A second-year (SY) Northern Saw-whet Owl that survives to its second 1 Jan. “birth date” changes from an SY age class to the TY (third-year) Bird Banding Lab age class. As was the case for the HY to SY age class change, there is no plumage change involved. From 1 Jan. through the beginning of an owl’s third prebasic molt, the plumage described as characteristic of an autumn SY owl becomes the plumage that is characteristic of an TY saw-whet owl. These owls are in their third year of life, and until they start their third prebasic molt the pattern of fresher outer primaries and inner secondaries is characteristic. TY can only safely be used as an age class until sometime in June when the prebasic molt begins. For a discussion of this plumage, and illustrations of it, please see the Second Year sub page.
