Botkin Chapter 2: Why the Elephants Died

Sharon is busy with schoolwork this week and has asked me to pinch-hit on the virtual pub book discussion blog (my choices are Kat Anderson or Hugh Raup for book #2). If this is your first visit here, the best place to start — and to introduce yourself — is:

The focus of this chapter is the disparity between computerized model predictions of wildlife populations over time, their actual populations, and why these numbers are usually so different from one another. This is an important distinction because most of our fish and game management objectives are based on the former, inaccurate, “balance of nature” computerized numbers, as are many of our Endangered Species population estimates. Botkin also provides a brief parallel history of ecology as a science, which concludes with one of my favorite quotes in the whole book:

“Many believe that ecology is still a “young” science, but in comparison to most modern sciences, it is not young but simply retarded.”

This chapter examines the truth to that statement by comparing elephants in Africa, anchovies in Peru, salmon in the Pacific Northwest (where I had the pleasure of working under Botkin and participating in the first of his studies of that animal), and whales in the ocean, with fruit flies in a jar. Botkin’s examples and thoughts are clearly presented and described in well written English, with little use of Latin, metrics, or acronyms; i.e., “Plain English.” As a result, almost anyone with a basic education and good reasoning skills can follow his logic, arguments and conclusions.

The chapter opens with the story of one of the world’s first protected wildlife populations, the elephants of Tsavo; a large 5,000-square mile national park in Kenya, Africa dedicated to the survival of African big game animals. The park was created in 1948, 65 years ago, largely through the efforts of a single man, David Sheldrick, for the protection of declining African elephant and rhinoceros populations from their principal predators: human ivory and meat hunters. The primary purpose for protecting these animals was to attract tourists to the park in order to view them. Within 10 years the elephant herd had increased to 36,000 animals and the landscape had become largely denuded of vegetation. By the mid-1960s it was decided that 3,000 of the animals needed to be shot, in order to preserve the habitat. This idea was overturned and the decision was made to “let nature take her course” and allow the elephants and vegetation to achieve a “naturally balanced” “carrying capacity.” A prolonged drought in 1969-1970 contributed to the destruction of most of the remaining vegetation and an estimated 6,000 elephants starved to death.

Botkin uses this story to illustrate the difference between a theoretical balance of nature, and a balance created by people; i.e., roughly the difference between shooting 3,000 elephants and letting 6,000 elephants starve to death. A third alternative is also considered – that Tsavo was simply too small to contain that many animals and that they needed to migrate from one area to another during times of drought or other stressors. Following Sheldrick’s death in 1977, poachers again entered the preserve and by the 1980s the herd had been reduced to 6,000 animals. Today it stands at about 12,000 – far less than the 36,000 that had once lived there under Sheldrick’s management practices.

The elephants of Tsavo are used as a beginning point to examine other human attempts to manage the environment to achieve a desired number of animals. The wildly fluctuating populations of Peruvian anchovies, Pacific sardines, Atlantic menhadens, and several other commercial fisheries are provided as examples where harvest levels were established in attempts to stabilize populations, and failed; typically resulting in abrupt declines in the targeted species. These failed attempts at controlling natural populations of desired fisheries were based on scientific models. This is an important consideration because much of the world’s food supply – particularly in poorer countries – is provided by fish.

This is the principal theme of Chapter 2: the consistent failure of scientific predictive models to accurately estimate wild animal populations, and the reason that Botkin concludes ecology is “retarded” when compared to other modern sciences. He begins in 1838 with Pierre-Francois Verhulst’s simulation of natural populations with the invention of the S-shaped logistic growth curve, which results in a conceptual “carrying capacity” for the environment. Laboratory experiments in the 20th century replicated this model with certain insects and with bacteria, thereby seeming to prove its utility for wild fish and elephants. Alfred Lotka, an early mathematical ecologist, used fruit flies, bananas, and aquariums to fine-tune this equation, and was able to maintain stable populations of these animals in controlled environments. This artificially regulated number of insects was termed a “density-dependent” population, Lotka’s equation was named the “logistic” model, and Botkin cites a paper written in 2010 that examines this potential phenomenon in regards to wild elephants.

