If you know me, you’ll know I’m always looking for a better way. “Better” means whatever it means, but I have to ask:
Your own pond seems well-kept, so I’m assuming you could walk around it without much danger, even in the dark, yes? I’m assuming you used a flashlight last week?
Why not just put on some dark clothes, pack a pistol just in case, and wander up on them in the darkness? Take your time, be slow, careful and quiet. If they’re just looking to get closer to nature (as in “au naturel”), or if they are up to no good, a Sudden Appearance of a Very Bright light from Very Close is a lot more effective (in terms of terrorizing trespassers), than anything you could beam them with from the porch. Especially if you pop a couple of rounds into the ground at your feet (safely, of course!!) as you pop on the light (assuming they’re actually ne’er-do-wells and not just necking).
For the maximum deterrent effect, you’d want to exercise some self-control to keep from LOL-ing at them while they were still in ear-shot… In fact, a complete lack of vocal sounds from you would probably have the most lasting psychological impact.
But, like wild animals, if they see you coming, you’ll never get close enough.
OTOH, my first thought would be to prepare by practicing in daylight with a shotgun (birdshot only) so you can lob loads of birdshot high enough to not be dangerous, but get the load to splash around the far side of the pond. If you’ve ever been bird hunting in a popular spot you know what that “shot shower” feels like. This plus the LASER pointer, plus any flashlight if you must, would make a pretty convincing “GET OUT” message in the darkness.
However, comma, my Best Advice (“Greater Good” and all that) would be to adopt a dog & teach it to run madly around the pond barking its fool head off the whole way. There are very few people who’ll stick around to see if it’s “bad” or just noisy. And in the meantime you’ll be a hero by giving a dog a home and a job to do.
