Aquaculture is a modern industry which is constantly developing and innovating. In this section we answer some of the most frequently asked questions about salmon farming
- Identification of an area where the sea conditions are suitable to safely grow salmon and ensure minimal impacts on the marine environment, other sea users and the landscape / seascape.
- Public bodies, marine stakeholders and local community are invited to comment on the proposed site location and design.
- Consultation feedback is used by the developer to decide if the project should proceed and to refine the proposal if required.
- Details of the proposed development are sent to the Local Planning Authority (LPA) and a screening/scoping opinion requested.
- Advised by statutory consultees, the LPA advises if the developer needs to submit an Environmental Impact Assessment (EIA) with the planning application and what environmental, heritage, social (human) and economic receptors the impact assessment must consider.
- The developer submits a planning application, together with an EIA if required, to the LPA.
- All documents can be viewed on the planning portal. The proposed development is advertised in a local newspaper and open for public consultation for 28 days (if EIA submitted). The documents are also reviewed by statutory consultees to the planning process.
- After the consultation period, the LPA determines whether to grant or refuse planning permission, based on the likely significant effects of the development (positive or negative) on the environmental, heritage, social / economic receptors.
Marine fish farms are required to obtain all of the following consents before they can be developed and stocked with fish:
- Planning permission from the relevant Local Planning Authority (LPA). To develop a new fish farm, or modify an existing fish farm, planning permission is required from the relevant local council. The council decide whether to grant or deny planning permission based on the likely effects (positive and/or negative) of the proposed development, usually based on a detailed Environmental Impact Assessment.
- A licence controlling discharges to the water environment from the Scottish Environmental Protection Agency (SEPA) under the Water Environment (Controlled Activities) (Scotland) Regulations. The SEPA licence regulates the impacts of fish farming on the seabed and water column through setting limits on the amount of particulate waste (fish waste and uneaten feed) and medicine residues that can be released into the sea.
- A marine licence from Marine Scotland as marine fish farming is a licensable activity under the Marine Scotland Act 2010. The marine licence is primarily concerned with the location of the fish farm infrastructure (e.g. moorings), any potential hazards these may pose to navigation for other sea users and how these will be mitigated.
- Authorisation to operate as an Aquaculture Production Business from Marine Scotland Fish Health Inspectorate, prior to farming activities commencing. The authorization requires us to meet standard conditions including keeping records of stock movements and mortalities and implementing risk-based surveillance schemes and good hygiene (biosecurity) practice;and
- A seabed lease from Crown Estate Scotland, which manages virtually all of the seabed out to 12 nautical miles.
Planning permission from the LPA is usually the first consent applied for. The planning application process is illustrated above, and highlights where the public, other recreational and commercial users of the sea and regulatory bodies can input to the process.
Salmon farming results in the emission of waste particles, comprising fish faeces and uneaten food, which ultimately sink to the seabed. The amount of particulate waste produced depends on the number of fish being farmed and the amount of feed used. The area over which the waste is deposited (the footprint) depends on the physical characteristics (i.e. currents, waves and water depth) of the site.
The particulate waste, which is rich in carbon, can result in a build-up of nutrients on the seabed (organic enrichment) leading to a deterioration in the physical and chemical properties of the seabed and changes in the associated animal communities. This impact is regulated by SEPA under the Water Environment (Controlled Activities) (Scotland) Regulations.
The regulations are designed to ensure that the extent of seabed affected is restricted to a defined area (the mixing zone which extends 100 m from the edge of the pens in all directions) and that the volume of waste deposited does not exceed the capacity of the seabed communities to assimilate (recycle) the nutrients within that area. This is achieved through SEPA setting Environmental Quality Standards (EQS), relating to the condition of the invertebrate communities, both within and beyond the mixing zone. In this way, SEPA limit the magnitude and the scale of the impact of fish farming on the seabed. During each farming cycle, Cooke are responsible for monitoring the seabed within and beyond the mixing zone to ensure these limits are met.
It is a health and welfare requirement for fish farms to have a range of measures to treat fish for disease or parasites (e.g. sea lice) if there is an outbreak at the farm site. This is also important for the protection of natural heritage features in the marine environment, such as wild salmon and trout. Although fish parasites and disease pathogens occur naturally in the marine environment and hence in wild fish populations, the ability to be able to treat any occurrence in our farmed fish, reduces the potential risk of transmission to wild fish.
