Fish

Context

Sites of Special Scientific Interest (SSSIs) can be notified if they include qualifying features under the fish criteria outlined in section 2 and 3 of Chapter 16 'Freshwater and Estuarine Fish' of the Guidelines for Selection of Biological SSSIs.  In Northern Ireland, ASSIs are selected on a very similar basis – the Guidelines for the Selection of Biological ASSIs in Northern Ireland is an addendum to the SSSI guidelines rather than an alternative. 

 
There are very few water bodies in Britain with natural fish communities, as many communities have been distorted by introductions of non-native species and/or native species from a previously restricted geographical range.  Therefore diversity does not provide a valid criterion for selecting SSSIs.  Only in exceptional circumstances e.g. extreme isolation or high research potential will SSSIs be notified on community grounds.
 
The criteria for site selection are based on the need to conserve isolated populations and rare species.  Isolated populations include examples of ecotypic or genetically distinctive fish populations worthy of conservation, such as possible post-glacial relict races of brown trout Salmo trutta in Scotland and Northern Ireland.
 
The breeding sites of certain nationally rare species, including vendace Coregonus albula, whitefish Coregonus lavaretus, allis shad Alosa alosa, twaite shad Alosa fallax and burbot Lota lota are also qualifying features, though the last is now probably extinct.  Certain breeding and spawning sites of smelt Osmerus eperlanus, a nationally uncommon species, also qualify for SSSI site notification.
 
Fish listed on Annex II of the EC Habitats Directive, and thereby qualifying as features for the selection of Special Areas of Conservation (SACs), are: Atlantic salmon Salmo salar, sea lamprey Petromyzon marinus, river lamprey Lampetra fluviatilis, brook lamprey Lampetra planeri, spined loach Cobitis taenia, bullhead Cottus gobio, allis shad Alosa alosa and twaite shad Alosa fallax.
 

Summary statistics

  SAC A/SSSI Total
Favourable condition 16% 92% 27%
Main monitoring coverage E, S S  
Reported assessments 74 12 86
Completeness of assessments 53% unknown  
Distribution of features     UK
 

Number of assessments reported by country and site type

Country SAC SSSI/ASSI
England 53 0
Scotland 12 12
Wales 9 0
Northern Ireland 0 0
United Kingdom 74 12
 

Natura features

List of Natura 2000 interest features within this reporting category

Interest feature name  
Formal name Informal name No. of assessments reported Total no. of features % assessed
Alosa alosa Allis shad 2 7 29%
Alosa fallax Twaite shad 1 6 17%
Cobitis taenia Spined loach 4 5 80%
Cottus gobio Bullhead 14 21 67%
Lampetra fluviatilis River lamprey 12 21 57%
Lampetra planeri Brook lamprey 15 20 75%
Petromyzon marinus Sea lamprey 14 23 61%
Salmo salar Atlantic salmon 12 36 33%
 
Natura 2000 comprises Special Protection Areas (under the Birds Directive) and Special Areas for Conservation (under the Habitats and Species Directive). The list presented here includes all of the qualifying interest features under these Directives, and shows the proportion of these features for which a condition assessment has been made.
 

SSSI features

List of SSSI and ASSI interest features in this reporting category

Interest feature name  
Formal name Informal name No. of assessments reported
Coregonus lavaretus Common whitefish 1
Fish assemblage Fish assemblage 1
Lampetra fluviatilis River lamprey 1
Lampetra planeri Brook lamprey 1
Osmerus eperlanus Smelt 2
Petromyzon marinus Sea lamprey 1
Salvelinus alpinus Charr 5
 
This list has not been fully standardised at a UK level yet. It is intended to show the principal constituent "feature types" for this reporting category.
 

Maps - distribution

UK distibution of reported interest features

Distribution of reported interest features.

Map showing the locations of the 10km squares in which at least one condition assessment has been reported. It does not show features that have not yet been assessed.

