Fish health


Fish health is vital to ensure sustainable exploitation of resources. Good fish health implies that the highest possible number of fish does well, grows normally and survives throughout the life cycle. It is an important duty for fish farmers to work systematically with fish health through preventive measures, so that the fish gets the best conditions to stay healthy. High mortality has a major negative impact on profitability. It is likewise important that fish health considerations balance the use of medications, both in terms of resistance and impact on the local environment.


We pursue a systematic, long-term approach to achieve good growth and high harvesting quality. The foundation is made by ensuring good fish health. This includes the preparation of overall fish health plans for each region. The plans cover regionally adapted infection prevention and vaccine strategies, and should be adapted to each specific region. Fish health plans are revised upon need. For an optimal mutual response, we also focus on local cooperation and transparency towards other participants. When the fish are processed, we will preferentially opt for non-chemical treatments and take into account potential impact on the local environment.


We work every day to ensure that we keep the fish alive and healthy. Preventive fish health measures are essential to our success. These measures include our health feed programs which focus on increasing the fish robustness and ability to cope with stress and external influences, and thereby also reduce the need for medical treatments. Other preventive measures include a.o. site visitation orders, use of disinfectants and disinfectant footbaths, routines for removal of dead fish and offsite storage. As an example, we isolate installations by prohibiting transfers between facilities unless the boat is disinfected. We deploy PCR screening for early detection of any parasites, viruses or bacteria.

Another important preventive measure is the establishment of management agreements to maintain best practice in collaboration with other actors in the same area, and by this reduce risk of contamination in the area.

We systematically monitor the health situation at all our locations. We do weekly reporting on indicators such as mortality, and daily digital reports are available to regional managements. In order to compare our results for mortality with other sector players, mortality is reported in accordance with the performance indicator GSI has defined for mortality. Another important part of the monitoring job is the statutory fish health inspections at all locations. This includes monthly reporting on fish health, which includes records of external injuries, potential diagnoses and mortality. Monitoring is also adapted to the specific regions. For instance in Rogaland we collect gill scores for detection of AGD twice each week in exposed periods.

Chart 1 shows an overview of the mortality rate of all our regions. The indicator is reported according to GSI. Grieg Seafood aims for less than 7% mortality. In 2016, we achieved this goal for Finnmark, and we were very close in Rogaland. It is the first time Finnmark has been registered to meet the goal, which is a result of systematic efforts to reduce mortality among smolts. In Shetland, there has been an unfortunate raise in mortality to 17%. The primary cause is deteriorated gills condition which has weakened the fish´ tolerance to different methods of treatment. In BC, we experienced a positive development from a level of around 14% mortality in 2015 to 10% in 2016. The mortality we had in BC, is mainly due to low oxygen levels, as well as outbreaks of SRS disease in one area and Furunculosis in another area.

The causes of death in the other locations are mainly related to gill damages from algal blooms in Shetland, the PD disease in Rogaland, and some Yersinia ruckeri and Tenacibaculum outbreaks in Finnmark.

Some of the measures to fight disease and promote fish health do however involve medical treatment. Chart 2 shows an overview of regional use of antibiotics. Although we aim to avoid the use of antibiotics, there are some diseases that must be treated this way, partly due to the welfare of the fish. In 2016, the consumption of antibiotics remained low in all regions, except in BC. The consumption was somewhat lower in 2016 than the previous year, but still higher than desirable. The need for antibiotics in BC is largely induced by the diseases Tenacibaculosis, Piscirickettsiosis and Furunculosis. In Shetland, one group of fish received treatment against bruises, with a good outcome. Throughout 2016, Rogaland and Finnmark have not received any treatment with antibiotics.

As part of our efforts to ensure good fish health and prevent loss of fish, it is necessary to protect fish against birds and marine mammals entering our facilities. We try to minimise the impact on wildlife as we carry out these measures. Despite our efforts, some wildlife can die as a result of interacting with our farms, either intentional or unintentional. In 2015, we started systematic reporting of the number of mammals that have been killed, with or without intention, as a result of interaction with our business, see Chart 3. As from July 2016, this reporting has been extended to include number of birds killed.

In BC, a total of 3 sea mammals was killed throughout 2016, while the regions had zero.

In total, 48 birds were killed during the last half of 2016, distributed over our regions. BC did not register any killed birds.


Our aim is to keep the average mortality rate for the Group below a maximum of 7%. In order to reach this goal we will make the necessary investments in sites with high mortality rates, and make sure to learn from internal and external best practices for keeping the fish alive. As a part of this work, fish health plans shall be prepared for each region. This is carried out by fish health responsible personnel in each region, to ensure optimal treatment and fish health with emphasis on responsible use of medicine. We aim to establish a technical team to discuss this topic across the regions, in addition to the current efforts done by the regional directors and their management.

Finnmark will continue its ongoing fish health project to reduce mortality in sea, through safe and good handling, and optimising smolt quality before release. In Shetland, we are well into the process of rescheduling production into an 18 month cycle, which will reduce the time in sea for the fish, and thereby improve survival rates and minimise the need for treatments. We will achieve this by releasing larger smolts into the sea and maximising growth.


*Mortality is defined as: Total number of mortalities in sea last 12 months – total number of culled fish due to illness or similar and not included in the harvested number)/(closing number of fish in sea the last month + total number of mortalities in sea the last 12 months + total number of harvested fish the last 12 months + total number of culled fish (due to illness or similar and not included in the harvested number)) X100