Having picked out a nest site, a male cormorant opens its mouth and shows off for a just-arrived female. This was a fun bit of interaction to watch recently in Lakewood, Colorado, USA. The male had a few sticks in place as it started work on a home. The female would come and the male would put on a show for it.
These cool birds are a bit odd looking but also pretty neat. Their bright orange bills and aquamarine eyes and mouths contrast with the dark plumage. These two are clearly breeding as they have tufted plumes on top of their heads. When not breeding, their heads are smooth without the tufts.