Operating a Piezo Buzzer through an APM2.5

I am involved in a project in which we are looking to install a sonar piezo buzzer to fly around a scare birds away from a crop. Essentially I am stumped as to how to implement the sonar system with the APM2.5.

The first question is current draw. It requires 35mA and its rated voltage is 12V. Would it be best to power it separately in this case.

Next is the configuration, would it be possible to have it powered and controlled on an output pin of the APM2.5. In my mind this works as essentially tricking the APM into thinking it is a servo and using a switch on the RC transmitter to activate it.

Lastly as an extension is it possible to use a python script for example to have it trigger as it meets certain mission criteria (eg. meeting a waypoint, reaching a certain altitude).

Here is a link to the sonar device itself.

Ryan King.

[color=#004000]Moved to Hardware / APM 2.x.
Please post your your support requests into the right forum![/color]

for a so low power why not connect it directly all the time ?