I never had any mouse problems when I was single, but that was more than half my life ago and I had two great cats; my Mom had seven of them, but, she was crazy, anyway, the first was similar [and the only reason it comes to mind] to sherob's there, brings back memories, the other was one that picked me, was fixing a freezer and the owner's complete black cat decided I would be a good perch since I didn't seem to be going anywhere, I guess. He was the Dicky Dee franchiser, quite a nice guy, came upon the cat much as I did, asked me if I could take him.
Then came the pressures of life, wife / child / cat alergies; turns out they were both alergic to a lot more than just my cats, but... where I was going with that... and I had to get rid of both of them, [the cats] fortunately I was able to find good homes for each of them.
Oh yeah, that was when I started to have a lot of rodent problems.
I often wonder what direction my life might have gone if I'd have found good homes for... but you're not supposed to think that I guess.
I seriously dreaded opening up the ST, I knew with certainty that I had mice in the thing, fortunately, only a bit of nesting and no wiring damage or entrance through the air duct. I left the ST pretty bare bones during the layup leaving little area for them to nest, having had considerable property disruption on my other vehicles; once it was in pieces better left that way.
I didn't have the usual mice problems this season, couple things I did different were leaving the radio on in my carport -always - low volume. Fabric softener sheets in the [car] engine compartments; minimum motorcycle covering; only a short half way on the XL nothing on the ST or the VStar.
I think it's also got to do with the sweet smell of antifreeze; and it probably don't take much, just a bit of seepage around that housing followed by a nice warm place to sleep.