If you know anything about shooting wildlife then you know that the quality of the camera you are using is not necessarily the most important factor. Sure, it is vital but not as much as the speed. Think about it for a second; wildlife is not going to wait and pose for you so you can take a picture of them. As silly as it sounds, it is worth pointing out. And, in spite of several advantages that mirrorless models have over DSLRs, many users still prefer the latter for this type of photography. That is not to say that the former style is slow, though, as it does depend on the specific model that you are talking about.