Cfxtrjtrk

There are many types of mousetraps, the traditional "snap trap" is unlikely to work well because it is dependent on pressure. Lethal traps like snap traps would be undesirable:

• Humane concerns


• Dead mice are a health concern in a closed environment


• You want the mice alive for experimentation

So that leaves you with non-lethal traps, the two that come to mind are:
Catch and Release traps:

These traps are all variations on a theme, mice come in to get the bait and the door closes behind them. There are simple mechanical ones and electronic ones, I'd assume the electric ones are better again because you don't want to be reliant on pressure sensing.

Glue traps: these are really just sheets of very sticky glue with bait in the middle. A mouse gets stuck to the glue, it's that simple. These aren't perfect as it can be difficult to get the mouse off in one piece, and you'd be introducing solvents into the atmosphere from the glue. But, they'd be useful for some hard to reach places.

Other suggestions here for trap mechanisms may have incorporated consideration of zero gravity on the operation of the trap, but not upon the mouse itself. In zero gravity, searching for a mouse is no longer an effectively 2-dimensional search of and behind surfaces. The moment a mouse escaped its enclosure and tried to walk along a surface, the very act of locomotion (by exerting force upon the surface) would propel its small mass away from the surface and into the three dimensional volume of the station.

One wouldn't need to be searching hiding places for the mouse, but simply scanning the air space. Catching it would be a simple manual process of plucking it out of the air. No matter how fast it tried running, its legs would be cycling uselessly and it would simply be drifting at relatively constant velocity until it collided with another surface, whereupon it would very quickly unintentionally launch itself back into the air.

A solution that comes to mind is to seal off one section of the ISS at a time and depressurize it.

Finding and removing dead mice may be somewhat easier than finding and removing live ones that are actively avoiding capture.

(I fully agree with the comments - removing the dead mice would be a major problem)

I believe that funnel traps should work in zero-gravity. They are not active, do not use gravity or springs. Gravity may help the mouse fall in for those with opening at the top but imho that is not strictly needed as other designs use openings on the sides.

Image source Little Green Shop

Modern problems require modern solutions!

You can't rely on gravity. what you want is a modified vacuum cleaner.
Essentially a suction device with a metal grill to catch the mouse (nobody wants to puree a rodent!) Given that the mouse is essentially guiding itself along the wall, it doesn't have anything to cling to, and gravity is a non-factor. So the suction should draw it in without issue!

You'd place food or a similar lure in an easily accessed location, use light-sensors or similar to trigger it, then power up your vacuum cleaner.
Assuming enough suction, your rodent will immediately be caught on the metal grill inside the mouth of the vacuum cleaner, unable to pull itself free of a hurricane-strength suction.

The noise should attract the astronauts, who immediately bag the rodent and put it back in the cage none-the-worse for wear.

Reset the trap and await the next mouse!

You dont want to kill the mice as they can be used for experimentation purposes, and the regular snap traps wont work because of the need of pressure for them to work, and that will kill the mouse. They would use a catch a release trap, there are electronic and mechanical traps, however electronic ones would be more effective.