Things that go growl (and squeak) in the night

We already knew one of our cats was a mouser and when he caught a mouse in our home a year ago June, we were grateful for it. But something I haven't blogged about are all the mice he's caught since then...

Since this past spring, it's been the same routine, about once every 6-8 weeks: we wake up in the the dark - usually between 3 and 4am, but once as late as 5:55 - to the sound of growling on the little white rug beside the bed. Growling from our kitty only means one thing around here - mouse! And he'll keep sitting there, growling, until we acknowledge him. He wants us to know how awesome he is.

Light goes on, and indeed, kitty has a mouse in his mouth. If we make a move for it, he goes downstairs where we follow. Then try as we can to take it away from him, he manages to gobble it up. He's getting better at it. He used to swallow it whole, which always makes us worry he's going to choke. But lately he's learned to gnaw them in half first (natural toothbrush!). Once night, he presented us with a live mouse, so we were awoken by "grrrrrrrrrrrr.....SQUEAK SQUEAK......grrrrrrrrr.....SQUEAK." Then, after following him downstairs, we watched him finish the poor little critter off.

We're glad that, like most cats, he seems to want to show off his prize. It lets us know that we have mice. Because we wouldn't know any other way - we haven't seen or heard any sign of them.

But that's the problem, and the reason for this post. One mouse every month or two didn't seem so bad. Even though we didn't seem to have this issue until about 6 months ago, having an occasional tiny gray mouse - when we live in a suburb with a yard and trees and other outdoor critters - seemed like part of the package, along with spider crickets, spiders, moths, stink bugs, etc. But now, maybe because it's starting to get cold out, the frequency has dramatically increased. In fact, this week he caught a mouse on Wednesday and one last night. On Wednesday he was obliging enough to give D time to get a photo:

Do you think we need to call in professional help? Is this something exterminators would handle? Or do we need some kind of general contractor who would help us seal off our home? Because we don't really need help with the former. But since we aren't seeing signs of mice (until they're in this vicious beast's mouth), we have no idea where they're getting in, and they're so tiny the possibilities seem endless. 

We have to do something, don't we? Or do we just praise and reward our cat (who is probably having the best time EVER!) and let him continue to do all the work?