As Botkin next explains that, although the logistic equation is considered an “ecological formula,” its mechanical basis can be compared to “a collection of identical colliding balls” with “a certain rate of destruction” and “capable of identical rates of division.” In using this equation to consider a herd of elephants there is no differentiation between bulls, calves, or breeding cows, for example, just a total number, as with the box of identical balls. This idealized balance of population numbers cannot (“has never been observed to”) occur in nature, of course, and Botkin describes the logistic equation as “something from [Lotka’s] imagination, not from actual observation” – as occurred with the world fisheries or the Tsavo elephants.

Following the widespread adoption of Lotka’s work in the field of ecology, Botkin goes on to describe how it has evolved into a simple calculation that is exactly ½ as large as predicted carrying capacity: the “maximum-sustained-yield” population. To complicate the picture further is the fact that it is impossible to accurately measure many wild populations in the first place – Botkin uses Arctic crabs and the television show Deadliest Catch as his example, and comes to the conclusion that the maximum-sustained-yield concept is “fundamentally flawed.”

The Marine Mammal Act of 1972 tried to overcome this broken model with a new concept: “the optimum sustainable population,” and Botkin was hired to help develop this idea. His approach was overturned, however, and a panel of University of Washington scientists recommended a return to the failed logistic model and reinstituted the ideas of “maximum productivity” and “carrying capacity.” This led to Botkin’s conclusion that the scientists had reverted to a belief in the disproved myth of the “balance of nature,” and subsequently led to his book Discordant Harmonies, and ultimately to this present work:

“Thus even today, in both law and in practice, the scientific conservation of endangered marine species continues to be based on the idea that nature undisturbed is constant and stable . . .”

In other words, the management of endangered whales is based on computerized mathematical formulas developed with fruit flies in an aquarium, and not on actual observations by people:

“An irony is that it seems that everybody talks about how complex nature is . . . but we are content to formalize nature in about as simple and simplistic a way as possible.”

2 Questions:

Botkin argues that it is important that people – and particularly scientists – must accept the contradictions between fact (“observations”) and theory (“computer models”). Agree or disagree?

He further argues that this acceptance will lead to a “deeper level of thought” and allow us to find a “true harmony of nature.” Does that even sound plausible or necessary?


About Bob Zybach

PhD in Environmental Sciences. 5th-generation Oregonian. Likes music.
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4 Responses to Botkin Chapter 2: Why the Elephants Died

  1. TreeC123 says:

    This may be new to some but there is a continuous thread of “systems science” in the ecological literature that explains living systems as “open systems, far from equlibrium.” The equilibrium models are (like all models) wrong, but they are not useless. The fact that policy gravitates toward equilibrium models is that they lend themselves to prediction, whereas non-equilibrium systems are on the “edge of chaos” (a technical term, it does not mean random).

    Equilibrium models are just approximations that allow observers to make certain kinds of generalizations while recognizing that there are many forces that push ecosystems away from equlibrium.

    Real-world ecosystems are self-organized, non-linear, evolved to exploit environmental gradients that are always shifting. There may be multiple pseudo-equilibria, or “basins of attraction.”

    It may be useful to review E. J. S. Hearnshaw, R. Cullen and K. F. D. Hughey. Ecosystem health demystified: An ecological concept determined by economic means.

  2. Bob Zybach says:

    Tree: If you are going to continue to presume lecturing the rest of us with your comments, can you at least please tell us who you are? I don’t know about others, but I am not going to bother taking the opinions or recommendations of an anonymous “expert” very seriously if they can’t even bother to say who they are. Might just as well spend my time listening to television commercials.

