That is the funniest story I have ever heard. Props to you.
As for a solution..Have you tried changing the place of the bike where you ark it? If changing the place does not solve the problem then I suggest you think about investing in an air gun. I am not suggesting the slingshot because it is easier to aim with a gun.
*Warning..Do good practice before you use the air gun, else you might lose another side mirror 
Another importance question... Are you sure its one and the same crow teasing you? What if the whole crow community has fallen in love with your bike. If that is the case no one here can help you. Time for some 

