Brian, thank you for writing in. I apologize for not getting back
to you sooner. Without the ability to see them it makes this very
difficult. Usually the male will be on the nest for a longer duration.
Once the female lays the eggs she leaves the nest for the male to
fertilize the eggs. Pay attention to shadows if there are any. If
there is more than one present the largest will most likely be the
female. Once you catch them pay attention to the shape on their
anus. This will determine the sex.
Thank you again,