Data: Cumulative heat stress in fluctuating temperatures and implications for the distribution of freshwater fish

Predicting how rising temperatures will impact different species and
communities is imperative and increasingly urgent with ongoing global
warming. Here, we describe how thermal-death time curves obtained in the
laboratory can be combined with an envelope model to predict the mortality
of freshwater fish under field conditions and their distribution limits.
We analyze the heat tolerance and distribution of 22 fish species
distributed across North America and demonstrate that high temperatures
imposed a distribution boundary for eleven of them, employing a null
model. Importantly, predicted thermal boundaries closely match the warmest
suitable locality of the envelope model. Simulated warming suggests that
the distribution of fish species with lower heat tolerances will be
disproportionately affected by rising temperatures, and the rate of local
extinctions will be higher across fish communities in warmer localities.
Ultimately, our analyses illustrate how physiological information can be
combined with distribution models to forecast how warming temperatures are
expected to impact different species and ecological communities.