Moonshine

Over the 20 years I have been banding saw whet owls there has been an ongoing discussion as to whether moon shine hinders or helps owl migration and/or captures. I believe there have actually been some studies trying to quantify the effects of the moon phase on owl captures. Unfortunately I don’t have access to those papers now. But it is a difficult question to research.

Currently we are just past a full moon with many cloudless nights. Meaning we can get around quite easily without lights. If we can then so can the owls. If the nets are visible to us then ditto for the owls. That is one effect that I have noticed several times through the years, even on poor lighting nights. Owls can obviously see the nets as they occasionally use the nets or poles to perch on.

We are still capturing owls, up to 373 for the season, but how much is this high visibility reducing our captures? Or is it hindering them at all? Questions we stew on at the station with no good answers.