Small fish feed on algae. Small fish are eaten by bigger fish and bigger fish are eaten by sea lions, who are then eaten by sharks.

小鱼吃藻类，大鱼吃小鱼，海狮吃大鱼，而海狮会被鲨鱼吃掉。

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However, researchers found that piranha most likely group together as a defense against such predators as river dolphins, caimans and bigger fish, and not to engage in feeding-frenzies.

然而，研究者们发现，食人鱼群集的时候多数情况是防御那些如淡水豚、鳄鱼和大型鱼等掠食者的攻击，而不是进行食物猎取。

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In such places red tides tend to form, some producing toxins that get into the food chain through shellfish and rise up to kill bigger fish (if there are any left), birds and even seals and manatees.

在这样的地方赤潮容易形成，有些会产生毒素，毒素通过贝壳动物进入食物链，并且增多而杀死较大的鱼(如果还有任何剩下来的话)、鸟，甚至海豹和海牛。

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Better in the sense of more and bigger fish, more consistent rises, fewer anglers and, perhaps, even more beautiful settings.

FORBES: Catskills Fly Fishing Book

Behemoths like Citigroup and American Express have bigger fish to fry.

FORBES: Magazine Article

Raymond Highsmith, executive director of the National Institute for Undersea Science and Technology, a Mississipi consortium coordinating the ship's research, says there are a lot of unknowns about the plume, but that he fears that if it is oil it could harm the small sealife that bigger fish and mammals depend on for food.

WSJ: Spill Fight Shows Progress