Wednesday, July 8, 2009
Update on PUMA egg numbers
I've had a couple of very nice responses to my RFI about Purple Martin eggs numbers and here is what I know so far.
The typical number of eggs for PUMA is 4-5. Reports of larger clutches document up to 8 eggs in a nest (Bent). Other research shows that:
"DNA parentage analyses revealed that up to 36% of the young raised by yearling parents in a Maryland colony resulted from parasitic laying (pg. 21, Morton et al. 1990)."
Morton, E.S., L. Forman, and M. Braun. 1990. Extrapair fertilizations and the evolution of colonial breeding in Purple Martins. Auk 107:275-283.
So we do know that parasitic laying takes place in Purple Martin colonies. The interesting part now is to watch this nest and see if it is successful.
Thanks to all who responded. You are the best!