Foreword Reviews


Overrun cover and author

As the world’s faithful struggle for proof of the existence of God, the rest of us weep at all the evidence showing that humans have long been playing God (or, Antichrist) with the green Earth—from hunting woolly mammoths and countless other species to extinction to raising global temps by spewing billions of tons of carbon dioxide into the atmosphere.

This week’s interview discusses the infiltration of nonnative Asian carp into US waterways. The fish were originally introduced to help control troublesome aquatic weeds but quickly found their way into other bodies of water—changing freshwater ecosystems from Florida to Arkansas to Illinois. The great worry amongst many Midwestern environmentalists is that the carp will somehow breech the preventative measures set up to keep the fish out of the Great Lakes and soon decimate the existing populations of salmon, lake trout, walleye, whitefish, cisco, and other gamefish. Larger and more adaptable, the carp is a real threat to the Great Lakes’s multibillion dollar sportfishing industry.

Overrun cover
In the January/February issue of Foreword, Barry Silverstein gave a starred review to Overrun: Dispatches from the Asian Carp Crisis, a new project by Andrew Reeves and ECW Press. With our offices only a few hundred feet from Lake Michigan, we were compelled to seek out an update on the issue and quickly set up this interview between Barry and Andrew. Yes, there’s lots of battles to be fought—environmental, social, political, etc.—but conversations like these remind us to stay engaged, to communicate with our elected officials, so as to influence the times as best we can.

When Asian carp were first introduced to American waters in 1963, they were widely seen as a natural, environmentally sound way to manage nuisance aquatic weeds. Now, however, they are viewed as a species that is invading our waterways. When and how did this change occur?

The change happened at different times and in different ways for grass, bighead, and silver carp. And in many ways, for grass carp, the situation is complicated by the fact that sterile fish certified by the U.S. Fish and Wildlife Service are still commonly bred and sold across state lines to dozens of state resource agencies, farmers, and golf course operators to help keep their irrigation canals and ponds free of clogging invasive weeds.

So for grass carp, the tide of public opinion turned against them in the mid-1970s as news of their escape from government facilities and private hatcheries in the South and Midwest into open waterways came to light. But through the work of pioneering fish farmers like Jim Malone in Arkansas and others in state and federal government agencies, grass carp—sterile, grass carp, at least—found a new lease on life and an accepted (though still controversial) role to play in American ecosystems.

Bighead and silver carp (known together as “bigheaded carp”) are another story. Based on research coming out of China in the mid-1960s, Malone and other fisheries experts interested in how exotics could be harnessed for biological control purposes turned their attention to bighead and silver carp for their ability to be cultured alongside grass carp, all while cleaning catfish ponds of excess plant life that often caused algal blooms.

But within a decade of their intentional importation, fish farmers had soured on the idea of using bigheaded carp to control algae in catfish ponds, largely because the carp grew so big and thrashed so violently that they threatened the health and safety of fish farmers trying to process their catfish. Not only that, but the carp would often crush catfish as tanks were emptied.

Another purpose for bighead and silver carp was found in cleaning sewage lagoons. After changes to the Clean Water Act came into effect in 1972, small governments needed to find more environmentally friendly ways of treating their human sewage. It was believed that bigheaded carp (silver, in particular) would be able to suck up those excess nutrients in a far more cost-effective way than installing expensive machinery to treat waste.

But as experiments were underway in Benton, Arkansas, with money from the Environmental Protection Agency to see if this plan would work, a profound shift in the political climate with the election of Ronald Reagan to the White House changed things dramatically. The EPA budget was radically slashed, and the funds needed to see whether carp were able to treat sewage lagoons effectively dried up.

And yet. Early results showed the carp were up to the job, yet the economics largely made sense only if people wanted to buy the fish for human consumption. But when few showed any desire to eat fish reared on human excrement, the experiment was dead in the water.

After that, there was never another use for silver and bighead carp.

You indicate that managing the Asian carp crisis “has become the largest cooperative ecological endeavor undertaken” in North America. Who are some of organizations that have led the fight, and what does this effort suggest about potential collaboration on other major environmental issues?

As I dug into this, I really was amazed at just how many agencies have been dragged into the Asian carp fight, and even found a few that were created just for the purpose of helping to manage all those disparate groups to ensure they’re all pulling in the same direction.

