Cleaner fish and caged salmon: EIR release

Information requested

1. What official advice has the Scottish Government published on the use of cleaner fish? In particular, how is the welfare of these fish to be safeguarded?

2. Cleaner fish have different requirements to salmon regarding living conditions. How can their particular needs be met when mixed with salmon in cages?

3. How many cleaner fish are used in salmon cages in Scotland?

4. What is the mortality rate of cleaner fish in salmon cages?

5. What are the causes of cleaner fish mortality in cages?

6. Annually, how many cleaner fish are culled by salmon producers in Scotland?

7. If no data is available to answer any of the above, what action does the government propose to take to ensure that such data is routinely recorded and published?

Response

As the information you have requested is 'environmental information' for the purposes of the Environmental Information (Scotland) Regulations 2004 (EIRs), we are required to deal with your request under those Regulations. We are applying the exemption at section 39(2) of the Freedom of Information (Scotland) Act 2002 (FOISA), so that we do not also have to deal with your request under FOISA.

This exemption is subject to the 'public interest test'. Therefore, taking account of all the circumstances of this case, we have considered if the public interest in disclosing the information outweighs the public interest in applying the exemption. We have found that, on balance, the public interest lies in favour of upholding the exemption, because there is no public interest in dealing with the same request under two different regimes. This is essentially a technical point and has no material effect on the outcome of your request.

Please note that questions 2 and 7 of your request will be handled out with the EIRs because they are not strict requests for information but rather questions concerning opinion. It is important to highlight this because your right to review this response will not apply to the answers given to either of these questions. Further detail concerning the review process is given below.

Responses are given to each of your questions as follows:

1. What official advice has the Scottish Government published on the use of cleaner fish? In particular, how is the welfare of these fish to be safeguarded?

The Scottish Government has not published any official advice on the use of cleaner fish, particularly with respect to safeguarding welfare in relation to their use. As we hold no information relating to this part of your request, we are applying the exception at regulation 10(4)(a) of the EIRs – information not held. Further detail on the application of this exception is given below.

2. Cleaner fish have different requirements to salmon regarding living conditions. How can their particular needs be met when mixed with salmon in cages?

In order to obtain the best performance with respect to cleaner fish use then specific husbandry measures are recognised to be beneficial when using cleaner fish on salmon farms. The Code of Good Practice for Scottish Finfish Aquaculture (CoGP) recognises the requirement for farm sites to have appropriately trained staff, taking into consideration husbandry, health, and welfare, when using these animals. The cleaner fish aspects of chapters 4 & 5 of the CoGP may be of interest to you:

Code of Good Practice for Scottish Finfish Aquaculture (thecodeofgoodpractice.co.uk) 

Salmon Scotland’s website includes some further details relating to cleaner fish use:

Cleaner Fish | Salmon Scotland

The RSPCA welfare standards relating to aquaculture also cover cleaner fish:

rspca-welfare-standards-salmon-2024.pdf (rspcaassured.org.uk)

n addition, a number of publications covering the specific husbandry requirements associated with the use of cleaner fish are available online. Some examples are provided below, and additional information can be sourced through simple internet searching:

Sustainable production and use of cleaner fish for the biological control of sea lice: recent advances and current challenges - Brooker - 2018 - Veterinary Record - Wiley Online Library

Application of biological control: use of cleaner fish - ScienceDirect

Please remember that we have handled question 2 of your request out with the EIRs.

3. How many cleaner fish are used in salmon cages in Scotland?

4. What is the mortality rate of cleaner fish in salmon cages?

5. What are the causes of cleaner fish mortality in cages?

6. Annually, how many cleaner fish are culled by salmon producers in Scotland?

With respect to parts 3, 4, 5 and 6 of your request, the Scottish Government does not hold a comprehensive record of data relating to the number of cleaner fish used in salmon cages in Scotland, mortality rates and causes and the number of cleaner fish culled by salmon producers in Scotland. Therefore, regulation 10(4)(a) of the EIRs – information not held, applies to all of these parts of your request. Again, further information on the application of this exception is given below.

Additional information provided out with the EIRs

We are able to provide some further information to questions 1, 3, 4, 5 and 6, out with the EIR regulations. Under regulation 9 of the EIRs (our duty to provide advice and assistance) we would like to provide the following information on fish welfare, cleaner fish use, mortality and culling.

