As I reread your post, you said you caught the voles in traps. I'd not come across vole traps over here... Is there a link on them?
Just found this and had to think of you
It's in German, but I don't understand much. Heavy accent.
Anyways, this guy was full-time vole catching.
I'm thinking I need greater fire power atm, as something is wrecking havok in the Small garden and I think it's larger than a vole by a good amount...
Not very familiar with the American fauna... hope it's not a grizzly :P
I wasn't exaggerating: One year they ate all pea shoots (I planted like handfuls of it as cover crops) and killed 8/10 fruit trees.
In total biomass, I might have as well fed a goat from that.
I just stick to what works: they don't eat the herbs or poatatos, so that's what I grow now.
https://www.bauhaus.ch/de/p/swissinno-supercat-wuehlmausfalle-20064536
I got something like this.
If you buy something like it, I recommend, you also buy their special tool to stamp out the hole it goes into.
It works great, I just ended up killing the wrong animal :(
edit:
It's also worth noting that some people say trapping will make them breed more. Can't really confirm, but sounds plausible...
I found it on e-bay:
I also found the tool on Amazon:
Thanks again for the info!
Yes, lower population = higher litter rates due to better food sources...