We use the cheapo wooden ones and they almost always absolutely destroy the mice, blood and guts everywhere.

I used to try to reuse them but the trigger plates often need to be re-bent which is gross to do when they covered in gibs.

That, or it doesn't kill them all the way so it's easier just to toss the whole contraption.

I did this too but was recommended to switch to copper wool/mesh.

It's a little pricier, but it doesn't degrade as much as steel and is still unpleasant for mice even after oxidizing.

We have 30's house that is balloon framing so they can pretty much move freely. I did a lot of remediation work with copper mesh and spray foam which cut back on the places we knew they were coming in.

I'll look into the fluorescent powder method, might help us see spots we missed.

That would be worse than poison for the local wildlife

The exterminator who does our baits bi-annually said they weren't anticoagulants and were fairly safe around pets.

I assume this means they aren't at risk for secondary poisoning

We live out in the woods because it's what we could afford and when you live in the woods you get a lot of mice.

For years we stuck to traps but they number of mice was overwhelming. We could burn through the big box of traps in a week. We also did all the mitigation strategies recommended by folks online and exterminators.

We finally caved and switched to bait boxes and have had almost none since.

If there was an effective way that wasn't poison, we'd take it, but afaik there isn't one yet.

That's already the case