Conservation Sense and Nonsense

The Anthropocene vs. The Doomed Earth

On Saturday, September 14, 2013, The New York Times published an op-ed by Erle C. Ellis entitled, “Overpopulation Is Not the Problem.” Professor Ellis challenges the conventional wisdom that the future of the Earth is threatened by an inexorably increasing human population. He tells us that emerging knowledge of the history of human civilizations should reassure us that humans have altered ecosystems for 200,000 years to meet their needs and there is no reason to believe there is a limit to the ability of humans to continue to manipulate our environment as needed to support a growing population.

Little of human history is recorded. Therefore, only recent discoveries of archaeologists have informed us of the many technological advances of human civilization that increased food production. Irrigation and agriculture, for example, is a relatively recent human accomplishment. In the Old World, humans have supplemented their diets by raising domestic animals in the past 6,000 years. This knowledge only reached the New World with Europeans in the 16^th century.

Professor Ellis suggests that our appreciation of human adaptability is based on our knowledge of the history of human accomplishment. That knowledge is not only relatively new, but is not yet widely known by the public. He admits that he, himself, did not comprehend human adaptability until studying agriculture in China, where human ingenuity has managed to keep pace with the growth of the most populous country on Earth. His work is now as informed by archaeology, geography, and economics as it is by his original discipline, biology.

We introduced Professor Ellis (University of Maryland, Baltimore) to our readers in an article about the globalization of ecology by humans. He is one of the proponents of naming a new geologic era, the Anthropocene, to acknowledge the fact that the activities of humans have altered the Earth in significant and profoundly important ways. He does not find reason to despair about our impact on the Earth:

“The only limits to creating a planet that future generations will be proud of are our imaginations and our social systems. In moving toward a better Anthropocene, the environment will be what we make of it.” (1)

At the opposite extreme: The viewpoint of Jake Sigg

At the opposite extreme of Ellis’ rosy view of the future of the Earth and its human occupants, we turn to Jake Sigg’s “Nature News.” Regular readers of “Nature News” will find the following example of Sigg’s pessimistic view of the future of the Earth typical of his viewpoint:

“My vision for the world is increasingly apocalyptic. Lest you think I’m being overly dramatic, with the type of economic/political system we have, things can only get worse, not better, and the horror and chaos of Syria, Egypt, et al could be easily foreseen–not in detail, but in general, as the result of too many competing for space and resources. I expect lots of horror stories in the future, and I hope I’m dead by the time it hits me directly. At the pace things are moving, I may not be that lucky.” “Nature News,” September 7, 2013.

Jake Sigg’s concern about over-population also motivates his extreme opposition to immigration, including legal immigration.

Finding Common Ground

As diametrically opposite as these viewpoints seem on the surface, they actually share common ground. As Professor Ellis says, “The science of human sustenance is inherently a social science.” In other words, the famines that humans have experienced were as much a failure of the social system as they were of the physical limitations of the planet to provide adequate food. Jake Sigg agrees that “our economic/political system” is at least partially to blame for the failure to compensate for inadequate resources.

For example, the current round of climate change has been caused by the activities of humans, but our social, political, and economic systems are preventing us from responding to it effectively. Hunger in America will be exacerbated if conservative politicians are successful in their effort to drastically reduce the availability of food stamps to the poor.

Professor Ellis is confident that human social systems will accommodate population increases. Mr. Sigg predicts the opposite outcome. The more likely outcome is probably somewhere in between. We will probably muddle through with occasional catastrophic famines where physical shortages cannot be mitigated by competent social/political structures.

Admittedly, this topic is a digression for Million Trees. It is intended as a reminder that the ecological “restorations” being demanded by native plant advocates should be a public policy decision and the failure to treat it as such has resulted in irreparable harm to our environment. It is therefore an example of how environmental problems and their resolution are ultimately failures of human social systems.

Update: Our readers might be interested in Jake Sigg’s very different reaction to Erle Ellis’ op-ed in his latest newsletter (September 17, 2013), available here. Here is an excerpt from it:

“One of the most discouraging developments of our time is the elevation of opinion to equal status with knowledge in the minds of large numbers. People who have spent their lives studying and working in a field are on equal footing with someone who hadn’t thought about the matter five minutes ago, and their vote counts just as much. Not exactly a way to build a lasting, self-perpetuating society.”

In other words, problems are caused by too much democracy, in Sigg’s opinion. He believes that “experts” should be in charge, of which he—a retired gardener in the Recreation and Park Department– is apparently one and Erle Ellis—Associate Professor of geography and environmental systems at University of Maryland, Baltimore—is not. In contrast, Million Trees values expertise, but considers the alteration of our public parks a political decision which must be made democratically. More democracy is needed to resolve these conflicts, not less.

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Erle C. Ellis, “Overpopulation Is Not the Problem,” New York Times, September 14, 2013.

“Ecological Restoration and Environmental Change”

Restoration and Environmental Change: Renewing Damaged Ecosystems was written by Stuart Allison. He is Professor of Biology and Director of Green Oaks Field Study Center at Knox College in Illinois. His perspective on ecological restorations is unique because he is both a scientist and actively engaged in ecological restoration.

There is a predictable tension between applied and theoretical science. Ecology is particularly susceptible to this tension because its application is usually considered the immediate goal of the theoretical science that is intended to inform and guide it. Therefore, we were very interested in Professor Allison’s viewpoint and we were intrigued by the suggestion of his title that his book would take into consideration the rapidly changing environment.

Although the restoration goal at Green Oaks is the re-creation of the tall grass prairie that is the historical landscape, Allison’s Ph.D. degree from UC Berkeley in Integrative Biology suggested that he is also familiar with our local ecology in the San Francisco Bay Area. In fact, he mentions our controversy regarding the desire of native plant advocates to eradicate eucalyptus in California and he uses it to illustrate his opinion of novel ecosystems.

“When I was a graduate student at the University of California, Berkeley there was (and still is) a magnificent grove of blue gum (Eucalyptus globulus) outside of the Life Sciences Building. It was rumored that they were some of the tallest blue gums in the world, growing so tall because they lacked any herbivores and diseases. Eucalyptus trees grow beside roads all along California’s coastal highways and in the inland valleys of the coast ranges. In fact, I cannot imagine California without eucalyptus trees. But, of course, eucalyptus are not native to California–the first eucalyptus was introduced to California by Australian miners coming to the Gold Rush in the 1850s. Today eucalyptus are so well established that many people think they are native to California, and even if they know they are not native, they don’t want to see them removed because to them, like me, eucalyptus are a central part of their experience of California. Some people also fear that removal of eucalyptus will lead to erosion on steep hillsides and a decline in biodiversity. In contrast, native plant enthusiasts in California would love to see eucalyptus permanently removed. The dominance of eucalyptus in California is hardly unusual for a novel ecosystem, but it stands out because the trees came from Australia and because they are so striking in appearance and aroma that they can’t be missed.” (1)

Professor Allison then acknowledges that some scientists are now interested in and respectful of novel ecosystems such as the eucalyptus forest. However, he is worried “that novel ecosystems will lead to a homogenized world in which the same species…are found everywhere.” That debate is not the central theme in his book. His primary objective is to take the pulse of his colleagues in ecological restoration and report the changes in their objectives in the past 20 years, given the rapid changes that have occurred in the environment.

