An extremely rare bird with half its body looking like a male and the other half like a female was captured recently at a nature reserve in southwestern Pennsylvania
One of the most enjoyable aspects of birding is that I never know what I’ll find. Oh sure, I have a good idea what to expect, but I never know what I’ll see until I get out there and look.
Such was the situation for a team of bird banders working at Powdermill Avian Research Center (PARC) located in the Laurel Highlands of southwestern Pennsylvania, 55 miles southeast of Pittsburgh. This facility, which is part of the Carnegie Museum of Natural History’s biological research station at Powdermill Nature Reserve, comprises 10 hectares of fields, hedgerows, ponds, wetlands, and streams, providing many opportunities for research with wild birds. PARC scientists conduct bio-acoustic research, evaluate avian perceptions of glass in an experimental flight tunnel to learn how to reduce bird-window collisions, and they operate a bird banding station.
It was late in the afternoon on 24 September so the bird banding team was almost finished for the day when something truly remarkable occurred: upon untangling a struggling bird from their nets, they found a songbird that looked as though it was composed of the lengthwise halves of two birds, one male and one female, that had been glued together into one individual. This bizarre bird was a rare gynandromorph, which is sometimes known more colloquially as a ‘halfsider’.
“We carry walkie talkies around the nets with us, and the field tech radioed back to excitedly say that they had a gynandromorph”, Annie Lindsay, Bird Banding Program Manager and a doctoral candidate at the University of Toledo, said in email. “[A]nd sure enough, when they brought it back, it was a half male, half female Rose-breasted Grosbeak!”