There are locals, says Philip Price, who will tell you that the seagrass beds in Loch Craignish were once much vaster than they are now. A creeler who recalls pulling up pots, covered with the grass; a villager who remembers how just over the hill, Loch Beg, was carpeted in the stuff.

That chimes with research that shows how dramatic the disappearance of seagrass has been from our coastline  One report has estimated that we have lost 95% of what was once in UK waters. As a result, the fragments of such meadows that remain now are precious refugia,

One of these is at Loch Craignish on the West Coast, and a group of us have come here to snorkel over seagrass; to fin through its meadows and witness some of the work that community-led organisation  Seawilding is doing to restore and expand the beds on the loch, as well as its restoration project with native oysters.

I’m interested in what it tells us about how the Clyde, the subject of this Herald series, and other coastal areas around Scotland, including my local Firth of Forth (the site of its own seagrass and oyster projects) can also be restored.

We arrive on the kind of blazing September day that makes Scotland look like a swimmer’s paradise, waters turned turquoise in the sun. The verdant blades swirl out ahead like crowds dancing. At one point they reach so high it’s a matter of parting them to float through as they tickle our chins and masks.

The snorkel group is guided over seagrass meadows by SeawildingThe snorkel group is guided over seagrass meadows by Seawilding (Image: Gethin Chamberlain)

Seagrass is a remarkable plant, as Price, Seawilding’s bearded, sunkissed general manager, relates. It is, he says, “a fully functioning seed-making, flowering and pollinating plant that lives underwater in the sea and it is the only one that does it”. There are various species of this plant, but the one at Craignish is subtidal.

What also makes it special is what it does to the seabed. By being rooted down into the sand, it creates structure where there would otherwise be mostly mud.

Price describes it as a kind of ‘ecosystem engineer’. “If you put structure down, you instantly get more life - and this is one of the main roles of seagrass. That structure does all sorts of incredible stuff. It binds sediment together. It captures carbon and puts it down in the sediment. It creates homes for a whole series of different lifeforms.”

Biodiversity studies in Loch Craignish have found 155 species in the wider loch, 106 of which are found in the seagrass meadow. A  tiny area, just 0.4% of the loch,  contains 68% of its biodiversity.

“In the past,” he says, “it would have been everywhere it could grow. But it is mostly gone from our coastlines". About five hectares of fragments remain in the loch, but Seawilding believe that there are possibly 90 hectares of suitable habitat.

“Seagrass," says Price, "was around before humans. It would have been like the ancient forest covering Scotland: that level of wilderness under the sea. That’s the thing you realise very quickly when you start to work underwater. We’ve lost the wilderness under the sea. It’s gone. It’s a very flat monoculture now.”

The reasons for the disappearance of seagrass are multifold and chiefly involve humans: pollution, dredging and its removal in, for example, clearing channels for shipping.

Seagrass in Loch Craignish, dotted with its tiny flowersSeagrass in Loch Craignish, dotted with its tiny flowers (Image: Gethin Chamberlain)

Part of the problem, says Price, is that seagrass can’t really function in small fragments. “It has evolved over millions of years to have huge coverage, which means its reproductive cycles are dependent on that coverage. It’s arguable that maybe seagrass can never make a full recovery without help. So that’s why we’re stepping in and helping.”

This trip has been organised by one of Seawilding's funders, Highland and Islands Environment Foundation. Like Arran COAST in the Clyde, Seawilding is community-led.  It came out of a local group, the Craignish Restoration Marine and Coastal Habitat (CROMACH), and their origin touches upon an issue that is relevant to what we, in this Herald series, have been looking at regarding the Clyde too - who has a voice and an impact on our waters.

Price observes: “For the last fifty, even 100 years, how the inshore waters  has been managed was dictated by the people exploiting those waters - not the people living there but the people making money out of those waters. And yes we totally believe they should have a voice. But we also believe that the wildlife living in there should have one, as should the people living by and reacting with that water.”

