[masraum]

length of legs tells me deer. "Pretty sure it isn't a deer - no ears, appears to have a long tail, body size is wrong."

You can't tell about any of the stuff in your sentence above because the shutter speed was way to long. A blurred item as in the photo can be nearly impossible to identify. Her game came needs a flash. Then even with the blur, you'd probably be able to tell what the animal is.

Here's your problem --> "Moving very fast." Or at least, too fast for the shutter speed.