My grandmother had an island. Nothing to boast of. You could walk around it in an hour, but still it was, it was a paradise for us. One summer, we went for a visit and discovered the place had been infested with rats! They'd come on a fishing boat and gorged themselves on coconut. So how do you get rats off an island? Hmm? My grandmother showed me. We buried an oil drum and hinged the lid. Then we wired coconut to the lid as bait and the rats would come for the coconut, and they would fall into the drum. And after a month, you have trapped all the rats, but what do you do then? Throw the drum into the ocean? Burn it? No. You just leave it and they begin to get hungry. And one by one they start eating each other, until there are only two left. The two survivors. And then what? Do you kill them? No. You take them and release them into the trees, but now they don't eat coconut anymore. Now, they only eat rat. You have changed their nature.
I had a mouse problem and asked people online for help. A former Russian sailor told a similar story. They tried this method of making a rat killer. Well instead they just bred bigger stronger rats on their ship. Ones that ate cats now.
Then they tried buying really stinky cheese in a port and baiting and ambushing rats on one of the cargo decks using bats to kill them. Got over 100 that way but the next morning a rat literally ran over the captain’s breakfast table. Clearly this didn’t work.
So finally they caught one rat and sealed it in an empty aluminum can with a microphone inserted into it at one end. They then lit a torch under the can to make the rat squeal. The mic was connected to the ship’s PA system. As the rat screamed all the other rats took heed and thousands of them jumped overboard. He said it was a scene out of a horror movie but they didn’t have rats on that ship again for years (cats managed the population after).
I don’t know how true this is but I suppose it could be and he certainly made it sound believable.
