A new wellboat for Marine Harvest has been launched at Corpach pier, in a first for Scotland.
For it uses natural methods to eradicate sea lice and prevent a range of potential fish diseases by utilising reverse osmosis technology
The vessel, 70m long, with a 2,000 cubic metre capacity was officially named Inter Caledonia by Eli Toraasen, who is now designated the ship’s “Godmother”, in a ceremony watched by representatives from the local community, suppliers and staff. Following the naming ceremony there was an “Open Boat” when people had a chance to go on board and see the vessel’s equipment and on board facilities.
As well as removing and destroying sea lice, the new vessel uses the fresh water to prevent the development of fish Amoebic Gill Disease (AGD), which can occur when water temperatures are higher than normal.
The wellboat has the capacity to carry up to 300 tonnes of live fish at any one time. She will use reverse osmosis technology to turn seawater into fresh water at a capacity of 200M3/hour, and will be able to completely fill her wells every ten hours, allowing the fish to be bathed in fresh water.
As Ben Hadfield, MD of Marine Harvest Scotland explained: “This is a major step forward for Marine Harvest and part of our drive to deliver an efficient and sustainable industry. The industry has used wellboats before for this purpose but they have always had to pump the fresh water on to the boat, this is the first that combines the entire operation within the vessel.
“Many of the challenges we face as salmon farmers are naturally occurring, such as sea lice or Amoebic Gill Disease. This will provide a natural solution for these problems, as freshwater prevents the development of AGD and also allows us to remove and then destroy sea lice.
“It’s a great new tool for us and we’re sure it will reap rewards for us by helping us maintain our fish in peak condition.”
The vessel will be able to treat 24/7, as a result of the desalination which will continuously exchange water at the rate of 200 cubic metres every hour.
Havard Grontvedt, Chairman of Intership AS, owners of the wellboat which will be leased to Marine Harvest Scotland said:
“We expect to set a new standard within the wellboat industry with Inter Caledonia, specially when it comes to fish density, gentle fish handling and hygiene.
“With the freshwater production plant the vessel will be a very efficient and environmentally friendly tool for the treatment of sea lice and AGD.
Inter Caledonia will be used to treat the fish on all the company’s salmon farms across the west coast of the Highlands and Western Isles.
In 2012 a number of Scottish salmon farms lost fish due to problems with Amoebic Gill Disease, a naturally occurring amoeba. The unusually hot and dry weather then led to higher sea temperatures and, more importantly, higher levels of salinity.
Outbreaks of AGD occur all over the world, although it’s mainly a problem in Tasmania. The amoeba occurs naturally in the environment but usually at very low levels that don’t cause an issue.
Marine Harvest has adopted a range of different measures to address the challenge of sea lice and have placed an emphasis on developing natural solutions. As well as the use of fresh water in the wellboat, they are also growing wrasse for use on their farms. Wrasse, also known as cleaner fish, are natural predators of sea lice.