I have weighed all snakes before and after hibernation.
For the ones that are interested, I have an Excell file with their weights.
To putt things short, Almost all snakes have lost 2 to 4 grams. Two snakes lost 8 and 10 grams and one snake gained 4 grams. I have no idea how that is possible...but it happened...
PM me for the xls file