摘要：Boreal lake ecosystems are changing due to natural and man-made factors. We studied the long-term stability of the habitat structure in boreal lakes and the habitat use of three duck species: the mallard (Anas platyrhynchos), common teal (Anas crecca) and common gold- eneye (Bucephala clangula). The characteristics of the lake habitat were recorded in 1989 and 2009, and duck pairs and broods were surveyed between 1989–1991 and 2007–2009 at 51 lakes in southern Finland. We found some notable lake-specific changes: lakes that had gained more luxuriant vegetation were influenced by humans, while lakes that had lost their luxuriance were small forest lakes. Beaver flooding had caused pronounced alteration to the lakes’ habitat structure. Although the habitat features of some lakes had changed, overall, landscape-level lake conditions had not changed. The habitat use of ducks varied between the two time periods in response to regional changes in duck population size and lake-specific habitat changes.
