Most reptiles are ecto-therms, meaning their body temperature is directly related to the outside environment.  This means, they emerge on sunny, warm days to sun themselves; and retreat to dark, quiet places to hibernate on cold days.

 

Remember, not all wild animals need our help.  There is no such thing as a baby reptile.  The mother's only role is to lay eggs.  The young are on their own from the time they hatch.