I think that you did very, very good with what you have. I have no issues with the image, it's not gory at all. Just a bad day to be a squirrel.
I've got a 70-200mm f/2.8 and often use a 1.7x teleconverter with it, I wind up with 340mm f/4.5.
Thanks all. I was afraid I would become their next meal if I got any closer. I am not sure if I missed the focus or I should have used a faster shutter speed to make it sharper. The bird was so small in my viewfinder.