Lepidurus and zooplankton in Arctic lakes

Arctic ponds and tundra lakes are important but vulnerable ecosystems. Because of lack of predatory fish, aquatic life is simply structured with either planktonic Daphnia or the branchiopod Lepidurus as end users. Earlier study through the SEES expedition of 2015 showed that arctic geese play a crucial role by 1) accelerating overall aquatic production (bottom-up effect) 2) depending on goose species determining the pathway of limnetic end-users (top-down effect on Lepidurus). Because of this apparent regime shift in these ponds we will 1) test this hypothesis by further exploration and extending the basic database 2) add critical observations with respect to the foodweb chain zooplankton/Lepidurus and geese.