Changes in the cladoceran community of Lake Superior and the role of Bythotrephes longimanus.

摘要: Abstract Introductions of Bythotrephes longimanus have resulted in reduced cladoceran species richness and biomass the Laurentian Great Lakes many inland lakes. was first observed Lake Superior 1987 but its effect on community has been unknown. We compared composition offshore Western during 2014 2015 to zooplankton surveys from 1971–2001 determine whether changes occurred. Monthly comparisons show that contribution Bosmina longirostris numbers generally twice as much 1970s than 2014–2015 while relative Daphnia mendotae increased after 1970s. These are consistent with due other To evaluate evidence for role these changes, we used data analyze patterns spatial vertical overlap between prey (Bosmina, Daphnia, Holopedium) estimates consumption by production potential prey. whose position rate made it most vulnerable suppression Bythotrephes. Of species, densities were also negatively correlated densities. findings support a hypothesis top-down effects Superior. This work informs future research furthers our understanding food web.