A "pin" in the lake

Its funny how my mind was thinking about two duck species Prospect Lake almost never sees despite its large size.This was yesterday afternoon as I passed by the lake.

I ran into birding photographer extraordinaire Sean Sime this after noon after leaving my job .During the frigid encounter,the news I heard was well received that Sean spotted NORTHERN PINTAIL drake yesterday along the Lake's west shore ( by a orange buoy) about 2 pm. It unfortunately didn't stick around and was long gone before I came through then. A momentary sighting yet a rare sighting with the question that circulated in my mind yesterday: why doesn't Prospect get more pintails or redheads ?

Puzzling.....