Catalina Island: Island ecology and restoration

Catalina Island is dear to my heart because of several childhood vacations there.  It was thrilling to return after 60 years and find it unchanged from my memories.  Avalon, the small town of about 3,500 people, is still a quaint collection of little wooden shacks, painted bright colors.  But as an adult, my recent visit to Catalina was broader and encompassed the entire island, which was unknown to me as a child.  That broader perspective on Catalina is my focus today. (1)

Avalon Harbor, Catalina Island. Creative Commons

Catalina is one of the Channel Islands off the coast of Southern California.  It rose from the ocean about 5 million years ago as the result of geologic processes lifting the ocean floor as tectonic plates collided.  Like other oceanic islands (as opposed to those that broke off from continents), it was composed of barren rock for thousands of years.  It took thousands of years to build soil needed to support plants.  Then it took thousands of years to establish plants from the seeds blown in the wind from the mainland, brought by birds in their stomachs or adhered to their feathers and feet, or brought by waves carrying plants in storms.  When plants gained a foothold, the island was able to support insects brought by wind and waves.

The process of populating Catalina with plants and animals accelerated with the arrival of American Indians about 10,000 years ago.  Foxes were probably brought to Catalina by the Indians and oaks probably arrived as acorns brought by the Indians.  Archaeological remains of Indian settlements indicate that there were as many as 2,500 Indians living on Catalina, using only the food and materials available on the island or the surrounding ocean.

Most of the plant and animal life on Catalina came from the mainland of California, only 22 miles away from the island.  When plants and animals evolve in isolation from their ancestors, their gene pools gradually drift apart and are eventually distinct species.  That’s why there are about 60 plant and animal species on Catalina that are endemic, meaning that they exist only on Catalina.  This process of diverging evolution from mainland ancestors to unique island species is typical of all island ecosystems.

Europeans arrive on Catalina

Catalina was visited by Spanish explorers for the first time in 1542 and again in 1602.  Although their visit was brief, it was fatal because they brought diseases to which Europeans were immune and the Indians were not.  Most of the Indians on the island were killed by those diseases, a scenario that played out all over the New World in the 16th and 17th centuries.

Europeans tried to establish communities on the island in the 19th century, but their economic ventures were not successful.  They brought sheep, cattle and goats.  But there wasn’t sufficient forage for their herds and supplementing their diets by growing hay wasn’t economically viable.  They tried mining, but found little of value.  They introduced animals for hunting, such as mule deer and pigs.

Towards the end of the 19th century, Europeans made their first attempt to turn the island into a tourist destination.  The first effort ended when the entire town of Avalon burned in a fire in 1915.  That fire set the stage for the final chapter in the development of the island.  William Wrigley Jr. was able to purchase the entire island in 1919 in the “fire sale” that resulted in a bargain price.

The Wrigley Era on Catalina

William Wrigley Jr. made his fortune manufacturing and selling chewing gum.  He had the means to indulge his passion for the island, which he envisioned as a recreational paradise.  He built a magnificent Art Deco casino in Avalon that opened in 1929 and turned the town of Avalon into a famous destination that attracted celebrities as well as one million visitors each year, arriving on the huge steamers Wrigley built to bring them to Catalina.

Bison on Catalina Island. Creative Commons

Many movies were made on Catalina and movie stars were frequent visitors to the island.  One of the movies brought bison to the island to feature in their western themed story.  The bison herd grew and eventually became another challenge to the survival of vegetation on the island.

The conservancy era on Catalina

When William Wrigley died, his heirs changed the direction of the island’s development.  The island could have continued to grow into a tourist destination, but in 1972 Wrigley’s heirs decided that nearly 90% of the island would be turned into a nature reserve.  The Catalina Island Conservancy was born.  Access and development on conservancy land is restricted.

Catalina Island Conservancy land.

The conservancy has made big investments in restoring the island’s ecosystems and protecting endemic plant and animal species.  Sheep and cattle were removed, which wasn’t difficult because those enterprises had largely failed.  Feral pigs and goats were much harder to round up and were killed by hired sharp shooters.  The extermination of the pigs and goats was as controversial on Catalina as it has been on other Channel Islands.  A decade later, “with the quality of the island habitat rebounding and increased ecotourism revenue being realized by island businesses, the bitterness surrounding the pig and goat eradication is subsiding.  Conservation, contrary to popular belief, is not one long group hug.  This stuff can be hard.”  (1) Indeed, “restorations” in the San Francisco Bay Area have caused one pitched battle after another for over 20 years.  They might have been less heated battles if all opinions had been treated with equal respect, as they seem to have been on Catalina Island.

The population of mule deer is being controlled with hunting licenses.  Most of the herd of 600 bison was given to an Indian reservation in South Dakota.  The remaining herd of 150 is being controlled by a contraception program.  Maintaining the small bison herd is considered a concession to their popularity with residents and tourists on the island.

Island fox. Catalina Island fox is a sub-species of the Island fox on other Channel Islands. USFWS

The Catalina Island Fox, an endemic species, was nearly wiped out by distemper virus introduced by a castaway raccoon.  Fortunately, conservancy staff figured out why the population dwindled to only 100 foxes in time to save the foxes from extinction.  A captive breeding and vaccination program returned the fox population to over 1,500 animals in 2011.  A captive breeding program for the island’s bald eagles has also restored their population.

Invasive species

Like most restorations, the Catalina Island Conservancy is concerned about invasive species.  However, their approach to controlling non-native plants is less extreme than many similar projects.  They consider a species of broom (Genista linifolia) their highest priority for eradication.  Although they have tried and will continue trying to control it they acknowledge that it may not be possible.

Genista linifolia is native to the Canary Islands.  It was introduced to Catalina over 100 years ago when it was used to landscape the Saint Catherine Hotel when it was originally built in 1900.  The conservancy launched the Avalon Grasses Initiative in 2016 to prevent similar introductions of grasses that have a high potential to spread on the wind—such as pampas and fountain grass–from gardens in Avalon to conservancy wildlands.  Conservancy staff quietly patrol the gardens in Avalon, looking for these exotic grasses.  When they find them they approach the property owner with their proposal to remove them and replace them with native plants.  The 20 property owners who have agreed to this proposal express satisfaction with the substitution.  This strategy seems to treat the property owners with respect. (2)

Over 200 species of non-native plants live on the island, but the conservancy considers only 35 of the species a problem.  They describe their approach to non-native plants:

“The Catalina Island Conservancy has developed a thoughtful and comprehensive set of strategies for dealing with invasive plants.  First, they realized that not all introduced plants are invasive and some are less likely to outcompete native species.  Those considered invasive were ranked according to the magnitude of the problems they present, including how widespread they are, how fast they can spread and how damaging to the local native species they are.  On the basis of this information, each highly ranked invasive species is being treated with the purpose of reducing its impact on the native communities, reducing its spread or eliminating the threat.” (1)

They acknowledge that “topical chemical treatments” are one of the methods they use to control plants they consider invasive, but details of their pesticide use are not available to me.  The conservancy is a private entity that is not subject to public record laws.

My eucalyptus litmus test

Catalina Ironwood is one of few species of native trees on the Island. It is an endemic species, like most of the native trees on the island.

There are few species of native trees on Catalina Island and their population on the island is also very small.  Therefore, most trees on the island were introduced.  Eucalyptus (mostly Red River gum and blue gum) were introduced to the island in the 1920s by the Wrigley family for a variety of reasons:  aesthetic, shade, wind break, erosion control of road cuts, etc.  Eucalypts are still there and they are the predominant tree species on the island.  Eucalyptus is found throughout the island, including the town of Avalon and several places on conservancy land, where they were planted.

