You can probably pick some nice bear portraits, find some cool bear sounds, and make a custom party of all bears. You'd have to start them as humanoids during creation, but once you're done you can switch their models via EEKeeper to be bears (if there are bear models in IWD, I really can't remember?).
Comments
http://www.shsforums.net/files/file/1099-a-frosty-journey-the-iwdee-kitpack-beta/
Though properly implemented they can't speak common.