Objectives

1) Estimate and explore linkages among multiple thermal metrics that define lethal and sub-lethal effects of temperature on rare stream fish species 2) Integrate thermal tolerance results into state efforts to prioritize watershed areas that provide the greatest value for conservation of species on the periphery of their range.

Overview
Stream fish are in peril from a changing climate, particularly for species with restricted distributions or populations on the southern edge of their range. To deal with temperatures beyond their physical capacity, fishes must move, adapt, or die. However, little is known about temperature optima, critical temperature limits, or adaptive capacity to tolerate increasing temperatures for many of these species. We propose to measure temperature optima and tolerance of two stream fish that are vulnerable to climate change. The Ozark Shiner is only found in Missouri and Arkansas and is being considered for listing under the Endangered Species Act, and the Blacknose Shiner may be declining on the edge if its range in Missouri, Iowa, and Illinois. We will use temperature optima and tolerances determined from lab experiments together with existing data and models of current and future stream temperatures, barriers to fish movement like culverts and dams, and proximity to existing conservation areas to aid conservation planning. This information will help identify where these species are most likely to occur in the future when water temperatures warm, identify barriers to accessing those areas (like dams and stream crossings) that can be prioritized for restoration, and identify nearby state or federal conservation areas that already offer some protection.