 

Maps - Natura

Distribution of SAC features showing assessments of favourability Condition of SAC features, with those currently reported as unfavourable-recovering shown as favourable
Current condition of SAC features
Distribution of SAC features showing assessments of favourability (where unfavourable-recovering is counted as unfavourable).
Condition of SAC features, with those currently reported as unfavourable-recovering shown as favourable
The implication of the unfavourable-recovering condition assessments is that at some point in the future these features should become favourable. This map shows the effect of that recovery by counting the favourable and unfavourable-recovering assessments together.

 

IMPORTANT NOTE: we do not have information on the timescale of the predicted recovery, which may be influenced by many past, natural and human related factors. A sustained sympathetic management regime is more likely to result in favourable condition being attained.

Key: Proportion of assessed features on 10km squares that are favourable:

Natura map legend - Key: proportion of assessed features on 10km squares that are favourable

 

Details of how these maps were produced

 

Maps - SSSI

Current condition of SSSI/ASSI features Condition of SSSI/ASSI features, with those currently reported as unfavourable-recovering shown as favourable
Current condition of SSSI/ASSI features
Distribution of SSSI/ASSI features showing assessments of favourability (where unfavourable-recovering is counted as unfavourable).
Condition of SSSI/ASSI features, with those currently reported as unfavourable-recovering shown as favourable
The implication of the unfavourable-recovering condition assessments is that at some point in the future these features should become favourable. This map shows the effect of that recovery by counting the favourable and unfavourable-recovering assessments together.

 

IMPORTANT NOTE: we do not have information on the timescale of the predicted recovery, which may be influenced by many past, natural and human related factors. A sustained sympathetic management regime is more likely to result in favourable condition being attained.

Key: Proportion of assessed features on 10km squares that are favourable:

SSSI map legend - Proportion of assessed features on 10km squares that are favourable

 

Details of how these maps were produced

 

Condition summary

Reporting category condition summary on Natura 2000 sites and SSSI

This lists the 10 different condition assessments and presents a bar chart showing the number of features within the SSSI series and the Natura 2000 series (either SPA for bird features or SAC for features other than birds). Note that for Natura 2000 we are able to estimate the number of features that have not been assessed during the 6 year reporting period - we are unable to do this for SSSI/ASSI because we do not have an overall list of notified interest features for these designations.

 

NB favourable unclassified and unfavourable unclassified have been used in this first six year cycle to get around difficulties in identifying trends in condition as common standards monitoring is implemented. It is expected that these categories will not be used for subsequent assessments of a feature.

 

Condition assessment - Natura 2000 features

The number and proportion of assessments for Natura 2000 (SAC and SPA) interest features falling into each of the condition categories
The number and proportion of assessments for Natura 2000 (SAC and SPA) interest features falling into each of the condition categories. Note that the �unfavourable� category includes all reports of unfavourable condition except �unfavourable recovering� which is shown as a separate segment.
 

Condition assessment - SSSI features

The number and proportion of assessments for SSSI/ASSI interest features falling into each of the condition categories
The number and proportion of assessments for SSSI/ASSI interest features falling into each of the condition categories. Note that the �unfavourable� category includes all reports of unfavourable condition except �unfavourable recovering� which is shown as a separate segment.
 

Adverse activities

The number of interest features where an activity has been reported as being implicated in the "unfavourable" condition of a feature
The number of interest features where an activity has been reported as being implicated in the "unfavourable" condition of a feature. More than one adverse activity may be reported for each feature.
 

Management measures

The measures summary bar chart lists the management measures relevant to the reporting category
For each "measure" the chart shows the number of interest features where that measure has been taken on a site to improve or maintain the condition of an interest feature. More than one measure may be reported for each feature assessed.
 

Interpretation

The range of fish species encountered around the UK reflects the distribution of particular habitat types.  In Scotland, for example, the list of designated features is dominated by salmonids (Arctic charr Salvelinus alpinus, Atlantic salmon Salmo salar and whitefish (powan) Coregonus lavaretus), lamprey species (brook, river and sea) and smelt (sparling Osmerus eperlanus).  English and Welsh lists contain these salmonid and lamprey species, but also include a variety of other fish species which are absent, or virtually absent, from Scotland.  These are allis shad Alosa alosa, twaite shad Alosa fallax, spined loach Cobitis taenia and bullhead Cottus gobio.  Atlantic salmon and the unique brown trout assemblage of Lough Melvin are the only fish species listed as designated features in Northern Ireland.
 