What is the goal of ecological restoration?

The Society for Ecological Restoration (SER) is the professional organization recognized by most restorationists. Its Policy Working Group claims that “an ecosystem is fully restored and the project has been completed when the restoration ‘contains sufficient biotic and abiotic resources to continue its development without further assistance or subsidy.’”

Annual Prairie Burn, Green Oaks, Knox College

Professor Allison tells us that the restoration in which he has been engaged for over 20 years will never achieve that standard: “The tall grass prairie and savanna restorations I work with are all based on a return to historical pre-Euro-American disturbance, but all require perpetual management and human intervention to maintain them on the desired ecological trajectory. Without regularly applied fire, those ecosystems would soon become dominated by many woody species and grow into a woodland lacking prairie or savannah characteristics.” Professor Allison describes the annual “Prairie Burn” at Green Oaks which is considered an important social event by students at Knox College.

This is one of many ironies about ecological restorations. Many projects are attempting to re-create an historical landscape at a specific period of time, which was not the result of natural succession. In the case of grassland prairie, it was largely the result of periodic fires set by Native Americans. Left to its natural devices, grassland would soon be “invaded” by shrubs and over time it would become a forest if soil and climate conditions were suitable. In that sense, it is an artificial landscape, as unnatural as any manmade garden. That the humans who created that historical landscape were indigenous, as opposed to European settlers, seems to us a meaningless, legalistic quibble.

The “field of dreams” theory

Most restoration projects focus almost entirely on plants. Little explicit attention is paid to the animals that are the desirable inhabitants of the restoration. Restorationists believe that if the habitat is made available, the animals will quickly follow. This is the “field of dreams” theory, i.e., if we build it, the animals will come. This is magical thinking.

Restoration projects rarely monitor the results of their projects sufficiently to test this theory. In the San Francisco Bay Area, native plant advocates claim there are more birds and animals occupying restoration sites, but these are anecdotal observations that cannot be verified. Nor do they seem credible to skeptics of the projects, who often think the habitat that has been eradicated actually supported more wildlife.

Evolving goals of restoration projects

Here in the San Francisco Bay Area we have observed the changing objectives of ecological restorations. Over fifteen years ago, local projects were touted as “sustainable.” The public was told that once restored to historical equilibrium conditions, the projects would be capable of sustaining themselves without further resources.

Comparson of pesticides used by San Francisco's "Natural Areas Program" compared to landscaped areas of San Francisco's parks — Comparson of pesticides used by San Francisco’s “Natural Areas Program” compared to landscaped areas of San Francisco’s parks. Photo courtesy of SF Forest Alliance.

We no longer hear that claim. Now we are told that our “natural areas” must be managed in perpetuity. More herbicides are used in San Francisco’s “natural areas” than landscaped portions of the parks, with the exception of a professional tournament golf course. And if we want the animals that historically occupied those areas, they must be reintroduced, using labor-intensive methods.

Professor Allison observes the same “mission creep” amongst his colleagues. The goal of replicating an historical landscape is no longer the dominant theme of ecological restorations. Now the goal is more commonly defined in terms of increasing “biodiversity” and improving “ecological functions.”

New buzz words

If the new goal of ecological restorations is greater biodiversity and improved ecological functions, it seems reasonable to ask what these terms mean. Unfortunately, we were unable to find the answer to that question in Professor Allison’s book. Those terms are used as though their meanings are intuitively obvious. They are not. These terms are jargon that has little intrinsic meaning and they probably mean different things to different people.

When scientific studies quantify biodiversity, they count species of both native and non-native plants and animals. Since there are now far more species of non-native plants and animals and far fewer extinctions of native plants and animals, biodiversity has increased virtually everywhere in the world. So, as far as science is concerned, how could a restoration project that eradicates all non-native species result in greater biodiversity?

Obviously native plant advocates are defining the word “biodiversity” differently than traditional science. Native plant advocates seem to define biodiversity as exclusively native. Furthermore, the nativist ideology believes that the mere existence of non-native plants and animals will inevitably result in the extinction of native plants and animals. There is little scientific evidence to support this assumption. Few extinctions have been attributed to the existence of non-native plants and no extinctions blamed on non-native plants have occurred in the continental United States.

The term “ecological functions” is even more mysterious as it relates to ecological restorations. It could mean almost anything: production of biomass, soil composition, photosynthesis, carbon sequestration and storage, nutrient cycling, fire regime, hydrologic cycle, etc.

Professor Allison does not provide us with his definition of this term, so we will make an assumption based on our knowledge of ecological scientific literature. We told our readers about a study in Hawaii which compared native and non-native forests with respect to the ecological functions they are performing. In that study, three such functions were measured and reported: carbon sequestration, production of biomass, and nutrient cycling. The study concluded that non-native forests were performing these ecological functions as well as native forests.

We can also compare treeless grassland prairie with a native or non-native forest with respect to those ecological functions. Forests—whether native or non-native– will fulfill these and other functions at least as well as the grassland prairie. If we add the factor that the grassland prairie must be burned annually to maintain it, clearly the grassland prairie is an ecological deficit because it releases pollutants and greenhouse gases into the atmosphere when it is burned.

The moving target

The goals of ecological restoration are a moving target. The original goals of re-creating an historical landscape that would be sustainable without continual maintenance are now widely acknowledged to be unrealistic.

The new goals are equally elusive. The new goals are described in obscure ways that will be impossible to measure or evaluate. That suits the purposes of native plant advocates perfectly. They can continue to do whatever they want and the public can’t hold them accountable because the public is not provided with a practical method of measuring success or failure.

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(1) Stuart K. Allison, Ecological Restoration and Environmental Change: Renewing Damaged Ecosystems, Routledge, UK, USA, Canada, 2012

“Hey, You Calling Me an Invasive Species?”

The New York Times published an op-ed by a member of their Editorial Board on Sunday, September 8, 2013, entitled, “Hey, You Calling Me an Invasive Species?” It is a spirited defense of non-native plants. Surely this is an indication that our challenge of the native plant movement is now mainstream. We will touch on a few of the op-ed’s main themes, but we urge you to read the op-ed here.

Mount Sutro Forest is threatened with destruction because it is not native. Courtesy Save Sutro Forest.

Using the eucalyptus forest on Mount Sutro as an example. the Editorial Board member, Verlyn Klinkenborg, makes the point that many of our non-native plants have been here for hundreds of years. Since they have been here for several generations of humans, most of us no longer consider them foreigners:

“But the trees on Mount Sutro have been there within the memory of every living San Franciscan, and to the generations who have grown up within view of them, it seems almost perverse to insist that they are alien.”

