Four more boxes were installed at the same site several years later, this
time with the entrance at the rear of the box and only 65mm dia. Both changes were
intended to deter other animals from competing with the gliders. When checked 8 months
later all boxes were being, or had been, used by gliders, with no sign of interference by
other animals. After a couple of years, however, rainbow lorikeets nested in one of
A smaller entrance of around 50mm or less was suggested by the work of
Barry Traill and Alan Lill, from Monash University, who found that, to exclude squirrel
gliders from a nestbox, they had to half-block a 50mm diameter entrance (thus forming a
Traill, B.J. and Lill, A. (1997) "Use of tree hollows by two sympatric gliding
possums, the squirrel glider, Petaurus norfolcensis and the sugar glider, P.
breviceps", Australian Mammalogy, 20, 79-88].
Since then, we have become aware of two 2 instances where squirrel gliders regularly
used a bat box with a 15mm slit as entrance. Although they chewed the opening to
some degree, this was very minor and the slit would still be no wider than