EUREKA — The first clear sign the fish poison was working Monday morning was a minnow-sized green sunfish turned belly-up on the surface of Eureka Lake three feet from shore.

Then another. Then five more. Then a bunch of bigger crappie, some dead, some dying. Then a large channel catfish. Then an even larger carp.

Suddenly, it looked like rainfall on the lake. Concentric rings of rippled water spread across the drawn-down lake as thousands of fish, big and small, nipped the surface in a collective death gulp for oxygen.

Then there were too many dead fish to count.

"They start to die almost immediately," said Rob Hilsabeck, a fish biologist with Region 1 of the Illinois Department of Natural Resources. "At this point, it's too late for the fish."

Too late for the fish, but the starting point for the reclamation of Eureka Lake. In 2013, thousands of game fish died after a harsh winter left the lake so depleted of oxygen that only carp could survive. The carp bred and multiplied rapidly and effectively took over the 30-acre lake. The best way to clear a lake of carp so that game fish such as bluegill, largemouth bass and channel catfish can be reintroduced and thrive is to kill them all and start from scratch, Hilsabeck said.

Monday was the "kill them all" phase of the operation.

Beginning Monday morning, Hilsabeck and fellow fish biologist Rob Miller, prepared a 55-gallon mixture of unnamed ingredients and rotenone, a root-based compound that is toxic only to fish. The two men put the compound into the water from an IDNR fisheries motor boat that zig-zagged across the lake. They returned to shore and dumped three more bright yellow 5-gallon cans of cola-colored rotenone into a plastic container then circumnavigated the lake spraying the poison toward the shore. The cans were stamped with a skull-and-crossbones logo. The solution smelled like something that could strip paint.

The two trips took less than an hour. Fish died almost immediately.

Depending on precipitation, the lake is expected to fill back up by spring. It will be restocked with game fish from state hatcheries in the spring when only catch-and-release fishing will be allowed. By 2020, the fish stock should be mature and large enough to be caught and kept.

Eureka Public Works Director Rusty Klaus said he will maintain the lower level of the lake for about two weeks before allowing it to refilll after the rotenone compound has dissipated. To mitigate the stench of thousands of pounds of decaying fish, employees will scoop and bury as many of the dead fish as it can, Klaus said.

"We'll dig a hole and bury what we can," Klaus said. "That should help some with the smell."

Rob Miller was philosophic about the stench. He uttered a homily perfectly suited for a hand-stitched sampler hung in the home of glass-half-empty realist.

"Life don't always smell like roses," he said.

Scott Hilyard can be reached at 686-3244 or by email at shilyard@pjstar.com. Follow @scotthilyad on Twitter.