The distinction between native and non-native depends upon an arbitrarily selected “snapshot” of our landscape taken just prior to the arrival of Europeans. On the East Coast, that’s the early 16^th Century. In the San Francisco Bay Area, that’s 1769, when Portola’s men saw the San Francisco Bay. The Times op-ed reminds us that this particular snapshot is becoming more and more irrelevant because of climate change. If plants and animals don’t move in response to that change they will not survive:

“As plants and their pests adjust their range under the influence of global warming, what becomes of the distinction between native and nonnative? To any individual species, it doesn’t matter whether it’s native or not. The only thing that matters is whether its habitat is suitable.”

Finally, Mr. Klinkenborg takes us on a verbal tour of Central Park to make the point that our open spaces are a mélange of native and non-native plants and animals. We can see with our eyes that they are living in harmony and to pluck only those considered non-native from their midst would be needlessly destructive and disruptive of the peace that reigns there:

“Nature in Central Park can’t be divided into native or nonnative species, and neither can it be on Mount Sutro. The eucalyptus trees that grow there may be naturalized rather than native, but try telling that to all the other creatures that live in those woods or the people who hike there.”

Mr. Klinkenborg’s final sentence reminds us that we are the original “invaders:”

“And when it comes to the distinction between native and nonnative, we always leave one species out: call us what you will—native, naturalized, alien or invasive.”

The absurdity of nativism is becoming more and more evident. Our objections to its destructive consequences will eventually be heard. It’s just a matter of time.

No evidence that birds are harmed by non-native plants

The garden columnist of the San Francisco Chronicle wrote an article about the harmful effects of non-native plants on birds in 2012. She quoted an ornithologist as making these gloomy predictions about the harm that non-native plants may be doing to birds:

“Nonnative berries may not provide the nutrition that particular native birds require.”
“Nonnative fruiting plants could bring birds into a wildland habitat new to them, not necessarily with a good outcome. Birds might flock to a new area, feast on the new food source till it’s gone, but then not find enough food for so many birds in the rest of the habitat.”
“Nonnative plants alter wildland communities ‘in more complex ways than simply providing food for birds.’ A bird-dispersed nonnative fruiting shrub, for example, ‘can form underbrush or thickets in areas that previously lacked an understory…Birds may find their nesting sites disrupted, more cover for predators, etc.’”

Our initial reaction to these dire predictions was that they were entirely speculative. The consistent use of the word “may” to describe the consequences of non-native plants suggested that supporting evidence was absent. It seemed that, as usual, the nativist ideology was casting a dark pall on nature.

We were reminded of one of our first encounters with a nativist over 10 years ago. On a tour of a park in San Francisco, he claimed that non-native plants in San Francisco were creating a “sink” which he defined as attracting migratory birds into a climate to which they were not adapted, where they would eventually freeze to death. I pointed out to him that it does not freeze in San Francisco. He was unaware of this fact.

Secondly, we reacted to the implication of the Chronicle article that birds are passive in nature and incapable of making good choices for themselves. The suggestion is that birds are unable to discern nutritious food from “junk” food and incapable of choosing a safe nesting site to raise their young.

Thirdly, since every plant is native somewhere, we found the suggestion that non-native plants are nutritionally inferior to native plants illogical. Are we to believe that where these plants are native, birds are malnourished?

Where is the evidence?

And so, we decided to see if we could find any actual evidence that supports these statements. We started by looking at the research work of the ornithologist quoted by the Chronicle gardening columnist, Clare Aslan. She earned her Ph.D. in Ecology at UC Davis in 2010. Her Ph.D. project is described in a publication the year her degree was awarded: “Avian use of introduced plants: Ornithologist records illuminate interspecific associations and research needs.” (1)

In this publication, Ms. Aslan tells us that her project was essentially a questionnaire that was sent to over 1,000 non-professional bird watchers in four American states (California, Florida, New York, and Washington). These bird watchers were presumed to be skilled because they were members of Ornithological Societies of North America. Responses were received from 173 of these bird watchers, of which 51% were from California. Respondents reported 1,143 interactions between birds and plants. “Interact” is defined as the full range of bird behavior: eat, nest, perch, glean, etc.

The objectives of the questionnaire were: (1) to evaluate patterns of bird use of non-native plants to determine the role the birds play in dispersal of “invasive” plants; (2) to examine the food web and guilds formed by bird interactions; and (3) to determine gaps in empirical research to inform future research efforts.

Robin and chicks. Courtesy SF Forest Alliance

Respondents to the survey reported that 47% of observations of feeding by 139 bird species were of seeds or fruits of non-native plants. Thirty-five percent of all “habitat interactions” were with non-native plants and 26% of all nesting activity was in non-native plants. If non-native plants are harming the birds, nearly half of them must be in danger of starving to death!

Ms. Aslan tells us nothing about the relative nutritional value of non-native plants compared to native plants in this publication. In her concluding paragraph, she suggests that her primary finding is that more research is needed to understand the role that birds play in the dispersal of “invasive” plants which has “direct application for invasion prevention.”

Perhaps Ms. Aslan was misquoted by the Chronicle garden columnist. If not, Ms. Aslan does not seem to have any empirical evidence to support her statements about the negative impact of non-native plants on birds.

Research about birds’ food preferences

Million Trees is always looking for the happy ending. Consequently, our next step was to search the scientific literature for evidence that birds are being harmed by non-native plants. It was not difficult to find several reassuring articles about the food preferences of birds:

One study found that birds do, indeed, have food preferences and their preferences are based on many factors, including color, size, and availability. However, “In addition to these factors the nutritional composition of fruit pulp also influences selection of fruits by birds.” (2)
Another study found that what birds choose to eat depends somewhat on their migratory patterns. They choose foods with more fat content immediately prior to a long migratory journey over “major ecological barriers” such as seas and deserts. (3)
In a native eastern forest in the United States, most of the nutritionally best fruit was eaten early in the season, prior to the beginning of the migration. Over-wintering birds were then left to eat the fruit that remained. (4)
Finally, a study of fruit in the tropics showed that fruit that is more conspicuously colored and/or displayed seemed to be compensating for lower nutritional value than less conspicuous fruit. The authors speculate that these are the evolutionary trade-offs that enable plant species to survive. (5)

All of these studies suggest that the birds know what they are eating and why. We find no reason to fret on behalf of the birds that are eating non-native seeds and berries. In fact, the eradication of some of the best food sources—such as Himalayan blackberries—may be a greater cause for concern. And, once again, we find the extreme negativity of nativism to be a bigger problem, with respect to the damage being done to the environment in the guise of saving the planet from the harm they have imagined.

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(1) Clare Aslan and Marcel Rejmanek, “Avian use of introduced plants: Ornithologist records illuminate interspecific associations and research needs,” Ecological Applications, 20(4), 2010.

