Is Rewilding a Good Idea? Why We Need to Rethink Our Approach to Ecosystem Regeneration

Rewilding is a popular idea nowadays. Given the poor performance of humans in managing ecosystems, the temptation to leave the wheel to Gaia is strong. But it is also true that in the long history of the Earth, Gaia has not always been firmly in control. Maybe she was drunk, maybe she was stoned, but Earth without humans has been "wild" in the sense that it went through all sorts of oscillations -- sometimes true catastrophes. Just think of the alternance of ice ages/interglacials of the past 2-3 million years. So, what do we mean with "rewilding"? Returning Eurasia to the "Mammoth Steppe" of the ice ages? Or to the lush forests of the Eocene? Or what, exactly? Here, Helga Ingeborg Vierich criticizes the concept of rewilding and proposes better ideas to manage the ecosystem. In general, the correct approach should not be "rewilding" but "regeneration"

By Helga Ingeborg Vierich -- From "The Proud Holobionts" Forum

Is the term we are looking for here really "re-wilding”? I ask this because the term “wild” implies that it is not “tame” - “wild” is usually present as the opposite of “domesticated”.

The term further prevents an understanding of reality. What is that reality? Well, let us start with this: the human species IS part of the ecosystem of this planet.

Homo sapiens and earlier ancestral forms have been keystone species for at least a million years. For 99.99% of our evolutionary history, we humans were keystone ecological engineers. Like beavers and otters and wolves and whales and elephants, we were increasing and stabilizing the diversity of life in every ecosystem we inhabited.

This positive effect on ecosystems was not, however, due to anything genetic or innate in human behaviour, it was due to learned and shared patterns: in other words, it was “cultural”.

Starting in a few places on the planet, a cultural change to more ecologically destructive economies changed all that. At first it only effected a tiny proportion of humanity and of the ecology of the planet, but then it grew and coalesced into larger and larger cultures containing higher and higher proportions of the human beings, and more and more surface areas around the globe.

Today we call it our “civilization” as if it was a positive and progressive change in our relationship with the planet and each other.

It has been nothing of the kind. Each state level society with civil - urban - population concentrations, has been requiring far too much deforestation and other resource extraction. The reality is that there is nothing positive about the progressive destruction of ecosystems in support of greater and greater urbanization and an extremely expensive (though tiny) “upper” class of humans.

This has not just disrupted the positive trophic flows that characterized the human past, after the “industrial revolution” began, it has reversed them. Now, the global industrial economy is the main driver of species extinction, environmental pollution with toxins and plastics, and climate change.

Just look at this chart below...

So our job now is NOT to “leave nature alone” but to relearn our species' responsibility within the planetary ecosystem, and RENEW that positive effect on diversity and stability.

Humans will not be able to do this if they continue to be guided by corporate and political elites whose main goal is to enrich themselves and stay “in power” over inegalitarian cultures competing for control of the planet’s diminishing resources of minerals, fossil carbon, water, and “arable soil”. I am very afraid that what this means is incomprehensible to most people in this present industrial and financially-driven culture.

1: Stop industrial agriculture. The planet cannot afford it. 

2, Restore predators and critical keystone species to every available habitat, and stop killing them for “fun” or “profit”. Beavers, wolves, lions, bison, bears, caribou, otters, and all the other component species of a diverse and healthy ecosystem will restore positive trophic flows. That includes diversity of plants, and is vital: 

3. Stop the destruction of forested ecosystems: the lumber and paper industries must be radically scaled back. Stop this silly substitution of “commercially valuable” tree plantations and restore actual forest ecosystems. Above all, immediately stop the cutting down of existing forest ecosystems. Recycle paper, plastic, all metals, and so on. 

4. All industrial scale “commercial” fishing, as well as “fish farming” must be stopped. 

5. TAX the rich and the corporations - and stop all investment of money (gambling) in any industry.

6. Begin taking the necessary steps to close down the petroleum-powered automobile industry: no more ”new models” every year. Restore and enlarge electrically powered public transit - trains and street cars and buses... encourage bicycles by increasing bike lanes in all towns and cities.

