Nicki olmyard
How realistic are ambitions to turn Scotland – and the rest of the UK – into a producer of warm water species through land-based aquaculture?
In the run up to Sco�sh parliamentary elec�ons on 6 May it was never seriously in doubt that we would see the SNP con�nuing at the helm in olyrood, whether as a ma ority party or as the dominant partner in a coali�on. There is no ques�on that the SNP supports aquaculture; it is clearly stated in the party’s manifesto: “Fish farming is something that Scotland is well placed to do well in, but it must grow sustainably, in harmony with the marine environment that supports it.”
There is also a pledge of support for innova�on in aquaculture, including the development of closed containment fish produc�on on land, and exploring “the poten�al to produce more shellfish in warm-water, land-based farms, to cut the amount of unsustainably produced fish and shellfish being imported into Scotland.”
These pledges build on the Aquaculture 2030 Strategy, published by Scotland Food and Drink a few years ago. This sets out a vision for aquaculture growth in Scotland, and iden�fies key ac�ons required to double the economic contribu�on of the industry from £1.8bn in 2016, to £3.6bn by 2030.
Included in the strategy is the need for greater research, development and innova�on (RD&I) in Scotland, to address the challenges faced by the aquaculture industry, such as climate change. Investment is called for to support growth and reflect the industry’s priori�es, which include a shi� to new produc�on models using exposed sites and on-shore ‘super-smolt’ facili�es.
While the Sco�sh Aquaculture Strategy makes no specific men�on of warm water species, the nglish Aquaculture Strategy states: “Although current produc�on levels are very small, aquaculture is capable of producing warm-water species and other exo�c species such as �lapia and shrimp that are currently imported. This has the poten�al to grow, especially given changes in the trades and markets following the U- xit and ID-1 .” , by Professor K. lack and Dr A. ughes ( uly 2017), is a review commissioned as part of the UK government’s Foresight Future of the Sea pro ect. It acknowledges that aquaculture has grown in the last 40 years to be an important component of the UK seafood sector, with a produc�on value in excess of £5 0m to the UK economy, and that strong government support for the Sco�sh aquaculture industry has contributed to its growth and ongoing plans for expansion up to 2030.
The authors iden�fy climate change, energy prices, government policy and social acceptance of aquaculture as key components in shaping how aquaculture develops in the next 50 years, and state: “There is significant poten�al for aquaculture to further develop across the UK, especially in semi-contained recircula�ng aquaculture systems (RAS) on both land and sea, and in offshore cage aquaculture.”
The report introduces four development scenarios, and points out that because energy costs impact every aspect of the value chain, future fluctua�ons are likely to have a very large influence on the way that aquaculture develops. As such, scenarios with a higher rela�ve energy cost, reflect higher feed, transporta�on, infrastructure and fabrica�on costs.
“In broad terms it can be supposed that if rela�ve energy prices reduce, then those aquaculture produc�on systems which are energy intensive will become more economically viable and vice versa. RAS are highly energy-dependent.
For fish species that rely on feed like salmon, recirculation aquaculture will become more economically competitive in a cheaper energy world. Due to its environmental advantages, if energy becomes sufficiently cheap, then it is expected that RAS will rapidly increase.”
The report also points out that expansion in RAS combined with cheaper energy costs would lead to a growth in the number of species cultured, with attendant development of high-value niche markets, probably based on warm-water exotic species such as shrimp.
The UK currently produces a narrow range of aquaculture species, dominated by salmon, rainbow trout, mussels and oysters, but also including small volumes of Arctic charr and sturgeon, and increasing production of wrasse and lumpfish, which are bred for use in fish farms, to remove sea lice from salmon.
The English Aquaculture Strategy predicts that small quantities of freshwater and saltwater exotic finfish and shellfish will gradually be introduced over the next 20 years, as production techniques improve. However, the question remains as to whether it will be economically feasible or environmentally attractive to produce them. To date, all attempts to grow exotic species such as barramundi and tilapia in the UK have failed to turn into viable commercial ventures, although there are a handful of micro-business aquaponic tilapia farms.
Three-Sixty Aquaculture, based in Swansea Docks, now has advanced plans to turn its former wrasse production unit into a farm for sablefish (black cod), which are native to the Pacific.
“Being a cold water species, the conditions here should be ideal for sablefish, and top chefs are excited by the prospect of having it grown in the UK, instead of importing from Canada,” said technical director Lee Tanner. The tropical shrimp species , also known as the whiteleg shrimp or King prawn, is also a prime candidate for land-based production. UK consumers love eating prawns, and retail sales of all cold water and warm water prawns top 40,000 tonnes per year, with a value of more than £500m. A similar volume is sold through foodservice. Producing in the UK makes sense in terms of reducing the product’s air miles compared with importing them from far-flung countries such as Thailand, Vietnam, Ecuador and Brazil, but there is a downside in that energy is required to heat the water to around 30oC for production.
Disease has been one of the biggest challenges facing the global shrimp industry, with production almost wiped out in some years. It has also played a factor, along with Covid-19, in stopping production at two UK-based prawn producers over the past year, despite both companies changing their marketing strategies to target consumers direct.
Great British Prawns (GBP) in Stirlingshire, Scotland, which used a clearwater filtration approach for its production. FloGro Fresh in Lincolnshire, England grew its prawns in a biofloc system, using bacteria, algae and other organisms to clean the water and provide food. Both companies were hailed as innovators and their products lauded by top chefs, but neither is currently operating.
A Norwegian business aims to show the way, with a collaboration between Benchmark Genetics and the Happy Prawn Company, to raise post-larvae (PLs) imported from Florida. The shrimp are SPR, or specific pathogen resistant, with a documented high resistance to specific disease-causing viruses and bacteria, and are also certified as SPF, or specific pathogen free. Production is going well and there are already plans to scale up in a new production facility that will use surplus heat from dairy plant. Success for this venture might encourage imitators in the UK.
“If relative energy prices reduce… aquaculture production systems which are energy intensive will become more viable” economically