This male Hooded Merganser is making a “display” by raising its “hood.” For this image, I was able to pull my car up close to the Schuylkill River near the Norristown Dam. Using my car as a blind, I waited till this bird was not too far away. Then, ( I will concede) I played the unusual call of the male. That prompted this Merganser to raise its hood and lift its head back. I assume this is a display of dominance.