The Zoobenthos of Loch Leven, Kinross, and estimates of its production in the sandy littoral area during 1970 and 1971

The available information, both published and unpublished, on the zoobenthos of Loch Leven has been studied and tabulated. There have been a number of major changes in the community over the last 100 years-notably a reduction in diversity of the fauna with the disappearance of many species of invertebrates, particularly Ephemeroptera, Odonata and Coleoptera.The existing macro-invertebrate fauna is dominated by larval Chironomidae, but Nematoda, Mollusca, Annelida and Crustacea are also of importance. Dramatic changes have taken place in the chironomid population during the present study (1968-71), notable among which has been the disappearance of Endochironomus. Production studies of the two dominant larval Chironomidae (Glyptotendipes and Stictochironomus) in the sandy littoral area (42 per cent of the loch bed) gave annual estimates of 40·5 and 1·2 g (dry weight)m2 respectively for 1970 and 5·0 and 10'2 g/m2 for 1971. Speculative estimates of the entire zoobenthos production in 1970 gave a value of 46.5 g/m2. The significance of these results is briefly discussed.