When large swarms of tuna fish gather together, you get a bait ball. It’s actually a last-ditch defensive measure adopted by small schooling fish when they are threatened by predators. However, bait balls are also conspicuous, and when schooling fish form a bait ball they can draw the attention of many other predators. As a response to the defensive capabilities of schooling fish, some predators have developed sophisticated countermeasures. This particular example was photographed by Octavio Aburto in Mexico. Continue reading for more.
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