By Nick Morrison

Siân Tarrant, a marine biologist is also the Sheep Dyke warden for North Ronaldsay.

The North Ronaldsay sheep are members of the northern short-tailed group and are quite small only about 25 kilos in weight. They were formerly found throughout Orkney .

The sheep Dyke is about 12 to 13 miles long and in former years the islanders would keep it in good repair . Now there are only 60 elderly islanders left . Due to winter storms about one quarter of this Dyke is currently in need of repair or replacement.

The North Ronaldsay sheep are also extremely good for conservation grazing which removes coarse vegetation in the winter .

Dr Katerina Theodoridou of Queen’s University Belfast, associate professor in animal nutrition described the world’s needs for increasing amount of milk and meat .Only 30% of the planet is dry land and of that 30% very little is actually suitable for agriculture .Feeding animals on seaweed looks like an obvious way to go. Especially as it can be farmed .Even small amounts of seaweed in the animals diet has
been found to lead to significantly lower emissions of the greenhouse gases methane and ammonia .

The sheep’s stomach contains enzymes and bacteria which are able to break down the
polysaccharides in the seaweed . Dr Jessica Adams of Aberystwyth University and Dr Luisa Ciano of Nottingham University described ongoing research into these enzymes .

Polysaccharides are extremely tough molecules even to the extent of being found in fossils .If enzymes can be found to break down these polysaccharides there is a lot of waste material from industry, leaves, sawdust and the like that could be used to make biofuel oil and chemical feedstocks .

You can watch the whole talk from the Orkney International Science Festival here: