian coastal residents to worry about at this stage.

One study by Ian Joughin, a University of Washington glaciologist, has suggested Thwaites will only lose ice at a rate that creates sea level rise of one millimetre per year — and not until next century. At that rate it would take 100 years for sea levels to rise 10 centimetres.

In a telephone interview last week, Joughin said planning coastal protection and other measures for the more extreme scenarios may not be cost effective at this point, as it may take up to a century before the major risks starts to unfold.

However, Joanna Eyquem, a Montreal-based geoscientist who is studying ways to prepare infrastructure for rising sea levels, said in a recent email that glacier research shows sea level forecasts “are constantly evolving,” and adaptation efforts need to be quicker.

“The question is: How desperate does the situation need to be before we take action?” she asked.

READ MORE: Expert panel says Canada needs to ‘up its game’ on climate data to better adapt

Michael Tutton, The Canadian Press


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Star search: Canadian scientist to travel way back in time using world's largest space telescope – CBC.ca

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A team of astrophysicists may soon be getting a key to unlocking the mystery on the origins of life. 

The James Webb Space Telescope was launched into space from French Guiana in South America on Dec. 25.

With a price tag of $10 billion US, Webb is the largest and most powerful space telescope ever constructed by NASA, the National Aeronautics and Space Administration.

Canadian astrophysicist Tyrone Woods hopes to use it and find the first stars ever created by travelling through time — in a sense. 

“We’re going to be able to look back into this earliest epoch of the universe,” Woods said.

Originally from Edmonton, Woods is currently a Plaskett Fellow at the National Research Council of Canada’s Herzberg Astronomy and Astrophysics Research Centre in Victoria, B.C.

On Dec. 11, NASA’s James Webb Space Telescope was secured on top of the Ariane 5 rocket that would launch it to space from Europe’s Spaceport in French Guiana. (ESA-M.Pedoussaut)

NASA touts Webb as the successor to the Hubble Space Telescope, which was launched in 1990. The new telescope is a collaboration between NASA, the European Space Agency and the Canadian Space Agency. The project has been decades in the making.

Since Webb has a much larger mirror than the Hubble, it can collect more light and peer farther back into time. 

“Light has a fixed speed. It doesn’t travel infinitely fast. It takes time,” Woods said on CBC Edmonton’s Radio Active. 

While light travels at 300,000 kilometres per second, many stars are millions — if not billions — of light years away from Earth. It’s possible that some of the stars we see in the night sky no longer exist. 

Astrophysicist Tyrone Woods, originally from Edmonton, Alta., hopes to discover the first stars in the universe using the James Webb Space Telescope. (Submitted by Tyrone Woods)

Stars are born in areas of dust and gas known as stellar nurseries. To help find the first stars, Woods’s team has built a cosmic roadmap by using computer simulations.

“So conventionally, we had always thought of the first stars as being so very compact and very blue,” he said. 

“We’ve seen that in some of them [nurseries of the very first stars], they would be the perfect conditions for making really massive, really bloated, really red stars.”

Currently, the oldest known star is HD 140283, also known as the Methuselah Star. It is estimated to be 14 billion years old, similar in age to the universe.

Webb is primarily an infrared telescope, which means it sees light that our eyes cannot. It’s possible that by focusing on infrared light, the telescope could find a planet similar to Earth, because infrared is a wavelength our own planet emits. 

“We’re going to be looking in the environment around some very big clusters of galaxies in order to find a magnified light from behind them and get a really, really deep exposure of the early universe,” said Woods. 

Other than the origin of the stars, Woods hopes the new telescope will also help scientists find the first black hole, how gases assemble in the universe, and more about how our own solar system was formed.

6:48How were the first stars formed?

We talk with an astrophysicist about his research on the origins of the universe. 6:48

Webb will spend the next several months getting ready to look into the farthest reaches of the universe by unfolding its mirrors and massive sunshield and cooling down after travelling 1.5 million kilometres from Earth to its intended orbit around the sun.

“Over the subsequent year, we’re going to start to see the first really exciting results,” said Woods.

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