    Also, it would be good to stay on topic. Before recommending readings to others on this blog, how about you reading Botkin’s chapter 2 first and commenting on that, instead? Please see the link in paragraph one of this post and consider adding some actual credibility to your thoughts.

  3. gildehuff says:

    Let me begin with a quote from Aldo Leopold: “It is a conspicuous fact that the corn stubbles selected by geese for feeding are usually those occupying former prairies. No man knows whether this bias for prairie corn reflects some superior nutritional value or some ancestral tradition … If I could … I might soon learn the reason for the prairie bias. But I cannot, and I am well content that it should remain a mystery. WHAT A DULL WORLD IF WE KNEW ALL ABOUT GEESE.” (emphasis added – p22, “A Sand County Almanac with Essays on Conservation from Round River”, Ballantine Books ISBN 0-345-34505-3)

    Mankind, in my opinion, has an obligation to learn as much as possible about this world but mankind also needs to be patient and accept that mankind is not God and therefore mankind is incapable of knowing everything and must build knowledge by slowly establishing what is fact as opposed to desperately grasping at straws.

    Re: “Botkin argues that it is important that people – and particularly scientists – must accept the contradictions between fact (“observations”) and theory (“computer models”). Agree or disagree?”
    Agree but:
    –> “must” is the wrong word here. “Must” implies that we have no choice. Obviously we have a choice. There will be many who choose to ignore reality whether it is because of pride, wishful thinking, lack of concern for their future and much less for the future of others, selfishness, questions about the motives and knowledge of those who proclaim what is truth, willful ignorance or because of insufficient mental prowess.
    –> Maybe we should rewrite this to say: ‘It is important that people – and particularly scientists – should understand that contradictions between facts (“observations”) and theory (“computer models”) require that the theory be either abandoned totally or suspended until it can be refined later as more facts become available. The bible says that knowing what is right and not doing it is sin (James 4:17). The sin is bringing/allowing harm where harm didn’t need to occur. To pretend that you have the answer when you don’t is sin.
    –> Any scientist who holds to a theory which has been contradicted by observations, is (by definition) not a scientist. Instead, that person is either a snake oil salesman trying to con others for their own advantage or they have been blinded by their pride.
    –> Aldo Leopold said it very well in his essay “The Upshot” when he said: “Conservation is paved with good intentions which prove to be futile, or even dangerous, because they are devoid of critical understanding either of the land or of economic land-use” (p263, “A Sand County Almanac with Essays on Conservation from Round River”, Ballentine Books ISBN 0-345-34505-3). Many of those who worship Mr. Leopold seem to have been selective readers.

    Re: “He further argues that this acceptance will lead to a “deeper level of thought” and allow us to find a “true harmony of nature.” Does that even sound plausible or necessary?”
    –> It is not plausible nor is it necessary. Thinking that mankind can find a “true harmony of nature” is arrogance for that would require a perfect mankind. Mankind is free to destroy whatever mankind wishes either willfully or in ignorance. Necessity only enters the picture when mankind puts ego aside and accepts the responsibility to discover what is right and then work towards doing that right. That requires that mankind be willing to accept failure when facts/observations disprove formerly accepted theories. Only then will it be plausible for mankind be able TO BEGIN TO DRAW NEAR to a constantly changing “true harmony of nature”. Only then will mankind be able to be at one with the will of God.
    –> Science is the means to a “deeper level of thought”. Thought, no matter how deep, will always fail us if it is contradicted by facts whether they are already discovered or yet to be discovered.

  4. Bob Zybach says:

    Gil: Thank you for the detailed and thoughtful response. The word “must” was taken out of context to some degree, but your point is very well taken. I consider myself a somewhat spiritual person rather than a religious man, but I am in total agreement with many Christian concepts and perspectives — which are in complete harmony with those of many other religions as well. I’m not sure that we were “put” here, for example, but now that we have arrived I think we have real ethical, practical, and moral reasons to be good stewards of the land and its resources — and science is a wonderful tool for trying to achieve such goals. And that is just one example of many.

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