(2) E.W. Stiles, “The influence of pulp-lipids on fruit preference for birds,” Vegetatio, Volume 107-108, Issue 1, 1993

(3) F. Bairlein, “Nutrition and Fruit Selection in Migratory Birds,” Bird Migration, Springer Berlin Heidelberg, 1990

(4) John W. Baird, “The Selection and Use of Fruit by Birds in an Eastern Forest,” The Wilson Bulletin, Vol 92, No 1, March 1980

(5) Nataniel Wheelwright and Charles Janson, “Colors of Fruit Displays of Bird-Dispersed Plants in Two Tropical Forests,” The American Naturalist, Vol. 126, No 6, December 1985

Niche Theory: Is there room for everyone?

One of the basic tenets of invasion biology is “ecological niche theory.” According to that theory, every species occupies a specific niche to which it is adapted. That niche provides all the biological resources the species needs for its survival and reproduction.

A corollary to that theory is that when non-native species are introduced to that “niche” the native occupant is the loser in the inevitable competition for available resources. The intruder has the advantage in this competition because its predators have not usually been introduced at the same time. This is the “predator release” corollary.

Bmblebee on Cotoneaster, Albany Bulb — Bumblebee on Cotoneaster, Albany Bulb

Adherents to ecological niche theory therefore routinely predict the demise of native species whenever non-native species are introduced. Often, their belief in this inevitable competition leads them to see what they expect to see. The prediction that the introduction of the European honeybee to the New World would eventually decimate populations of native bees is an example of this mindset. Since honeybees were introduced to the New World over 400 years ago, it seems reasonable to expect to see some evidence of this consequence by now.

Seeing what we expect to see

Forgotten Pollinators was published in 1996, at the height of popularity of invasion biology. (1) We consider it a valuable, interesting book, but we were not impressed with the chapter devoted to the belief of the authors that the European honeybee is competing with native pollinators, to the detriment of native pollinators. Although the authors interviewed several other scientists who shared that belief, they were unable to offer any empirical evidence that supported their belief.

One of the studies cited in Forgotten Pollinators quantified the amount of nectar and pollen consumed by honeybees and compared that to the quantity of nectar and pollen required by native bumblebees. Based on those calculations, they predicted the demise of bumblebees based entirely on the amount of nectar and pollen consumed by honeybees. The study arrived at the preposterous conclusion that a single honeybee hive could reduce the population of bumblebees by 38,400.

This dire prediction is based on the assumption that there is a finite amount of pollen and nectar available. Therefore, every scrap of food collected by a honeybee is a scrap of food taken from a bumblebee. It also assumes that the bumblebee loses the competition 100% of the time and neither insect is capable of expanding its range in the unlikely event that there is in fact a finite amount of food available. This type of “zero-sum” thinking pervades the nativist ideology, e.g., a job taken by an immigrant is presumed to be taken from a resident.

Looking for bad news…finding good news

The federal government has invested in many careers and large sums of money to prove the assumptions of invasion biology as well as funding eradication projects based on those assumptions. For example, the University of Alaska, Fairbanks was awarded a federal grant for $493,000 to test the hypothesis that the existence of non-native sweetclover is drawing pollinators away from wild native food sources such as cranberry and blueberry bushes. After several years, researchers have concluded, “…there’s usually room for everybody.” (2)

The researchers monitored 20 sites for two years. They observed that the sweetclover patches “were actually attracting three times as many pollinators to native plants as they would otherwise get.” The sweetclover attracted many different types of pollinators, including moths, flies, and wasps. Consequently there were many more cranberries in the “invaded” patches and equal quantities of blueberries.

Suspicious of those findings, the researchers moved their project to a controlled setting. Then they got mixed results, which seemed to depend upon variations in the weather.

Researchers are still intent to find negative consequences of the existence of sweetclover. Now they are hoping to prove that the sweetclover is changing the composition of the soil, which they predict will eventually “crowd out” the native plant species. Will they keep looking until they can report bad news?

Empirical evidence is absent

After reading this good news about the exoneration of sweetclover in the nativist blame game, we decided to revisit the accusations made by Forgotten Pollinators about honeybees causing the decline of native bee populations. Our search of scientific literature published after the publication of Forgotten Pollinators in 1996, was very revealing and is best represented by a review article published in 2004, “Impact of the introduced honeybee on native bees: A review.” (3)

The review analyzes 28 studies conducted all over the world about the impact of honeybees on populations of native bees. This is a summary of the analysis:

“Although previous studies investigating indirect measurements have been cited as evidence of competition between honey bees and native bees, many of these studies were compromised by low replication, confounding factors or poor interpretation. Studies that are well designed and implemented may find the potential to impact negatively on native bees but the use of indirect measurements does not reveal [their impact on] long-term survival of native bees.

More direct studies of the impact of honey bees on native bee survival, fecundity or population density have shown little evidence that the presence of honey bees has any impact on native bees.” (3)

As we often do on Million Trees, we conclude with this rhetorical question: How does invasion biology survive in the absence of empirical evidence that supports its hypothetical assumptions?

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(1) Stephen Buchmann & Gary Paul Nabhan, Forgotten Pollinators, Island Press, 1996

(2) “Invasives pollination study shows mixed results for Alaska berries,” Fairbanks Daily News-Miner, August 23, 2013

(3) D.R. Paini, “Impact of introduced honey bee (Apis mellifera) on native bees: A review,” Austral Biology, (2004) 29, 399-407.

Another example of increased biodiversity on an “invaded” island

Nearly a year ago, we told our readers about a study of 371 publications testing the hypothetical assumptions of invasion biology, aptly entitled “Support for major hypotheses in invasion biology is uneven and declining.” The hypothesis least studied was “island susceptibility” which predicts that invasive species are more likely to become established and have major ecological impacts on islands than on continents. This hypothesis has considerable intuitive appeal because species that evolve in isolation are more likely to diverge from their ancestors in response to specific conditions which predicts a large number of endemic species unique to that island. In fact, the results of 9 studies of the island susceptibility hypothesis found that only 11% of those studies supported the hypothesis.

Subsequently, we were able to tell our readers about two specific examples of studies of islands where introduced species significantly increased biodiversity and benefited native species. In Puerto Rico, Ariel Lugo found that non-native trees were restoring depleted agricultural soils and providing shelter to native trees. In Hawaii, Joe Mascaro found that non-native trees were performing the same ecological functions as native trees and that non-native trees capable of nitrogen-fixing were creating soil on barren lava flows, greatly accelerating revegetation.

Ascension Island

Ascension is another example of an island on which biodiversity has been increased significantly by the introduction of non-native species. Ascension is in the Atlantic Ocean, roughly midway between South America and Africa. It has therefore been crucial for hundreds of years to travelers to resupply their long voyages. The British claimed it as a naval base in 1812. It was vital during World War II as a base for both American and British warships and submarines. It now has a huge air strip used by American and British military.

Ascension emerged from the ocean as a volcano about a million years ago. The volcano was active until about 700 years ago. There was therefore little vegetation on the island when it was first occupied by the British 200 years ago. They introduced domestic animals as well as agricultural crops needed to supply their ships making the voyage across the Atlantic Ocean. Many unintended hitchhikers also made the voyage to Ascension, such as cats and rats.

