Getting back to grumpsgarden's original query...

One the one hand I think it's nice for all animals to be allowed and encouraged to express their natural behaviours and not at all nice for them to have to have their natural behaviours trained out of them. So that would lead me to say have a sheepdog (doesn't have to be a border-type collie, there are other sheepdog breeds) for herding sheep and don't have a gundog if you have birds you don't want retrieved.
However I do absolutely agree with Rosemary, it's hard to keep a true working collie busy unless you number your sheep in the several hundreds (or are keen on trialling so will do lots of training with small numbers of sheep.)
So on balance, in your situation personally I think I would lean towards the lab or something else very trainable and happy to be doing anything you want of it but not bred specifically for finding and putting birds up. (Sorry I know you fancy a springer but wouldn't it always be fighting its instincts with all your birds about?)
The other thing that you could look at is a collie or collie-cross that isn't very interested in sheep so is not suitable for a larger farm but could do what you need and just be a nice chap/pess to have about.
Or pretty much any trainable breed other than a pointing / flushing one.
Or maybe, if you don't want to follow the herd, you could get and train a sheeppig?
