07 April 2009
It was pointed out to me (and I did a bit of research) that our observation would constitute a (Very) early arrival date for Common Nighthawk in Mendocino County. In light of that and the fact that the observation was brief, I am modifying my report to Nighthwak Sp. much as it pains me to do so (county and yard bird). I would rather be cautious than potentially contribute erroneous data (and have a questionable bird on my lists).
Having said that, disregarding past data, if I had to wager $$ I would still bet on Common Nighthawk due to the Gestalt of the bird and the height and directness of flight.
I apologize for any confusion.