A head start for Mowi Scotland's newest salmon farm

Mowi Scotland’s newest fish farm off South Uist was stocked only a couple of weeks ago but its staff won't have to wait too long before the site's first harvest, as the fish the site received are already quite well advanced.

The Stulaigh South farm is at a high energy site – an area of the ocean with strong currents, higher wave activity and good water exchange – and is best suited to larger, more robust fish. It has been stocked with salmon from Marulaig Bay, another Mowi marine farm in the same area.

Marulaig Bay was stocked in October, meaning fish from that site are now likely to weigh between 1.5 and 2.5 kilos.

All things being equal, Stulaigh’s first harvest could be made in just a few months.

Stulaigh South is equipped with six 200-metre circumference pens, marking another step in the company’s direction of travel towards bigger pens at higher energy sites.

And that step is bigger than many people may realise by looking at the numbers.

A 200m pen may only have a 25% bigger circumference than a 160m pen, but the area of the larger circle in 56% bigger. Consequently, the volume of the net beneath the collar is 56% bigger than a 160m pen net of the same depth. That means the Stulaigh farm can accommodate its maximum allowed biomass (MAB) of 3,000 tonnes of salmon in just half a dozen of the larger pens.

Riding the waves

Stulaigh South is not the first Mowi Scotland site to be equipped with such large pens – that was Hellisay, off Barra - but they’re still unusual in Scotland, although not in the Faroes, where they have proved robust enough for Mowi’s exposed sites. The bigger the pen, the better it is able to ride the waves.

That’s what made 200-metre pens suitable for Stulaigh, a Mowi spokesperson told Fish Farming Expert.

Seven members of staff will support the new Stulaigh South farm including three new apprentices who are working towards their National Progression Awards in Aquaculture and Modern Apprenticeship qualifications, Mowi reported in its staff newsletter, The Scoop.

Hands-on experience

The apprentices have been gaining hands-on experience across all stages of the salmon lifecycle, achieving commercial vessel endorsements and developing long-term careers in aquaculture. 

“Mowi operates in some very remote and often fragile communities across the Western Isles, and it’s vital that we have committed and passionate staff at our farms,” Ben Hadfield, Mowi’s chief operating officer farming Scotland, told The Scoop. “I’d like to extend my heartfelt thanks to everyone who has worked so hard to get Stulaigh South up and running.

“This new farm has been developed with fish health and welfare at front of mind, and we also hope it will play a key part in local employment and community development, helping to strengthen the local economy of the Outer Hebrides.”