 

The bark of Catalina ironwood is shredded, similar to the peeling bark of Blue Gum eucalyptus

The conservancy does not plan to eradicate eucalyptus on the island:  “The eucalyptus trees…are non-native, but are not highly invasive. Because of their non-invasive growth pattern and their place in the cultural heritage of the Island, they are not targeted for replacement, except when they die of natural causes.” (3)

The myth that eucalypts are highly flammable that is used as an excuse to eradicate them in Northern California is not heard on Catalina Island.  An enormous wildfire torched about 10% of the island in 2007.  The fire started on conservancy land and spread to the outskirts of Avalon where it was finally extinguished after destroying several homes.  The town was evacuated and its residents stood on the beach front watching the fire approach their homes.  The eucalyptus trees that surround Avalon did not burn.  In the conservancy description of the fire, no mention is made of eucalyptus.  Although the fire was started by unsafe use of mechanized equipment, the conservancy describes fire as a natural and beneficial feature of the chaparral ecosystem of the island.

A street in Avalon is named “Eucalyptus Street.” In the background are some of the eucalypts that surround the town of Avalon.

A restoration that makes sense

I have been studying native plant restorations for over 20 years.  I have finally found on Catalina a restoration that makes some sense to me.  The restoration on Catalina Island has been more constructive than it is destructive.  It has killed less and preserved more.  It preserves eucalyptus because they aren’t doing any harm.  It does not fabricate a cover story to justify killing eucalypts just because they aren’t native. 

The conservancy also acknowledges that difficult choices must be made and that differing opinions must be respected.  Recreational interests and aesthetic preferences are not always consistent with the goals of conservation.  The conservancy preserves bison because people like to see them, despite the fact that they are not native to the island. Competing interests must be balanced if the restoration is to be supported by residents of the island:  “We have realized that people are an intrinsic part of the nature of the island—an influential and fundamental component of the conservation effort.”  (1)


Most of this article comes from this book (1) which was written by the leadership of the Catalina Island Conservancy:

  1. Frank Hein & Carlos de la Rosa, Wild Catalina Island: Natural Secrets and Ecological Triumphs, Natural History Press, 2013
  2. “Protecting Catalina’s Wildlands from Invasive Plants,” Catalina Island Conservancy Times, Fall 2017
  3. Catalina Island Conservancy website: https://www.catalinaconservancy.org/

Nativist fantasies about oaks

San Francisco Bay Estuary Institute is promoting a “restoration” project they call “Re-Oaking California.”  The project is planning to plant oak trees in California cities, in particular.  They have published an elaborate brochure describing their project and they have published a brief description in the quarterly newsletter of California Releaf, the biggest non-profit advocacy organization for California’s urban forest.  Locally, they have made a presentation to Oakland’s Urban Forestry Forum and to the Bay Area Open Space Council.  The Open Space Council convenes meetings of hundreds of public land managers from all over the Bay Area.  In other words, the re-oaking project is being aggressively sold to those who determine the future of our public lands.  Therefore, it is a project that deserves our attention.

First, I must say that I love oaks.  I decided to buy the home I now live in before I stepped inside, because of the beautiful coast live oak in the front yard.  The loss of that tree would be devastating both emotionally and to the value of my home.

However, my opinion of the re-oaking project is based on the reality of climate change and its implications for the future of California’s urban forest.  Although the project brochure acknowledges that Sudden Oak Death has killed many oaks in California, it does not accurately reflect the scale of that epidemic.

Sudden Oak Death

Sudden Oak Death (SOD) killed 5 million oak trees in California from 1994 to 2015, when that number was reported by a study. (1)  The study also said that the SOD epidemic could not be stopped and would eventually kill all oaks in California.  More recent estimates are that 5 to 10 million oaks have been killed by SOD. (2)

Tan oaks killed by SOD. US Forest Service

SOD is caused by a pathogen that is spread by rain and wind.  We had a great deal of rain in 2016 and 2017, which greatly increased the spread of SOD infections.  In the past, SOD has been mostly confined to wildlands.  Now it is found in many urban areas, including San Francisco and the East Bay.  In the most recent SOD survey done in spring 2017, new infections were found on the UC Berkeley campus, the UC arboretum, and the San Francisco Presidio. (2)

The scientist at UC Berkeley who conducts the annual survey of SOD infections reports that “A dramatic increase this year in the number of oaks, manzanita and native plants infected by the tree-killing disease known as sudden oak death likely helped spread the massive fires that raged through the North Bay…” (3)

Brice McPherson, Associate Specialist in Organisms and the Environment at UC Berkeley, has been studying SOD infections in Marin County and the East Bay.  He made a presentation in November 2017 about the current status of SOD infections in East Bay parks.  Wildcat Canyon is the park in which Mr. McPherson has most recently inventoried infected and dead trees.  In 2017, Mr. McPherson found that 16.2% of coast live oaks were infected and 20.5% were dead.  The number of dead and dying oaks in Wildcat Canyon is staggering:  18,750 oaks are infected and 21,360 oaks are dead.  McPherson predicted that 50% of all oaks in East Bay parks would be dead within 20 years, depending upon the amount of rainfall.

Native bay trees are considered the main vectors of the pathogen that causes SOD.  The re-oaking project therefore suggests that SOD infections in urban areas can be avoided if bay trees aren’t planted in proximity to the oaks.  However, the source of the SOD infection recently found in the Presidio in San Francisco is said to have been rhododendrons, which should remind us that bays are not the only vectors of the SOD pathogen.  In fact, the USDA reports 46 confirmed hosts for the SOD pathogen, including both native and non-native shrubs and trees. (4)  Many of the hosts are commonly found in urban gardens.

Climate change kills oaks in Southern California

Sudden Oak Death infections have not been found south of San Luis Obispo.  However, that does not mean that oaks in Southern California are any less threatened by changes in the environment.  Several land managers in Southern California made presentations at the recent conference of the California Native Plant Society in Los Angeles about massive die-offs of oaks in Southern California.  Here is an example from the Santa Monica Mountains:  “Over 9,000 coast live oak and 114,000 riparian trees died from [2014 to 2017]…” (5) These deaths were caused by extremely high temperatures to which the trees are not adapted, associated drought and new insect predators, such as shot-hole borer.

The unsuitable climate conditions in Southern California are the anticipated climate conditions of Northern California.  Carbon storage in our urban forest is one of the few tools we have to combat climate change.  Although coast live oaks store carbon, they are not particularly long lived.  Their life expectancy is from 125 to 250 years in suitable conditions. (6) Planting trees with no long-term future is not a responsible response to climate change.  The US Forest Service predicts coast live oaks will be virtually gone in California by 2060:

Wildlife in our urban forest

Although oaks are clearly useful to wildlife, they are not significantly more useful than other urban trees.  Here are three studies conducted in the East Bay that compare the biodiversity of animal life in oak woodland to other tree species:

Dov Sax (Brown University) studied six forest plots of about 1 hectare each in Berkeley, CA, three of eucalypts and three of native oaks and bays.  The sites were not contiguous, but were selected so they were of similar elevation, slope, slope orientation, and type of adjacent vegetation.  He conducted inventories of species in spring and autumn.  He counted the number of species of plants in the understory, species of invertebrates (insects) in samples of equal size and depth of the leaf litter, species of amphibians, species of birds, species of rodents.  This is what he found:

“Species richness was nearly identical for understory plants, leaf-litter invertebrates, amphibians and birds; only rodents had significantly fewer species in eucalypt sites.  Species diversity patterns…were qualitatively identical to those for species richness, except for leaf-litter invertebrates, which were significantly more diverse in eucalypt sites during the spring.”  (7)

