Meeting Abstract
Northern Saw-whet Owls (Aegolius acadicus) are banded across the United States, yet neither migration nor dispersal of Northern Saw-whet Owls are completely understood. In 2007 and 2008, the banding station at Whitefish Point Bird Observatory in Michigan’s Upper Peninsula began using male and female (respectively) audiolures at some owl capture sites to complement the passive mist netting that had been underway since 1994. We analyzed data from spring owl captures (1994-2015) that used either male “advertising call” audiolures, female “tssst” audiolures, or no audiolures. From the analysis of 6600 birds captured in that period, we demonstrate that 1) there was a substantial female bias in the owls caught in the passive and male audiolure nets, 2) a more extreme female bias was caught in the male audiolure nets, and 3) a nearly equal proportion of male and female owls were caught in the female-audiolure nets. The results of this analysis can be used by other researchers to provide higher capture rates of male Northern Saw-whet Owls at their stations, and should be considered when making inferences about Northern Saw-whet Owl demographics based on banding records.
