All fish, minus opah and some tunas, are cold blooded. Thus, their body temperatures are regulated by the environment around them. Every fish species has an optimal temperature range — not only for survival, but also for growth and reproduction. Fish exhibit control over their thermal environment by seeking waters that are closer to their temperature optimum when waters become too warm or too cool.
High and low temperatures that are lethal for a particular species determines the distribution and abundance of its population. With water temperatures trending upward — the result of climate change — many fish are responding by shifting their latitudinal range, expanding their range, and/or moving to