Tomatoes

This Summer I have been growing my own tomatoes. They actual plant has gotten huge. They are all about a little shorter than me and I am 5'6". These are my first plants but I would say those are some good size tomato plants. Anyhow... I found my first ripe one this week-end. I was a little excited about it even though it's a bit defective... to say the least. It has a few underdeveloped brothers growing out of its side. Boog was not deterred by them. I just hacked them off and she ate the good part. Kids.

Now I have noticed many more starting to ripen but a few have little marks in them that look like two fang teeth (wide set) that make punctures and the middle teeth on the bottom make the bite. Does that make sense? Here's a picture to help. The two smaller circles are the punctures and the bigger is the bite. Guitarman thinks it could be a cat. Does anyone know what I can do to keep small animals away from them? I would prefer to put something around them to deter but not a wiring because they are in my front yard. I will if I have to though.