Date: 9/30/17 7:34 pm From: David Seibel <dseibelphoto...> Subject: Re: Morton County Question
I was just writing a reply with the same reference, Chuck! Here's the relevant quote from the article, which refers to the mystery sapsucker that I found in December 2001 on the Lawrence CBC. It looked superficially like a male Red-naped but actually had too much red on the head, breast, and throat - and turned out to be a female (!) that was at least 4 years old. We wrote:
It is conceivable that the abnormal amount of red on the throat and upper > breast are the result of ... an unknown aging phenomenon, perhaps related > to reduced hormone levels (e.g., estrogen). Older females in some species > may acquire male-like plumage, e.g., Summer Tanager (Pyle 1997, Owens and > Short 1995). >
As far as I know, this phenomenon remains unknown in sapsuckers, however. The Lawrence bird was almost certainly a hybrid Yellow-bellied x Red-breasted (not Red-naped) Sapsucker, likely representing the only genes of a Red-breasted Sapsucker ever to have been transported to Kansas. The article also reviews field ID characters for sapsuckers.
Tony Leukering (https://goo.gl/P5DNuQ) discusses a similar pitfall to the one Chris mentioned, but with the species reversed: Some female Red-naped Sapsuckers have almost completely red throats, making them look like male Yellow-bellied. He also reviews helpful field marks.