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Molting Feathers
This male Ruby-throated hummingbird is molting. The loss of old feathers and the growth of new is especially noticable around his beak. Molting occurs in mid-to-late summer before hummingbirds migrate south. In some cases they may begin migrating before they've finished molting. In Michigan, hummingbird bander Allen Chartier studies the progression of molt in Ruby-throats. He starts seeing molt in adult males the last week of July, and in adult females the first week of August. During this time they molt all their body feathers but not their wing or tail feathers. How the molt progresses is not clear. Chartier has examined birds with no outward characteristics of molting, but upon closer inspection has seen pin feathers all over their body under the surface.

Ann Gillis