I also have tried to shoot squirrels with a macro lens, which turned out to not be the easiest thing to do.
The short depth of field that you get from a macro lens makes it very difficult to focus on the right place on the moving squirrels.
You do not have time to check in the viewfinder, so it's best just to shoot and hope some pictures will be good.
What is the right place to focus on then, I think, and many other photographers that the eyes should ideally be in focus.
But it can be fun to experiment a bit, too, as with the macro lens you can try to take pictures of details on the animals if u are lucky to get close to them. :))
So here are some pictures of the experiment.
|Check out the teeth|
|This one is taken with the Wide angle lens|