Farmers can reduce this by the use of freshwater treatments in wellboats © Scottish Sea Farms
The site, which is located at Billy Baa, in Shetland, is due to come onstream in May and will have nine 160 m pens and one of 120 m.
Richard Darbyshire, the company’s regional manager for Shetland, said the average depth is 45m, making it one of the deepest farms in the archipelago.
“With the depths at Billy Baa and the new 160m pens, our fish will have more room than ever to grow,” he told company newsletter, The Source.
“These larger pens in larger grids improve the water flow through the farm and lead to better performance and survival.”
The new farm represents a total investment of £7.5 million, with the majority of the spend with Scottish suppliers. The £1.8 million workboat is being built by MacDuff Ship Design and the pens and moorings are from Inverness-based Gael Force Marine. The SeaQurePen 500s are built to withstand the challenging environment in Shetland and, according to SSF, will be a much improved working platform for the farm staff .
A tried and tested double netting system has also been installed, with a 75mm mesh outer net and an 18mm mesh inner net, as well as a new “glider” system for the nets to ensure correct tension throughout. ScaleAQ in Scotland supplied the cameras and 500-tonne steel feed barge, which is not just Scottish Sea Farms’ largest barge to date but also equipped with its most advanced hybrid system.
“We are installing a Fjord Marine Hybrid system from Fjord Maritime, to power the feed barge,’ said Derbyshire. “We trialled the technology on one of our existing farms and made fuel and maintenance savings worth £250,000, so have decided to increase the size to give even greater savings and reliability.
“We will also be using the latest ultra high-definition feed cameras, along with a new motorised feed spreader that will reduce power consumption and increase feed spread and availability.
“The sector is constantly evolving and our aim is to reduce the carbon footprint of the salmon we produce even further.”
Combining scale with sustainability also provides farmers with the most reliable systems to safeguard fish health and welfare. As Robbie Coutts, SSF’s area manager for West Shetland, explained: “There will always be environmental challenges so we are continually looking to new technologies to enhance fish health and survival.
“We have just had the warmest ever seawater temperatures on our Shetland farms, with several weeks in the height of summer 1.5°C warmer than the seasonal norm. This helps with fish growth, but leads to issues with water quality, oxygen levels and the speed of AGD progression.
‘We have a sophisticated water quality analysis lab in Lerwick, and we’ve implemented a daily water quality monitoring protocol on every Shetland site, with a traffic light system to warn the farms of high plankton and micro jellyfish numbers when detected.
“Improved aeration technologies allow us to draw to the surface colder deep water, which has more oxygen availability and less potentially harmful algae and jellyfish, during these events. ‘We have also invested in increased wellboat capacity to perform freshwater reverse osmosis treatments for AGD and sea lice, with 2500m3 and 2200m3 vessels that operate in Shetland. And in the past 12 months, we have added FLS delousing capability to these wellboats.”
Future goals include increasing the smolt transfer size from the current 130 g to shorten the production cycle in marine pens and reduce the amount of fish handling events. In the pipeline for 2026 and beyond is moving further offshore to locations that are even deeper and have improved tidal flow.
“We have identified some potential sites that show promise, including Fish Holm in the Setterness area, an existing farm which we are looking to expand,” said Darbyshire. ‘The hydrodynamics are extremely favourable and are very similar to the strongly flushed farms in Orkney that have produced solid farming results.”
