By Carrie Elliott
In the Northern Great Plains mid-late June is marked by spectacular thunderstorms, an occasional mosquito swarm, and pallid sturgeon spawning season on the Yellowstone River. The week of June 16 the U.S. Geological Survey CSRP habitat crew mapped a 4 kilometer long reach of the Yellowstone River where pallid sturgeon spawning has been documented in multiple years (figures 1 and 2). Mapping was done with an acoustic Doppler current profiler and RTK GPS to generate maps of velocity, depth, and bed elevation in transects with a 15 meter spacing. These data along with side-scan sonar and sediment sampling information will allow us to monitor, model, and understand what pallid sturgeon spawning habitat is under near-natural conditions. This reach, a just a few miles downstream from the historic Fairview Bridge has had many male and female pallid sturgeon present over the past few weeks this year and contains the locations where spawning was documented in 2012 and 2013.