Reconstructing a trophic cascade following unintentional introduction of golden shiner to Lake Minnewaska, New York, USA

Abstract

Introductions of new species may rapidly and irreversibly change lake food webs and ecosystems, but such events are rarely documented as a result of inadequate pre-invasion monitoring. We examined the unintentional introduction of a fish species, golden shiner (Notemigonus crysoleucas), a small planktivorous minnow, to Lake Minnewaska, New York State, USA. We predicted that the introduction had caused a trophic cascade resulting in increased algal biomass and decreased water clarity mediated by decreasing zooplankton size and biomass. This prediction was confirmed using limited monitoring data through comparisons made between “control” lakes (both with fish in Mohonk Lake and without fish in Lake Awosting) and the “intervention” lake (Minnewaska).