Objectives

• 1) Can we use a rapid and inexpensive protocol to record stream water temperature and physical habitat spatially and seasonally?
• 2) Does water temperature differ spatially and seasonally throughout specific reaches of the Jack’s Fork and Current River on the Ozark National Scenic Riverways?
• 3) Does physical habitat (based on delineations developed by Rabeni and Jacobson 1993) differ spatially in different reaches of the Jack’s Fork and Current River on the Ozark National Scenic Riverways?
• 4) Does thermal and physical habitat selection of an indicator species (smallmouth bass) differ seasonally and among reaches that are thermally homogeneous versus reaches that are thermally heterogeneous?

Overview

We will refine a habitat classification for Ozark streams and make it more biologically relevant by incorporating information on water temperature.   Mapping physical habitat and water temperature is the first step in identifying possible biotic responses to climate change and other disturbances.  Therefore, we will then link the thermal mapping with habitat use of smallmouth bass, which was chosen because it is an excellent ecological indicator, has been studied extensively in Ozark streams so we have an understanding of its requirements for physical habitat, its bioenergetics, and some gross indication of how thermal conditions influence its behavior.  MDC and the National Park Service I and M Program researchers implanted transmitters into smallmouth bass in 2010 and our work will build on their initial results to track smallmouth bass for 12 months to determine seasonal movement and habitat selection, particularly temperature.  A total of 24 smallmouth bass were implanted in winter 2012 and will be tracked though 2012 to monitor movement and temperature selection.  Mesohabitat mapping of the Ozark National Scenic Riverways is ongoing and will be completed in summer 2012.  The temperature selection of smallmouth bass will be particularly interesting given the warm, dry conditions in 2012.