[1] Previously, most rat snakes were assigned to the genus Elaphe, but many have been since renamed following mitochondrial DNA analysis performed in 2002.

In recent years, some taxonomic controversy has occurred over the genus of North American rat snakes.

[9] Increasing night time activity allows rat snakes to catch larger prey such as birds, since female birds usually incubate their eggs in the nest at night and have decreased ability to detect rat snakes due to poor visibility conditions.

As the global climate warms, the average body size of rat snakes at higher latitudes will become larger, which will allow the species to catch more prey and thus increase their overall reproductive success.

[11] Eastern rat snake species in North America are experiencing negative shifts in their behaviour due to Global Warming and increasing temperatures.

Rat snake populations from their northern range, such as Ontario, are experiencing a shift in hibernation emergence.

[12] However, the increasing variability in temperature may cause rat snakes to emerge on a warm sunny day in the months of February or March.

[8] Therefore, the fluctuations in temperature affect the thermoregulation that rat snakes need for bodily functions like digestion and movement.

[10] The unpredictability of the weather is causing more rat snakes in their northern range to get caught in these cold snaps and freeze to death.

As rat snakes are ectothermic species, they require sunlight and heat to maintain their body temperatures.

Across their range in North America each species of rat snake has different ideal body temperatures.

[15] With ambient air temperatures over the course of their entire active season (from May to September) almost never reaching the required 28.1 °C, rat snakes in Ontario resort to basking habitats where conditions allow temperatures to rise above normal and up to 43 degrees Celsius at the hottest times of day and year.

However, with climate change and an associated increase in ambient air temperature by 3 °C, the amount of required time spent by snakes in these habitats will decrease.

They will have the potential to be generally more active during both the day and night as it will be easier for them to maintain their ideal body temperature.

[15] There will be less of a need to expose themselves in their open basking habitats, causing decreases in predator vulnerability as well as increases in thermoregulatory ability and foraging time.