Earth’s last great wilderness

Jack O'Donovan By: Jack O'Donovan
Date posted: 1 February 2019

The kelp forests that wrap around the UK coast are an underwater wilderness facing a crisis. The growing market for products containing kelp could result in their decimation. Could farming it be the answer?

© SNH / Richard Shucksmith

Kelp forests. Our island is surrounded by them, as are the temperate waters stretching from Portugal to Russia and from Ecuador to Southern Australia and New Zealand. So called because of their resemblance to forests on land both in structure and the life they support, kelp are part of the phaeophyceae family – the brown seaweeds.

The fronds of the kelp sway high into the water column and form a canopy. The stipe, or stalk, stretches down to the seafloor like a trunk where the holdfasts – root-like structures – anchor this underwater rainforest to rocks and boulders. It’s a magical habitat, home to fish, crabs, sponges, sea stars and a hunting ground for seals and seabirds. The hustle and bustle among the kelps resembles something we may associate with colourful coral reefs in the tropics.

Underwater Dogfish

The leafy canopy acts as a nursery for juvenile fish, including cod, pollock, haddock and wrasse, while larger, mature fish dart between the watery avenues, and crus - taceans such as crabs, lobster and shrimp scamper among the holdfasts on the safety of the craggy seafloor. This cold water habitat, unlike many other biodiversity hotspots, is not yet feeling the full effects of warming sea temperatures and climate change. Quite simply, this is one of the earth’s great wildernesses – but if we don’t act now, it could be one of the last. Coastal communities and inshore fishers and seaweed hand harvesters have survived for centuries, dependent on the health of kelp forests.

Crab, shrimp and lobster fishers rely on the kelp as a nursery ground and hiding place for juvenile sea creatures to replenish the population. The forests also play an enormous role in reducing the impact of storm damage and wave action to coastal towns and villages. Sustainable small- scale fisheries and sea vegetable hand harvesters have an understanding with the natural balance of the bays and rocky coasts, that if managed correctly will continue to support and protect them long into the future. But, despite this idyllic picture, the fate of our last true wilderness is becoming increasingly uncertain.

Underwater Crab_Kelp

The current kelp hand harvesting licence specifies that the holdfast, stipe, and a large part of the frond – the leafy canopy section – are to be left intact to allow the plant to regenerate. However, mechanical kelp harvesting threatens to remove vast swaths of precious habitat from our shores and from temperate waters the world over. Kelp dredging involves using a steel dredge claw, or comb, to pull entire mature kelp plants from the seafloor.

It’s a method that has been practised for quite some time in Norway, France and Iceland. And although kelp plants are incredibly fast growing at particular times of the year, until now, the sustainability of kelp harvesting has focused on the regeneration of the plant biomass alone, with little or no focus given to the recovery of the ecosystem the kelp supports and the fish and wildlife that rely on it. Scotland’s wild west coast is the latest area to be targeted for mechanical kelp dredging. A licence request has been lodged by Ayr-based Marine Biopolymer Ltd.

Studies estimate that seaweeds and kelp forests sequester and store around 173 tonnes of carbon a year – that’s equal to an entire year’s worth of carbon emissions from New York city. Tearing away annually up to 30,000 tonnes of the very thing that stores carbon and gives a home to the organisms that continuously consume carbon, would be a backward step on progress to alleviate the impacts of climate change and would put the future of Scotland’s coasts and planet Earth in legitimate jeopardy. But it’s not just the underwater creatures and the carbon storage that such dredging will impact.

A study on cormorant feeding behaviour in Norway showed that these foraging seabirds chose to feed in greater numbers in unharvested kelp forests than in areas where wild kelp had been harvested. Dive studies showed that harvested sites contained 92% less small gadid fish (cod, haddock and pollock, for example), than unharvested wild kelp forests. This in turn may have potential effects on recovery of commercially important fish populations and on a key part of the food chain that supports the cormorants, other fish and marine mammals such as seals.

Underwater Pollock_Kelp

When the licence was submitted to mechanically dredge kelp in Scotland, coastal communities, inshore fishers, marine experts and many other local stakeholders made their voices heard by responding to a government consultation. Coastal dwellers quickly rallied to put a stop to the kelp dredging. Ailsa McLellan, a Scottish oyster farm owner, said: “When I first heard about the plans to dredge for kelp it was like a physical blow. This would be taking ‘fishing down the food chain’ to its absolute limit by removing the very bottom of the marine food web.” A petition has so far generated over 17,000 signatures and a letter, from businesses against kelp dredging, now has 142 businesses signed up, including fishermen’s associations, the Scottish Scallop Divers Association and the Scottish Shellfish Association.