“Naked Hideousness”

Green Mountain, Ascension. Creative Commons

By the time of the visit of Charles Darwin to Ascension in 1836, little of the sparse natural vegetation remained. Darwin complained of the “naked hideousness” of the island. Returning to England, Darwin convinced his friend and fellow botanist Sir Joseph Hooker that Ascension would benefit from the introduction of plants and trees: “The idea was that the new vegetation on the mountaintop would scavenge moisture from the passing clouds. Further down the slopes, planting would encourage soil growth” on the barren lava. (1)

Drawing from the collection of Kew Gardens in London, Joseph Hooker shipped trees from all over the world to Ascension: “By the late 1870s Norfolk pines, eucalyptus, bamboo, and banana trees grew in profusion at the highest point of the island, Green Mountain, creating a tropical cloud forest.” (2)

Ascension Today

Yale Environment 360 recently published the report of a visitor to the man-made tropical forest on Ascension, Fred Pearce. (1) He is a British freelance writer. His guide on Ascension was the island’s conservation development officer, Stedson Stroud. Stroud told him that except for a few native ferns, everything on the island today has been introduced. He acknowledged that as a conservationist he might be expected to be engaged in an effort to eradicate all the non-native species. “But if he did, there would be almost nothing left. And in any case, he mused, he is presiding over something profoundly interesting—a functioning ecosystem to which a ragbag of species shipped in from all over the world thrive as if they had been together for millennia.” (1)

There are 300 introduced plant species on Ascension, adding to the 25 native plant species of which 10 are endemic (unique to Ascension). Three native plant species are said to be extinct. However, “…many of the endemics seem to get on remarkably well with the motley collection of invaders, says Stroud. The ferns that once clung to the bare mountainside now prosper on the branches of introduced trees like bamboo. Stroud showed [Pearce] ferns that he believes now thrive only on the mosses that grow on such branches…And Stroud says the vegetation captures more cloud moisture just as Hooker had hoped, even though rainfall has declined in the lowlands around.” (1)

The message that some scientists don’t want to hear

The conservation officer interviewed by Pearce expressed his frustration that scientists visiting Ascension are not interested in the thriving ecosystem on Green Mountain. Conservation research is still hung up on native ecosystems because the “…standard theory [is that] complexity emerges only through co-evolution…According to mainstream ecological theory, this cloud forest really should not exist. Certainly it should not thrive. Complex forest ecosystems are believed to take millions of years to develop…” But the fact is, the cloud forest on Green Mountain “strongly suggests that even highly biodiverse ecosystems may often be accidental, temporary, and versatile.” (1)

Pearce concludes that there are practical implications for conservationists who are trying to reassemble the complex ecosystems that have been lost. We might have better results from simply letting nature take its course. Most visitors to our cloud forest in San Francisco, Mount Sutro, would probably agree with that strategy. How could destroying 90% of the forest and its understory on 75% of the acres be an improvement over what we have now?

Update: Professors Daniel Simberloff and Donald Strong have posted a “counterpoint” to Fred Pearce’s article about Ascension Island. It is available here.

Professor Simberloff is one of the most notable academic proponents of invasion biology. Professor Strong is the creator of the project to eradicate all non-native Spartina marsh grass from the entire West Coast of the US.

Their counterpoint looks like rhetorical flailing to us. Although littered with detail, its argument seems convoluted and ultimately leaves one wondering if they are making any point other than their deep desire to defend their academic turf.

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(1) Fred Pearce, “On a Remote Island, Lessons in How Ecosystems Function,” Yale Environment 360, August 26, 2013

(2) http://en.wikipedia.org/wiki/Ascension

East Bay Regional Park District fuels management projects

Sibley "fuels management" 2012 — Sibley “fuels management” 2012

On Thursday, August 29, 2013, the Executive Committee of the Board of Directors of the East Bay Regional Park District will consider the District’s plans for fuels management in 2014. In April 2010, the District’s Board of Directors approved the “Wildfire Hazard Reduction and Resource Management Plan” and its Environmental Impact Report. That plan provided for an annual progress report as well as budget and project planning for each forthcoming year.

Here is the District’s report of what has been accomplished so far and the projects planned for completion by the end of 2013:

“In 2012, initial entry work was undertaken at Anthony Chabot and Sibley, for a total of 153 acres, including 140 acres of eucalyptus thinning in and around the Anthony Chabot Family Campground and 13 acres of eucalyptus thinning in the steep slopes of Sibley Triangle. Approximately 1,500 tons of hazardous wildland fuels were treated.

The District’s resource management prescribed broadcast burn program is continuing in 2013. Approximately 50 acres of native prairie grassland in Point Pinole and 80 acres of invasive plants in Round Valley are scheduled for burning this year.

By the end of 2013, a total of 160 acres of initial entry work are expected to be completed at Anthony Chabot, Claremont Canyon, Kennedy Grove, Lake Chabot, Sibley, Tilden, and Wildcat Canyon. Approximately 900 acres across 16 parks will be maintained using goat grazing, prescribed burns, and chemical, mechanical, and hand labor as described in the 2012 report, and in accordance with the prescriptions and treatment protocols adopted in the Plan.” (1)

We would like to be able to tell our readers about the pesticides required to accomplish these tasks. Unfortunately, the District has not posted an annual report of its pesticide use since 2010. The District says it does not expect to complete the annual report of pesticide use for 2011 until late in 2014. Meanwhile, you can see the latest report for 2010 that is available here.

Here are the District’s plans for implementation of fuels management projects in 2014 (Attachment B of report available here):

Project Description	Estimated Cost	Estimated Acres
Annual maintenance of light, flashy fuels and eucalyptus sprouts in Fuels Plan area	$500,000	671
Annual maintenance of light, flashy fuels OUTSIDE of Fuels Plan area	$175,000	268
Periodic maintenance of heavy fuels (brush and ladder fuels) in Fuels Plan area	$250,000	70
Sub-Total Fuels Maintenance	$925,000	1009
Initial treatment of heavy fuels and eucalyptus in Fuels Plan area (Chabot, Claremont Canyon, Huckleberry, Leona, Redwood, Sibley, Sobrante Ridge, Tilden, Wildcat)	$1,200,000	544
Initial treatment OUTSIDE Fuels Plan area	$50,000	15
Sub-Total Initial Treatment	$1,250,000	559
Resource/habitat prescribed burns	$25,000	126

TOTAL FUELS MANAGEMENT	$2,200,000	1694

You can see exactly what will be done and where by looking at Attachment C of the report (available here). All the “recommended treatment areas” are listed where the work is planned. There are maps of the “recommended treatment areas” in the “Wildfire Hazard Reduction and Resource Management Plan” which is available here.

