A person who, without hesitation, attempts to impress those around him with his vast understanding and identificatin skills of birds. This person usually doesn't understand that these attemps actually make him appear even nerdier to those around him.
This person prefers to go birding rather than watch the game.
Sarah: Oh wow, that was a beautiful bird that just flew by
John: Yeah, I wonder what it was..
Mike: Well I didn't see it, but judging by your reaction it was likely a great tufted pine sparrow, male of course. It was probably foraging for honeysuckle berries, its sole food source.
Sarah: Oh....(not impressed)
John: Mike, your such a bird nerd!
Stephen: Hey Jeff, are you coming to the party later?
Jeff: Nah, I'm gunna stay in tonite
Stephen: Why? Its gunna be a great party
Jeff: I'm not gunna miss the peak of the Bohemian Waxwing migration at sunrise. I mean, its only the biggest birding day of the year, duh.
Stephen: Oh, I forgot (and don't care).....do you realize your are a huge bird nerd?