These are 2 different snakes and the same box. One was looking out when then other entered and the first just pulled back in as I took the second photo, so I had to combine the 2 images to make a fun half and half. Yes it is actually a bird nesting box, but hollows are important for many species and this particular box has been the winter breeding box for green tree snakes for some years now. There is quite a tangle of youngsters in there this year!