That could be bird or rodent damage just as easily, in which case the fence or the clips won't help much. Try them and see if they work. If not, then net the crops for birds or stand out there with a shotgun for rodents (Caddyshack style). You also could try trapping rodents - do you know whether you have squirrels or rats around? If the dmaage is occurring in the daytime, it could be squirrels. At night, probably rats. Some people like the Scarecrow sprinkler head (Google it) if you have a hose nearby -- it scares off a number of invaders.
I think it's likely enough that we have rats running around at night. I haven't seen any squirrels so far. Since the fence has been up, the dill and some of the lettuce have grown back, so I think the fence is working, but will keep watching to make sure.
The sprinkler looks really useful. Thanks for the suggestions!
I would not recommend the Scarecrow. They are cheaply made for the price and will not last very long. Check out the Orbit 62100 Yard Enforcer Motion Activated Sprinkler instead.
Hmm, good to know.