Our 116 owl captures during our 2012 banding efforts resulted in a typical skewed sex ratio with high numbers of females. This is common across saw-whet owl banding stations and it is assumed that territorial males might not migrate or are not as attracted to the audiolure as are females, thus capturing fewer males.
Our BCCER population looked like this: 77 females (66%), 13 (11%) males, and 26 (22%)of unknown sex. So how do we determine an owl's gender anyway? A method used by all Project Owlnet banders is to measure the wing chord and the mass (weight) of the bird. Together the results of two variables can help determine the sex.
|Measuring the wing chord distance; the distance from the wrist |
to the longest primary feather using the natural curve of the wing.
|weighing the saw-whet owl in a tube to contain the bird|
|a discriminant analysis function using wing chord and |
weight to predict the gender of a saw-whet owl