This photo taken in July, 2008 by underwater photographer Alexander Safonov shows common dolphins and gannets (left) attacking a "bail ball" in waters near St. Johns, South Africa. Followed by thousands of hungry dolphins, sharks, sea birds and seals, the migrating sardines protect themselves from this onslaught by forming into giant balls called "bait balls" which can measure as large as 65 feet, or 20 metres, in diameter. [CFP]

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