Protect our oceans

Fish health and fish welfare

For the Group, fish welfare involves protecting fish against unnecessary stress and impact.


Our fish welfare initiatives are comprehensive and  cover every part of our farming value chain.

Mandatory fish welfare training for all staff comprise legislation, animal welfare, fish health biology, stress, sedation and euthanasia. Other topics covered are natural behavior, environmental requirements, water quality and physiology. Based on this knowledge, staff are also trained in internal fish handling protocols/handling policies.

Welfare indicators are used throughout the production cycle. At harvest stations, welfare  indicators are used prior to, and after stunning and bleeding. All of our harvest stations use either electrical or mechanical stunning approved by the Norwegian Food Authorities. Indicators such as eye reflex and operculum movements are monitored continuously and recorded daily to ensure fish welfare.

During transportation of fish in well boats, there is implemented a risk based water quality monitoring and control program. This continous monitoring includes parameters such as temperature, dissolved oxygen and pH. Limits are set according to duration of transport, density in tanks and size of the fish.

What measures do we take to handle the fish as gently as possible?

We use procedures as management tools for our production. The procedures help us to standardize events at each life stage, and they are updated as soon as we gain new crucial knowledge regarding fish welfare. In this way, the entire organization acquires the new knowledge quickly and efficiently.


Pumps, transportation pipes, sorting equipment and vaccination equipment are checked at regular intervals and any damage or defects are repaired before use.

During major operations such as vaccination and sorting, the fish is checked for any damage at regular intervals to detect defects in the equipment.

All components used during sea transfer are checked regularly. If situations arise where an increased incidence of mechanically inflicted damage is registered, delivery is stopped until the cause of the damage has been investigated and corrected.

Ongrowing stages:

During sea transfer, dead fish are controlled for mechanical damage that may have been inflicted in connection with the transport. If it turns out that there is presence of mechanically inflicted wounds, a review of the delivery process will be taken.

When fish are crowded during various forms of handling, we have our own handling policies describing how this is to be carried out to ensure fish welfare.

In all non-medical lice treatments, welfare screening of the fish is performed before and after it has been treated. In this way, we have documentation of the impacts for the fish, and whether measures may need to be taken to reduce the negative consequences or not.

Cleaner fish

The company produces around 10 million Lump sucker per year. This implies a high ratio of self-supply, which in turn ensures predictability for deliveries and enables us to control targeted improvement measures, aiming to ensure predictability and biological  improvements for production.

Welfare for cleaner fish has been debated for some time, and we acknowledge the challenges involved in farming  cleaner fish. At the same time, we are aware that our  measures are moving us in the right direction, biologically. Our onshore production facilities have implemented improvement measures within operations  and biosafety, providing significant improvements to biology and cleaner fish welfare.

These measures encompass a wide range and comprise of:

  • Screening and selection of parent fish
  • Value chain regionalisation
  • Providing optimal environmental conditions
  • Providing optimal nutritional values
  • Improvements within logistics and handling
  • General biosafety measures such as input water disinfection, hygiene zones in time and space
  • Production biology

After transfer to salmon production sites, when the cleaner fish perform their function by eating salmon lice, we continue to experience challenges. The causes  of terminal losses are dominated by bacterial disease. 

Measures to improve welfare are:

  • Production planning and release strategy
  • Farming and keeping cleaner fish
  • Feeding strategy
  • Catching escapees and separation
  • All cleaner fish has access to tailor made kelp forests to support natural behaviour, which are adapted to each species and need for resting places.
  • Vaccination

The cleaner fish have the same requirements for  health. This is performed by authorised animal health personnel. Lump sucker are fed with special adapted  feed and harvested in the same way as salmon and rainbow trout.

Main goal:  Work for a better survival rate after transfer  to salmon production sites.

Main goal:  No disease and good fish welfare


Policy: Fish health and fish welfare

KPI: Fish health and fish welfare

Zone cooperation 100%

All of our on-growing sites take part in a zone - based cooperation with other farmers. In all regions where the Group has operations, fallowing, washing/disinfection and restocking are coordinated in zones every second year. This cooperation also involves coordination of operations, collaboration relating to lice, disease management and other issues where the solution to the problem requires a joint, coordinated effort.

R&D Projects within Fish welfare and farming

The group participates in many different research projects in order to be at the forefront in terms of the best possible fish health and to implement new technology and expertise as soon as possible.

The various projects can be roughly divided into 3 different areas:

  • Sea lice
  • Medication
  • Survival

Most of our ongoing projects will fall into one of these groups.

Disease management

Disease management is of essential importance for all animal farming. Within the Group, disease  management is based on a preventive operational practice, where the primary goal is to prevent problems before they occur.

Our work on disease management is based on  recognized principles. These are in turn based on  biological know-how and attitudes, in which training for our employees and a live internal control system lay the foundations for operations.  Disease prevention and management are monitored by authorized animal health personnel, who also play key roles related to Lerøy's continuous learning  and development of best operational practice.

We aim to farm fish with production conditions that safeguard the biological requirements of all species. Density and water quality parameters, such as temperature, salinity and oxygen shall be adapted to the requirements for fish at different life stages. We have a specific vaccination program and vaccinate 100 % of our fish before sea transfer.

The main target for fish health and welfare is to increase fish survival rates from sea transfer to slaughter. All employees involved in fish farming take part in training focusing on fish welfare.

Fish welfare is developed and monitored by keeping use of  medicines to a minimum, with careful assessment of use, using only approved medicines which have  documented environmental impact in accordance with the  requirements of The Norwegian Medicines Agency, monitoring and documenting tolerance, and  following up biological feed factors.

Use of medication

Medication is used only when this is deemed appropriate and necessary.

We exclusively make use of licensed products, and all medicine prescriptions are issued by authorized animal health personnel. Lerøy Seafood Group currently has between 20 and 30 persons employed as authorized animal health personnel.

Chemical used in delousing agents, active agent

Year  Via feed (kg) Via bath (kg) Hydrogen peroxide* (kg)
2013 0.00006 0.002321 4.35
2014 0.002474 0.003034 40.87
2015 0.00132 0.001361 50.45
2016 0.00160 0.000547 18.40
2017 0.000162 0.000076 1.83
2018 0.000023 0.000003 6.11
2019 0.000149 0.000030 2.50
2020 0.0001 0.00012 5.3



Policy:  Use of medication