Rogers, Sean M.Tufts, Teresa2018-07-232018-07-232018-07-13http://hdl.handle.net/1880/107473Temperature is the most important environmental factor influencing fish abundance and distribution but, as temperatures rise globally, the consequences for fishes remains largely unknown. I used populations of ninespine stickleback (Pungitius pungitius) from the northern and southern parts of their range in a common environment to characterize thermal traits in association with varying temperatures. Cold tolerance differed between populations but heat tolerance did not. Furthermore, juveniles demonstrated less tolerance for temperature extremes. When incubated at elevated temperatures, populations exhibited higher plasticity in cold tolerance compared to heat tolerance. Plasticity in heat tolerance was associated with a number of trade-offs. The data suggest that cold tolerance is locally adapted and phenotypically plastic while heat tolerance is conserved and phenotypically restricted in this species. My thesis highlights the need for the inclusion of various life stages, time scales, and biotic interactions in climate change research to better predict its impacts on fishes.engUniversity of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission.thermal tolerancetemperatureFishclimate changeBiologyAssessing Temperature Tolerance in Ninespine Stickleback (Pungitius pungitius) in Response to Climate Changemaster thesis10.11575/PRISM/32655