Killer Cali and Morals.

My cat's name is Cali but she is usually called "Killer Cali" in my family because of her love for hunting and preying upon any animal smaller than her. She is free to go outdoors or come inside whenever she wants and her bowl is always full of cat food. However, this does not stop her from killing all sorts of birds, chipmunks, squirrels, rabbits, frogs, and any other backyard creature she can find. She has been found tossing her half dead prey in the air, letting it try to escape, and then stopping it with her paw. She does not just kill animals, she eats almost every part. I have found eyeballs, torn legs, and other random animal parts in my yard. Whenever my family sees her stalking an animal, we bring her inside and tell her that what she is doing is wrong, even though we know she does not really understand this concept. We have even tried to put collars with bells on her so the animals can be warned but she has learned to walk without making a sound and also how to remove the collar outside so we can not find it. We have attempted to keep her in to the confines of my house but she always ends up going right back outside. My instinct is to stop her from hurting and killing other animals because my morals say this is wrong, but it is in her nature to want to hunt even if she is not hungry for food. Cats are carnivores, after all.

So, should humans stop animals from preying on other species? I don't think so. At first I want to say yes because I can not morally justify the killing of animals by human beings. In the case of my cat, I would be more apt to stop her because she is provided for and there is no reason for her to kill. But, in the wild, to save an animal from its predator is to disrupt the food chain. This could jeopardize an animal's ability to provide for his or herself. Now, I wonder if animals know the difference between right and wrong. With domesticated animals, especially dogs, we teach them this. But, without being taught, I wonder if an animal is able to realize he or she is doing something wrong and has the will power / ability to stop. Human beings have morals, even if they may difference between two people, but we still have them. Humans know right from wrong in almost every situation. Even though we may not always do what is right, we are still aware of the effects our choice has on something or someone. Are animals the same way? How can we know?

My question is: Do animals have a set of their own morals and how can/have human beings even observe(d) this?

Is she really a killer or is she just following her instincts?