The dismissive reaction you are getting is almost amusing. Personally, I loved your thought experiment and would like to offer a few more for the Lurkers:
Consider the will to live: Imagine a dog whose muzzle is held to completely shut off the air. Or pull a fish out of the water and toss him onto the dry ground.
Consider the willfulness of choice: Imagine a live dog with a choice between a plate of lettuce or a plate of cooked steak. Or perhaps a mouse with a choice of a bottle cap or a tablespoon of peanut butter.
Consider willfulness in anticipation: Imagine tossing a stick for a retriever time and again and then moving the hand without releasing the stick. Or approach a bear cub with a mother bear standing nearby.
Not considering any of the above is also an act of free will.
I don't see much choice in your examples. How about a cat climbing down from a tree. Have you ever watched? It's really interesting, particularly if there are lots of branches. A cat's preferred method of descending is head first, something that scares the willies out of me. My cats will climb down ladders head first, but you can tell they don't like it much. Their behavior looks exactly like that of a person doing something mildly frightening, like crossing a pond on stepping stones. Or climbing down from a great height.
Free will, or the impression of it, is most evident in situations where there are real choices. The more coersive the situation, the more predictible the response. If you want to observe something that looks like free will in animals, you have to put them in a situation where the outcome isn't predictable.