Murine Recidivism

Trigger warning: this post discusses ways to trap mice and contains homicide scene photos.

My current house is older than the previous one I was living in, and it has a crawlspace (the other one was on a slab).  I'm not exactly sure where all of the gaps are, but mice can get into the house with little apparent difficulty.  When I was remodeling the place it was largely empty, and I was surprised to see mouse sign in the house in the fall and winter.

The picture is overexposed and out of focus, but clearly shows a mouse running around in what would become the master bedroom.  In the background, along the wall, is a spring trap baited with peanut butter that was never of any interest...that was my first (and unsuccessful) attempt at eliminating them.

Also in the background you can see long boxes: those contained blinds.  I had to replace one that the mice got into before installation; it/they snipped a bunch of the cords for use in a nest.

I then upped my game.  Maybe the peanut butter was no good the first time (I assume mice wouldn't like old rancid peanut butter any more than humans would; maybe it wasn't fresh--I got some single-serving PB containers to haul up to the house before I was living there and didn't try it on my own to see how good it was).  I got some Mini T-Rex mousetraps  (the link takes you to Shawn Woods's YouTube channel; he knows more about mousetraps than I ever will).  I got a 12-pack from Do-It-Yourself Pest Control.  The traps have mostly proven effective.  I also have set a number of Victor Tin Cat live catch mousetraps (I like the ones with see-through lids, although some have alleged the mice can chew through the plastic and escape).  I have continued to use peanut butter for bait; it does eventually go bad but seems to be palatable for some time if fresh when deployed.  Mice also like it.

I have a number of each kind of trap set out, and can go months with no mice.  Then all of a sudden, I'll get a spate of captures in one of the live catch traps.  I can catch mice in T-Rex traps in quick succession, too, but the streaks are more of a problem with the live catch traps.  Last December, I had a mouse in the same trap every morning for about five days in a row.  You can see where this is going...

I would release the mice far from the house--in some cases over 100 yards away on the other side of the road in front of my house.  Mostly I have caught deer mice.  They are supposed to have a range of about 0.5 hectares, aka 1.25 acres; a circle 262 feet in diameter is all the farther they should travel.  I thought.  You can see where this is going...

The spate of December captures ended when I released a mouse on the last day and inadvertently killed it. It started running back toward the house and I blocked it with my foot; it ran around the block and I tried to block it again, coming down on top of it by mistake.  So that was the end of that mouse and the end of the break-ins.  I began to wonder if I had a recidivism problem.

The next time I caught a mouse in a live catch trap was not long ago.  I had put one in the attic (baited with pecans) and one morning heard insistent tapping sounds, which were the mouse pushing against the box trying to get out.  I released it on the other side of the road.  A few days later I caught one in a different live catch trap and before releasing it, marked it with a magenta paint marker.  I drew a line or two on its fur and the mark wasn't very apparent, so I marked it more heavily on its left haunch, then released it and chased it into the undergrowth on the other side of the road.

Three days later I found this by the water heater.

When I took it outside, I flipped it over and saw this:

Two observations: First, it was the mouse I had caught before and marked.  You can see red streaks on its fur.  Second, I obviously caused a big problem with the heavier marking.  The mouse pulled out its fur.  My bad.  At any rate, the return of the mouse was disheartening.

It's even worse than I thought.  A mere 100 yards in no way gets it done.  I didn't read the above-linked article carefully enough.  It notes that, "Individuals that biologists have marked and then displaced have returned to their nests, on traveling 3.2 km (2 mi) in two days."  Two miles?!

This means the options are kill traps only or relocation far from my house.  I'm not averse to the latter; I can easily dump the mice out 10 miles from home.

Another option is poison, which I'm not wild about using.  I'd have to combine it with the live-catch traps, because rodents that eat poison bait and then leave the bait station to die are hazardous to predators. Compared to all of this, the kill trap is quite humane.

"Bigger than a Bread Box..."

The title used to be a common way to describe the size of something.  My parents might have had a bread box at some point when I was growing up, but I didn't really know how big one actually was.  I visualized something about the size of a loaf of bread.

When I moved into the new house, I realized I might have a need for one.  When I bake a loaf of bread, I usually leave it out for about a day to harden the crust.  I realized that with the possibility of mice--I have caught them in the house before--I needed a better plan than letting it sit on the counter unprotected.  I have never had anything go after my loaves while they have been sitting out--here or at my other house--but finding a loaf with bite marks and rodent droppings on it would not be welcome.

So I hopped online and started looking.  I was surprised that they were somewhat large-ish, certainly bigger than a single loaf.  Shown above is the box I got with one of my standard two-pound loaves.

Somewhat visible on the lid are a bunch of ventilation holes.  A tiny bug could get through them, but nothing larger.  What I have found is that the box does a good job of keeping bread fresh--maybe a little too fresh.  When I stick a loaf in there, it softens the crust a bit.  I don't store bread in it long-term; I just put it there (sometimes) on the day I bake it. Then the loaf goes into the refrigerator; that's a solution that works for me and keeps bread usable longer than just a few days.

The box is also big enough to hold a bag of potato chips, bananas that aren't fully ripe, or other items that are vulnerable to predation (not necessarily all at once).