inch marshes and rspb speyside are well worth a look, you sometimes get osprey nesting on loch inch - best viewed from the church tower in kincraig.
Also feeding osprey at rothiemurcus fish farm (purpose built hide there)
HWP has quite good exhibits, tis basically a safari park of highland wildlife , and has a decent red squirel hide (wild squirels) , but in late 06 they slaughtered their wolf pack for what were essentially economic reasons and at that point (having sponsored two of the wolves since cubhood, i swore that i would never go there again or encourage anyone else to do so)
although not wildlife related ruthen barracks is worth a look if you like ruins or landscape photography.