Trophic Rewilding: A Cure for a sick Planet?

 

The Mammoth Steppe was a huge area that extended over most of Northern Eurasia, including part of Alaska. It existed during the last glacial period, 126,000 YBP–11,700 YBP. Then, it was superseded by modern boreal forests during the thaw that led into the Holocene. The question of what factors led to this huge switch in the dominant biome is far from being clear. If "rewilding" some areas of the Earth is a good idea, should we strive for forests or steppes? After all, they are both "natural" environments?   

You may have already seen this paper just appeared on "Nature" with the title: "Trophic rewilding can expand natural climate solutions." The study is led by Oswald Schmitz of Yale University and is an assessment of the role of natural trophic chains on climate and of the perspectives of using "rewilding" as an important method for the mitigation of global warming. It has been described as a "landmark paper," and in several respects, it is. It is part of a general movement in favor of rewilding, and there is even a "Global Rewilding Alliance." 

The concept makes plenty of sense. It provides an alternative to the multiple bizarre ideas that have been proposed as "solutions" for the climate change problem, including cutting down the Boreal  Forests to increase Earth's albedo. On the other hand, it is still a subject in its infancy. One problem is that the authors do not mention that there is not just carbon sequestration at play in the climate game. They miss the effects of forests on the hydrological cycle (the kind of effects studied by Gorshkov, Makarieva, and others). But I think that it could be possible to merge these concepts together. In both cases, the idea is to restore the ecosystem to its maximum metabolic rate, balancing the disturbing effect of human activities. 

A deeper problem lies in understanding why exactly trophic chains have the effects claimed in the paper. The paper reports several estimates of the amount of carbon stored by various biomes, noting how it increases when a more diverse ecosystem is restored. To give an idea of the approach of the paper, the authors write that: 

The dividend of creating dynamic landscapes and seascapes is illustrated by the 1.2 million Serengeti wildebeest still found in Africa. This population annually migrates throughout the 25,000 km2 savannah– woodland landscape tracking lush vegetation created by seasonally and spatially varying rainfall. During the migration, wildebeest consume large amounts of grassland carbon and return it as dung that is incorporated by insects into soil storage. In the early twentieth century this dynamic was halted when the wildebeest population plummeted to 300,000 animals, decimated by rinderpest disease transmitted from domestic cattle. Consequently, there were too few animals to fully graze the landscape. The increased standing grass fuelled more frequent and intense wildfires that released carbon stored in the biomass across 80% of the landscape, which rendered the Serengeti a net source of atmospheric CO2 (ref. 47). Similar alterations of fire regimes followed the near-prehistoric extinctions of other large herbivores, the legacies of which persist today. Fire is an essential natural process in most of these systems, but the loss of natural grazing increases their frequency and intensity. Restoring the wildebeest population through disease management led to less frequent and intense wildfires, and gradually restored the Serengeti back to being a carbon sink. The Serengeti now stores up to 4.4 MtCO 2 more than when the wildebeest population was at its lowest. 

Which is truly fascinating. But why exactly should more diverse ecosystems store more carbon? One could say that if there were no wildebeest, then the forest would cover the Serengeti Park, and wouldn't a forest store more carbon than a savanna? Not necessarily. Large herbivores can sequester a lot of carbon in the soil, and it seems that the deep, fertile soil that Europeans found in the central area of North America was the result of the work of the huge herds of large ungulates living there. So, in terms of carbon storage, is a forest better than a savanna, or is it the reverse? 

Probably there is no clear-cut answer, and maybe there will never be one. Biomes are always dynamic; they change all the time. Although, in general, the ecosystem strives for stability, it may not be able to reach it except as an average -- it is sensible to even minor triggers such as the Milankovich oscillations that triggered the cycles of ice ages of the past two million years or so. But the Milankovich effects are just that: triggers. For the huge Earth ecosystem to move from a cold to a warm status, and the reverse, it takes enormous forces at play. In any case, the trophic chain remains the crucial factor in the ecosystem, the backbone of holobionts in their extended definition.

h/t John Day and Михаил Войтехов