In 1975, Professor Robert Stebbins (UC Berkeley) was hired by East Bay Regional Park District to conduct a survey of vertebrate animals living in several parks (Sibley, Chabot, and Tilden). The forest types that Professor Stebbins studied were redwood, Monterey pine, eucalyptus, and oak-bay woodland as well as grassland and dry chaparral. Here is how he described his findings:

  • “Redwood and Monterey pine habitats are notably depauperate in vertebrate species.
  • “Eucalyptus habitat is far richer in vertebrates than either redwood or Monterey pine and vies with ‘dry’ chaparral and grassland in species diversity and ‘attractiveness.’
  • “Oak-bay woodland is the richest in both species and ‘attractiveness.’
  • “Grassland is a little less rich in species and ‘attractiveness’ than the other native habitats, but only slightly richer than eucalyptus habitat.” (8)

A wildlife study of Angel  Island prior to the removal of most eucalyptus trees found:

“The total number of birds observed in native stands was similar to that observed in eucalyptus stands…Few small animals were caught in any stand; captures were in native stands five Norway Rats…in eucalyptus stands one Norway Rat…in grassland one Norway Rat and six California Voles…about three times as many salamanders were located in eucalyptus stands compared to native stands.” (9)

As David Ackerly said in response to a question at the recent conference of the California Native Plant Society, “There are few mutually exclusive relationships in nature.”  It is a risky evolutionary strategy.  If an animal is dependent upon a single plant species, it won’t survive in the absence of that plant species unless it is capable of adapting to available vegetation.  Despite the handful of examples given in the re-oaking brochure, wildlife in California is using non-native vegetation as often as native vegetation.

California’s urban forest is not native

The suggestion that California’s cities could be “refugia” for our threatened oaks is wishful thinking.  As Matt Ritter tells us in his book about California’s trees (A Californian’s Guide to the Trees Among Us), only 6% of California’s urban trees are native to California.  Thirty-three non-profit tree advocacy organizations in California (including California Releaf) told us why in their letter to California’s Natural Resource Agency about the Urban Greening grant program:  “Native trees are generally not suited to urban conditions.  They have difficulty adapting to the urban environment, thereby substantially reducing survivability…As an example, the approved list of street trees for the City of San Francisco includes no trees native to San Francisco.  In Oakland, two of the 48 allowed species are native.”

The future of California’s urban forest

So, what is the future of California’s urban forest?  Scientists with sufficient knowledge of trees are trying to answer that question and we would be wise to pay attention to their advice.  Greg McPherson gave a presentation in Davis on March 10, 2018 about “Growing Resilient Forests.”  McPherson’s research at the US Forest Service about the economic value of ecosystem services provided by urban trees (carbon storage, reduction of energy use for heat/cooling, increased property values, removal of particulate pollution, etc.) has been vital to those who defend our urban forest.

McPherson lives in Davis, where he is conducting a 20-year study about the urban forests of the future, i.e., those that will survive predicted changes in the climate. Three years into the study, his research team has made some preliminary recommendations for the trees that are likely to survive anticipated changes in the climateNone is native to Northern California. Most are foreign, particularly Australian.  (10)

Nativists deny reality of climate change

When the climate changes, the vegetation changes, moves, or dies.  That has been one of the few axioms in nature since life has existed on Earth and we would be wise to assume that it will continue to be true.  The future of California’s urban forest depends on our willingness to plant trees that are adapted to the climate and to the anticipated climate.  Climate change is killing California’s trees and nativism is preventing us from replacing them with suitable trees.


  1. https://www.sciencedaily.com/releases/2016/05/160502161111.htm
  2. “Disease killing oaks spreads,” East Bay Times, October 24, 2017
  3. “Disease in trees pointed at in fires,” San Francisco Chronicle, October 20, 2017
  4. http://www.aphis.usda.gov/plant_health/plant_pest_info/pram/downloads/pdf_files/usdaprlist.pdf
  5. http://www.rcdsmm.org/wp-content/uploads/2016/04/Drought-and-Invasive-Beetle-impacts-RCDSMM-1.2.18.pdf
  6. http://ucanr.edu/sites/oak_range/Californias_Rangeland_Oak_Species/Coast_Live_Oak/
  7. Dov Sax, “Equal diversity in disparate species assemblages:  a comparison of native and exotic woodlands in California,” Global Ecology and Biogeography, 11, 49-52, 2002. http://elkhornsloughctp.org/uploads/files/1109813068Sax2002.pdf
  8. Robert Stebbins, “Use of Habitats in the East Bay Regional Park by Free-living Vertebrate Animals,” August 1975. In “Vegetation Management Principles and Policies for the East Bay Regional Park District,” June 1976 (this unpublished study is available on request)
  9. “Focused Environmental Study, Restoration of Angel Island Natural Areas Affected by Eucalyptus,” California State Parks and Recreation, July 1988, pg 96-97.
  10. http://climatereadytrees.ucdavis.edu/

A Milestone for Million Trees

As the Million Trees blog approaches the anniversary of its eighth year, we are celebrating a milestone. Yesterday, Million Trees reached a total of 250,000 individual views of posts on Million Trees.  We now have over 300 subscribers and we are averaging about 150 views per day.  About 25% of our readers are outside the United States.  Since nativism in the natural world is an international fad, we are gratified that Million Trees is being read by people in other countries.  Million Trees is also proud and grateful for the participation of several academic scientists who have written informative guest posts for Million Trees in the past year.  Thank you, Dr. Matt Chew, Professors Mark Davis and Art Shapiro, and Dr. Jacques Tassin for your help!

Our most popular posts have each been visited by over 10,000 readers.  They are, in the order of their popularity:

  • “Darwin’s Finches: An opportunity to observe evolution in action.”  This article about the speed with which adaptation and evolution occur in a rapidly changing environment is the bedrock of the Million Trees blog.  Nativists mistakenly believe that evolution is much slower than it is.  Therefore, nativists believe plant and animal species are nearly immutable and that they are locked into mutually exclusive relationships, which are, in fact, extremely rare in nature.
  • “Nearly a HALF MILLION trees will be destroyed in the East Bay if these projects are approved.” The Million Trees blog was created to inform the public that nativism is destroying our urban forest in the San Francisco Bay Area.  Our urban forest is composed of predominantly non-native trees.  If they are destroyed, we will not have an urban forest because native trees will not survive in our changed and rapidly changing environment.  Non-native trees were planted here because people wanted trees and native trees existed only in riparian corridors where they were sheltered from the wind and there was sufficient water.
  • “Falling from Grace: The history of eucalyptus in California.”  Because people wanted trees, they planted non-native trees that were capable of surviving in the San Francisco Bay Area.  Non-native trees were valued for nearly one hundred years until nativism got a death grip on our public lands. This article on Million Trees tells the history of why eucalypts were planted and why they “fell from grace.”

In the past year, one of the most popular posts on Million Trees was “Krakatoa:  A case study for species dispersal.”  This post has been viewed by over 7,000 readers.  Understanding how plants and animals were dispersed around the world by natural means–such as by birds, wind, and ocean currents—is another way to realize that the concept of “native vs. non-native” is an artificial construct with little practical meaning.  Plants and animals have always moved and they will continue to move.  In fact, as the climate changes, they MUST move if they are to find the environmental conditions in which they can survive.

Million Trees Commitment

Million Trees will continue to advocate for the preservation of our urban forest in the San Francisco Bay Area.  Our strategy is to inform the public of the many projects that are destroying our forests and to describe the damage that is being done by those projects.  We are particularly concerned about the use of pesticides to eradicate non-native plants and trees.  We are equally committed to providing our readers the latest scientific discoveries that relegate invasion biology to a scientific back-water.  We are hopeful that the gap between public policy and the scientific knowledge discrediting invasion biology will eventually be bridged and bring an end to this destructive fad.

