Carpocalypse now: can the US Army Corps contain the Great Lakes carp invasion?

Position::ANDREW REEVES - Cover story

MORE THAN A HUNDRED people stepped in from the cold as a fading winter sun set behind nearby office towers. Packing into the Cleveland Public Library's basement auditorium with me this snowy Thursday in January, I knew they, too, wanted answers. Maybe Marcy Kaptur, a fiery local Democratic congressperson, had them. She strode confidently to the microphone near the front of the stage.



"We don't really need another study or another delay, we need action," she thundered, spitting her frustration. "The Corps has done this region a disservice in failing to make a final and firm recommendation about the best course of action to prevent an Asian carp invasion in our lakes." The target of her frustration was an assemblage of White House officials and primly uniformed officers of the US Army Corps of Engineers. Ostensibly, they were here to help - or, more accurately, to listen.

The town hall-style meeting was set up to collect public comment on one of the great ecological threats facing North America. It was the third of 11 such meetings the Corps held throughout the Great Lakes region in early 2014, part of the larger Great Lakes and Mississippi River Interbasin Study (GLMRIS) the Corps was conducting. This monumental engineering and public consultation project was designed to discuss ways to end Asian carp's four-decade-long northern migration.

Kaptur was the eighth speaker to address officials. As she outlined her disappointments in tones both angry and exasperated after decades of struggle, the visiting officials began shifting their weight uncomfortably in stiff library chairs. The meeting had barely begun. We had another three hours to go.

Earlier that day I packed a bag and my passport and set out for a rust belt city I'd never been to before. The five-hour drive along the Queen's and Interstate highways from Toronto zigzagged an elaborate "S" shape around two Great Lakes and across an international border to deposit me in Ohio's Forest City in time for the event. To be honest, I hadn't figured out why I was going. A frantic week of calling sympathetic editors at newspapers pitching a story about a foreign invasive fish hadn't yielded a nibble.


Asian carp had overrun the Mississippi River and threatened to break into the Great Lakes via Chicago, risking the ecological health of these massive inland seas. Yet my editors weren't biting. Knowing the details of the town hall would find a home in a book I'm writing about Asian carp, I decided to go. My wife wasn't due back at work for another two weeks and offered to tag along, drawing the line at sitting through public consultations on an US$18-billion plan to keep an alien fish out of the Great Lakes.

Asian carp, a catch-all name for four species - bighead, silver, black and grass - were introduced to American research facilities and aquaculture ponds between 1963 and 1973. Grass carp are incredible at eating weeds that choke aquaculture ponds while bighead and silver are excellent filter feeders. They eat as they breathe, using fine combs on their gills to vacuum up suspended phyto-and zooplankton in the water. They also produce huge volumes of spawn that reach maturity quickly and can survive in Just about any conditions. This makes them highly efficient pond cleaners. It also makes them a terrifying invasive.

Not long after their introduction, they escaped into the wild. Some say it happened when flood waters rose in Arkansas while others believe they were accidentally released as baitfish by unknowing recreational fishers. But their US origins matter less than what happened next. Once in the wild, silver (Hypophthalmichthys molitnx) and bighead (H. nobilis) in particular seized advantage of the opportunity to significantly expand their new-found habitat. And quickly.

Bigheads were caught in the wild by 1981. In three decades, escaped silver spread to 23 adjacent states, moving north to South Dakota and Illinois, west to Texas and east to Florida through the Mississippi and other rivers large and small, conquering new habitats and destabilizing native fisheries by outeating and outbreeding other species unfortunate enough to share a river with them. Some estimates put the total biomass in the Mississippi River - the total volume of all living plant and animal matter - at around 97 per cent Asian carp. Concentrations of silver carp are higher in the Illinois River than anywhere else in the world.

The result has been ecological destruction with mounting environmental and economic consequences on a continental scale.

Well - not quite continental. At least not yet. In early January, the Corps released its 210-page GLMRIS report outlining eight possible short-and long-term blueprints for keeping...

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