http://www.frogforum.net/tree-frogs/...ree-frogs.html

How To Sex White's Treefrogs - Reptile Forums

I could be wrong ......but I thought both males and females call?
I might be wrong again.... but I thought only a male will inflate the throat sac?
Size isn't an a good way either... until the frog is an adult.

Best way to tell is to look at the front feet for nuptial pads. Nuptial pads will appear about the same time as calls.
See links to photos - above.
The nuptial pad is a light brown patch on the inside of the thumb of a male.
A female will never have this.
I'm not sure if it is there all year round on a whites/male? ( ie like my male A moreletii) his is always there but darkens during the breeding season.

Lynn