Boat Alarm?

[Just Phishing]

I am looking for ideas related to alarms for boats. I stay at a semi public dock overnight and want the contents to remain untouched. I see blinking lights on some boats so I know they exist.

 

[Mainah]

If you cover your boat you can use a cheap car alarm with a ir proximity or ambient light sensor with a relay wired for high pull to ground as a trigger on the hood pin switch lead. You will need an adjustable sensitivity sensor either way. Without a cover an ir may still work but you may get false triggers from weather or wildlife. Whatever you do don’t use a shock sensor as will most certainly get false triggers from wave motion.