Kristina, the lens was a 70-200mm 2.8 with a 2x extender. Add my 20D's cropped sensor and the max range there is 640mm. Not sure if you're working on a crop sensor or not but your 300 should yield near 500mm. Just be sure to get close to the waters edge.
Great shots on your walk Ed.. I agree with your problem. Now you've got a reason to park it in front of the computer while going through your 100 images. Maybe we need a maximum number of shots one can take on such a walk to prevent the inactivity while post processing.
Of course if one would get one of those bouncy balls to sit on (Think Dwight in last season's episode of The Office) which keeps the body moving - would help.. However I think my horizon straightening and cropping may suffer with the constant movement.. 
-John


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If your wife has seen a chiro, tell her to ask him which exercises are best for her... my doc gave me specific machines to avoid, and specific ones to use to strengthen the muscles holding my 'problem areas' of my back. The stronger those muscles get, the less I have to worry about a rib slipping loose, or a vertebrae moving.
What I will do is play with about 10 tonight (about 45 minutes or so) and maybe another 5 tomorrow morning before I walk Sam. Here's a couple of selected shots taken as I walked by a doggie beach...