Overall, 27% of assessments reported are in favourable condition.  This is the lowest level of favourable condition reported for species features and is well below the average for species features.  It is also well below the average for all features combined.  92% of the A/SSSI and 16% of the SAC features reported are favourable.  A further 12% of the SAC features reported are unfavourable-recovering.

Shad

Three, from a total of 13, allis and twaite shad populations designated, have been reported.  One population is considered to be favourable and two in unfavourable condition.  A wide range of management issues were highlighted, but chief amongst these were agricultural operations and water quality.  Given their ecological similarities, the similarity in adverse activities between these species is not surprising.

Lampreys

Four of the six populations of brook lamprey Lampetra planeri designated have been reported: two in favourable condition and two unfavourable.  Issues requiring consideration include agricultural operations, a lack of remedial management  and poor water quality.  Three river lamprey Lampetra fluviatilis populations, out of a total number of seven, have been reported; only one population is considered to be in favourable condition.  No adverse activities were put forward to help ascertain reasons for the apparent poor performance of these populations.  Of the 24 sea lamprey Petromyzon marinus sites designated, 15 have been reported.  Five of these are considered to be in favourable condition and 10 unfavourable.  The range of adverse activities which were considered to be of relevance were relatively consistent.  Chief amongst these were water management and water quality, although a wide range of other issues, such as agricultural operations, invasive species and over-grazing were also mentioned.

Loach

Spined loach appear to be in poor condition within the UK.  All four features reported are considered to be in unfavourable condition.  Water management and water quality are a major issue for this species, although 'lack of remedial management' is also listed as an adverse activity.

Bullhead

Bullhead populations, like spined loach, appear to be under considerable threat.  13 populations are considered to be in unfavourable condition, and one (the River Camel) is partially destroyed.  A wide range of adverse activities have been identified for this species, which reflects the number and distribution of these sites throughout England and Wales.  Water management and water quality were mentioned as being a pressure in almost every site, although riparian management, agricultural operations and forestry are also important.  Other adverse activities include the presence of unspecified invasive species, lack of remedial management, and recreational disturbance.

Whitefish

Only one whitefish population has been reported; in favourable condition.  The proximity of a ruffe Gymnocephalus cernuus population to this site means that the whitefish is under potential threat.  There is also a potential threat in the form of recreational disturbance by powerboat users.

Smelt

Smelt, also known as sparling, have been reported from two Scottish sites.  Both sites are considered to be in favourable condition.  However, these results should not be treated with complacency, as smelt are predictable in their spawning behaviour, are marketable as a commercial commodity and are incredibly simple to catch.  These factors mean that it is highly vulnerable to overfishing and this activity could eliminate the population in any given year.  Furthermore, they are relatively weak swimmers, so river engineering or agricultural operations which reduce water quality could have a significant negative impact.

Arctic charr

Five Arctic charr sites have been reported.  All of the sites are located in Scotland and four out of the five were considered to be in favourable condition.  The unfavourable site is acidified and there seems to be little prospect of recovery in the short to medium term.  Pressures on these sites include water management, water quality, poor fisheries management, invasive species (such as the introduction of perch Perca fluviatilis), and recreational disturbance.  Gravel extraction was considered to be an issue for one population where the Arctic charr population spawns within inflowing streams.

Atlantic salmon

Twelve Atlantic salmon assessments have been reported.  Of these, 11 are unfavourable, and one (the River Camel) partially destroyed.  A wide range of pressures have been identified for Atlantic salmon, ranging from water management and water quality to fisheries management.  Riparian and in-stream management is also an issue and agricultural operations (including over-grazing and under-grazing), forestry and development works carried out under planning permission also feature regularly.  Aquaculture is known to be a pressure at at least one Scottish site.

Assemblages

Only one fish assemblage has been reported.  This is a whitefish (powan)/Arctic charr population.  Both of these features have been reported as being in favourable condition.  It follows that the 'fish assemblage' feature is also in favourable condition.