TFG, that sucks man! I know your neighbourhood well and it is certainly one of the most desirable ones in the city. It is very similar to where I live up north here in Silver Springs.
More than likely, you're right about it being a couple of local kids. We have had the same problem sporattically in the past 18 months. However, a fresh snowfall, 4:30am start time and keen tracking skills have seemed to end the problem.
Set 'em up, stake it out and............... send a PM.