Lake Sturgeon Envronmental History in the Upper Mississippi River

In many locations throughout North America, lake sturgeon populations have been nearly decimated due to overharvest and habitat degradation. As such, many agencies have initiated stocking juvenile lake sturgeon to bolster these populations. One major component to the success of propagation programs is characterizing the transition into natural environment. Thus, we sought to reconstruct movement patterns of previously stocked lake sturgeon inhabiting the Upper Mississippi River. Lake sturgeon occupying the Upper Mississippi may occupy other interconnected rivers at different life stages, however, the importance of these areas are unknown. As such, sub adult and adult were captured throughout the lower portion of the Upper Mississippi River (between Lock and Dam 19 at Keokuk, Iowa and Lock and Dam 26 at Alton, Illinois) using baited trotlines. At time of capture, lake sturgeon were measured, weighed, and fin rays were removed. We then characterized the relationship between water chemistry in these interconnected large rivers and sturgeon fin ray Sr:Ca to evaluate lake sturgeon environmental history. Overall, we documented that sub adult and adult lake sturgeon captured in the Upper Mississippi River may move throughout these interconnected large rivers at various life stages. This suggests movement patterns or environmental life history of sturgeon must be taken into account to properly manage these species. Because of this, interjurisdictional cooperation will likely be needed to ensure the success of lake sturgeon reintroduction in the Upper Mississippi River.