thanks for the comments.
full exif for both shots is as follows:
2005:07:21 15:12:59
80-400mm @ 400mm
600mm (in 35mm film)
1/800 sec, f/7.1
Mode: Av
Metering: Multi-segment
ISO: 200
AF
mode: AF-C
White balance: SUNNY
Flash: Off
File size: 4,486KB
Image size: 3040 x 2014
Saturation: Normal
Sharpness: NONE
Contrast: Normal
I was standing basically facing southish. This seagull was flying due east and then banked to the northeast when the shots were taken.
The sun was low in the sky and was tracking the gull until he lit up to my satisfaction and then I fired off a sequence of shots. These 2 are part of the same sequence. This bird also had reflected light of the water underneath.
hope that clears up the source of light.
Steve.