The Asian Carp Regional Coordinating Committee has been a huge player in this realm, helping to organize its members groups who consist of some of the largest agencies in the United States—the Environmental Protection Agency, the Army Corps of Engineers, the US Geological Survey, the US Fish and Wildlife Service, the National Oceanic and Atmospheric Administration, and a host of state and provincial natural resource agencies.

But joining these groups are other transnational bodies like the Great Lakes Commission and the Great Lakes Fisheries Commission that have been at the forefront of Great Lakes science and health initiatives for decades upon decades.

And it’s been this level of collaboration from US and Canadian officials from the top on down that I found so uplifting. It was Kevin Irons from the Illinois Dept. of Natural Resources who first indicated to me that the idea from the beginning of the Asian carp crisis was that agencies chose to use this as a moment of deeper recognition that this kind of cross-border collaboration on invasive species was only going to get worse, and so building best practices for dealing with these issues in the future—“building beyond carp,” as he put it—was mission critical.

Now, when the next invasive comes along, the kind of silos that have traditionally restrained agency knowledge have weakened a bit, as people have seen how flexible and nimble they need to be to respond as quickly as necessary. They’ve also learned to ask for help, which is no easy thing for most government agencies to do.

You traveled far and wide to get a firsthand look at the carp crisis, at one point even accompanying fishermen. How did these on-the-scene experiences inform the way you wrote the book?

They were hugely important. Before I wrote Overrun, I had written a number of magazine and news articles about them [carp], and I think the impulse from my editors when they reviewed the material and Googled “Asian carp” was to see videos of leaping fish and think it was a bit of a joke in some respects. And a bit of distance from the topic makes that easier to stomach.

But when I set out to write the book, I knew that beyond a basic journalistic best practice of getting out into the field and talking with people, I had to get a firsthand sense of as many facets of the Asian carp story as possible. Part of this is because I was writing the book as a piece of creative nonfiction, and creating scene and story around lived experiences (my own and others) was essential.

And part of this was self-serving, to be honest. Telling people I was writing a book about Asian carp would usually yield looks of bewilderment. “You’re writing a book about fish?” was the common reply. But as I allude to in the introduction, I tried my best to follow the story and the history and the narrative as far as it would take me in numerous directions.

In this way, in writing the story about Asian carp in North America, it quickly became necessary to understand Reaganomics; how the Late Wisconsin glaciation impacted the formation of the Great Lakes; how horticulture approaches complex ecological problems; the evolution of “invasion biology” as a discipline and the various factions in that scientific field; environmental DNA; and the hydrologic functioning of the Illinois and Chicago rivers. It’s all connected!

And so when I tell people Overrun is a book about fish, the caveat is that Asian carp, in many respects, are simply a convenient lens to understand some of the most pressing ecological dangers we face in North America at this time and the historical context from which they emerged.

Yet I never would have felt this as deeply as I needed to had it not been for those days on the river, or that afternoon in the processing plant, or those mornings in the lab.

At one point in the book, a resource economist you speak with wonders if managing carp is based not necessarily on the most effective method, but on financial decisions by governments. For example, it costs less money to fish down carp and more money to fund engineering projects—but big projects can command bigger budgets and more attention. From your observations in writing the book, how important do you think such financial decisions were in evaluating carp management methods, and did such decisions get in the way of choosing the most effective methods?

When federal and/or state tax dollars are needed to fund the short- and long-term projects to halt an invasive species, politics can’t help but play a role in how it’s handled.

Given that I live on the shores of Lake Ontario, I went into writing the book wearing Great Lake-tinted goggles, assuming it was good and right for the lion’s share of resource dollars to flow into stopping the fish from reaching the Great Lakes. But travelling beyond the Great Lakes basin helped me appreciate not only the importance of keeping Asian carp from the basin, but that our way of thinking and our politics had created an entire framework to think about the crisis in North America, breaking the continent up into zones we could save and those we could not, typically because the fish were already present.

This was especially true the further I travelled in the American South, where academics and resource officials I met kept expressing their frustration at how federal dollars to fight Asian carp never seemed to make it to their neck of the woods. I was shocked when at a meeting of an environmental organization in Louisiana, which had small pockets of money to distribute for local initiatives, that a representative from the Army Corps was pitching them for money to study some facet of the Asian carp crisis. This is a federal agency!

