Salmon welfare is affected by a number of factors such as nutrition, social conditions, handling, transportation and disease. Aquaculture sites are legally liable to ensure that they are operated in a way that promotes fish health. Site managers, salmon farmers, personnel at fish processing sites and transport staff have to demonstrate their theoretical and practical knowledge of fish welfare. They should also take part in training every five years. The Norwegian Food Safety Authority is responsible for making sure that companies have sufficient expertise on the subject. Currently, a great deal of research and development is being carried out, for example on new technologies and management methods that can optimize fish health.
Water quality is important for fish health. Aquaculture sites should be designed and maintained so that water flows freely through the cage. Oxygen saturation, temperature and salinity are checked regularly to ensure good water quality. Sites are also required to have a backup system that protects the salmon's basic needs in the event of system failure. The Norwegian Institute for Water Research (NIVA) deals with research, development, documentation and consultancy related to fish health in aquaculture.
Specially designed aquaculture sites
Salmon sites must be large enough for the fish to swim and behave as naturally as possible. Cages should be suitable for local conditions and climate. The regulations state that a cage should contain 97.5 percent water to give the salmon good growth and living conditions. Sharp edges and materials that may harm the fish are prohibited. The cages should also be designed to give the fish the best possible protection against attacks from other animals. In 2004, the NYTEK regulations were introduced to prevent fish from escaping. These regulations contain technical standard requirements for floating fish sites. The sites also need an approved facility certificate.
Operation of aquaculture sites
The fish, installations and production units should be inspected daily. The inspection should interfere with the fish as little as possible, and immediate action should be taken if the salmon display abnormal behaviour. Staff should carry out additional checks before and after a storm. Alarms at the facilities should be inspected at least once a week. All aquaculture sites have a biennial operational plan that is evaluated by the Directorate of Fisheries and the Norwegian Food Safety Authority. The plan should include an emergency plan to ensure that infection control and fish welfare are upheld in a crisis.
Salmon feed should be nutritious and promote fish welfare. The feed should be adapted according to the fish’s age, stage of development, weight, physiology and behaviour. When salmon reach a certain size, they are fed daily. The feed is distributed so that the fish have a steady supply of food, without being overfed. Read more about the ingredients in salmon feed here.
Infection control and hygiene
Good infection control and hygiene are essential for salmon welfare. Aquaculture sites must follow a number of steps to ensure adequate infection control. They should be inspected at least six times per year and visited by a fish health biologist twice a year. Sites should also be fallowed regularly to reduce the risk of infection. After each production cycle, the site should be fallowed for at least two months, to avoid any diseases spreading. If required, fallowing can be carried out by the Norwegian Food Safety Authority. It is also important to keep installations and production units clean, and to ensure that staff, work clothing or equipment do not spread infection.