It's a little hard to see, but he appears to be at the bottom of the scale:

http://i.imgur.com/zcs7r92.jpg

side vide of the scale:
http://i.imgur.com/x3StRmv.jpg

and the top where he originally crawled in:
http://i.imgur.com/5994nkk.jpg

He's about 650 grams and 1.5-2 inches in diameter, feeding on adult mice/small rats, so I'm pretty amazed he managed to squeeze himself in there to begin with >.<