Scotland’s shores are not unfamiliar with battles to protect its fragile marine environment. Howard Wood and the Community of Arran Seabed Trust (COAST), put up a 13-year campaign to save the dwindling biodiversity that once thrived in the island’s Lamlash Bay. It resulted in Scotland’s first no-take zone, which excluded all human activity to give the life that once flourished a chance to recover from years and years of damaging scallop dredging. On the current threat of kelp dredging,

Howard Wood said: “Marine Scotland’s record of encouraging completely unsustainable extraction of natural resources continues. Our inshore waters could provide thousands of sustainable livelihoods from well managed creeling to hand gathering of seaweeds. Now consulting on an even more ecologically crazy project – mechanically ripping out kelp across the majority of the west of Scotland – tens of thousands of Scots are protesting including the majority of fishermen”.

The proposed mechanical harvest aims to extract only 0.15% of Scotland’s standing kelp stock per annum over its five-year licence. However, studies have shown that the recovery of kelp forests after initial harvesting is largely due to the existing understory made up of juvenile kelp plants. A study on the regrowth of kelp forests in Nord-Trøndelag, Norway, has shown that four years after harvesting the kelp, biomass had recovered to pre-harvest levels and that the initial understory must have largely contributed to the restocking, but the new understory itself was significantly less than the original.

With this in mind, if the understory becomes smaller after each harvest, the time between harvests will need to be increased or else the kelp will simply reduce year on year, meaning that supplying the demand will require more wild kelp forest to be explored for harvesting. According to a report by Scottish Government, coastal communities are particularly dependent upon sea fishing including in the Western Isles where over 20% of jobs are fisheries related. The possibility of dredging kelp forests in these areas could pose a knock-on effect through the fishing and marine tourism industries.


Government figures say tourism in Scotland grew by 30% between 1970 and 2000 and Scottish Natural Heritage suggests that £9.3 million was generated by marine tourism alone as early as 1998. By 2016, the Scottish Government reported that £3.7 billion was generated annually by marine recreation and tourism activities. Kelp forests support a wealth of Scotland’s wildlife that keeps people coming back to visit again and again. To harvest the very base of the ecosystem could have detrimental effects not only for Scotland’s marine life but to the communities that rely on the income it generates.

The Scottish campaign group, ‘No Kelp Dredge’, says there’s no reason why kelp can’t be farmed as in other countries. It advises: “Kelp can be farmed. It is farmed in Norway, the Faroes and at Rathlin Island between Ireland and Scotland. If alginate companies want kelp they must invest time in researching how they can make farming viable for them. Dredging the wild beds must never be an option”. Reports have been compiled by the Irish Sea Fisheries Board on seaweed aquaculture largely focused on macroalgal cultivation used as feed for abalone and urchin aquaculture.

Kelp farming is also being developed for the biofuel industry. In these projects, kelp Laminaria digitata and Palmaria palmata are being grown on long lines in various bays in the South and West of Ireland. Experiments are ongoing to determine the best possible system for various kelp species. After much investigation it was deemed that the techniques for kelp farming are in need of further and continual development to create a viable business and harvest model that will supply a growing demand. If pharmaceutical, agricultural and biofuel industries require kelp, and are legitimate in their claims as sustainable industries, then it is time for committed investment in a sustainable kelp farming system.

Anemone on kelp - Ben James/SNH

A system that supports local employment, high quality produce and a world leading system for the blue economy, not the decimation of this great ocean wilderness and the security of coastal communities. We can no longer afford to turn a blind eye to the intricacies of our wild places and deem kelp forests as ‘monocultures’, when it is proven the world over that they support a bustling biogenic habitat bursting with the colour, life and sounds of the hundreds of species they support. If protected today, our native kelp forests could thrive as one of the Earth’s last great wildernesses.

Thankfully the efforts of the No-kelp dredge group have been successful and Scottish government has halted all mechanical kelp dredging licence applications until a full review into Scotland’s potential kelp industry has been completed.

Support to protect our native kelp forests however is still needed in mass. The Bantry Bay kelp group in county Cork Ireland are fighting hard to protect the kelp forests that provide stability to Ireland’s marine wildlife, local fishers and eco-tourism businesses.

This article was written by Jack O’Donovan - Campaigns Officer (MCS), for our winter 2018 membership magazine ‘Marine Conservation’. If you’d like to receive our fantastic quarterly magazine straight to your door, you can become a member from as little as £3.50 per month.


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Did you know?…

Scotland has 10% of Europe’s coastline

Over 650 species of seaweed live and thrive around our shores

MCS established its Scotland office and programme in 2000 in Edinburgh