Public reactions to conferences on invasive species are always illuminating

I am publishing a guest post by Jacques Tassin, who tells us of his personal experiences with presenting his findings about invasive species in public forums.  Jacques Tassin is a French ecologist. He has been working on invasive species for more than twenty years, especially on islands in the West Indian Ocean and Pacific Ocean.

Jacques Tassin

Dr.Tassin agreed to tell us about his interactions with the public because he believes the public’s views of invasive species are poorly understood and that improved understanding of the public’s views would improve communication about this controversial topic. 

I must add that my personal experiences with such interactions have revealed the same themes.  The public feels strongly that it is possible—even necessary—to control nature.  And much of that sentiment is based on guilt about the damage that humans have done to nature and a desire for redemption.  I prefer to respond to that viewpoint by informing the public of the damage being done in the name of “restoration.”  We cannot redeem ourselves by doing yet more damage.  However, I share Dr. Tassin’s frustration with scientists who are unwilling to speak to the public in ways that the public can comprehend.

Jacques Tassin is a new voice on Million Trees.  I am grateful for his participation in our discussion of invasion biology.

Million Trees


It takes much energy for a scientist to go down to the arena to meet the general public, for example in the form of a conference. But it is well worth it. On the one hand, because it allows scientists to hear a different kind of discourse than media coverage of the issue. On the other hand, because the comments and questions from the public are often very significant.

Following the publication of my book La Grande invasion: qui a peur des espèces invasives ? (The Great Invasion: Who Fears Invasive Species?) published in editions Odile Jacob in 2014, I was often invited to such meetings. I can distinguish several types of public reactions to my conferences.

The main one is the public’s seeming intolerance of the idea that we can agree to do nothing about the progression of an invasive species, even if it is proven that nothing can be done about it, or that the species in question does not have a clearly negative ecological or economic impact. Farmers and hunters are particularly opposed to this view of not intervening and therefore not controlling the environment. For these people, it is a question of putting nature in its place.

The public also strongly rejects the possibility that we cannot redeem our faults, or that we may not be able to undo what we have done, if we do not deal with invasive species. This reaction is the result of an activist stance that is particularly present in nature conservation associations. The remark that comes up most often is “we’re not going to sit back and watch.”

Finally, the third most frequent reaction is the belief that each invasive species introduced somewhere necessarily takes the place of another species. This principle of musical chairs seems deeply rooted in everyone’s mind. It is not certain that this is due to the theories of Robert MacArthur and E.O. Wilson’s about island biogeography. It seems much more likely that, deep in our imagination, the arrival of an intruder will end up with the departure of one of us.

In any case, it seems to me that the debate about invasion biology is far more concerned with social psychology than with the science of invasions. I am now certain that those who focus their discourse on the biological and ecological dimension of invasive species are headed in the wrong direction. Today, invasion biology is more in the field of psychology and beliefs than it is a question of a rational discourse. But it is clear that scientists are particularly ill-suited for this dialogue. Journalists who are used to talking to hundreds of thousands of listeners on the radio or in the press are much better equipped to do so. Scientists must learn from journalists how to communicate with the public about invasive species, whatever the public’s opinion of invasive species.

Jacques Tassin

Further Reading:

Tassin J., Thompson K., Carroll S.P., Thomas C.D. (2017). Determining whether the impacts of introduced species are negative cannot be based solely on science: a response to Russell and Blackburn. Trends in Ecology and Evolution, 32 (4) : 230-231.

Tassin, J. and C. Kull (2015). Facing the boader dimensions of biological invasions. Land Use Policy 42 : 165-169.

Tassin, J. (2014). La grande invasion. Qui a peur des espèces invasives ? Editions Odile Jacob. Paris, 216 p.

Beyond Pesticides: The voice of reason about pesticides

Beyond Pesticides logo

I attended my first Beyond Pesticides forum in 2014 in Portland, Oregon.  I have been a member of and donor to Beyond Pesticides ever since.  And I have purchased only organic food since attending that forum, because of a field trip to a community of farm workers that convinced me that growing our food without using pesticides benefits both consumers and producers of America’s food.  

In a recent letter to the National Invasive Species Council, Beyond Pesticides describes their organization and mission:

Founded in 1981 as a national, grassroots, membership organization that represents community-based organizations and a range of people seeking to bridge the interests of consumers, farmers and farmworkers, Beyond Pesticides advances improved protections from pesticides and alternative pest management strategies that reduce or eliminate a reliance on pesticides.” (The letter is available HERE: Beyond Pesticides – ISAC Comment )

 I receive emails from Beyond Pesticides at least once a week, alerting me to opportunities to influence the laws and policies that regulate pesticide use in America.  As you might expect, the frequency of those alerts has accelerated a great deal in the past year, as the federal government is actively engaged in the process of dismantling many federal regulations, including those that regulate pesticides.

 The National Invasive Species Council recently invited the public to submit public comments in answer to a few specific questions, in preparation for the next meeting of the Invasive Species Advisory Council.  Today I am publishing an excerpt of the letter of Beyond Pesticides in answer to those questions (some emphasis added).  I am doing so because I consider this letter a wise and informed critique of the entire concept of “invasive species” and the pesticides used to eradicate them.

 I am also alerting the readers of Million Trees to the opportunity to attend the annual forum of Beyond Pesticides in Irvine, California, April 13-14, 2018.  Information about that meeting is available below.

 Million Trees


“The National Invasive Species Council (NISC) posed four questions for public input to the forthcoming meeting of the Invasive Species Advisory Council (ISAC). We find it most helpful to begin with the fourth: “How can NISC foster the development and application of innovative tools and technologies to enable the prevention, eradication, and control of invasive species in a more timely and effective manner?”

In order to address this question, NISC and ISAC need to first address the question, “What is an ‘invasive species’?”

‘Invasive species’ have frequently provided a reason for dispersing toxic chemicals in the environment, often with a sense of urgency and an assumed indisputable benefit. This unsupported (and sometimes unstated) assertion of benefit is a claim to virtue that allows environmental harm instead of preventing it.

In the context of other federal, state, and local laws, the regulatory definition of ‘invasive species’ gives broad authority to agencies to use all means at their disposal to rid the jurisdiction of non-native organisms causing economic harm, as well as harm to health and the environment. Many local ordinances that ban or restrict pesticide use make an exception for ‘invasive species,’ presumably under the mistaken assumption that in doing so they are protecting the environment. Instead, they are allowing environmental harm through the spread of toxic substances.

The use of the term ‘invasive species’ as a claim to virtue that is used to promote any and every attempt to exterminate any unwanted organisms is very disturbing. It is important to understand the problems that lead to the use of toxic chemicals, beginning with the cause. In the case of situations involving so-called ‘invasive species,’ we find that few, if any, involve species that are truly ecologically invasive—that is, capable of invading and persisting in intact ecosystems. Instead, such situations usually involve species that can take advantage of disturbed habitats (‘weeds’ or ‘weedy species’). As such, the emphasis should be placed on healing the disturbance (to which end, so-called ‘invasives’ may sometimes be helpful), rather than killing the opportunist colonizer.

We do not take the position that such opportunist colonizers should never be removed or managed. We do believe that the decision concerning whether such action should be taken should be based on the situation at hand and not on a claim to virtue that makes extermination of non-natives a righteous cause.

