Yellow-rumped Warbler (Myrtle Warbler) molting into breeding plumage - (Setophaga coronata)
Yellow-rumped Warblers are abundant in Florida during the winter. Their basic / non-breeding plumage is relatively drab but we have a brief period of time in early spring when they are molting into their alternate / breeding colors. This was taken last April in my yard.
Canon Rebel XSi and Canon EF 100-400mm f/4.5-5.6L IS USM