Your first surmise certainly fits the bill. This
link discusses some amazing structures inherent in the albatross that enable it to glide for hundreds, if not thousands of miles.
The Condor, on the other hand has a wing designed exclusively for gliding in mountainous areas depending on updrafts for lift. It's large wing, especially in the
chord (front to aft) to length measurement doesn't fulfill the requirements nearly so well as that of the albatross, or any other large bird for that matter...