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Published on May 16, 2014
The seasonal movement of billions of sardines along the coast of South Africa, the greatest fish migration on the planet, is an inviting chance for cape gannets, as well as dolphins. However, collective movements on the part of the sardines makes capturing a meal a daunting task. "The Gathering Swarms" airs Wednesday, May 21 at 8 p.m. (ET) on NATURE on PBS (check local listings). For more, visit http://www.pbs.org/wnet/nature/