Help!!! Please! Voles, Squirrels, or is it Something Else?

Something is killing my raspberry plants... there are quarter to half dollar-sized round holes in the hardwood mulch, but they don't seem to go into the ground. One raspberry plant's leaves are dried and shriveled and another one has a couple of leaves that are dried and shriveled. Some of the blueberry and raspberry plants in the garden look like the bark has been gnawed, but no plant has been stripped (yet). I have kept the garden watered and (mostly) weeded. There is a fence sufficient to keep rabbits and skunks out, but there are squirrels and the lady at the nursery said of the holes in the mulch went into the ground, it's voles. Two of my planters with edible herbs have been totally dug up and destroyed, too. I think it's squirrels, but I don't know...

Anyone have any ideas about what is causing this and how to fix it? Does bird netting keep squirrels out, or do I have to use half inch chicken wire? Does liquid fence or any other spray work?

Thank you.

I agree, I think it is squirrels, the wholes could be there natural behaviorbehavior of burying there food, to be honesdon'they don't normally strip the bark off the plants, but there is always a first for everything, I find small holes all over the mulch wheresquirrelssquirrels and never find the nuts or berries they have hidden, I have loads of bird feeders in the garden and this in turn brings the other unwanted animals so am used to disturbing the squirrels, to be honest, of there is a lot of disturbance around the garden, it wont take you too long to see the culprits from indoors or even just a few feet away as they become very brave, cant see it being voles or moles. They make tunnels under the ground and would not make several shallow holes, you would not fine them so easy as they normally go un noticed till you actually disturb them by chance. Chicken wire would be your best chance so long as there is no entry for the animals to enter where your plants are. to deter digging you can cut a bit of the wire and lay it on the soil inside the pots of herbs, this stops the squirrels digging in the soil to bury there loot, the herbs will grow through the wire as do bulbs etc.
GWeenedck WeeNel.

I get sparrows burrowing in my mulch. Last year a grass snake was making his home in my mulch. But neither nibbled bark. They just liked the warmth of the mulch.

I've had damaging home builders in my gardens - chipmunks, mice, moles as well as rabbits and squirrels. Try a Havahart Trap and peanut butter on a cracker. Then drive MILES and MILES before releasing them.

I tried dog hair, moth balls, pepper spray and other stuff rodents don't like. Traps work the best. Well second best. I have this beautiful pair of redtailed hawks who hunt my hill. they are the absolute best.