If trapping just rats and mink, and no coon- try electric fence stakes.
The round fiberglass ones. I drill a hole about 1/3 up, and use electric fence wire. Push the bottom 1/3 into the mud so the wire is just into the mud. Angle them so that the top is at an angle facing away from the bank- this will keep just about all coon there if caught as incidentals.,. but not recommended for coon.
I use 100 or so of these in water trapping- light, reliable, easily seen.
If trapping rats in high competition, I've used big [U shaped stakes made with 11 gauge wire- about a foot long and pressed into bottom. You must know your sets, or mark them close by- but no one will know they are there. I don't use this a lot, but in a few locations.