Redefining ‘invasive species’ to be limited to those species that can invade and damage intact ecological communities will directly ‘foster the development and application of innovative tools and technologies to enable the prevention, eradication, and control of invasive species in a more timely and effective manner’ (NISC) because resources will be directed only at those species that truly present an ecological threat. It will prevent those resources from being squandered in ways that are ecologically destructive.

The sharper focus that this redefinition will bring to the NISC and ASIC will enable them to explore approaches such as those that Beyond Pesticides has used in working with National Parks, local governments, and tribes to manage ecological problems in a way that is truly protective of biodiversity.”

Terry Shistar, Ph.D.
Board of Directors
Beyond Pesticides


Beyond Pesticides will soon hold its annual forum in Irvine, California, April 13-14, 2018.  As usual, the forum will include highly qualified speakers who are knowledgeable about so-called “invasive species,” and the evolutionary principles that raise questions about the necessity and futility of trying to eradicate them.   Two of the speakers are important to our local effort to stop the use of pesticides to eradicate non-native plant species:  Dr. Scott Carroll and Professor Tyrone Hayes.

Dr. Scott Carroll is an evolutionary biologist affiliated with UC Davis.  He has published several influential studies about the speed of adaptation and evolution that enables introduced plants to join native ecosystems without long-term negative consequences of their introduction.  He has coined the concept of “Conciliation Biology,” which advocates that we turn from efforts to eradicate non-native species in favor of a new approach which manages the co-existence of native and non-native species. 

Professor Tyrone Hayes (UC Berkeley) is best known for his criticism of the herbicide, atrazine, which is harmful to the frogs that he studies.  Unfortunately, Professor Hayes’ opposition to atrazine does not extend to the pesticides being used in the San Francisco Bay Area to eradicate non-native trees and prevent them from resprouting.  Professor Hayes accepts the premise that eucalyptus trees are detrimental to native plants, which justifies the use of herbicides to destroy them, in his opinion.  The herbicide that is used for that purpose (Garlon with active ingredient triclopyr) is just as toxic as atrazine.  Both are organochlorine products that bioaccumulate, persist in the environment for decades, and are endocrine disruptors. 

The Beyond Pesticides forum is likely to generate some lively discussion of the issues that are relevant in the San Francisco Bay Area.  Details about the conference are available HERE.  Beyond Pesticides makes every effort to make these forums affordable for activists.  I have attended two of these conferences.  They were excellent opportunities to learn more about pesticides, to meet other activists, and to get ideas about how to advocate more effectively for more responsible pesticide use in our community.

I am very grateful to Beyond Pesticides for their leadership in the effort to reduce pesticide use in the United States.  They are a reliable source of information about pesticides and their activism is an inspiration to those who are engaged in this effort on a local level.

Million Trees

Were the real Nazis “native-plant” Nazis?

We recently published an article about the conference of the California Native Plant Society that featured this concluding photo of Doug Tallamy’s presentation opening the conference on February 1, 2018.

Doug Tallamy’s closing photo, CNPS Conference 2018

This photo generated some discussion among the readers of Million Trees about nativism in the natural world.  Is it related to nativism in the human realm?  This is a timely question because American politics are presently consumed by anti-immigration sentiment, AKA “nativism.”  As members of our communities are unceremoniously rounded up in immigration raids and deported from America, this is an association that is getting more attention.

We are pleased to publish a guest post by Professor Art Shapiro (UC Davis) in answer to this question.  Although Professor Shapiro is a renowned expert on the butterflies of California, he is knowledgeable on a wide range of subjects, including philosophy and history. 

Professor Shapiro offers us a nuanced answer to the question at hand.  This is an example of a general principle about such debates:  the more we know, the more complicated every issue becomes.  I have had the pleasure of a few long conversations with Professor Shapiro that were similar experiences. Professor Shapiro teaches us that we must examine issues from every angle, considering the pros and the cons.  More often than not, we can’t reach a definitive conclusion that does the issue justice.

But I will demur on the issue of nativism.  I will venture my opinion that nativism in the natural world is ultimately as pernicious as nativism in the human realm.  They both do more harm than good.  They are both fundamentally unjust.  However, I do NOT generalize about the motivation of native plant advocates. I doubt that the majority are appropriately called “native-plant Nazis.” 

I remain grateful to Professor Shapiro for sharing his knowledge and wisdom with me and with the readers of Million Trees. 

Million Trees


Various observers have noted similarities in the rhetoric used by native-plant activists and that used by xenophobes. The comparison has generated a derisive term, “native-plant Nazis,” to describe the most strident of those opposed to the use of non-native plants in gardens. But were the real Nazis “native-plant Nazis?” The answers are rather complex and in some ways surprising.

The German Romantic Movement stressed the “organic unity” of the German people and their landscapes. In 1818 the artist Friedrich Ludwig von Sckell in his book Beitraege zur bildenden Gartenkunst (“Contributions to Instructive Garden Art”) prescribed the planting of “patriotic species” to create landscapes of “patriotic character.” The great explorer-naturalist-geographer Alexander von Humboldt referred in 1806 to vaterlaendische Pflanzengestalten (plant character reflecting the Fatherland) and stressed that “the natural character of different regions of the earth is most intimately connected with the history and culture of the human race,” a notion that persists today, as witness the excellent book Landscape and Memory, by the historian Simon Schama, and is not in itself reflective of xenophobia.

During the Romantic period the intense longing for the unification of the fragmented German polity bred not only intense patriotic feeling but a concomitant disdain for the alien. Thus Fichte argued that the Germans’ “natural disposition to freedom dates back to prehistoric times, when they had been a pure and untainted race…before the influence of foreigners and the introduction of class division.” After the establishment of the First Reich in 1871, all things German were ever more aggressively touted as superior to all else, and this included landscapes. The writer Willy Pastor and the art historian Josef Strzygowski enthusiastically promoted these ideas in the early 20th Century. Pastor invoked the Ice Age as the crucible in which the German national character was forged; the glaciers “not only influenced the racial breed of humans, but also selected trees and plants….the European primeval forest, which finally evolved as the strongest out of this severe school, was no less of Germanic, Nordic race than the people…”

Nature garden designed by Willy Lange

The quintessential embodiment of such ideas was the work of the landscape architect Willy Lange. Lange and Pastor were friends and shared their nationalistic vision. Pastor published a collection of essays entitled Lichtungen (clearings) and a book The Earth in the Time of Man, in which he argued that the natural habitat of the true Teuton is a clearing in the forest. Lange translated that view into a prescription for garden design: he utterly repudiated the formalism of most European gardens and argued instead that the ideal form of garden was a well-designed, visually pleasing simulacrum of a natural forest clearing, employing whenever possible (but not exclusively) native plants characteristic of the natural landscape. His ideas were taken up by Alwin Seifert, who rose after the Nazis came to power to be the ultimate arbiter of garden design.  In 1939 Hans Hasler’s book Deutsche Gartenkunst (German Garden Art) spelled out the essential unity of the German national soul and the surrounding environment. Heinrich Friedrich Wiepking, who held the landscape design chair at the College of Agriculture in Berlin during the war, taught this doctrine as the rationale for gardening and invoked ancient Teutonic artifacts, burial mounds, and such as proof of this essential “organic unity.” Wiepking’s student Werner Lendholt “proved” that Germans already had a refined sense of landscape unity in the Bronze Age.

The idea of the “nature garden” arose repeatedly as a byproduct of romanticism, not only in Germany but throughout Europe and even in America; it can be seen as a reaction against formalism, with its rigidity and symmetry. But only in the Reich did it become so tightly fused with nationalism. There is nothing inherently political in Lange’s definition of his philosophy as “the derivation of ideas from nature and their translation in an artistic manner into garden design.”

