Common scoters were once widespread breeding birds across upland lakes in Britain and Ireland, with several hundred breeding pairs. Numbers have declined sharply in recent years, down to just a few tens of pairs. This project is building a detailed picture of the ecology of this species, with a view to developing conservation measures.
We found scoters strongly prefer lakes with abundant shallow water and large freshwater invertebrates, like caddisflies and mayflies - these are typical prey items of scoters at their breeding lakes. We also found scoter foraging was strongly concentrated in shallow water.
We are now testing methods of improving habitat quality for scoters. At RSPB Forsinard Reserve, we are testing whether increases in brown trout angling, at lakes which have recently had little fishing, will lead to an increase in insect abundance.