With respect to question 1, please note that the responsibility of welfare within farmed animals, including fish, lies with the Animal and Plant Health Agency (APHA). Further details can be found on their website:

Animal and Plant Health Agency - GOV.UK (www.gov.uk)

You may also wish to be aware that the Farmed Animal Welfare Committee opinions on the welfare of farmed fish and on the welfare of farmed fish at the time of killing have been published by Defra on the UK Government website:

FAWC advice on farmed fish welfare - GOV.UK (www.gov.uk)

In relation to questions 3, 4, 5 and 6, published information relating to the Fish Health Inspectorate’s aquatic animal health surveillance programme may include some information relating to the numbers of cleaner fish (if any present) on a particular site at the time of inspection. Observations relating to mortality and mortality cause and the culling of cleaner fish may also be present, again if relevant at the time of inspection. This does not form a comprehensive record of such activities. You can access this information through the Scottish Government website:

Publication of Fish Health Inspectorate information - gov.scot (www.gov.scot)

Some data and information relating to cleaner fish is also publicly available on the Scottish Government website. This includes:

• The farmed fish production survey data Scottish fish farm production surveys - gov.scot (www.gov.scot). This includes information on cleaner fish production and is published on an annual basis within Scotland. The main aim of the fish which are produced is for biological control of sea lice on salmon farms, however production in Scotland does not always necessarily imply the use of these animals within Scottish aquaculture.
• Scottish capture fisheries data https://www.gov.scot/publications/. Data on capture fisheries includes wild caught wrasse species, again with the main market being the salmon farming industry and the use of the animals for biological control measures. As with the production survey data, capture data does not always necessarily imply the use of these animals within Scottish aquaculture.
•  A number of previous EIR requests have covered various issues relating to wrasse and cleaner fish, some of which may be of interest to you. Responses to requests where information has been released are publicly available and can be accessed through the Scottish Government publications page Publications - gov.scot (www.gov.scot). You can search by selecting the appropriate publication type and input relevant search criteria.

In addition, the Scottish Parliament website Scottish Parliament | Scottish Parliament Website may also have information which is of interest to you. The answers to parliamentary questions, put to the Scottish Government, are publicly available along with Official Reports, which form a written record of public meetings and committees of the Parliament. You can use the search tool and input a “suitable phrase” to look for information which may be of interest you.

7. If no data is available to answer any of the above, what action does the government propose to take to ensure that such data is routinely recorded and published?

As previously indicated, data relating to the activities associated with the aquatic animal health surveillance programme in Scotland are subject to proactive publication.

The Scottish Animal Welfare Commission (SAWC) was announced as part of the Scottish Government’s Programme for Government. SAWC has a focus on protecting wild and companion animals whilst also providing scientific and ethical advice to the government. Welfare issues surrounding cleaner fish in aquaculture are currently being considered as part of the remit of the group. Further information including work plans, reports and publications are available on the Scottish Government website:

 https://www.gov.scot/groups/scottish-animal-welfare-commission/ 

As this work progresses, further recommendations and actions may emerge concerning the use of cleaner fish in aquaculture within Scotland.

Please remember that we have handled question 7 of your request out with the EIRs.

An exception applies

While our aim is to provide information whenever possible, in this instance the Scottish Government does not have the information you have requested. Therefore, we are refusing parts your request under the exception at regulation 10(4)(a) of the EIRs

Under the terms of the exception at regulation 10(4)(a) of the EIRs (information not held), the Scottish Government is not required to provide information which it does not have. The Scottish Government does not have the information you have requested because:

With respect to part 1 of your request the Scottish Government has not published any official advice on the use of cleaner fish, particularly with respect to safeguarding welfare in relation to cleaner fish use. As confirmed above, the regulatory responsibility with respect to welfare within fish falls out with Scottish Government.

With respect to parts 3, 4, 5 and 6 of your request, the Scottish Government does not hold a comprehensive record of data relating to the number of cleaner fish used in salmon cages in Scotland, mortality rates and causes, and the number of cleaner fish culled by salmon producers in Scotland. We hold some information relating to these subject areas, as referred to above, but not a total data set to be able to provide the information you have requested.

This exception is subject to the 'public interest test'. Therefore, taking account of all the circumstances of this case, we have considered if the public interest in disclosing the information outweighs the public interest in applying the exception. We have found that, on balance, the public interest lies in favour of upholding the exception. While we recognise that there may be some public interest in information about cleaner fish with respect to welfare, quantity used, mortality and the culling of stocks, clearly, we cannot provide information which we do not hold.

About FOI

The Scottish Government is committed to publishing all information released in response to Freedom of Information requests. View all FOI responses at http://www.gov.scot/foi-responses.