Rattlesnakes

Question
QUESTION: I have been told that a snake "expert" can predict with certainty when rattlesnakes in a specific den area will return to hibernate in the Fall. Is it true that they will return specific months and times of day???

ANSWER: I am not enough of an expert on rattlesnakes to say for sure, but, I do believe it would be possible to predict the return of ANY hibernating animal (that returns to the same den) within a few days or weeks at the most.

---------- FOLLOW-UP ----------

QUESTION: These dens are in West Texas and I was told that the snakes will only move between 7 and 9 AM. My concern is that if weather conditions vary then that could cause a variance in the times of day they would actually be moving back to these dens. Is this true???

Answer
West Texas=desert correct?  Probably only moving at that time because they have warmed up enough to do so yet it is not so hot that they must seek shelter.  Yes, weather conditions could change but deserts don't vary a whole lot.  Can I ask why you what to know about this?