Lange and his successors drew inspiration from the earlier work of the Irish garden writer William Robinson, who in turn was influenced by Gertrude Jekyll. And they in turn were influenced by William Thompson, who promoted the idea of the semi-natural “English flower garden” as early as 1852. The Austrian Robert Gemboeck, beginning in the 1880s, advocated “the reproduction of nature in the garden,” and was quite influential; he gave detailed prescriptions for how to create a simulacrum of wilderness—what kind of wilderness being dependent on the soil type available.

But none of this meant that the German garden had to be composed exclusively of native plants!

The era of both Robinson and Lange was the era of the “grand tour,” and both men traveled widely and assimilated their observations into their concepts of the natural garden. Lange’s disciple Hasler wrote that the master developed his art “as a result of his experiences and knowledge he gained on a north-south tour of Europe and North Africa.” After 1907 he explicitly advocated the introduction and naturalization of plants he regarded as esthetically in harmony with the true Teutonic landscape. During the 1930s the Nazi regime, primarily under the guidance of Heinrich Himmler, sponsored a series of famous expeditions to the Himalaya. There were several reasons for doing so. Himmler was entranced by the crackpot Welt-Eis Lehre (world ice theory) of Hanns Hoerbiger, which amplified the Romantic notion of the Ice Age as the crucible of German character. Himmler was interested in learning as much as possible about the Ice Age by studying what he viewed as the people living most like the ancient Teutons: the Tibetans, whom he imagined to be a pure and unadulterated race. But a subsidiary objective of the expeditions was to collect living material of Himalayan plants deemed suitable for naturalization in the Fatherland. In a sense, this represented an attempt to restore an imagined Edenic past.

Only those non-native plants judged to be inconsistent with the German landscape-character nexus, as largely defined by Alwin Seifert, were to be excluded. Seifert’s official title was Reichslandschaftsanwalt, or national landscape advocate. When he first received the title he presented two proposals to his superior, Fritz Todt: one embraced the use of non-native plants while the other did not. Seifert is a complex and problematic figure. He was anti-Semitic but never a really enthusiastic Nazi and he had a strong independent streak which often led him into trouble. He was a passionate advocate of organic gardening and sympathetic to anthroposophy, the cultish philosophy of Rudolf Steiner (today best known for the Waldorf School movement). His many contradictions led his biographer Thomas Zeller to call him “The Nazis’ environmental court jester and Cassandra, rolled into one.” His attitude on non-native plants hardened somewhat late in his tenure, when he took to calling Colorado blue spruce “public enemy #1.”

There was much in German garden philosophy and design to be admired, if one strips out the pugnacious racial and nationalistic rhetoric. There is really little difference from the natural-garden traditions developed elsewhere. Nazi Germany, early in its history, enacted what would today be characterized as the most progressive legislation in the world dealing with conservation, esthetics, and environmental health. Hence we have such books as The Green and the Brown and How Green Were the Nazis? that explore the contradiction between those facts and everything else we know about the regime. The contradiction becomes less bizarre when we remember the roots of Nazism in the Romantic movement.

At any rate, the real Nazis were never thoroughgoing “native-plant Nazis!”

Arthur M. Shapiro

Further Reading:

Bruggemeier, F.-J. and M. Cioc. 2005. How Green Were the Nazis? Nature, Environment and Nation in the Third Reich. Ohio University Press.

Uekoetter, F. 2006. The Green and the Brown: A History of Conservation in Nazi Germany. Cambridge University Press.

Wolschke-Bulmahn, J. 1992. The ‘wild garden’ and the ‘nature garden’ – aspects of the garden ideology of William Robinson and Willy Lange. Journal of Garden History 12: 183-206.

Wolschke-Bulmahn, J. 1997. Nature and Ideology: Natural Garden Design in the Twentieth Century. Dumbarton Oaks collection on the history of landscape architecture, vol. 18.

Highs and Lows of the 2018 Conference of the California Native Plant Society

I am pleased to publish the following report of one of our readers who attended the conference of the California Native Plant Society in Los Angeles at the beginning of February 2018. 

Million Trees


I attended the last conference of the California Native Plant Society in San Jose in January 2015.  It was interesting to note a few significant new themes in the recent conference in 2018.  Both fire and climate change were much more prominent themes in the recent conference.  While both are relevant to the future of native plants, neither seemed to have any effect on the “restoration” goals of the native plant movement.  For example, there were several presentations about massive die offs of native oak trees, resulting from higher temperatures, drought, and disease.  These presentations ended with urgent pleas to plant more oaks.  That seemed a fundamental contradiction and a denial of the reality of climate change.  When the climate changes, the landscape changes, but native plant advocates are not willing to acknowledge that.  In fact, the greater the threats to native plants, the greater the commitment to their preservation and “restoration.”

Beautiful pictures support nativist ideology

The conference began on a low point for me, but a high point for most attendees of the conference.  The keynote speaker was Doug Tallamy.  He was introduced as a “rock star” of the native plant movement, and indeed he is.  His presentation was very effective in delivering his message, which is that most insects are “specialists” with mutually exclusive relationships with native plants that evolved over “tens of thousands of years.”  If you believe that claim, you also believe that the absence of native plants will result in the absence of insects and ultimately the collapse of the entire food web.

Doug Tallamy’s closing photo, CNPS Conference 2018

Most native plant advocates believe that gloomy scenario, but few scientists still do, which creates a tension within this community of native plant advocates composed predominantly of amateur “botanists” and a smattering of academic ecologists.  For example, one of the first presentations after Tallamy’s keynote was an academic ecologist from UC Berkeley who advocated for accommodating the movement of plants outside of historical native ranges to accommodate climate change. (1) He said that restoring only with local natives is “maladaptive” and that a bioregional perspective is needed to create sustainable landscapes.  Allowing Monterey pines to grow in the San Francisco Bay Area, where they have grown in the past and are presently deemed “native” just 150 miles away, seems a good example of such a broader definition of “native.”  An amateur nativist, parroting Tallamy, asked this hostile question: “But if we move the plants how will wildlife survive?”  The academic delivered this tart dose of reality: “There are few mutually exclusive relationships in nature.  Wildlife will also move and will adapt to changes in vegetation.”

Science debunks a myth about eucalyptus

The high point of the conference for me was a presentation by Jennifer Yost, Assistant Professor at Cal Poly, San Luis Obispo.  She and her graduate student studied the claim that nothing grows under blue gum eucalyptus trees because of allelopathic chemicals emitted by eucalyptus that suppress the germination of other species of plants.  Two studies of this hypothesis were done in the 1960s, but the analytical methods used by those studies were misleading.

CNPS Conference 2018

Rigorous methods used by Yost’s team included planting seeds of 5 native plant species in the soil of eucalyptus forests and comparing germination rates of seeds planted in the soil of oak woodlands.  They also tested the effect of blue gum volatile leaf extracts, and water-soluble leaf extracts on germination and early seedling growth.

They concluded, “In these experiments, we found that germination and seedling growth of the species tested were not inhibited by chemical extracts of blue gum foliage, either at naturally-occurring or artificially concentrated levels.” (2)

CNPS Conference 2018

Yost observed that the lack of allelopathic effects of blue gum on the soil implies that blue gum forests theoretically can be successfully planted with native plants after removal of the trees.  However, she cautioned that those who destroy the blue gums should carefully consider what will replace them.  Will an aggressive non-native weed quickly colonize the bare ground?  If so, what is the benefit of destroying the blue gums? 

