Scottish Marine and Freshwater Science Volume 6 Number 4: A Mapping Study of the Overlap of Potential Eurasian Beaver (Castor fiber) Habitat and Atlantic Salmon (Salmo salar) Distribution in Scotland

Report establishing whether there would be substantial overlap of potential beaver habitat and known Atlantic salmon distribution, should beavers be formally reintroduced to Scotland.


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Table 1. Estimates of key parameters from current distributions of salmon and predicted area of suitable woodland for beavers. Potential beaver-salmon overlap is the percentage of salmon distribution within 50m of suitable beaver habitat. Major rivers (predominantly main stems) and minor rivers (mainly tributaries) refer to rivers width deemed to be above and below 10m respectively.

Awe Ayr Conon North Esk Tay Tweed in Scotland
Area of beaver woodland in catchment (m²) 18655128 16728110 21516908 23437700 121500771 86154807
Area of salmon habitat in catchment (m²) 2328842 2530925 3094610 2572830 17605365 17468072
Area of salmon habitat in major rivers (m²) 1531006 2028734 2665312 1793813 14723015 11127785
Area of salmon habitat in minor rivers (m²) 797835 502191 429298 779018 2882350 6340287
Potential beaver-salmon overlap in catchment (%) 62 71 55 73 72 47
Potential beaver-salmon overlap within major rivers (%) 70 80 61 87 75 54
Potential beaver-salmon overlap within minor rivers (%) 46 32 15 39 59 36

Figure 1. General overview of the six study catchments in which distributions of salmon rivers and suitable beaver woodland were compared.

Figure 1

Figure 2. Maps showing salmon rivers within 50m of suitable beaver woodland in six Scottish river catchments. Figure 2(a) River Ayr, Figure 2(b) River Awe, Figure 2(c) River Tweed, Figure 2(d) River Tay, Figure 2(e) River North Esk, Figure 2(f) River Conon.

River Ayr

River Awe

River Tweed

River Tay

River North Esk

River Conon


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