On Sun, 11 Jun 2017 19:23:06 -0700, "Newgene McMensa"
wrote:

By the way, the only way I know kill them from a trap is to drown it. Not pleasant to do, but they drown in about 15 seconds. Also, if you do this, mix a spoonful of liquid detergent in the water first. That will break the surface tension and fleas will drown. If you don't, the fleas will jump out of the water.

Actually rats are expert swimmers.

National Geographic: See How Easily a Rat Can Wriggle Up Your Toilet

https://www.youtube.com/watch?v=0t2VPBF6Kp4

River rats in Al / GA traverse along the river banks.