[pct-l] strange bird call

[Deems]

So does anyone know what this bird is? The best way I can describe the
sound is that its like a cross between an elephant and a deer snorting,
only more like an elephant. It is about 2 seconds long, and is very loud,
way louder than a deer snorting. I haven't been able to figure out what
this is by searching for "elephant noise bird" so thought I would ask the
list! I bet one of you out there knows.
~~^~~
Most likely a Nighthawk, they are really wierd. The first time I heard one, 
I thought it was one of the flying monkees from the "Wizard of Oz"! Click on 
audio if unsure.
http://en.wikipedia.org/wiki/Common_Nighthawk