Nutrient overloads lead to low levels of dissolved oxygen in the water, which can kill fish.

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Much is washed off by rain, ending up in local watercourses where dissolved nutrients can cause algal blooms and kill fish.

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They kill both fish and invertebrates, irrespective of their commercial value.

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Hydropower dams are unpopular with conservationists because they disrupt river ecosystems, kill spawning fish populations, and release large amounts of methane from decaying vegetation along riverbeds.

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The bottom line is that eating a Hudson or East River fish once in a while probably won't kill you.

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The pumps, however, both grind up the fish and disrupt the tidal flows, thus threatening to kill native species and inviting invasive ones.

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The U.S. Fish and Wildlife Service conservatively estimates that wind turbines already kill 440, 000 birds in the United States each year, even while providing just a tiny portion of U.S. electricity.

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"To track and spot a wolf from an aircraft, land and then kill it, is not considered to be a fair chase method, " said Alaska Department of Fish and Game commissioner Frank Rue.

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