Sorry for not getting back into the discussion sooner, I was flying.
Aircraft weather radar has absolutely no demonstrated effect on birds. There have been several reviews/studies of this, plus analysis of bird sensory systems and they just can't sense the EMP at the low power that is emitted by aircraft radar.
Similar studies on lights were "inconclusive". Caged birds had absolutely minimal reactions to strobe lights.
As for the anectdotal information of turning on the radar while taxying and the birds move, I will respectfully say that it is more related to the noise and movement of the aircraft that causes the birds to move.
However, if it makes you feel good, turn on the radar!
The most effective bird strike mitigation tools are:
1. On the airport: An effective wildlife management program supported by pilots reporting bird activity to ATC.
2. In the air: Below 10,000 feet, keep the speed to 250 knots or less - aircraft and engines are not certified for the impact of larger birds at speeds above 250 knots and the data clearly shows that if you are going to hit anything at higher altitudes it will be waterfowl and raptors.
3. Report all bird strikes - to ATC as soon as possible and to the state authority. The data is invaluable for tracking down problems.
Richard Sowden