Salmon mortality rates at farming sites 1997-2016: EIR release

Information request and response under the Environmental Information (Scotland) Regulations 2004.

FOI reference: FOI/17/02216
Date received: 13 October 2017
Date responded: 9 November 2017

Information requested

1. Mortality rates between 1 January 1997 and 31 December 2016 at salmon farming sites at East and West Loch Roag, Isle of Lewis, namely:

a. Eughlam
b. Taranaish
c. Vacasay
d. Kyles Vuia
e. Vuia Mor
f. Vuia Beag and
g. Gousam.

2. Information identifying the constituent cause(s) of fish mortality at the above named sites in each of the years; and

3. All reports, graphs, statistics, correspondence, and all other communications and documentation held by Marine Scotland showing or tending to show mortality rates between 1 January 2009 and 31 December 2014 at the above named salmon farms.


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 deawith 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.

You may recall my previous email correspondence explaining exactly what information Marine Scotland Science (MSS) holds in relation to mortality concerning salmon farm sites inScotland. To ensure a complete response to this request I shall reiterate relevant elements of that communication here.

MSS does not hold a comprehensive data set in relation to fish farm mortality, although we do have some site specific mortality data associated with both site inspections and a recently introduced voluntary mortality reporting scheme:

1) Please find attached details of relevant information, extracted from original records relating to inspections conducted at the above sites between 01/01/1997 and 31/12/2012.

2) Please refer to the FHI Active Publication Plan ( which details the results and findings from fish and shellfish farm inspections as a result of MSS' aquatic animal health surveillance activity, from 01/01/2013 onwards. This published resource will contain information relevant to mortality at the above listed sites, where inspections have been conducted.

3) Reposnses to previous FoI request are published on the Scottish Government website /publications/. A recent response provides summary information relating to the 'numbers, weights and causes of salmon mortalities at all fish farms in Scotland in 2016 and 2017'. Much of this information origionates from a voluntary mortality reporting scheme introduced in 2015, however all cases, relevant to the time period of your request, are also captured within the FHI Active Publication Plan.

I should also explain that in addition to the above MSS also holds weekly mortality data concerning sites within protection (formerly known as control) and surveillance zones involved with two historical outbreaks of Infectious Salmon Anaemia (ISA) virus during 1998/1999 and 2008/2009. This data relates to time periods associated with those events.

Whilst this information was not detailed in my email to you on 6 October 2017, it is not actually relevant to your request as detailed above since none of the sites specified were involved in either outbreak of ISA. I thought I would highlight this to you now given our initial general discussions on information held.

Additional information

In addition to the above, survival to harvest information is published on an industry wide basis through the finfish annual production surveys ( Shellfish/FHI/surveys). Whilst this includes mortality data it is not exclusive from that perspective and will also include losses due to fish farm escapes and predation. Theinformation is from an industry perspective and is not site or cause specific.

You may also be interested in Scotland's Aquaculture website ( which, via the Scottish Environment Protection Agency (SEPA), publishes monthly biomass and treatment reports. Within these reports information on mortalities, at a site specific level is included.

About FOI

The Scottish Government is committed to publishing all information released in response to Freedom of Information requests. View all FOI responses at

FoI-17-02216 - Information requested - table.pdf
FOI-17-02216 mortality Information.pdf


Please quote the FOI reference

Central Enquiry Unit
Phone: 0300 244 4000

The Scottish Government
St Andrew's House
Regent Road

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