Unless you are shooting continuous mode, you can select quiet mode (page 102 of the manual) to reduce some of the noise. In this mode, the mirror does not return until you release the shutter release button. When you press the shutter release button to take a picture, hold the button an extra second or two before releasing it. This will introduce a delay in the mirror up and mirror down sequence. To me, the individual noises are the same, but because they are distributed over more time, the overall noise appears to be lower.
If you are shooting in continuous mode, you might try the Camera Muzzle. It's not pretty, but the reviews look good.
Thank you very much. That Camera Muzzle is something I've never seen before. Because I'm shooting birds in continuous mode I guess there's really nothing that will help...I will read my manual and perhaps at least know about the 'quiet mode'.....Thanks a lot for your reply.