I have a few e-mails in my inbox about wing molt in raptors that I haven't responded to yet, and I love the subject…so why not respond on the blog.
I just want to clarify one thing about wing molt. It has always been the accepted thinking that most raptors replace their primaries in order from P1 - 10 during their first molt. Is this true? Well, yes and no….P1 (the innermost primary) might be replaced first, but often birds replace P2 or P3 first…or sometimes all 3 simultaneously. When simultaneously, you see birds in spring that have large gaps in the wing and wonder how they can fly so well. So, just to clear that up, P1 is often not the first primary to drop in molting raptors. Take a look at these great examples of juvenile Red-tailed Hawks photographed by Todd Steckel molting into their first adult plumage. P1 is still juvenile…("click" on images to enlarge)
Hawk banding is a great way to learn about molt, and banding hawks in spring is different than banding in fall. In fall, birds molting are completing their molt and the last few retained feathers have not come in yet. In spring, birds are beginning a molt, and the first feathers to come in either are, or have come in. So you get to see different stages of molt between the two seasons. With the popularity of digital photography, there are thousands of images to search with the "click" of a mouse, which makes researching molt and plumages much easier!
For more of Todd's excellent photography check out: http://www.flickr.com/photos/rtsteck/