What it all means is that choosing the most effective method for fighting Asian carp has often taken a back seat not only to politics and how money is allocated by Washington to be spent, but in what politicians think the public will tolerate paying for. So one may think hydrologic separation at a cost of several billion dollars over a decade or two is the best way to halt Asian carp and other invasive species, but many people have reached the conclusion that regardless of how effective it could be, the idea is simply not saleable to the public.

So what do we get in its place? Small-ball solutions like paying commercial fishers, which, as I argue, is perhaps the single most effective method we’ve found to date to curb carp numbers. And it costs us a fraction of what hydrologic separation would. Yet it’s a constant trade off for politicians and resource managers to find the balance between what is effective, what is cost effective, and what the public will stomach.

In some respects, the story of the Asian carp resembles the invasive species kudzu, which has grown out of control and overcome other plants, particularly in the southeastern US. Do you think carp could overcome aquatic life in major waterways if they are not controlled? What are the best current strategies for managing carp so they don’t get out of control?

The science seems to overwhelmingly suggest that Asian carp have quickly become one of the most dominant species in the waterways they inhabit. Using rapid breeding and opportunistic feeding habits, they’ve managed to outcompete most native fishes, with some reports suggesting that fishes in rivers filled with Asian carp often struggle to grow past 16 inches, suggesting many don’t make it to adulthood. Carp have come to represent 90-plus percent of all biomass in some rivers they reside in.

So there’s not much debate about whether they will overcome aquatic life in waterways. The only question is whether they can replicate the success they’ve had in major rivers in bigger, colder water bodies like the Great Lakes. Even here, though, a lot of recent research has suggested they would be able to locate the necessary spawning rivers and, because of silver and bighead carp’s ability to eat a broad range of phyto and zooplankton, they should have no difficulty finding sufficient food to eat. Once they’re in, they’re pretty much in for good.

We’ve had a lot of ideas for how to manage their populations—the issue has often been whether we’ve wanted to find the money to test out potential solutions in lab and in the field before deploying them. So we know that fishing their numbers down can control populations, but we also know that relying on human consumption as a population check is a fraught plan since building a market around a fish the federal government has blacklisted is generally not a sound business model.

And we have the research to suggest there are technological solutions to the crisis as well, but scale here is crucial. Sound deterrence, carbon dioxide barriers, pheromones—all have shown tremendous promise in constraining carp movement in small, closely defined areas. And if we use those in concert with eDNA testing and aggressive fishing of carp during winter when they aggregate in smaller spaces, we stand a chance of making a serious dent in carp numbers. So the best strategies we have are often stuck in laboratories, or fail simply for lack of funding. As I heard time and again, this is more an issue of social will than science. We know what works, we just need people to pay for it to happen.

The story you tell demonstrates the interrelationship of species, climate, and the environment. What can the Asian carp crisis generally teach us about solving even larger ecological problems?

I think what the carp crisis can teach us is how far we need to go in thinking through complex, large-scale ecological issues.

Here’s what I mean by that. In response to the Asian carp crisis, we began tackling the problem in small-scale, social ways—public awareness campaigns around not using Asian carp as baitfish, say, or trying to drum up support for eating them to curb their populations. Then we had to start thinking about the regulatory changes necessary to stop them, things like modifying the Lacey Act to outlaw their transportation or funding agencies like the ACRCC to oversee the problem. But it was fine, because we were relatively good at these levels of problem solving.

The further up the chain of complexity we go, the more we struggle. As soon as we start debating things like infrastructural solutions to halt the fish, the knives come out and state sues state while industries attack environmental groups. It got ugly.

And eventually, if we are ever going to solve the Asian carp mess we’ve gotten ourselves into, we need to think about things at the conceptual level and begin answering questions like “What impact is a warmer, wetter Midwest going to have on invasive species populations?” and “How have centuries of urban design and farming practices created a perfect storm for invasives to thrive?” And these are the questions we need to consider before asking ourselves the even more challenging questions around how we intend to reconsider the design of our urban areas and how we grow our food.

These are very, very difficult questions to answer, and implementing whatever findings we come back with could take decades and untold amounts of money. Yet we’ve put off reckoning with these top-tier, deeply conceptual questions regarding the Asian carp crisis for decades, focusing on the easier-to-solve issues that, while important, pale in comparison to these big picture issues.

I’d say that what the Asian carp mess can teach us about solving other ecological crises is that we can never escape these tougher, top-tier questions.

And we defer answering them at our peril.

Barry Silverstein

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