Early on the morning of 18 November 2003, Avery encountered a calling Eastern Screech-Owl (Megascops asio) in an elm tree (Ulmus sp.) adjacent to the campus of Eastern New Mexico University in Portales, Roosevelt County, New Mexico. The bird was then photographed and tape-recorded on 20 November by Avery and Keller (Figure 1).
The bird was identifiable as an Eastern Screech-Owl by its sustained tremolo call and intermediate rufous plumage. In the Great Plains, 7% of all Eastern Screech-Owls are of the rufous morph (Sibley 2000). Local Western Screech-Owls (M. kennicottii) should not be rufous, as in the Western any coloration other than gray is known only in subspecies M. k. kennicottii of the coastal Pacific Northwest (Cannings and Angell 2001). The Eastern Screech-Owl at Portales gave a 3- to 4-second tremolo call on one pitch, repeating it approximately every 15 seconds. These bouts of singing often lasted for 20 minutes or more.