I'm enjoying the show 'Dual Survival'. They actually released a boa they caught, and explained that in a situation of absolute necessity, they would have eaten it, but since it wasn't, they preferred to let it go.
They do eat some reptiles on occasion--the last one, they ate an alligator. (But hey, we know gator tail is good eating, lol).

In a true survival situation, you wouldn't let the snake OR the turtle go. You would eat what you could and smoke the rest of the meat (if any were left).