Originally posted by Fobbo My weight issue isn't usually when I'm using/holding it but the fact that my shoulders get pretty stiff after a day of walking around carrying it.
There's the old adage, "you must suffer for your art". Luckily, over the counter pain killers can help with this!
A true back pack style bag would be a great idea when moving from one location to the next, but if you do not want to spook the critters, you may realize that a 200mm lens does not get you close enough. Either the 400mm, the 150-450 or if you have good credit and can afford the mortgage, a nice 600mm f5.6 will get you in tight!
I occasionally photograph birds out my back window (10 yards max) with a 200-500mm vintage tamron, f5.6. At 500mm it is still not close enough to get the full frame (on my K-1) filled. I add a 1.5 teleconverter to get there. This makes the lens a 300-750 f8! To keep this monster steady, I use it on a tripod with a Manfrotto gimbal mount. This may be too heavy for general walk around field work, so a monopod might be a better choice.
As for the weight you carry, keep carrying it and your body gets used to it. Mainly because you are building up the muscles you are using! You may want to hit the gym if you shoot like this regularly!
Enjoy!