Annual Report Ant Smelt 2010: A changing role for smelt Osmerus eperlanus in the Lake IJsselmeer and Lake Markermeer foodweb? Climate- and nutrient-induced changes in ecoystem functioning

Abstract

The smelt project is part of a larger research project that aims at generating, exploring and testing different possible explanations for the observed Autonomous Negative Trends (ANT) in water fowl in Lake Markermeer and Lake IJsselmeer. The smelt populations in both lakes have been in severe decline since 1990. These declines have a large impact on the conservation of water birds relying on smelt as their prey and the fishery both on smelt and on piscivorous fish relying on smelt. In winter time the Lake IJsselmeer area is home to the largest population of waterfowl in Western Europe. The area is therefore considered to be an important Natura-2000 area. Identification of the causes of the observed negative trends will help managers (RWS) to take the appropriate restoration measures and thereby improve the these lakes as habitat for waterfowl