How seaweed-eating sheep could hold key to lower gas emissions
A rare breed of Scots sheep that’s considered a delicacy could also play a part in fighting climate change. Rohese Devereux Taylor reports
THERE are no other beasts like them in the world and now the sheep of North Ronaldsay could be on the front line in Scotland’s fight against climate breakdown.
The sheep, found on the northernmost island in the Orkney archipelago, are the only herd to eat an exclusively seaweed-rich diet, grazing on the macroalgae that stipples the shoreline.
The diet favoured by the hardy flock gives their meat a “gamey” flavour that is appreciated as a delicacy in the best restaurants across the UK, but recent research has shown animals enjoying a diet that includes seaweed produce less methane than those eating grain-based animal feed or grass.
Researchers at the James Hutton Institute have partnered with Davidsons Animal Feeds, a Shotts-based animal feed mill, to explore the possibility of protein-rich UK seaweeds to replace some currently used ingredients in the production of ruminant animal feeds, taking into consideration the associated benefits in terms of meat quality and a reduced carbon footprint.
Methane is a powerful greenhouse gas that, while it doesn’t stay in the atmosphere as long as carbon dioxide, is more dangerous to the climate due to how effectively it absorbs heat. It is estimated about 25 per cent of global warming is produced by methane.
The Knowledge Transfer Partnership (KTP) between the world-renowned research organisation and the animal feed company aims to pinpoint the ideal seaweeds for use in ruminant feeds based on their nutritional value, with a particular interest in protein content.
It is hoped the findings could reduce the reliance on produce imported from overseas and reducing transport emissions.
Dr Gordon Mcdougall, a research scientist in the KTP’S Environmental and Biochemical Sciences group in Dundee, said seaweeds have the potential to provide greener feeds to support Scotland’s reputation as a producer of high-quality meats, as well as providing more jobs in coastal areas.
He said: “Increased cultivation of seaweeds in the UK may help bolster our coastal communities by providing a new source of income. In addition, seaweed-plus feeds may bring other nutritional benefits as they are rich in vitamins and minerals.”
The North Ronaldsay sheep are the oldest breed in Northern Europe and among the oldest and most rare in the world. According to an investigation of old bones on Orkney, their DNA is 8,000 years old.
Last June, a plea was made by the North Ronaldsay Trust to find a warden to look after the historic stone dyke that protects the herd after it was found too hard to maintain by the dwindling island population after bad weather.
The 6ft high, 13-mile dyke was erected using beach stones and encircles the entire island to keep the sheep on the rocky foreshore and away from grassland where they can mix with other breeds.
After the native sheep were pushed off the pasture and on to the foreshore in 1832 to utilise the island’s acreage, the laird, John Traill, ordered the construction of the dyke, now protected by conservation law and Grade A listed, to keep the sheep on the shore. The flock flourished in their new habitat and are now genetically adapted to thrive on their foraged seaweed diet.
Marine biologist Sian Tarrant answered that call after a search that saw interest from across the globe. It is her job to maintain the dyke for the next three years.
It is believed that, apart from a single kind of lizard from the Galapagos
Islands, they may be the only animals in the world that can survive entirely on seaweed.
Over the next three years, KTP associate David Beattie will work from a selection of candidate seaweeds of appropriate dietary suitability to produce prototype feeds at suitable volumes using Davidsons hi-tech feed mill.
Commenting on the project,
Mr Beattie said: “I see this project as an exciting opportunity to be involved in such multi-faceted research. While I will be relying on my scientific knowledge to analyse candidate seaweeds for feed production, I will also be able to develop new skills in market research and product development.”
Jim Berryman, knowledge transfer adviser at the Knowledge Transfer Network which delivers the KTP programme, said: “KTPS provide a very useful mechanism to link ideas and expertise to enable innovation, and this is a particularly exciting initiative responding to the ever more urgent need to seek environmentally-conscious solutions to a wide variety of challenges.”
This is an exciting opportunity to be involved in such multi-faceted research