It’s full steam ahead for the busy surveys season at Forsinard Flows! One RSPB research project is designed to assess management options for helping to conserve breeding populations of common scoter – a species of diving duck once widespread in the Scottish uplands which has suffered severe declines in recent decades. The project is focussed on the scoter’s food source, macro-invertebrates, which previous research indicates may be a key factor in the species’ decline.
Throughout the summer researchers have been visiting study lochs in the Flows to investigate the invertebrate populations found there. A variety of survey techniques are being used, including stone sweeps, surface sweeps and grab sampling. Stone sweeps target invertebrate under stones by picking up a stone and sweeping a net behind to capture the invertebrate caught in the current.
For surface sweeps a net is dragged along the surface to capture anything in the upper water section, including the cast skins of mayflies which have recently emerged. A sediment grab is used in deeper water to collect invertebrates burrowing in the loch bed. By combining these, and other techniques, it’s possible to build up a comprehensive picture of invertebrate activity in and around these remote lochs – information which can then be compared against management techniques to help us to improve habitat quality, both for scoters and a range of other upland waterbirds.