Iowa's poor water quality hampers the state's multi-million-dollar fishing industry. The silt, farm chemicals, manure and treated sewage in Iowa's rivers and streams hold back fish populations by making it difficult for some game fish to reproduce.
So the state spends $2.5 million stocking more than 140 million game fish in Iowa streams every year to improve fishing.
But it may be losing even more money than that in tourism revenue. More than half a million anglers spent $336 million in Iowa in 2001 — a figure that is significantly lower than some of its neighboring states. Fishing-license sales are down in Iowa. On the other hand, the popularity of the state's clear-running northeastern trout streams show the potential for a bigger draw. So does the 10-fold increase in attendance at Lake Ahquabi near Indianola, after that lake was restored.
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When George Marzeck suggested that Iowa legislators designate a state fish, he didn't necessarily intend for his candidate — the channel catfish — to be a symbol of Iowa's polluted waters. "The channel catfish prefers clean, clear water, but it's tough enough to put up with a lot of crap," Marzeck, of West Burlington, told legislators. But without the state's stocking program, Iowa wouldn't have channel catfish, according to state fisheries chief Marion Conover. Those fish are among the species that need a rocky-bottomed waterway for reproduction. Instead, the fish face silty lake and river bottoms — a product of soil washing off farm fields and eroded land into streams.
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