For animation: no you don’t need to know modeling. The rigger will have fixed it or sent it back to the modeler. I will say that you may want to spend a little time in Blenders VSE(Video Sequence Editor). Learn to add video strips and clip them when needed. Why you ask? Motion study. Adding a video then switching to preview mode you can use the annotation tool to Mark out movements and go thru the video frame by frame. There are software designed for this if you have the money, but I just use blender’s VSE. Outside of Blender you will want to study acting too. I think Wayne talks about this in one of his courses.
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Note: this is for game animation. For video animation it depends on the area. For FX/sim and environment animation you will need physiics and/or sculpting.
Found it:
https://cgcookie.com/courses/acting-for-animators
