by Matt Markey, Block News Alliance

ROMEOVILLE, Ill. — The now two-decades-old battle to keep invasive Asian carp out of the Great Lakes, being waged at numerous sites around the Midwest, has evolved into an uneasy standoff of sorts here on the Chicago waterway that is universally considered the front line in this biological conflict.

All indications are that bighead and silver carp, the most feared of the four Asian carp species due to the devastating impact they would be expected to have on the food web in the lakes, have not made their way past the electrical barriers here that are intended to stop their march up the Mississippi River watershed.

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