my outdoor cat is FIRED, effective today.

So I'm definitely second guessing my decision this fall to mulch my beds with chopped leaves and then tarping to let the wormies do their thing all winter. I peeled back a corner today to check on things, and two furry things (I'm suspecting voles) went diving under the leaves and back underground before I could hardly process what I'd just seen. I peeled back the rest of that tarp (20x50') and every bed under there is full of these rodent tunnels. A farmer friend recommends mouse traps, which I'll do, but I'd be thankful for any additional tips and tricks so I can give them the old one-two punch. I'm planning on planting this area in less than two months! Obviously my outdoor cat is FIRED, effective today.

This is out first experience with winter cover, too. We used poly weed mat. I believe it has enhanced our rodent problem also. Luckily, we have a dog who has already detected the problem.

Mouse traps in boxes, opposing holes with a trap by each hole, no bait, a lid that comes off. Eliot Coleman uses these and they work great. Maybe 8 x 8 x 4 we have about 20 of them. In the hoop concrete quick set mixed 50-50 with corn meal.......no poison so u don't hurt the owls and hawks.

It'll balance out in the spring and summer. I noticed way more voles when I used leaf mulch too. (uncovered over winter) I think you've just offered them an ideal habitat to over-winter, not increased the population, yet. Their concentration allows you to see them more easily. Come thaw, all the predators will be able to find them more easily too. Are you going to run chickens in the area? That would help speed up the massacre