Compensating freshwater habitat loss—duck productivity and food resources in man-made wetlands

Abstract

The number of wetlands in Europe decreased by more than 60% by the 1990s compared with the beginning of the twentieth century. Man-made wetlands may be an effective way to compensate for the loss and degradation of freshwater ecosystems. This loss impacts the populations of declining duck species, partly due to a lack of suitable breeding opportunities. In this study, we evaluated duck productivity and invertebrate abundance in 13 man-made Finnish wetlands that were created for waterbirds. Our findings revealed that man-made wetlands have higher duck production than average natural boreal lakes. High invertebrate levels were a key factor that positively correlated with duck pair density, brood density, duckling density of the common teal (Anas crecca), and duck density during the post-breeding period. Our results suggest that man-made wetlands are a useful tool for increasing duck productivity. For upholding this status in the long term, appropriate management should involve maintaining sufficient invertebrate levels.