April 16, 2024

Ddeep in the hostile waters off Canada’s west coast, in a narrow channel surrounded by fjords, lies a coral reef that scientists believe “shouldn’t exist”. The reef is the northernmost ever discovered in the Pacific Ocean and offers researchers a new look at the resilience – and unpredictability – of deep-sea ecosystems.

For generations, members of the Kitasoo Xai’xais and Heiltsuk First Nations, two communities along the central coastal region of British Columbia, have noticed large groups of stonefish congregating in a fjord system.

In 2021, researchers and First Nations, in collaboration with the Canadian government, deployed a remote-controlled submarine to explore the depths of the Finlayson Channel, about 300 miles northwest of Vancouver.

On the last of nearly 20 dives, the team made a startling discovery – one that was only recently made public.

“When we started seeing the live corals, everyone was in doubt,” says Cherisse Du Preez, head of the deep-sea ecology program at Fisheries and Oceans Canada. “When we then saw the vast coral fields in front of us, everyone just let go. There were a lot of pure human emotions.”

Despite existing in absolute darkness, the submarine’s lights captured the rich pinks, yellows and purples of the corals and sponges.

The following year, the team Lophelia Reef, or q̓áuc̓íwisuxv, as it was called by the Kitasoo Xai’xais and Heiltsuk First Nations. It is the country’s only known living coral reef.

The discovery is the latest in a series of cases in which indigenous knowledge has led researchers to areas of scientific or historical interest. More than a decade ago, Inuk oral historian Louie Kamookak compared Inuit stories with explorers’ logs and journals to help locate Sir John Franklin’s lost ships, HMS Erebus and HMS Terror. In 2014, divers located the wreckage of the Erebus in a location that Kamookak suggested they search and use his directions. found the Terror two years later.

The remote controlled submarine is lowered into the Finlayson Channel, British Columbia, Canada. Photo: Cherisse Du Preez/Fisheries and Oceans Canada

The lophelia corals that make up the reef are typical of those found in the deep Atlantic and regions of the Pacific south of California. The largest reefs can span several kilometers, and take tens of thousands of years to mature. In the case of q̓áuc̓íwísuxv, the reef spans 10 hectares (25 acres) of “thriving” corals.

“The Pacific Ocean has some of the oldest water in the world, which means it has low levels of oxygen, which makes it difficult for coral to survive,” says Du Preez.

The north Pacific also has high levels of acidity, which dissolves the calcium carbonate structures of coral. “So for the longest time, we didn’t think the components needed to support a reef existed here,” she adds.

The team suspects the reef’s unique location, in a fjord with abnormally cold water, helps explain its ability to thrive. The reef where the coral is found is also in a region of water column mixing, where highly oxygenated water is pushed down towards the coral.

“At first you think a reef like this must be one of a kind. But it can’t be. That’s not how nature works. So now we’re going to find the others who need to be out there,” says Du Preez.

Last week, Canada’s federal fisheries department announced all commercial and recreational bottom contact fisheries, including midwater trawling, could no longer fish in the area around the reef.

Despite efforts to protect the area, dead coral found along the periphery of the reef highlights how lophelia coral is uniquely vulnerable to warm water and increased acidification – hallmarks of a changing climate.

“These reefs are cemented to the rock and if you dissolve the base, it will literally slide down and crumble into the depths,” says Du Preez. “But if we can control all the activities that happen in the area, we give this reef the best chance to survive climate change – and maybe even colonize new areas.”

Besides the lophelia coral, researchers also found a large glass sponge reef. It is unlikely that the two species have met anywhere else in the world.

“In the deep sea there are no rules,” says Du Preez. “So you can make these two species live together, fight or work together. Few things are more exciting for scientists than seeing things that seemed impossible happen right in front of us.”

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