For you non-trappers reading this, let me give a bit of background to make what you are seeing more understandable. The metal and wire you are seeing in the photo is properly called a body-gripper trap. They are often called Conibear traps because they were invented and first marketed by a man named Frank Conibear. Now, most trap manufacturers produce their own versions. Body-gripper traps come in sizes from very small models, used mostly for mink and muskrats, to very large ones used to capture beavers.
These traps are killers and aren’t ever used if there is a chance any non-target animal is likely to encounter it. Once the trap fires, the end is near for the captured animal.
Usually, the trap strikes hard enough to render a knock-out blow and the animal becomes unconscious. The grip on it’s body or neck then prevents it from breathing and it quickly dies from asphyxiation. Picture how a common mousetrap works and you will understand the workings of a body-grip trap.
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The body-grip trap in the top photo was set in a dry ditch in a trail being used mostly by raccoons. It’s a common set. Perhaps spots like this are “weasel highways,” as well. Weasels are so small and skinny, most can pass through a trap of this size repeatedly and never hit the trigger wire.
That’s the story of this picture. The trap set and ready. The weasel hunting for its next meal captures a deer mouse and is proudly carrying it down the trail. Perhaps the weasel has gone through the body-grip trap several other times unscathed, but this time, the mouse in it’s mouth strikes the trigger, the trap fires, weasel caught and the mouse becomes a clue to this mystery novel.
The epilogue to this tale is the mouse will become bait for a coyote. The weasel will go to a taxidermist to be turned into a nature display.