The turning point for the public was the bi-national Asian carp meeting in Peoria, Illinois, in 2006," recalled aquatic Species at Risk biologist Dr. Nick Mandrak, my guide to the highly invaded world of North American aquatic ecosystems. "It got good media coverage, and the film of silver carp jumping in the Illinois River was an internet sensation."
Especially for Canadians, who'd never seen — let alone imagined — such a thing. We were worried, and so was our government. Enough for the Department of Fisheries and Oceans (DFO) to fund Asian carp prevention as far back as 2004, when Mandrak was asked to produce risk assessments for silver, bigmouth, grass and black carp threatening to enter the Great Lakes from the Mississippi basin. Meeting with Mandrak in 2015 for the book I was then working on, The Aliens Among Us: How Invasive Species are Transforming the Planet—and Ourselves, he mentioned a colleague in charge of DFO's Asian Carp Program (ACP). I wasted little time contacting her.
As head of the ACP, Becky Cudmore oversaw what could be the best investment DFO has ever made. I visited her at the specially constructed Asian Carp Lab in the Canada Centre for Inland Waters in Burlington, Ontario. Chrome surfaces glinted under fluorescent light in a room lined with freezers and a DNA-handling area sealed by a pressure-lock door. Beside a large map depicting monitoring sites around the Great Lakes hung a 37-kilogram bighead carp from the Illinois River, a fish of squat enormity, eyes riding low on the head. Across the room schooled a further rogue's gallery: replicas of giant grass and black carp, and high-flying silver carp.
"Canada and the U.S. jointly spend $30 million annually just to keep sea lamprey at a livable level," she said, "and the Americans are spending $75 million a year to manage Asian carp. But we're still working to prevent introduction, which is far cheaper — it's only costing us $3.5 million a year to prevent introduction of these four species."
Monitoring began in 2013 with crews based out of Burlington and Sault Ste. Marie. Finding zero Asian carps would have been the best outcome, but three grass carp between 14 to 20 kg turned up on Lake Erie's north shore. Each proved to be "triploid" — a lab-induced form with three sets of chromosomes that, thankfully, cannot reproduce. Then four more grass carp were found in fall 2014 near Sandusky, Ohio, on Erie's south shore. What did this mean?
Unfortunately, several pathways remain through which Asian carps might enter the Lakes. These include the aquarium, bait and food trades — the reason it's illegal to possess or sell live Asian carps in most provinces. During 2011 and 2012, vigilant Ontario Ministry of Natural Resources patrols spent 4,000 hours inspecting import and transport companies, stopping live-fish haulers carrying over 13,000 kg of Asian carps, netting several convictions and $100,000 in fines.
But the threat continued. In late July 2015, a pair of grass carp were found at Toronto's Tommy Thompson Park, a landfill spit on the city's eastern waterfront. After an embayment being converted to a wetland was blocked off from the lake, a salvage was initiated to remove fish. The onsite biologist was immediately suspicious of two unfamiliar leviathans they found and the ACP was alerted.
Blood samples showed the two male carps to be normal diploids (two sets of chromosomes), and Mandrak was asked to assess their reproductive status. "Each had well-developed testis in breeding condition and my guess was they were looking for a place to spawn," he said. "Fortunately, there was no female around."
Also, fortunately, stable isotope analysis showed the fish to be 11 to 15 years old and hatched at U.S. fish farms, likely escapees. The ACP's response was nevertheless an excellent demonstration of prophylactic effectiveness on the part of both informed workers in the field and Cudmore's trained team. If, however, an Asian carp species was to establish in one of the Great Lakes, what was the prognosis?
"The main population front of bighead and silver carp in the U.S. hasn't moved since 2007, so frontline work is buying time on those two," she told me. "Though it takes lots of manpower, our best tool is still monitoring. Any proactivity is better than waiting — and far cheaper."
Cudmore was repeating the invasion biologist's mantra: An ounce of invasive species prevention is worth a pound of perpetual management. But the plot, as always with invasive species, thickened. Since then, several more grass carp were found in scattered locations around Lake Ontario. At least one was a diploid female capable of reproduction — a first real warning that the highly invaded waters of the Great Lakes might soon suffer their greatest indignity yet. Worse, Ohio was officially doing nothing about what was now, clearly, a breeding population of grass carp in Lake Erie.
"It's incompetence and lack of leadership. The tools and money are in place," Mandrak recently lamented. "The Canadians are furious because the Americans are dooming the Lakes by inaction."
More than anything, I would find, this was the story of invasive species everywhere.
To read Part 1, "Aliens I: Apocalypse, maybe," go to www.piquenewsmagazine.com.
Leslie Anthony is a Whistler-based author, editor, biologist and bon vivant who has never met a mountain he didn't like.