Retreat from invasion biology becomes a stampede

The New Wild by Fred Pearce (1) is the third book to be published in three years which challenges the conventional wisdom that native species are inherently superior to non-native species and the closely related corollary assumption that all non-native species are competitors of native species.  These are the assumptions that underlie invasion biology.  Each book has been progressively more pointed in its criticism of this ideology, masquerading as a scientific discipline.

Rambunctious Garden

Rambunctious GardenThe first book to be published in 2011—Rambunctious Garden by Emma Marris (2)—was timid in its approach in comparison to The New Wild.  Ms. Marris visited “restoration” projects all over the world.  She described unsuccessful efforts to eradicate non-native plants and animals as well as extreme attempts to “rewild” that are often a mishmash of plant and animal species from different native ranges and time periods.  She implied that these projects were futile as well as artificial, but she was not explicitly critical.  Despite her cautious approach, she has been subjected to intense criticism from both academics and practitioners of invasion biology.   The following excerpt of a reader’s review of Marris’s book found on Amazon.com is typical of the criticism:

“Earth as cookie jar”

“Emma Marris, the author of Rambunctious Garden (RG), loves the nature hiding in back street alleys and along the highway median strip. Marris believes it’s time to abandon (or de-emphasize) what she sees as outdated and naïve conservation strategies such as creation of national parks and wilderness reserves. She feels the biggest obstacles to a bold new world of “designer” and “novel” ecosystems is the “wilderness cult” that naively wants to preserve “natural” landscapes–which she says do not exist anymore.

Marris espouses the anthropocentric perspective that the Earth is more or less a resource cookie jar for humans–to be used carefully to be sure–but she doesn’t really question whether ethically or ecologically this is ultimately a good idea…

However, by moving the goalposts to vacant city lots as an acceptable desired future condition of the landscape, she implicitly, if not explicitly, provides cover for all manner of environmental degradation.”

Most of the 35 readers’ reviews about Rambunctious Garden on Amazon.com are equally critical.  This particular review was rated as “helpful” by 141 other readers and 21 comments were also posted in support of the critical review.  Marris and her book have been thrashed in many other venues, including conferences where she is called out by name as an enemy of nature by invasion biologists.

Where do camels belong?

Where do camels belongThe second book, which challenges the assumptions of invasion biology, was published in September 2014.  Where do camels belong? by Ken Thompson, a British academic, (3) is much more explicit in its criticism of invasion biology.  One of its strong suits is the examples of the ambiguity and absurdity of the often muddy distinction between native and non-native.  As we might expect, this distinction is less clear in Britain because it has a much longer history of “invasion” than North America (only because invasion biologists have chosen to define “native” in North America as any species that precedes the arrival of Europeans).  Professor Thompson offers some comic examples of how status as a native has been conferred in Britain and the contortions that are required to provide preferential treatment to these “natives.”

Despite kicking up the level of criticism of invasion biology a notch, reviews of Professor Thompson’s book are far more positive than those of Ms. Marris’s book.

The New Wild


Pearce
The New Wild was published in the US in April 2015.  Fred Pearce does not pull his punches in The New Wild.  He methodically lays out all the reasons why invasion biology no longer deserves the status of a scientific discipline.  The readers of Million Trees are familiar with all of these arguments, so we will summarize them here and provide links to articles on Million Trees that illustrate each issue:

Although The New Wild is a full frontal assault on invasion biology, it has been very favorably received by reviewers on Amazon.com.  Here is a review by a reader for whom the book was an epiphany:

“An important—even essential—look at our global challenges”

“Let me cut to the chase: read this book. I want to follow that statement with several exclamation points, but I’m trying to control my enthusiasm. Perhaps the book seems so important to me because I was so ignorant when I first started reading it. Perhaps my level of ignorance is extraordinary, but I just checked the websites of several environmental organizations I respect and it looks to me like they too need to read the book. Certainly it is provocative, controversial, and challenging. It will anger some, but it is not an ad hominem attack against anyone. Whatever you think of Fred Pearce, Daniel Simberloff, and others on either side of this debate, it is clear that the debate is important, even urgent. It made clear to me that I have put too much faith in environmental organizations to ferret out the facts and explicate the issues for me. Clearly, I have allowed myself to be misled. Even more important, scientific standards are not being rigorously followed. Have you noticed the headlines about all the “invasive” species that “need” to be eradicated? About the billions of dollars that are required to do this purportedly important work? I have been asking why so much killing is necessary. Pearce states that it isn’t. In fact, he goes further and suggests that the species targeted for eradication may be our salvation precisely because they have the adaptability and resilience to survive in environments disturbed and dramatically changed by mankind. His arguments are articulate and persuasive.

