Jim, I'd say this close the normal end of the bulk of nighthawk migration- from mid August to mid September. My latest record for Montgomery County is October 8 at Hughes Hollow. As part of a cooperative study of nighthawk migration I have watched for at least two hours before sunset from August 18 to September 18 this year. My last big flight was on September 7 right after "Dennis" left, my last significant flight was on September 11, and like you my last sighting was on September 17. Paul Woodward >I saw a single Common Nighthawk flying over Gaithersburg on Friday, >Sept. 17. This seems quite late to me, though my notes show me >that in 1996, I was seeing them in early October. > Jim > > Jim Felley > Smithsonian Institution > irmss668@sivm.si.edu > >