Perhaps 2/3 of the Lark Sparrows I've seen in fall on the Atlantic Coast have the chestnut areas of the head replaced with a warm dark brown color. Identification Guide to North American Birds, Part I (Pyle1997), states that this is the case for many first-winter/basic I birds, but that there is much variation. He gives details of wing coverts for aging. Dave Czaplak dma3@aol.com