In 2015 Tasmanian marine researcher and PhD student Cayne Layton and the other members of his team, faced an urgent dilemma… Tasmania’s iconic kelps were being wiped out by climate change, hungry sea urchins, and rising temperatures in the Eastern Australian Current.
The Australian Government declared giant kelp (Macrocystis pyrifera) forests as endangered in 2012. Around 95% of giant kelp forests had disappeared as global warming increased the strength and temperatures of the Eastern Australian Current (EAC), creating an environment too hot for the giant kelp to survive.
In early 2015 the team, led by marine ecologist Professor Craig Johnson from the University of Tasmania, planted more than a hectare of a different kelp species, common kelp (Ecklonia radiata), in an experiment to test how habitat disturbance affected the health and stability of kelp forests ecosystems. Within six weeks the area was crammed with a wide range of animals and other algae species, and from this project stemmed the team’s future exploration into kelp forest restoration.
A follow up initiative in 2018 focussed on identifying giant kelp individuals that might be more tolerant to the warmer waters, and which might be used to help re-seed areas of lost kelp forest.
The giant kelp was grown in a lab and planted out in the ocean in January 2020, and Layton spoke to Cosmos Magazine (“The Unsung Reef” by Stephanie Stone, edition #86 page 48-55) in May of that year.
“What we’ve done is outplanted some of those super kelp into the wild,” he said at the time. “We’ve got three sites in south-east Tasmania where we’re attempting restoration for giant kelp. At those sites we’ve planted some of the five families that are the best performers.”
What happened next?
Now Dr, Layton told Cosmos in in November 2023, “Super Kelp” as a name was ditched. “People thought we were potentially genetically modifying these giant kelp.
“It wasn’t a conscious decision, I have just moved away from using [super kelp] because we thought it overly simplified something that’s quite complex, and since some people misunderstood what we were doing”
Instead, Layton now refers to the kelp as being “naturally more tolerant to warmer water.” He admits the new identifier is not flattering.
“We were sampling from the remaining giant kelp patches that still occur in Tasmania, and we’re just finding those individuals that are naturally more tolerant of warm water.”
But what of the trial? “That was the first time we planted giant kelp back into the ocean. They were the first proper trial that we had done.”
And then a major disaster: The project was halted due to COVID-19. As research on COVID was still undeveloped, the University of Tasmania didn’t want to risk the health of the divers or the spread through the diving gear.
“It was a difficult year because of having to deal with shutdowns and diving restrictions.”
The restrictions didn’t ruin the entire project, and following another planting in late 2020, much of the kelp grew to adult stage by 2021.
“We had adult kelp that had grown 12 meters within the first 12 months. So that is a metre a month, [and] they were reaching the surface.”
“We had started to get a sense that, hey, we can do this. We can start to restore these little areas of giant kelp.”
In 2022, the kelp planted back in 2020 began reproducing.
“Just before Christmas 2022, we found for the first-time natural baby giant kelp that were settling and recruiting and growing in our restoration trial areas that had come from the kelp we had planted years earlier.”
Coming to this stage of development and research wasn’t easy. Layton says the Great Barrier Reef receives 100 times more research funding than Australia’s kelp forests. Like many scientists, Layton also has job insecurities because of minimal funding, requiring him to continually search for supporters and for his own pay.
“That’s the reality of working in science at the moment.”
Layton moved back to NSW in 2023, and for now is still a Research Fellow at the University of Tasmania, but has not abandoned his research or visits to Tasmania’s giant kelp forests.
“It wasn’t the best move professionally… [but] it was done for personal reasons, just to be closer to family after being away for over a decade.”
Throughout this year Layton and the team have continued monitoring and observing newer experiments that have planted almost a hectare of giant kelp.
“Even though we still have a long way to go, we’ve started to see that maybe we can do it at [a large] scale. Given enough time, we can perhaps start to restore larger areas of giant kelp forests.”
Indeed, the project has since expanded beyond the university to involve a large range of collaborators, from local businesses, environmental organisations, and other researchers. All of whom are trying to upscale these plantings to see whether restoration can be effective at scale and might be one solution to slow the loss of Tasmania’s amazing kelp forests.
Although, these projects might only be buying time. The restoration isn’t a silver-bullet solution, stopping climate change is the priority. “If we don’t stop climate change, no amount of us finding these slightly more tolerant giant kelp varieties is going to change things.”
Eight years on from his large PhD experiment, Layton’s distress hasn’t dissipated.
“It’s pretty tough. It certainly is something that keeps me up at night sometimes and is a real source of worry.
“We are seeing some of these ecosystems, some of these giant kelp forests, which can be as tall as a five storey building, literally disappear during summer time.”
“It’s really scary, and those summer temperatures are getting warmer and warmer.”
“ Many of the [Tasmanian] locals are actually worried and concerned about how warm the water is, because it shouldn’t be that warm. And even in the 10 years that I lived in Tasmania, I noticed a change. The scale and the rate at which our oceans are changing is pretty alarming.”
Do you care about the oceans? Are you interested in scientific developments that affect them? Then our email newsletter Ultramarine is for you. Click here to become a subscriber.
The Ultramarine project – focussing on research and innovation in our marine environments – is supported by Minderoo Foundation.