I had a conversation with one of the most influential nativists in the San Francisco Bay Area after Yost’s presentation.  This new scientific information does not alter his commitment to destroying blue gum eucalyptus in the Bay Area.  After all, there are many more negative claims that remain unchallenged by scientific studies.  For example, there are no studies that prove that blue gums use more water than native trees, as nativists claim.  Nor are there any studies that prove that eucalyptus leaves contain less moisture than the leaves of native oak or bay laurel trees, which theoretically makes eucalyptus more flammable, as nativists claim.  The lack of scientific evidence enables the persistence of speculation justifying irrational fear of blue gum eucalyptus.

Nativism dies hard because of lack of scientific studies

There appeared to be three distinct groups of people in the crowd of about 900 conferees.  There was a large contingent of grey-haired volunteers who are the backbone of every native plant “restoration.”  They are the dedicated weed pullers.  There is an equally large contingent of young people who are making their living writing the “restoration” plans and directing the activities of the volunteers.  The smallest contingent is a few academic scientists who study the underlying issues in their ivory tower.  The goals and conclusions of these three groups are increasingly divergent as scientific studies disprove the assumptions of the citizen “scientists.”

The tension between science and the citizenry is as evident within the native plant movement as it is in American politics at the present time. The general public rejects scientific evidence at its peril.  The rejection of science will not end well.  In the case of uninformed nativism in the natural world, the result will be a barren, poisoned landscape.


  1. “Climate change and open space conservation: Lessons from TBC3’s researcher-land manager partnerships in the San Francisco Bay Area,” David Ackerly1, Naia Morueta-Holme5, Sam Veloz3, Lisa Micheli2, Nicole Heller4 1University of California, Berkeley, Berkeley, CA, USA, 2Pepperwood, Santa Rosa, CA, USA, 3Point Blue Conservation Science, Petaluma, CA, USA, 4Peninsula Open Space Trust, Palo Alto, CA, USA, 5University of Copenhagen, Copenhagen, Denmark
  2. Abstracts of CNPS conference presentations are available here:  CNPS Conference abstracts

What is Compassionate Conservation?

Matt Chew has written another guest post for Million Trees about the International Compassionate Conservation Conference that recently took place in Australia, where he gave a presentation.  Dr. Chew is a faculty member of Arizona State University’s Center for Biology and Society and an instructor in the ASU School of Life Sciences.  He has written two popular posts for the Million Trees blog about the “restoration” industry and about the controversial projects that are eradicating tamarisk trees.

Arian Wallach, Dingo for Biodiversity Project

I was introduced to compassionate conservation by one of its proponents, Arian Wallach.  Dr. Wallach is the Project Director of the Dingo for Biodiversity Project in Australia.  Dingoes were the top predators of smaller animals in Australia for about 5,000 years until Europeans introduced new predators in the 19th century.  Colonists to Australia have been killing dingoes since they arrived because dingoes are also predators of their sheep. 

Eradicating top predators has serious consequences for the entire ecosystem.  In the case of dingoes, smaller predators introduced by colonists have taken that role and are now the target of poisonous campaigns to eradicate them.  For example, Australia recently made a commitment to kill 5 million cats with poison.  Killing dingoes has put Australia on the killing treadmill. 

We have examples in the United States of similar cascading effects of killing top predators.  When wolves and bears were killed in some of our national parks, populations of grazing animals such as deer and elk exploded.  Vegetation was browsed to death and ultimately the grazing animals were without sufficient food.

Dr. Chew tells us that defending top predators is one of several tenets of compassionate conservation.  Two important themes emerge from his description of the conference:

  • Traditional conservation tends to focus on the preservation of a species, sometimes at the expense of individual members of that species. Compassionate conservation invites us to re-evaluate that emphasis, to also take the lives of individual animals into consideration.  In an extremely individualistic society such as America, this would seem an entirely appropriate approach to conservation.
  • Modern methods of conservation tend to focus primarily on rare animals, sometimes at the expense of common animals. Common animals are often blamed for the fate of rare animals.  Shooting barred owls based on the belief that endangered spotted owls will benefit is an example of such projects. 

These are ethical questions that deserve our thoughtful consideration and Dr. Chew’s guest post invites us to think deeply about them.

Million Trees


The third International Compassionate Conservation Conference took place in Australia last November. Over 100 pre-registrants represented thirteen countries of current residence. Every occupied continent and a few archipelagoes were accounted for. Nearly half of the roster bore “Doctor” or “Professor” credentials. About two-thirds were Australian, one-sixth from the USA, and the remainder distributed in single digits. The final tally, including walk-in registrants, has not been compiled.

Some Background

Traditional resource conservationists and animal welfare advocates celebrate separate histories and espouse distinct philosophies. In a given circumstance their views may coincide, but they more often conflict. Sometimes it’s a mix of both. Professionals in either discipline are more attuned and (perhaps) committed to the distinctions than are members of the general public. Some advocates on both sides are more confrontational than others. Given all that, it may be unsurprising that the concept of compassionate conservation arose in the unique context of a British charity organized by the starring actors of the 1966 film Born Free. The predicament of Elsa the lioness they helped publicize provided a unique nexus of predator conservation and captive animal welfare to build on.  Their Born Free Foundation , which at one point actually trademarked the term “Compassionate Conservation” has helped underwrite three meetings: a symposium in Oxford, U.K. (2010); a conference in Vancouver, British Columbia (2015), and the most recent conference in Leura, New South Wales.

Leura, Australia

The latter two events were co-sponsored and organized by the Centre for Compassionate Conservation (Centre) at the University of Technology in Sydney (UTS). The Centre was founded in 2013 by UTS conservation biologist Dr. Daniel Ramp, who continues as its Director. His unusual goal, succinctly (indeed, laconically) stated, is “to better conserve nature by protecting the welfare of individual animals in captivity and in the wild.” The Centre currently lists a core management team of five, plus six affiliated researchers. Five conference attendees identified themselves as Centre Ph.D. candidates, and another as an unspecified Centre student. Before organizing the Centre, Daniel and most of his present colleagues comprised something called THINKK, focused more narrowly on ethical kangaroo conservation. Coincidentally, a documentary film emerging from that effort just opened in selected U.S. theaters.

Alloying animal welfare advocates and conservationists this way requires effort.  Alloying them into a fully coherent interest group is unlikely. Conservationists, including conservation biologists, are rarely concerned with the comfort or fates of individual organisms. For example, the Society for Conservation Biology is “dedicated to advancing the science and practice of conserving Earth’s biological diversity”. It emphasizes populations, species, biotic communities and other aggregations rather than individual organisms. This view accommodates Darwinian natural selection and economic sustainability of recreational and commercial exploitation, including so-called ecosystem services. Except where the population of some species is approaching zero and every extant individual contributes substantially to its genetic diversity, whether any of them are particularly well off beyond their ability to breed or produce gametes for propagation purposes is a subsidiary concern. By contrast, animal welfare begins with sentient organisms and recognizes fewer aggregate or emergent properties. Strictly speaking, to welfare advocates, preserving a species or population is secondary to protecting individuals from experiencing pain or suffering, especially that related to human actions or influences.

California Condor with tracking tags on wings

Logically extended, the difference between conservation and compassion can be illustrated by the California condor recovery effort. Condors incapable of breeding are useless to conservation biologists other than for public relations purposes. Any “display” animal is subject to the particular dangers inherent in repeated transportation and public contact. Presented as an example or representative of the taxon Gymnogyps californianus it nevertheless becomes a named or nicknamed individual entity in the minds of the people who “meet” it.  Once transferred permanently for display to (e.g.) a zoo, the welfare of a named, non-breeding condor takes on a significance that it never had before. Should it fall ill, hundreds or thousands of people will fret. Should it die unexpectedly, they will mourn and hold its keepers responsible. Meanwhile, potential breeding condors may be released to cope with hazards of “wild” survival their captive counterparts never face. The processes of breeding contribute further stresses and risks. The value of a display condor is tallied in goodwill and monetary contributions. The value of a breeder is tallied in viable offspring, much as the value of a laying hen is tallied in eggs produced. The contentment of a named bird is judged differently from that of a numbered one. Should “recovery” succeed, individual condors will someday become as anonymous as turkey vultures, their welfare officially unmonitored. With all that in mind, a compassionate conservation conference is necessarily a coalition exercise. A stable, hybrid entity like the UTS Centre remains exceptional.