The District expects to complete initial treatment on all 3,000+ acres of the fuels management project in 2019. The District estimates that the annual cost of maintaining those treated acres will be between $2,055,000 and $5,400,000 per year in perpetuity. If you read our recent post about the Marin County Parks and Open Space “Vegetation and Biodiversity Management Plan” you know that all managers of public land in the Bay Area report the mounting costs of maintaining the fuel breaks they have created because when vegetation is cleared, the ground is quickly occupied by non-native weeds. Our readers will recall that the author of that report recommends that fuels management projects be sharply curtailed so as to reduce the maintenance problems that are created by them. The report also states that fire hazards will not be increased by curtailing vegetation management projects as recommended. The projected costs of maintaining fuel breaks in the East Bay Regional Park District are an example of the maintenance nightmare that is being created by these projects.

The meeting of the Board Executive Committee will take place at 12:45 pm on Thursday, August 29, 2013, at District headquarters: 2950 Peralta Court, Oakland, California. The public has an opportunity to comment at these meetings. You could, for example, ask why the District’s annual report of pesticide use hasn’t been made available to the public since 2010. Your tax money is being used to fund these projects. So, you have a right to know how your money is being spent.

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(1) Background Information for the August 29, 2013 Board Executive Committee Meeting, 2014 Fuels Management Program of Work and Fuels Cost Analysis.

“The Fanaticism of the Apocalypse”

The Fanaticism of the Apocalypse: Save the Earth, Punish Human Beings is a critique of modern environmentalism by a French philosopher, Pascal Bruckner. (1) I read it slowly and thoughtfully, savoring its eloquence that is a testament to the elegance of the French language. However, because it is so close to the center of my advocacy, I don’t have confidence that I can do it justice in a description for our readers. Therefore, I quote this brief review from the Amazon website:

“The planet is sick. Human beings are guilty of damaging it. We have to pay. Today, that is the orthodoxy throughout the Western world. Concern about the environment is legitimate, but catastrophism transforms us into cowering children. Distrust of progress and science, calls for individual and collective self-sacrifice to “save the planet” and cultivation of fear: behind the carbon commissars, a dangerous and counterproductive ecological catastrophism is gaining ground.

Bruckner locates the predecessors of today’s ecological catastrophism in Catholicism’s admonishment to give up joy in the present for the sake of eternal life and in Marxism’s demand that individuals forsake personal needs for the sake of a brighter future. Modern society’s susceptibility to this kind of catastrophism derives from what Bruckner calls the “seductions of disaster”, as exemplified by the popular appeal of disaster movies. But ecological catastrophism is harmful in that it draws attention away from other, more solvable problems and injustices in the world in order to focus on something that is portrayed as an Apocalypse. Rather than preaching catastrophe and pessimism, we need to develop a democratic and generous ecology that addresses specific problems in a practical way.

This sharp and contrarian essay on one of the great issues of our time will be widely read and discussed.”

Here are a few of the themes in this thought-provoking book that struck a chord with us:

Pervasive pessimism of extreme environmentalism

It was some comfort to know that we are not unique in our reaction to the extreme negativity of the branch of environmentalism that is driving the native plant movement in the San Francisco Bay Area. When we walk in the urban forest, which we often do, we enjoy the bird song, the rustle of the wind in the trees that surround us, the flicker of sunlight through the leaves, and the lush green of the understory in places like Mount Sutro. When native plant advocates describe the same places, we often wonder if they inhabit a dark, parallel universe. They see a degenerate, dying forest, being strangled by vegetation, inhabited solely by rats. Destruction is the only cure for the catastrophic disease they see.

We laboriously try to change their perception by providing them with what seem to us irrefutable facts: the opinions of scientists about the health of the forest, including a local professor of urban forestry, detailed censuses of the birds and animals that live in the forest conducted by reputable scientists, the scientific studies about changes in our urban ecosystem that are an inevitable consequence of the rapidly changing environment, the photographic evidence that non-native forests have not “invaded” our open spaces.

Pascal Bruckner explains why these facts fall on the deaf ears and blind eyes of native plant advocates. In an increasingly secular world, extreme environmentalism satisfies many of the same human needs that were satisfied by religious belief in the past. The appeal of religion starts with the deep guilt we often feel for the failings that are an inevitable part of life. Religion offers redemption from guilt, but first it asks us to pay a price in the form of penance for our sins.

Extreme environmentalism derives from our guilt for the damage humans have done to the Earth. Redemption requires that we heal that damage. In the case of native plant advocates, the damage to the Earth is symbolized by the demise of native plants. The restoration of native plants is the penance they believe we must pay to expiate our guilt.

We are unable to convince these true believers that these projects inflict more damage on the Earth in the fruitless attempts to restore native plants where they are no longer adapted, by destroying healthy trees and spraying our public lands with herbicides because their belief is based on faith and faith cannot be swayed by facts. No price is too great to pay for the restoration of native plants. Any damage inflicted in the process is incidental to their quest for redemption.

The seductive appeal of having an enemy

Bruckner also reminds us of the appeal of having a clearly defined enemy. For most of the 20^th century, the ideological enemy of the West was Communism. The Cold War satisfied the need for an enemy. The West was defined by anti-communism. We were united in our opposition to a common enemy. The ideological waters have been muddied by the demise of Communism.

Bruckner believes that extreme environmentalism has satisfied the need for an enemy for some people. Consumption and materialism are the enemies of extreme environmentalism. If you have engaged in the debate with native plant advocates in the past 15 years, you will know what we mean. We have been called “selfish nature haters” and “creepy imbeciles” in those debates. Comments on this blog have accused us of being funded by the Koch brothers, of sounding like Fox News, and of being as uncompromising as the NRA. We are mystified by the association with right-wing politics.

However, we take Bruckner’s observation to heart. We are a part of a large community of people who are opposed to the destruction associated with native plant “restoration” projects in the San Francisco Bay Area. We know that people come to that conclusion from a variety of perspectives. Some are primarily concerned about the destruction of healthy trees. For others, the use of herbicides is the primary issue. The impact on wildlife living in our open spaces is sometimes the chief concern.

Just as we are a diverse coalition of people, who come to this issue from a variety of perspectives, we must make every effort to treat native plant advocates as the individuals they surely are. We must listen to their opinions with an open mind, look for ways to compromise with them, and treat their concerns with respect. We will not be seduced into treating native plant advocates as enemies.

Looking for the light in Bruckner’s thesis

We share many of the concerns of extreme environmentalists about the future of the Earth. Although we agreed with Bruckner’s cautionary tale about the hopeless negativity of extreme environmentalism, we found little to reassure us about an alternate course. Bruckner merely reminds us that dark predictions about the fate of humans are not new. The end has been prophesied many times in human history. And the way forward was not predictable before it materialized in the form of the technological innovations that resolved each existential crisis. Our adaptability has been repeatedly demonstrated and we trust that it will be again, though we are unable to foresee it at the present time.

