Lesser Nighthawks (Chordeiles acutipennis) sit on the ground of the chaparral hilltops and trill this toad-like trill on the summer nights around central Arizona. This one was at Peck's Lake [Arizona] May 20th, 1999. The sound is very hard to localize, since it is so low, quiet and "generic" (high-pitched sounds are much easier to find), and they are generally closer to you than they seem to be.
This species gets together in a kind of lek - several calling at once, and occasionally flying up in a fluttering courtship display while singing this strange song. 06
A Common Pauraque (Nyctidromus albicollis) calls in the early evening at the "El Pizote" in Puerto Viejo de Talamanca (Costa Rica), 6/22/99, 5:40 PM. I had seen this guy earlier that morning, as I walked near his ground roost in a derelict cacao plantation. He apparently never strayed far from that spot, as these recordings were made 12 hours later only a few meters from where I had spotted him.
