A campaign to save the unique seaweed-eating sheep of North Ronaldsay and to restore the historic 13-mile dyke which protects the rare breed has been stepped up.
Around 2,500 North Ronaldsay sheep inhabit the shoreline of Orkney’s most northerly isle and survive solely on the kelp churned up by the sea.
Islanders are leading a campaign to restore the dyke and preserve the flock which is owned by around a dozen North Ronaldsay residents.
The dyke not only contains the sheep from other breeds but keeps them away from grass on the island given their special diet has made them vulnerable to copper toxicity.
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The wall, probably the largest continuous dry stone dyke in the world, is Grade A listed but every year sections fall away due to the weather, waves and its age.
While volunteers work with local people to restore the dyke during a fortnight in the summer, permanent staff will be now be recruited to help lead the preservation of the wall given the pressing need for its restoration.
It is hoped more volunteers will be attracted to North Ronaldsay as a result with hopes to set up training in dry stane dyking.
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Heather Woodbridge, a director of the North Ronaldsay Trust, said: “The dyke is Grade A listed - the same as Edinburgh Castle - but it is almost as it is forgotten about.
“The dyke is really important to the survival of the sheep. It’s important to keep them on the shore and it is also symbolic of the old ways of farming. Once it goes, it goes.
“We really need help to keep it maintained and we have been working really hard to get to this point. Things are really starting to happen now.
“There are always some bits of the dyke that go down each year so its repair is an ongoing task. It is not a quick fix and we need a sustainable plan for the future.”
The sheep have been on the shore since 1832 when they were moved off the land to make way for more lucrative cattle with the wall built by the laird to keep the sheep from the pasture.
It is believed that, apart from a single kind of lizard from the Galápagos Islands, they may be the only animals in the world that can survive entirely on seaweed.
Males stay on the shore all year round with the breed the fattest during the winter when the storms churn up vast amounts of seaweed.
Pregnant ewes are moved away into stone enclosures - or punds - in the Spring with the “punding” organised to coincide with the full moon and high tide.
This makes it easier to catch the sheep given the high water levels reduce the space where they can run to.
The mutton from the North Ronaldsay flock is well regarded and was served to the Queen on her Diamond Jubilee. The sheep’s wool is spun on the island and sold far and wide.
This year, dozens of volunteers arrived on the island to assist locals rebuild the wall during the two week North Ronaldsay Sheep Festival in the summer.
Around 320 paces - or metres - of wall were restored with the results hailed as a great success.
Ms Woodbridge said: “The people who came here really fell in love with the island and the culture of the place. They really felt they were doing some good.
She added: “Islands are fragile. You look at what happened at places like St Kilda. That’s not going to happen here. We’re not going to let that happen.”
The population of North Ronaldsay has fallen from almost 550 in the late 1800s to fewer than 50 today.
The 2018 North Ronaldsay Sheep Festival will run from July 29 to August 10 and applications are now open for volunteers.
The stretches of wall to be restored during the fortnight will be decided by the island’s Sheep Court which was set up in the mid-1800s to manage animal numbers on the island
During the 1970s, the father of Adam Henson, farmer and television presenter of BBC’s Countryfile, led the first major conservation project of the North Ronaldsay sheep.
Joe Henson MBE was one of the original founders of the Rare Breeds Survival Trust which bought the island of potential Linga Holm, off Stronsay, to create reserve flock of the breed.
It was feared at the time that oil exploration in the area could potentially pose a risk to the breed.
The sheep were later distributed in small flocks across the mainland.
It is understood that the sheep are the only landa animals able to survive solely on seaweed apart form the Galapagos marine iguana.