Can Asian Carp Reproduce in the Upper Missouri River Basin?

There are many questions about the potential impacts of invasive species on invaded ecosystems. The Upper Missouri River Basin is at the front of the bighead and silver carp invasion, and spawning success in prairie streams has not yet been documented. Our research targets pelagic larvae, including bighead and silver carp, to document whether these invasive species are reproducing in three tributaries to the Missouri River in eastern South Dakota. We deployed 500µm drift nets biweekly from April to September 2010 and 2011 to collect larvae, which were picked and identified to lowest possible taxa. Dominant species in 2010 were Notropis stramineus, Cyprinus carpio, and Lepomis spp., which shifted to Ictiobus spp., C. carpio, and Aplodinotus grunniens in 2011. Although we did not collect any bighead or silver carp larvae, we collected other drifting larvae, indicating that it should be possible to detect bighead and silver carp larvae if they are reproducing in sufficient numbers. If bighead and silver carp do reproduce in these systems, they may decrease available resources for native pelagic larvae, which may utilize similar resources during a similar timeframe. Understanding larval production by bighead and silver carp will improve predictions of the ecosystem effects and ultimately strengthen management strategies to ensure the sustainability of invaded prairie streams.