Report on Red Skin Disease from the Environment Agency’s National Fisheries Laboratory and NRW
Current knowledge and guidance
Red Skin Disease
In recent years there have been reports of small numbers of wild salmon caught in Scandinavia, Ireland and parts of the UK with signs of ventral haemorrhaging. We are monitoring the situation on all our major salmon rivers and working with partners to better understand the cause. Please report any similar sightings, or fish in distress to the Environment Agency or NRW immediately using the details below.
Marked ventral haemorrhaging in a wild Atlantic salmon associated with RSD
Initial reports
Low level mortalities of wild Atlantic salmon exhibiting unusual ventral skin lesions have been reported in rivers draining into the Baltic Sea and Northern Atlantic in the last few years. Cases were first reported in the UK from Scotland in summer 2019. This condition, termed Red Skin Disease, has prompted efforts to monitor its occurrence, confirm exact characteristics of the skin lesions and identify the cause.
What does it look like?
From reports so far, the most consistent characteristic of the condition appears to be severe ventral haemorrhaging in fresh run Atlantic salmon. This can appear like a spotted red rash (petechia) running along the underside of affected fish. These lesions may become ulcerated and vary in appearance due to secondary infections. Affected fish have mainly been seen during the warmer summer months.
What is the cause?
The cause of this condition is currently unknown. Detailed characteristics of the condition also remain unclear. There is a need to establish more reliable descriptions to support consistent reporting and enable comparisons to be made between countries. Identifying the cause of any skin condition in wild salmonids can be challenging due to the role of common opportunistic infections that can complicate or mask underlying changes.
What is the impact of this condition?
The importance of this condition is also unknown. So far, only small numbers of salmon have been affected and it is unclear what impact these lesions have on fish health. Low level lethargy and mortality have been reported in some rivers, although affected fish may also appear in good health and it is thought that these fish can recover.
Observations in England and Wales
There have been a number of visual reports of suspected RSD of varying severities in wild salmon from rivers in England and Wales. Staff operating index monitoring traps have also seen mild red patches on the underside of healthy salmon returning to our rivers for many years, but these are less severe than other recently reported cases, and have not been associated with any losses or evidence of ill-health. Work is underway to establish whether these skin lesions are in any way connected to reports elsewhere.
Mild ventral haemorrhaging observed on Atlantic salmon in England
What we are doing
We are in contact with partners across Europe to better understand this condition and share observations. We continue to monitor disease in all of our major salmonid rivers and are working closely with colleagues in Natural Resources Wales to monitor and collate reports. Investigations are ongoing through staff at our National Fisheries Laboratory to try to understand more about this condition.
To increase awareness and promote reporting of RSD, we have produced a number of guidance documents, including a recent updated briefing note on RSD which can be found on the Institute of Fisheries Management (IFM) website at: https://ifm.org.uk/ifm-training/ifm-fishery-guidance/
What you should do
We are asking anyone who encounters fish that are diseased or in distress to contact our incident hotline immediately. This will allow us to respond promptly to any serious or emerging disease incidents. We also ask for anglers to be vigilant but not to remove or handle any fish in distress. Photographing fish with signs of abnormality can be extremely useful if the situation allows and it is safe to do so. However, any fish caught by rod and line showing signs of disease should be returned to the water as quickly as possible.
We encourage anglers to practice good biosecurity and disinfect their waders, boots, nets and wet equipment after fishing and before moving to other waters. This can be done by thorough drying in sunlight or with the use of appropriate disinfectants.
To report dead or dying fish, please contact the Environment Agency’s hotline immediately: 0800 80 70 60. For further information please contact the Environment Agency’s National Fisheries Laboratory Tel: 02084 745244 or 07825 111723, E-mail:
As an Alliance of five organisations, we will build on the existing work of our partners and maximise our impact by taking a coordinated approach and vital action in order to halt and reverse the decline of wild Atlantic salmon.
The goal of the Missing Salmon Alliance is to build an evidence-base to influence national and international decision-makers to regulate activities that adversely impact wild Atlantic salmon.
The Missing Salmon Alliance
The MSA is comprised of the following members:
Game & Wildlife Conservation Trust, Atlantic Salmon Trust, the Angling Trust with Fish Legal, The Rivers Trust and Fisheries Management Scotland.
https://www.missingsalmonalliance.org