Lesser Black-backed Gull is rare in Colorado in the winter months from November to April. Seeing one in September is very unusual, although single birds have popped up during the last 2 summers in Eastern Colorado. This bird is molting into definitive basic plumage from its 4th alternate plumage, so it would be a 5th cycle bird, or just over 4 years old. The photos are witness quality, due to poor light and digiscoping through a Kowa TSN-4 15x Telescope. Photos on page 2 have been autocorrected and make the gull appear darker-backed. An uncorrected photo is presented for comparison.