Predicting the effects of climate change on native and invasive stream fishes

Session: Invasive species (2)

Meagan Kindree, University of Toronto Scarborough, [email protected]
Nicholas Jones, Trent University, OMNRF, [email protected]
Nicholas Mandrak, Biological Sciences, University of Toronto Scarborough, [email protected]

Abstract

The thermal habitat of a species is defined by its thermal preferences and tolerances.  Global climate change will alter thermal habitat availability for native and non-native invasive species leading to changes in distribution and possibly negative impacts on ecosystem function. Synergies with other stressors, such as invasive species, could amplify the effects of climate change on ecosystems and their communities. Native White Sucker and invasive Round Goby were chosen as candidate species to examine how increases in temperature may influence other interactions (e.g., distribution and feeding). The White Sucker is an important energy transfer link between the nearshore and Lake Ontario tributaries and is currently in decline. Round Goby is a recent invasive that has similar environmental requirements and, thus, the opportunity for competition and displacement is a concern. This research examines the response of these native and invasive fishes to increasing water temperature by measuring their agitation temperature and critical thermal maximum (CtMax) under seasonal conditions to predict their potential future interactions under a warming climate. Preliminary research suggests that location along the river gradient is a significant driver of CtMax, suggesting some level of phenotypical plasticity in thermal tolerance of both species.