Cooke seeks to avoid the use of medicinal treatments whenever possible to minimise our impacts on the marine environment. Non-medicinal treatments that have proven effective for fish health issues and removed the requirement for further medicinal intervention include:
- Freshwater treatments (within a specialised boat referred to as a well boat) for sea lice and gill disease
- Physical removal of sealice by a Hydrolicer or Thermolicer system
If medicinal treatments for disease or sea lice should be required, this can be administered via:
- A bath treatment, in a tarpaulin enclosure within the pen or within a well boat. Once the treatment is complete, the water and any residual treatment agent is released into the sea.
- Within the salmon feed – with residual medicine being excreted within the fish waste.
The types and quantities of treatments that can be used at fish farm sites in Scotland is regulated by SEPA via the Water Environment (Controlled Activities) (Scotland) Regulations. These regulations restrict the concentration of treatments that can be used and the rate at which they can subsequently be discharged, to ensure that the residual concentration entering the marine environment meets the environmental quality standard (EQS) for each type of treatment. The EQS are the safe concentrations which have been set to be protective of all species in the marine environment.
The sea lice treatments currently licensed for use in Scotland are cypermethrin, deltamethrin, and azamethiphos (for bath treatments) and emamectin benzoate (slice) in-feed treatment. Cooke must apply for a CAR licence to be able to use any of these treatments at a specific farm site. Notice of the requirement to use these medicinal treatments must be given to SEPA before they are administered. Information about the treatments that have been used on any fish farm site in Scotland is publicly available on Scotland’s environment web.
Our fish farms comprise pen nets, which contain the fish in the water and contribute to stopping seal predation, and top nets over the pens, designed to prevent aerial predation and ingress to salmon cages by birds and otters. We can also deploy secondary, external predator nets which surround pen nets and provide an additional level of protection against seal attacks.
The risk of wildlife entanglement varies depending on the species, mesh size, and nature of netting systems. Cooke implement a range of measures to reduce interactions between predators, which in turn reduces the risk of entanglement or entrapment. These measures include:
- Pen nets are constructed with twine, which is strengthened with marine grade stainless steel, and the pens are weighted so that the nets are tensioned (taut) under water. These have been proven effective at reducing seal interactions at production sites.
- The mesh size of the top nets is less than 100 mm. This is based on guidance from NatureScot (the Scottish Government’s statutory nature conservation advisor) that ceiling mesh sizes greater than 100 mm have the potential to cause entanglement or entrapment of diving bird species, particularly gannets.
- External predator nets consist of 50 mm brightly coloured mesh to prevent the entrapment of any diving wildlife. Any such nets would be tensioned and maintained throughout use to prevent any entanglement risk.
- Daily wildlife entanglement/entrapment monitoring is undertaken at all production sites. Entanglement and entrapment events are reported to NatureScot biannually which allows the effectiveness of our predator control measures to be reviewed and new measures to be adapted if required (referred to as adaptive management).
Northeast Nutrition Scotland Ltd (a subsidiary of Cooke Aquaculture Inc.), produces all of the aquafeed for Cooke Aquaculture Scotland’s seawater farm sites. Aquafeed is made of several ingredients of marine and plant origins, such as fish meals, fish oils, vegetable oils (e.g. sunflower, rapeseed), wheat, vitamins, minerals and pigments. Plant based ingredients now form the highest proportion of our aquafeed diets.
Historically the two most important ingredients in salmon feed have been fishmeal and fish oil. The inclusion of these high quality marine ingredients in the feed leads to higher nutritional efficiency (conversion of ingested food to biomass), survivability, growth, quality and, most importantly, improved health and welfare of our farmed fish. All marine ingredients used are sourced from sustainably managed fisheries certified by either the MarinTrust or the Marine Stewardship Council (MSC). This minimises any impacts of including these marine ingredients, for example, on marine biodiversity.
The vegetable ingredients in salmon feed are derived from plants like sunflowers, rapeseed, maize, broad beans, wheat and soy. Suppliers of these ingredients must comply with Cooke’s sourcing policy which includes traceability and certification regarding non-Genetically Modified Organisms (GMO) and origin from deforestation-free areas. Cooke has sought to substitute some vegetable ingredients with more sustainable ones to minimise the potential impacts of feed production on the environment and biodiversity. For example, no palm oil or soy protein concentrate were used in aquafeed produced by Northeast Nutrition Scotland Ltd during 2021.