Here is an idea I am working on this year. Wanted to go after the weasels without using up my steel traps, so I came up with a plan to make some stacking boxes using rat traps. I use a snowmachine and sled on my line so portability is important. The wood boxes on last years' epic thread and elsewhere are works of art, but kind of bulky.
Sides and ends are 1/8" lauan plywood, bottom is 1x4.
Cup represents the bait
Lid is also 1/8". Small blocks nailed to the inside of the lid keep it centered, sorry you cant see it in the pic.
A rock or chunk of wood keeps it from blowing away (usually lol) Wire could also be used.
Used light wire to keep the sides attached to each other. Easier than blocks of wood because of all the funky angles.
Hole is 2" diameter, centered 4" from the bottom.
Got a lot of ideas from this site, thanks guys!
So far have only caught 5, but it appears that when a weasel goes in, he'll be there when you come back.
Having a lot of problems with voles, mice and shrews setting off the trap first though.
Am working on a tension adjustable trigger for the M-320 trap pictured, hopefully that will let the small guys walk and catch the ermine.
Hope this helps somebody....