Thanks for the kind words, Sean. This was hand held and also taken at the Panama City Zoo, although this guy was like me - just visiting.
I can't really give you a lot of advise for shooting birds. If I'm going to a place where I know they'll be (like a lake) and I know that I won't have to do a lot of walking, I'll usually take a tripod. After setting it up, I'll usually make sure I can swing from one side to the other and still keep the camera on a level plane. After that, I'll take a few shots and make any adjustments to the camera that I think are necessary - like adjusting the aperature setting to get a DOF that I like, checking the ISO or adding a filter (normally only a polarizer or in some extreme cases, a neutral density filter). I nearly always shoot in aperature priority and after setting everything up, I'll normally shoot a few more test shots and then check them to make sure that I'm satisfied with the results. Sometimes I'll take a folding chair with me if I'm going to be in one spot for much of the day. After getting everything set, I just wait for the opportunities.
If I had my own lake, I think I'd probably set up a permanent hide on it. This would allow the birds to adjust to it and would probably reduce the time waiting for the birds to adjust to your presence. I've never tried a portable one, although I'm sure some people have success with them. If I'm already carrying my camera, camera bag, tripod, and sometimes a small cooler and a folding chair, I just don't have enough hands to carry a portable hide. I usually try to set up under trees to hide from any birds looking down from above, but that's about all the cover I use. I also use a quick release on the tripod so I can capture birds flying in or from the lake. I seem to have better luck handholding these shots than leaving the camera on the tripod, even though the ball head swings easily. I'm sure this would not be true if the lens were not equipped with IS.
Sean, I'm looking forward to seeing some of your pics with the new lens.