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ANNEX C: INTERIM CRITERIA FOR ASSESSING FISH IN RIVERS
Table C1: Interim criteria for assessing fish in rivers
Status | River type |
|---|
| Salmonid rivers in which migratory salmonids 1 and brown trout as well as other fish species are expected to be present. | Salmonid rivers in which brown trout are not expected but migratory salmonids 1 as well as other fish species are expected to be present. | Salmonid rivers in which migratory salmonids 1 are not expected but in which brown trout as well as other fish species are expected to be present. |
Classify as 'good or high' | (a) all expected age classes of migratory salmonids and brown trout present; and (b) number of individual fish of all species per metre 2 = 0.1 (2) . | (a) all expected age classes of migratory salmonids present; and (b) number of individual fish of all species per metre 2 = 0.1 (2) . | (a) all expected age classes of brown trout present; and (b) number of individual fish of all species per metre 2 = 0.1 (2) . |
Classify as 'moderate' | (a) migratory salmonids absent but other expected migratory species and brown trout present; (b) migratory salmonids present but with one or more age classes missing; (c) brown trout absent but other expected resident and migratory species present; (d) brown trout present but with one or more age classes missing; or (e) number of individual fish of all species per metre 2 < 0.1 and > 0.01 (2). | (a) migratory salmonids present but with one or more age classes missing; or (b) migratory salmonids present but number of individual fish of all species per metre 2 < 0.1 and > 0.01 (2). | (a) brown trout present but with one or more age classes missing; or (b) brown trout present but number of individual fish of all species per metre 2 < 0.1 and > 0.01 (2). |
Classify as 'poor' | (a) all migratory species absent but other fish species present; (b) trout and migratory salmonids absent but other species present; or (c) number of individual fish of all species per metre 2 _ 0.01 (3) and > 0. | (a) migratory salmonids absent and number of individual fish of other species per metre 2 < 0.1 and > 0 (2); (b) all migratory species but resident fish species present; or (c) number of individual fish per metre 2 _ 0.01 (3) and > 0. | (a) brown trout absent and number of individual fish of other species per metre 2 < 0.1 and > 0 (2); or (b) number of individual fish per metre 2 _ 0.01 (4) and > 0. |
Classify as 'bad' | No fish species present | No fish species present | No fish species present |
Notes on Table C1
(1)"Migratory salmonids" means Atlantic salmon and sea trout
(2)Where SEPA has evidence that the river is likely to have supported > 1 individual fish per metre 2 under high status conditions, it may classify the water body as being 'moderate' if the number of individual fish per metre 2 is < 0.75 and > 0.5.
(3)Where SEPA has evidence that the river is likely to have supported > 1 individual fish per metre 2 under high status conditions, it may classify the water body as being 'poor' if the number of individual fish per metre 2 is _ 0.5 and > 0.
Table C2: Standards for the hydromorphological quality element, 'river continuity' to be used in assessing impacts on the movement of fish species in river systems
Column 1 | Column 2 | Column 3 |
|---|
High | Good | Moderate |
|---|
Severe loss of fish access to rivers draining less than 1 % of catchment area of the water body | Severe loss of fish access to rivers draining less than 5 % of catchment area of the water body | Severe loss of fish access to rivers draining less than 20 % of the catchment area of the water body |
Notes on Table C2
(a) The condition limits refer to lost access by fish to the catchment areas during that part of the year in which fish movement to those areas would normally be expected to occur in the absence of man-made barriers to fish movements.
(b) Catchment areas known to be naturally inaccessible to the fish species should be disregarded when applying the condition limits.
(c) Where a loss of access to waters draining smaller catchment areas than those referred to in Column 1, 2 or 3 is assessed as having, respectively, more than a very minor, slight or moderate adverse impact on fish, the criteria in Column 1, 2 or 3, as the case may be, shall not apply and the water body will be classed according to the estimated impact on fish populations. This may be the case where the waters are particularly important in the lifecycle of the fish species concerned.
(d) A severe loss of access means that more than 80 % of fish that would otherwise access the catchment areas concerned are judged unable to do so because of man-made barriers to their movements.
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