I'm actually not sure if I'm asking this properly, so I'll try to be as clear as possible.

In HG/SS, when you go to the various places to capture the Birds, is it possible to soft reset your game before hand to get a different nature bird beforehand? Or is this determined once you initially start the game?

The nature is set when you encounter them but You can save right next to the legendary and then keep Soft resetting an till you get the right nature that you want.

Exactly what I was hoping for. Thanks a bunch.

Your welcome anytime.

If you have the necessary hardware, you can actually pinpoint the very moment you want the exact nature and IVs you want on any Pokemon. Game Freak has programmed setting stats to coincide with the clock on your DS.

But understanding and taking advantage of that algorithm takes the same time as soft resetting.