Forests of kelp have been disappearing from swathes of the Sussex coast because of the damage done to the seabed by commercial trawling. But now, thanks to a byelaw that went in force in March, marine life could be returning.
A 300km2 area of the sea that’s seen vital kelp stocks disappear to just 4% of their former abundance is now protected under a byelaw that bans trawling along four kilometres of the coast.
Vital kelp forests have been destroyed by commercial trawlers that scrape everything off the seabed, ripping seaweeds from the rocks on which they grow.
It means there is nowhere for fish to spawn, or young creatures to reach maturity.
Kelp, which is actually a form of algae rather than a plant, thrives in cold, shallow waters, and is also a fantastic absorber of carbon dioxide.
But it’s also sensitive, and oceanographic conditions can have a devastating impact on its survival –from warmer waters to storms to aggressive trawling.
Now, thanks to years of work by the Sussex Inshore Fisheries and Conservation Authority (IFCA), the Nearshore Trawling Byelaw bans the practice all year round between Shoreham and Selsey Bill, and across a sea area of about 300km2.
A partnership including the IFCA and Sussex Wildlife Trust is working to monitor the area to see if the trawling ban will have the desired effect.
Sally Ashby is Sussex Kelp Lead with the Sussex Wildlife Trust.
“Already we are seeing the return of certain seaweeds,” she says. “We are doing active research – mapping and monitoring the kelp to study and understand where we can expect it to regenerate more quickly, and what its genetic make-up is.
“We have underwater drones collecting eDNA (environmental DNA), and while we’re not getting the old species back straight away, where we are seeing the return of some kelp it’s showing it’s helpful already.”
The ocean nursery
On a recent dive, Sally could still see trawl lines on the sea bed.
“But already I could see life returning – baby crabs and baby lobsters,” she said. “Already there have been more black sea bream noted. They nest in gravel beds, which trawling destroyed. It’s also been linked to more dolphin sightings. If you leave nature alone for long enough it does come back.”
Kelp is known as an ‘ecosystem engineer’.
Not only does it provide safety and a spawning home for marine life, it also draws CO2 out of the air when it photosynthesises.
“Molluscs and whelks eat the kelp, and the fish eat them – so it attracts them back,” says Sally. “It’s the function of a whole complex food web. Once you have that you have a thriving food chain. We don’t know the link for sure, but we do know there has been a massive decline in fish, lobster, crab – they have really been struggling.
“We know that they rely on the kelp environment for their juveniles – and the kelp is the ocean’s nursery for juvenile animals, it gives them hiding places instead of their being exposed to the open ocean. We’ve been losing the nurseries.”
Tim Dapling is Chief Fisheries & Conservation Officer for the IFCA.
“This is a very important habitat, where there used to be especially large kelp beds,” he says. “We issue the local fisheries their permits, and we know from them that their catch has been in decline recently and we’re doing all we can to improve that situation.
“Lobsters take about five years to reach full maturity, and while they do so it’s particularly important that they have access to the right habitat – like the cover that kelp provides – so they are not eaten by a multitude of predators like skate and dog fish.
“They cast their shell in stages as they grow, and when they cast their shell they are extremely vulnerable.”
The return of marine life can only be good for not only the marine life but also local fishermen, says Deputy Chief Fisheries & Conservation Officer Dr Sean Ashworth, who was instrumental in getting the byelaw implemented.
“We are delighted that the local community and central government have recognised the critical importance of looking after Sussex marine wildlife and the local fisheries that critically depend upon it,” he said. “We look forward to seeing a regeneration of the lost kelp forests and an associated improvement of the inshore fishery.”
Dave Gomm sells fish on Goring Green, Worthing. A back injury now prevents him from going out to fish, but much of his stock comes from local fishing – and it’s far from abundant, he says.
He says fishermen broadly welcome the banning of near-shore trawling, because they genuinely recognise the importance of sustainability.
“We haven’t seen much sign of an effect yet, but it takes time, and if it helps fish to breed it will be overall a good thing,” he says. “Fishermen are surviving, and that’s how you would describe it. That’s why it’s called fishing and not catching.”
Because the bigger commercial vessels are unobstructed from bad weather conditions that can prevent the smaller boats from going out, smaller fisheries are being priced out of the market, much like corner shops losing out to the mammoth supermarkets, Dave says. He used to be one kiosk of around 12 selling fish – now he’s on his own.
He remembers when kelp was so abundant off the Worthing shore that storms would drag it from the sea and dump it in huge piles on the beaches. After a while the rotting seaweed could be scented from Findon.
He says it’s a myth that local farmers took much of it away as fertiliser – there was just too much of it.
“It was a massive operation, coming and collecting it – it wasn’t as simple as a farmer coming down and putting some in a plastic bag,” he says. “If it gets like that again it won’t be ideal, but that’s another story. Overall I think it will be beneficial.”
Sally Ashby agrees that commercial fisheries have ruined smaller fisheries.
“Some of their licences some aren’t even UK based,” she says. “We want to put the local fishing community back at the heart of our environment. It’s been so tough for them, and that’s what we want to bring back.”