That series had some absolutely amazing moments in it. In the final episode there are dolphins that use sonar to drive tiny bait fish into groups so they can eat them better. The bait fish freak out, and start moving upwards, allowing the dolphins to drive them towards the surface. Knowing that the dolphins do this, a large flock of sea birds come down, and start diving hundreds of feet down to grab the bait fish that are rushing up towards them. The bait fish get stuck between the dolphins below and the sea birds above and are effectively decimated by the thousands. It's stunning photography to see a bird moving through a blue background (which leads you to assume it's flying), then seeing a fish float by above the bird. Totally surreal.