King scallop

Farmed scallops are filter feeders and do not require any commercial feed sources, as they get all their nutrient requirements from the surrounding water.

Suspended scallop cultures and bottom scallop cultures have minimal impacts on the environment.Overall, scallop aquaculture in Scotland performs well on environmental impacts. Scallops used in aquaculture can be found naturally in the marine environment. They live on sand or gravel sea beds, therefore culture is entirely sea-based. Habitat concerns resulting from the physical infrastructure associated with suspended scallop culture and hand harvesting are minimal. For bottom culture methods, dredging has the potential to have significant habitat impacts. However, tows for farmed scallops are generally much shorter than for wild-caught and farming takes place in shallow coastal areas which can recover from major disturbances within a few weeks or months. A variety of shellfish predators exist among scallop farms, including echinoderms, gastropods, crustaceans, fishes, and seabirds. Methods used to cultivate and harvest scallops in suspended rope generally do not result in direct impacts to predators. Scallop harvesting by dredge can result in an immediate decline in abundance and biomass of all species, but the decline is often followed by rapid benthic recovery. Passive and benign barrier yields are used to prohibit predators and are removed manually without lethal control.Scallop culture generally does not involve the application of chemicals (e.g. antibiotics, pesticides, herbicides, fertilizers) to control fouling and predators or to prevent disease. The amount of chemicals used in scallop culture is thought to be nominal, if at all. In addition, the water in which chemicals would be used is generally not released into the marine environment and therefore, there is no threat of chemical contamination to adjacent waters or organisms. As farmed scallops are not provided external feed and there is no nutrient fertilisation, there is no concern about the impact of effluents. However, there can be a concern over changes in the sedimentary environment due to bio deposition and sediment trapping. These changes are limited to the farm site and are not considered to extend beyond the immediate vicinity if the farm. Furthermore, scallop farming has been shown to increase water quality at the farm site through removal of excess nutrients and phytoplankton.Scallop juveniles or ‘spat’ used for farming are either collected from the wild or settle naturally on purpose-made collectors. At present, the cultivation of scallop relies on wild spatfalls which are usually of sufficient quantity and reliability. However, these are data gaps in the wild stock status of king scallops for the West of Scotland areas, as there is not a recent stock assessment. Therefore, overexploitation of these populations cannot be confirmed. Aquaculture systems that are open to the environment tend to pose a risk for disease and parasite interaction with wild populations. However, relatively few diseases have been reported in scallops and good management practices ensure that the risk is low. Disease outbreaks have not affected regional level populations.

Animal welfare is not applicable for shellfish as it is not covered by the assimilated EU regulations on welfare. Humane slaughter has been carried out by RSPCA definitions.

This assessment scores well for management measures but would benefit from third party certification.This assessment covers uncertified scallops produced in Scotland.Aquaculture policy in the UK is a devolved matter, with the separate administrations of Wales, England, Northern Ireland and Scotland responsible for its collective oversight. There is a total of 73 shellfish aquaculture sites in England and Wales, 55 in Northern Ireland and 328 in Scotland. In England, the Marine Management Organization has prepared marine plans for 11 predefined areas in England, covering 6 individual marine plans, all plans were in place as of June 2021. Aquaculture production in Scotland is covered in the 2015 National Marine Plan. Aquaculture production in Wales is covered by the Welsh Marine Plan which was released in November 2019. The Northern Ireland Marine Plan is currently still in development as of March 2024.In the UK, the regulations regarding the environmental impacts of aquaculture are either not applicable or are in place and are fully effective. These include the Conservation of Habitats and Species (Amendment) (EU Exit) Regulations 2019, which was transposed from the Habitats Directive 92/43/EEC and Birds Directive 2009/147/EC. This is the cornerstone of nature conservation policy and the protection of valuable habitats and species. There are also regulations in place to cover the use of land and water resources, discharges including effluents and their impacts, biosecurity and disease management.