2.1 | Study Area
The Upper Mississippi River extends from the Mississippi River
headwaters in Minnesota to its confluence with the Missouri River just
north of St. Louis, MO. This portion of the river is impounded by 29
locks and dams and highly channelized to allow for barge traffic. Our
study focuses on pools 18 to 20 from just upstream of the Iowa River
confluence to just downstream of the Des Moines River confluence (Figure
1). Along this reach, there are three main tributaries: the Iowa River
on pool 18, the Skunk River on pool 19, and the Des Moines River on pool
20 (Figure 1). These locations represent the furthest upstream extent of
most bigheaded carp reproduction in the Upper Mississippi River (Camacho
et al., 2023; La Hood et al., 2023; Larson et al., 2017), with some
evidence of reproduction up to Pool 16 (Larson et al., 2017).