The restoration of seagrass is, for him and his colleagues, as well as the volunteers who annually help out,  a positive action they can be involved in and way of making a difference.

The ‘seawilding’ of seagrass in Craignish has been an ongoing experiment in regeneration, not all of which has worked. After various failures -  plantings, for instance, in an area of the loch that was too anoxic - they seem to have come to a method that appears to be working, based on a technique developed in Canada.

Instead of foraging and planting seeds, they harvest whole plants from existing donor beds, and place them down in a restoration area, on the edge of existing seagrass, weighted down by small iron rings.

Seagrass restoration is notoriously challenging, but Seawilding at Craignish seems to have one of the best rates in the country. The 5% they believe they have achieved this year is remarkable. But still, says Price, “it's not good enough”.

 “We’re working in a really new sphere of restoration and we haven’t cracked it yet. But we’re getting there.”

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Snorkelling over the wafting fronds, through light shafts picking out fragile seagrass flowers,  we emerge from a patch of meadow, thick as hayfield, into shadow muddy area dotted with plants. There's a sudden yelp of enthusiasm as we trudge through the mud, as Price notices a small plant, adjacent to a larger seagrass tuft.

"That's new!" he says. This is regeneration. It’s a process that it’s also possible to see in drone imagery taken from above. The patches are spreading. They are beginning to join together.

Out in the shallow waters of the loch, snorkel past, Seawilding’s other project; small submerged cages home to native oysters that are part of work that has introduced  350,000 such oysters to the sea.

Vicky Allan holds up a native oyster from the Seawilding restoration projectVicky Allan holds up a native oyster from the Seawilding restoration project (Image: Gethin Chamberlain)

“Why are we interested in oysters?" says Price  "They actually do exactly what the seagrass does. They create structure and reef up. Oysters grow on other oysters.”

Oysters are also a species that have been overfished and impacted by humans in many parts of the world,  to the point of near extinction. The Firth of Forth, for instance, no longer home to European native oysters (save for some few that have been reintroduced)  once saw fleets bring in around 13 million a year.

Research has estimated, says Price, that at one point 6.2% of the entire North Sea was oyster reef, an area of 35 350 km2.  “That’s twice the size of Wales," he calculates. Some reports say that there were reefs seven metres tall, as high as a two-storey house. 

Both oysters and seagrass, because of how they function in ecosystems,  are focus species in rewilding the sea. But at the moment projects are still small, and the challenge remains is how to scale up. There has also, in the UK,  been a dearth of much-needed “baby oysters” over the past year. Hence Seawilding are also thinking about establishing their own hatchery,.

Most importantly though, what is needed for both species is a higher success rate and a way of scaling up - and Seawilding is already looking at ways of achieving this.

Cages containing restored native oysters in Loch CraignishCages containing restored native oysters in Loch Craignish (Image: Gethin Chamberlain)

The scaling up needs to happen, Price explains,  by multitudes. With oysters, he says, the shift needs to be made from introducing hundreds of thousands to millions. “Our CEO has got this ambition of making a billion oyster project and putting a billion oysters down on the seabed. These are the ambitions we really need.”

How does this relate to the Clyde? Already, in the firth, there has been one experimental project attempting oyster restoration at Largs Yacht Haven, run by Zoological Society of London. Its project lead, Celine Gamble, told me it was chosen because there is historical evidence of European native oysters and also two remaining populations.

READ MORE: The Future of Clyde Fishing – find all articles in series here

There are patches too, we know, of seagrass in the Clyde sea. In the marine reserve at Arran, and off Pirmill at the North West of the island, for instance. But a feature of seagrass is that it is also under documented. We don’t know where much of it is, in order to protect it.

It’s also worth noting that seagrass has some links to another story at the heart of this series, the cod.

Research has shown that the young Clyde cod, at only a few centimetres long, are found mostly in shallow rock areas, near kelp forests and seagrass beds. These areas are sometimes refer to as ‘nurseries’ or ‘nursery habitats’.

Could protecting and restoring our seagrass, in certain places, also help the cod too