I happened upon this series being run on Animal Planet (AP) while I was working out at my gym (Turns or to be a six-part, 3 hr total, BBC series from 2004; I only saw 3 and 1/2 episodes). This represents a bit of a caveat as my expectations were probably pretty low. Nonetheless, I was impressed enough to extend my workout because I found it more interesting than most of the stuff one runs across on AP/Discovery/NeoGeo, etc.
Each episode focuses upon one natural phenomenon of massive animal populations. In all cases, these are vertebrates (2 each of fish, birds, and mammals) and their related predators. Interestingly though, the sense of numerosity that is presented rivals that for swarms of insects that often stand in as the "unstoppable force." The narration is decent if, at times, overly dramatic. And there is, of course, the tendency toward anthropomorphism (e.g., sharks and dolphins consciously working together against prey) but that is to be expected to some degree; as viewers we generally expect a narrative that jibes with humanistic behavioral themes anyway. Regardless, what makes this series more interesting is the use of CGI and animation to emphasize the animal behavior. Okay, so it owes quite a lot to "The Matrix" but it is still quite effective. I doubt I would have found the CGI so relevant if it hadn't been paired with some great, at times amazing, live action shots. I was especially impressed with the above aerial shots of bat migration, the hawk/bat and snake/bat predation shots ("The Exodus") and especially the underwater dolphin, shark, seal and gannet feeding frenzy against the sardines ("The Deep"). I should point out though that when I Googled this series, I did find production notes that indicate that some of the sequences of what one might assume are actual animals are perhaps CGI replications of flocking behavior.
Overall, the narrative managed to overcome the incessant, excessively long and common commercial breaks on AP. I would expect the series to be more effective without such breaks. It would probably be enough of an attention-grabber to keep a high school biology class quiet - no mean task.
Parents should note the PG rating is to be acknowledged. Several sequences directly feature the reality of predator/prey relationships and other animal deaths. For example, the wildebeest episode ("The Crossing") shows the tragic aftermath of a river crossing which leaves numerous animals dead or dying having been trampled by their panicked brethren.