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(1) Pascal Bruckner, The Fanaticism of the Apocalypse: Save the Earth, Punish Human Beings, Polity Press, Cambridge, England, 2013

Comparing the Sutro Forest with Albany Hill

In a recent edition of Jake Sigg’s Nature News, one of his readers compared the Sutro forest unfavorably to the eucalyptus forest on Albany Hill:

“The [Sutro] ‘ forest ‘ is unmanaged, many of the trees are deteriorated and unhealthy, spacing is unusual and given the super invasive ivies and H. blackberry, overall habitat diversity is degraded.

For example , I look at El Cerrito Hill [officially Albany Hill] (near Central Av exit of east bay I-80 at Golden Gate Fields) and see a ‘ eucalyptus’ forest with fewer and larger trees , featuring an adjacent and penetrating coast live oak woodland and a ground cover that features wide species diversity.

Granted El Cerrito does not have the fog intensity of Mt. Sutro, BUT it also shows signs of management…

Anyway, all of this is my un-scientific observation. I think, with some thinning of eucs, control of ivy and blackberry spread, the establishment of habitat corridors and discreet regions and maintenance of trails, that Mt. Sutro could continue to provide a ‘ forest’ aesthetic and include much improved habitat diversity and fire potential reduction.”

We are always trying to understand the perceptions of native plant advocates in the Bay Area, so we went to take a look at Albany Hill. We are happy to report that we found much to like. However, the comparison with the Sutro forest is mistaken in many ways, which we will explain in this post.

Creekside Park

We started our walk at the Creekside Park on the north side of Albany Hill. It is a riparian corridor created by the confluence of two creeks, Cerritos and Middle creeks. The vegetation is almost exclusively native. The Creekside Park is carefully tended by native plant advocates who have planted many of the natives, but the Coast Live Oaks that are the predominant tree species are said to have been here prior to settlement. (1)

The oaks cover the northern slope of Albany Hill, which was typical of native oak woodland in the East Bay . The oaks benefit from the water provided by the creek and they also occupied north-facing slopes where there is more moisture in the soil than on the south facing slopes that are exposed to the sun. The prevailing wind in the Bay Area is usually from the southwest, so there is also some protection from the wind on the north side of the hill. There were never any oaks on Mount Sutro, and the assumption that there will be in the future seems delusional, given their horticultural requirements.

Looking up from the Creekside Park, we can see the eucalyptus forest on the top of Albany Hill which has not “invaded” the oak woodland. The fact that the eucalyptus forest has not encroached on the oak woodland is documented by two planning documents. The first “Albany Hill Master Plan” was written in 1991. It included vegetation maps that can be compared to the second “Albany Hill Creekside Master Plan” which was written in 2011. The second plan states that the eucalyptus forest had not expanded during that 20 year period. It also states that the eucalyptus forest isn’t regenerating. That is, it is not replacing itself, let alone expanding. Yet, it is consistently called an “invasive species” in the master plan approved in 2012. (2) “Invasive” seems to be the pejorative adjective used by native plant advocates to describe all non-native plants and trees, whether actually invasive or not.

During that 20-year period from 1991 to 2011, the eucalyptus forest was not “managed” as Sigg’s correspondent believes, because the plan was not funded. (1) Hence, a second plan was written in 2011. This is a scenario we often see played out on our public lands. Elaborate plans are written. Often they are not implemented. Sometimes we are just as happy they aren’t.

Let’s enjoy a few of the beautiful native plants and trees before we leave Creekside Park to visit the eucalyptus forest on the top of the hill.

This is a lovely little Madrone in full bloom. We recall wanting to plant a Madrone in our backyard over 30 years ago. They weren’t available in nurseries then. We assume they are now, which is great. But we digress.

This is one of the few California lilacs (ceanothus) we saw. Bumble bees were busy in the lilacs. They are nesting close by in the ground beneath an oak. If the bared ground on Mount Sutro is covered in the wood chips of the trees that are destroyed, as planned, native bees will not be able to penetrate that deep wood mulch.

This is one of many lovely oak trees, surrounded by ivy, which doesn’t seem to be doing it any harm. In fact, the master plan for Albany Hill says there are no plans to eradicate ivy in the riparian corridor because it “…would require considerable cost and labor to fully eradicate and whose spread is often limited to areas in the immediate vicinity.”

The Eucalyptus Forest on Albany Hill

The eucalyptus forest on Albany Hill was planted by a dynamite company in the late 19^th century. The trees were planted to muffle the sound from frequent explosions, as well as provide some protection to neighboring residents. (1) There were many reasons why early settlers to the Bay Area planted eucalypts. Some were practical reasons, such as this, and some were aesthetic.

Albany Hill is much drier than Mount Sutro. It is further away from the ocean where fogs form and often hover for weeks on end during the summer. In general, the East Bay is considerably less foggy than San Francisco.

Because it is a much drier environment, the eucalyptus forest on Albany Hill is less dense than the Sutro forest and it has considerably less understory. The understory on Albany Hill is non-native annual grass and native toyon shrubs, which are said to have been planted either by man or by birds “carrying” seeds from other locations. (2) Hmmm….let’s stop to think about that. The toyon is a native shrub that was “introduced” to Albany Hill and is thriving there under the canopy of the eucalyptus forest. The 2012 master plan for Albany Hill says that the toyon understory has expanded since the 1991 master plan.

The future of the eucalyptus forest on Albany Hill

As we have said, the eucalyptus forest on Albany Hill has not been “managed” to date. Since the master plan was approved in 2012, only $50,000 has been allocated for vegetation management on Albany Hill. So, what is planned for the eucalyptus forest in the future? Here are the plans for the future, according to the master plan that was approved in 2012:

The eucalyptus forest will be “phased out” slowly over time by removing hazardous trees as necessary to ensure public safety, removing new seedlings where the forest interfaces with native oak woodland, and not replacing trees that die of old age. Since the predominant species of eucalyptus in the Bay Area (Blue Gum) lives in Australia from 200-500 years, and it has been here for only about 100 years, it is reasonable to assume that this is a very long-term plan.
This plan should require a lot less herbicide than destroying 90% of the trees on 75% of Mt. Sutro, as planned there, because we assume a dead tree will not resprout. A lot of herbicide is often needed to prevent resprouts after healthy eucalypts are cut down.
The forest will be managed for fire safety by mowing the annual grasses, where ignition is most likely to occur; by limbing trees up to separate the understory shrubs from tree limbs to remove “fire ladders” to the tree canopy; and by cleaning woody debris from under the trees on an annual cycle.
The plan acknowledges the benefit of maintaining a closed canopy, both in the eucalyptus forest and the oak woodland. The closed canopy shades the forest floor and suppresses the growth of non-native weeds.

This all sounds eminently reasonable to us: much less destructive than plans for the Sutro forest, yet addressing fire hazard and safety issues in a responsible way.

Neighbors on the leeward side of the hill will eventually lose their windbreak as the tall trees disappear, but that will happen so slowly that they are unlikely to react. On the other hand, plans for Albany Hill could change many times in the next 100 years. We hope the current preoccupation with the nativity of plants and trees will have faded long before the eucalyptus forest dies of old age.

