When I first started my garden two years ago in 2010, I wasn't sure what to expect from varmits. We have some rabbits, lots of quail, occasional deer, lots of birds and squirrels. Well as it turned out, the squirrels were the only threat. I tried several things but eventually only the traps worked.
In 2010, I deployed two traps and caught 55 squirrels during the gardening season. On most days from one to four. I discovered that there doesn't seem to be anything they like better than peanut butter on bread. So I buy cheapest PB and spread a little on the bread, set the trap and sometimes I can see them waiting for me and can watch them actually doing the deed and getting caught. After traps are full, I take them on a little ride outta town and deposit in areas where there are trees.
In 2011, I caught maybe 1/2 as many. I've never had a problem in the garden. The traps are an effective buffer. Here's some photos: (in the second photo, the varmit ate the PB but not the strawberry):
Havahart 1078 Live Animal Professional Style One-Door Rabbit, Skunk, Mink, and Squirrel Cage Trap