I was initially wondering if someone saw a problem with simultaneous motion detect and SDM scripts.
If you run SDM in 'Sports' mode, you set the camera to continuous-shooting and do a full press-and-release with a switch or other signal.
The screen will blank and the blue LED will light.
You then have about ten seconds for the bird to break an infra-red beam.
When it does, generate a 30msec low-to-high pulse (to both cameras) to capture the image (with flash if you want).
If the ten seconds time-out, get your arduino to 'press' the button again.
Would be great to see those images !
David