And so, ironically, we agree with Jake Sigg’s correspondent that plans to manage Albany Hill are better than the plans to destroy the Sutro forest. We just don’t agree about why.

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(1) http://en.wikipedia.org/wiki/Albany_Hill

(2) “Albany Hill Creekside Master Plan,” City of Albany, 2012

The Endangered Species Act is based on outdated science

We have reported to our readers many times about the changes in scientific opinion regarding invasion biology in the past fifty years, since the inception of the theories that originally supported that discipline. Now we see an acknowledgement of the changed scientific viewpoint in a critique of the Endangered Species Act by the legal profession.

Holly Doremus is Professor of Law at Boalt Law School at the University of California, Berkeley. Her critique of the Endangered Species Act (ESA) was published by the Journal of Law & Policy in 2010. She previews her theme in her introduction:

“I am interested in why the ESA came to assume an unrealistically static vision of nature. First, the Act’s static structure is typical of law in general, which has traditionally embodied the human search for stability. Second, the Act is inevitably, a product of the political times in which it was drafted and of a rapid and chaotic legislative process, which did not encourage thoughtful examination of the complex contours of the conservation problem. Third, it followed in part from incorrect but widely shared assumptions about the nature of the problem and potential solutions. Fourth, scientific understanding was itself in transition as the law was being crafted, moving from a focus on the tendency of ecological systems to approach equilibrium to one on the ongoing dynamics of many systems.” (1)

We will focus on the fourth issue, i.e., how the ESA is in conflict with the reality of constantly changing ecosystems.

A Static Vision of Nature

The ESA is based on assumptions about nature that were the conventional wisdom at the time the law was passed in 1973:

Evolution was considered a series of events that occurred in the distant past and is no longer actively changing plant and animal species. Theoretically evolution does not end, but at the time the ESA was passed in 1973, it was not believed to occur within a time frame that would be observable by man. Plant and animal species were therefore viewed as being distinct and unchanging.
This view of evolution was consistent with the prevailing public opinion in the United States, which does not believe in evolution. Many Americans believe that species have not changed since they were created by God.
Nature was perceived as reaching an “equilibrium state” that was stable over long periods of time.
Early conservation efforts were therefore based on the assumption that once achieved, an equilibrium state could be sustained if left undisturbed in nature preserves.
Darwin’s finches are an example of rapid evolution

We now know that these assumptions were mistaken. Evolution can occur very rapidly, particularly amongst plants and animals with short life spans and frequent generations. And ecosystems are constantly changing, particularly at a time of a rapidly changing climate and associated environmental conditions such as atmospheric conditions.

Professor Doremus tells us that ecological scientists played no role in the writing of the ESA and took little notice of the law when it was passed. The press also ignored the new law, which may have been a factor in its being unnoticed by the scientists who may have been in a position to raise the questions that should have been asked. “It seems that conservation scientists, like the general-interest press, and most legislators, did not consider the ESA groundbreaking, or even particularly important.” (1) In any case, the problems that have arisen in the implementation of the law were not foreseen by the politicians who passed it, nearly unanimously in 1973.

How does the ESA define “species?”

As its name implies, the heart of the law is how “species” are defined. In fact, if the law had stopped at providing legal protection for “species,” we would not be experiencing nearly as much difficulty with the implementation of the law. Unfortunately, the ESA’s “…definition of ‘species’ [is] broad, but not a model of clarity, ‘The term “species” includes any subspecies of fish or wildlife or plants, and any distinct population segment of any species of vertebrate fish or wildlife which interbreeds when mature.” (1)

Splitting species into sub-species and “distinct population segments” has proved problematic because taxonomy (the classification of organisms) has always been inherently subjective and will probably continue to be. The taxonomic system that was popular at the time the ESA was passed was Mayr’s biological species concept which identifies as a species any group that interbreeds within the group but not with outsiders. This definition is not useful for a species that hybridizes freely, such as the manzanitas of which six species have been designated as endangered. Professor Doremus tells us that US Fish & Wildlife Service now evaluates the legal consequences of hybridization on a case-by-case basis.

Since the ESA was passed, many competing definitions of “species” have been proposed by scientists. There were 22 different definitions of species in the modern literature as recently as ten years ago. These competing definitions reflect disagreement about appropriate criteria for identifying species—morphology, interbreeding, or genetic divergence, as well as the degree of difference needed to define the boundary between species. We see these scientific controversies played out repeatedly in the law suits that are interpreting the ESA.

The identification of “distinct population segments” amongst vertebrates has proved to be even more problematic. Legal challenges to the determination of distinct population segments have reversed the rulings of the US Fish & Wildlife Service for many species that were considered genetically identical such as the sage grouse (eastern vs, western?) and the Preble’s meadow jumping mouse (found in different meadows in the Rocky Mountains). In some cases, these rulings were reversed several times, and perhaps will be again! These reversals reflect the ambiguity of the law, as well as the science of taxonomy. The fact that the ESA specifically allows “citizen suits” has pushed the regulating agencies to implement the law more aggressively than politics alone would have predicted.

Species can and do move

In addition to considering species immutable and unchanging, the ESA also takes a static view of where they live. The concept of “distinct population segments” depends somewhat on the assumption that species of animals don’t radically alter their ranges in the short-term. The assumption is also consistent with the underlying conservation policies that tend to preserve specific places in order to protect rare species within those places.

We now understand that some ecosystems are internally dynamic. We recently told our readers of the need for the sand dunes near Antioch, California to move freely in the wind to sustain that fragile ecosystem. Professor Doremus also tells us about the constantly changing courses of braided rivers in Nebraska that are essential to the sustainability of that unique ecosystem.

Platte River in Nebraska is a braided river. Creative Commons

In a rapidly changing climate, the preservation of a species may require changing ranges. If the climate becomes too cold, too hot, too wet, or too dry for a species of plant or animal, its immediate survival may require that it move to higher or lower altitudes or latitudes. Moving may be a more effective strategy than the adaptation that may be slower than necessary to survive. Freezing species into their historic ranges does not ensure their survival at a time of rapidly changing climate. In some cases, a species has become plentiful in the new territory it has freely chosen to inhabit and simultaneously rare in its historic range where it has been designated as an endangered “distinct population.” Draconian measures have been taken to restore a species in its historic range, where it is no longer adapted to current conditions.

We leave you with Professor Doremus’ observation about the ESA: “The ESA’s static view of species, landscapes, and conservation obligations, while entirely understandable, has become a hindrance to effective conservation. The ESA’s lofty goals of conserving species and the ecosystems upon which they depend cannot be achieved without a more realistic vision of the dynamic qualities of nature and the ability to respond to the changes that are inevitable in dynamic systems.”

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(1) Holly Doremus, “The Endangered Species Act: Static Law Meets Dynamic World,” Journal of Law & Policy, Vol. 32: 175-235, 2010.