garter snake in greenhouse

Question
Hello Donna,
I just discovered a garter snake, looked like a ribbon snake, in my greenhouse. I also have green anoles in my greenhouse all year long. I looked up what garter snakes eat, and it seems like the only food it could find in the greenhouse is the green anoles. My greenhouse is not heated, although I would be willing to put a heat lamp in it in the winter. (If you think I should do that, please be so kind and tell me how.) I live on the Gulf Coast, but they are predicting a cold winter. My question is: Should I leave the snake in the greenhouse or should I try to catch it and put it out? I am not sure that it would be able to get out by itself. I would love to have it in the greenhouse, but I think it might not survive there because of lack of food. What are your thoughts on that? I like the snake, but I also like the green anoles.
Thank you very much!

Answer
Hi, Stefanie,
It's entirely possible that the snake can find its way out the same way it got in, but if you are concerned, of course you may catch it and put it out.  Garter snakes are well adapted to find a place to brumate for the winter, so if it's not already below 60F, the snake will be fine in finding a place to overwinter.  It probably entered the greenhouse searching for a good spot.

It will not need require extra heat during the winter - it will find a spot that won't freeze solid, and will rest through the cold times.

Garter snakes eat worms, frogs and fish, lizards, and small mice, so it does pose a minor a bit of a threat to the anoles.  

Garters are harmless, but some individuals may of course bite when captured - the bites are almost painless, but may bleed slightly due to the snake's extremely sharp, needle-like short teeth.  If concerned about this, a pair of leather gloves should provide protection (take care that the snake's teeth do not break off if it bites a glove - broken teeth can lead to infection for them).  

If, after putting the snake out, you find it inside again, assume it knows the way in and out, lol.

If you want to look after it, a shallow pan of water can be provided, and nightcrawlers sold for fishing will probably be a welcome treat, as would small fish like feeder guppies in the water pan.