Environmental writers and organizations sometimes make conclusory and inflammatory claims about the damage done by those species they choose to characterize as invasive. And supporters such as myself accept those claims unquestioningly. As Pearce points out in his eye-opening treatment of the subject, too often one environmentalist repeats or even amplifies the unsubstantiated claims of another, and when this happens again and again with no one questioning the science along the way, dangerous, counterfactual conclusions are spread and soon become gospel. Pearce’s probing, incisive exploration into several of those claims in his seventh chapter, “Myths of the Aliens” is alone worth the price of the book.

Pearce woke me up. I respect the scientific method and believe it must be adhered to without fail in environmental writings. I have naively accepted that other environmentalists feel the same. We cannot make intelligent decisions if we are uninformed about true facts. False allegations have no value for any of us. “Invasive” species need new, clear-eyed, unbiased consideration by environmentalists. We need to look again at our underlying assumptions. What does “native” really mean? Which species are natural to an area? Which can survive in the “wild”? Pearce asserts that there is a “New Wild” and that we will do better to respect it sooner rather than later, to work with it rather than against it. I learned so much from Pearce not only about the facts of our situation, but also about new ways of looking at our extremely challenged world. I highly recommend this book and hope you get the opportunity to read Pearce’s insightful and creative ideas.”

This reader understands for the first time that the environmental organizations he/she had previously trusted had misled him/her into believing that non-native species are the cause of environmental damage rather than symptoms of that damage.  He/She was always uncomfortable about all the killing that was motivated by that viewpoint, which is perhaps what opened his/her mind to Pearce’s message.  This sequence of realizations describes my own journey to the other side of invasion biology.  I was initially appalled by the killing, but I did not realize that the justification for the killing was entirely bogus until I began to do my own research.  I initially assumed that they knew what they were doing.  After reading innumerable books and studies, I began to understand that there is little evidence supporting their claims that non-native species are damaging the environment.  Quite the opposite is true.  We hope that Pearce’s book will start many other readers on the same journey of discovery.

(To be fair, the first critique of invasion biology was Invasion Biology:  Critique of a Pseudoscience by David Theodoropoulos, published in 2003.  Although it was ahead of its time, virtually every criticism of invasion biology in that book remains true to this day.  However, at that point in time there were few empirical studies testing the hypotheses of invasion biology and few “restorations” based on those hypotheses.  It was therefore more difficult to make the case against invasion biology.  Theodoropoulos foretold the fate of invasion biology as a discredited ideology based primarily on his personal observations in nature.)

Progress!!

In just three years, three hard-hitting books have been published which confront the unfounded assumptions of invasion biology.  Although each book is progressively more aggressive and explicit in its criticism, the reaction of the public has been progressively more positive.

We admired all three of these books, so we are reluctant to conclude that the more favorable reaction to the more recent books is because of improved quality.  Perhaps the more explicit criticism of the more recent books makes it easier for readers to appreciate the strength of the argument.  Although we are deeply grateful to Emma Marris for leading the way, Rambunctious Garden requires the reader to reach the conclusion she only implies. The New Wild makes no such demands on the reader’s judgment.

However, we have our own optimistic theory about why readers are welcoming The New Wild.  The more experience the public has with the destructive projects which attempt to eradicate non-native species, the more likely they are to understand the futility and the damage being done to the environment.  We choose to interpret the positive reception for The New Wild as an indication that the public is ready to abandon the fantasy of returning our public lands to some mythical ideal landscape.


  1. Fred Pearce, The New Wild, Beacon Press, April 2015
  2. Emma Marris, Rambunctious Garden, Bloomsbury, 2011
  3. Ken Thompson, Where do camels belong?, Greystone Books, 2014