1 NG - RVR

6 November 2006 4:10pm. RVR
1NG, possibly male, cutting through the RVP. The bird was in hunting mode, and was gliding slowly, then at normal speed. The bird was also flapping. I chased,with camera, on bike - yet I could not find where the bird seemed to have put down.
EOB 150 feet; OT 40 seconds.