The Spawning of Perch (Perca fluviatilis L.) in Loch Leven, Kinross, Scotland

Investigations were carried out in 1979 and 1980 into the location of spawning grounds of perch in Loch Leven, the comparative intensity of their use and the duration of the spawning period. Spawning was found to take place in depths of 1–5 m and there was an indication that depths around 3 m are preferred. Silt and mud apparently inhibit spawning on exposed shores down to 2.5 m although natural shelter probably ameliorates this. Macrophytic vegetation is rarely present at the preferred depths, therefore, artefacts and artificial substrates must be most frequently used. Spawning started about 25 April in a ‘mild’ spring and about 9 May in a ‘cold’ spring. The duration of the spawning period was 4–5 weeks. A double peak in spawning intensity was found in 1979 and, if valid, could indicate a division of spawning fish into two groups, possibly by age as the peaks were not associated with the location of spawning sites. Although spawning tended to be more intense on the southern shore and around one of the islands almost any part of the loch down to 5 m may be used.