In the Event

The three-day Leura schedule included ten presentation sessions, a poster session and six workshops. Each presentation session opened with a half-hour keynote talk from an invited speaker followed by a series of shorter contributions.

Presentations:

Australian waterfall

Presentation sessions were organized around conservation ethics (2); novel ecosystems (2); animal welfare science and issues (2); laws and policies; agriculture and wildlife, predator-friendly ranching and finally “cultivating compassion”. Keynote speakers (six men, four women) came from the USA (5), Australia (3), Malaysia (1) and the UK (1). Nine are university faculty or affiliates; two represent independent conservation NGOs (yes, we turned it up to 11). Few of us can comfortably label ourselves without hyphenating. Our credentials include (alphabetically) Animal Science, Conservation Biology, Ecology, English, Environmental Ethics, Environmental Science, Ethnography, Evolutionary Biology, History, Humanities, Law, Natural Resources, Philosophy, Wildlife Biology, and Zoology and doubtless some that I overlooked. Our keynote talks ranged from practical legal and management case studies to aspirational exhortations. That may not be a defensible continuum, but it will have to do.

A conference program with abstracts is available for download here. Since there were about sixty presentations over two and a half days, I can hardly even list them, much less say anything pithy about more than a few. Their diversity made for an intense, eclectic, even exhausting experience. The general quality of presentations struck me as higher than the average at many more traditional, disciplinary conferences. Perhaps it takes “more” of something or another to survive the rigors of interdisciplinary or multidisciplinary work.

What I can do is highlight a couple of impressive research projects of particular interest to Million Trees followers in the western U.S.  In his keynote address, Conservation as creative diplomacy: Raven and tortoise futures in the Mojave Desert, University of New South Wales Associate Professor of Environmental Humanities Thom van Dooren looked at “new technology” attempts to dissuade the big black birds from preying on juvenile, endangered reptiles. Artificial tortoises conceived as the equivalent to exploding, joke cigars featured heavily in this thought-provoking and entertaining analysis. Understanding introduced megafauna in the Anthropocene: Wild donkeys as ecosystem engineers in the Sonoran Desert by Arizona State University graduate turned Centre Ph.D. candidate Erick Lundgren showed how “feral” burros in western Arizona create water sources used by “native” wildlife by digging down to shallow aquifers in dry washes. Photos and infrared video made the case for this completely new and gratifying application of the term “ass holes” and discussion of the demonstrable positive effects of “alien” animals. An early presentation of Erick’s findings can be viewed here.

Posters:

Poster of Non-Nativist Landcare

For readers unfamiliar with poster sessions, the basic idea is to summarize a project, argument or proposal in the minimum necessary words and graphics to convey the important ideas. Posters can be perused at the convenience of conference-goers, and (as in this case) can be strategically hung in proximity to coffee and snacks; but a period is usually specified for poster authors to literally stand by their work and answer questions. What constitutes a poster is evolving rapidly. Mechanically pasted-up arrangements have been superseded by single, large format prints, which in turn may soon give way to looped or even user-navigable videos on flat screen displays. Only a handful of posters were presented at Leura. One included a description of low-disturbance riparian revegetation techniques; another explained a new proposal to legally protect captive whales, porpoises and dolphins in the U.S.A.; a third took data-driven issue with Argentina’s official over(?)-emphasis on lethally suppressing European rabbit populations; and the fourth combined a poster with a video loop to demonstrate the surprising calmness of red foxes living in proximity to dingoes, their only wild predators.

Workshops:

Befitting a gaggle of academics, three of the six workshops initiated collaborations meant to produce papers for peer-reviewed publication. “Welfare in the wild” focuses on the challenges of assessing the condition of free-living wild animals, a necessity for practical compassionate conservation. “The Australian Wildcat Project” seeks to reframe feral cats as wild animals and find “compassionate and effective solutions” that supersede traditional (and ineffectual) lethal culling.  “Transforming wildlife management policies” envisions a compassionate alternative to the present Australian Pest Animal Strategy.

For attendees not leashed to the “publish or perish” treadmill, “A framework for human-wildlife health and coexistence in Asia” built on the related presentation session to propose guidelines for further research and development. “Predator friendly ranching skills and technologies” demonstrated an array of time-tested, new and proposed methods for keeping livestock without resorting to lethal predator control. “Bringing ethics into conservation with argument analysis” offered an introduction to rhetorical and logical analysis of the claims underlying conservation decision-making.

Reflections

Banksia in Australia

On July 31, 1947, Aldo Leopold finalized a paragraph that appeared about seven eighths of the way through his introduction to a proposed book of essays. It began “One of the penalties of an ecological education is that one lives alone in a world of wounds.” There, Leopold styled himself as “the doctor who sees the marks of death in a community that believes itself well, and does not want to be told otherwise”. Perhaps ironically, less than nine months later (at age 61) he succumbed to heart failure aggravated by the exertion of fighting a grass fire, leaving the still unpublished anthology in other hands. Nearly two decades on, editors transplanted the paragraph into the much-revised text of a Leopold essay titled “The Round River” for re-publication by Oxford University Press, where his overwrought sentiment blossomed into a gnostic axiom of conservation biology.

Practically anyone could recognize an injured animal. Only Leopold, selected colleagues and their presumptive heirs could diagnose the arcane injuries of populations, species, communities or ecosystems. The welfare of an organism didn’t “amount to a hill of beans” next to the integrity of the greater collective. It was a more than convenient fit into the value system of academic biology, where individuals are traditionally considered mere examples of taxa, available for collection, experimentation, or “scientific” interference pretty much at will.

As a group, biologists have likely devised more (and more esoteric) ways than anyone else to kill, injure or discomfit organisms. Way back in 1865, physiologist Claude Bernard, fountainhead of the indispensable idea of homeostasis, reflected, “the science of life…is a superb and dazzlingly lighted hall which may be reached only by passing through a long and ghastly kitchen.” Recipes beyond his darkest dreams have since been tested there. In that regard, conservation biology is unexceptional. Conservation biology in practice consists largely of subsidizing the (Darwinian) fitness of too-rare species by forcibly taxing that of too-common ones. The move from culinary to macroeconomic metaphors indicates only that we are now cooking on a vast, institutional scale. Both figuratively and literally, conservation biologists break a lot of eggs in service of making too-rare species more common and supposedly too-common ones more rare. Consistent with basic economic wisdom, individuals of scarce species are more highly valued than those of common species. But much of biology is still concerned with examining formerly living objects to find out what experimenting on them accomplished. The drafters of laws like the U.S. Endangered Species Act made “experimental, nonessential” individuals or populations available for scientific “take”. At best, such exceptions allow for research that might stave of extinction. At worst, they provide cover for otherwise anathema activities like “scientific whaling.”

What will become of compassionate conservation? I can’t answer that question. Its advent represents an interesting cross-pollination among otherwise ramifying points of view. I’m sympathetic to the basic aims of its proponents. My own work wasn’t really conceived to abet them; but if it does, I say “well and good.” There’s more than enough casually rationalized cruelty in the world already. 

Matt Chew

Stevie Nicks, Naturalized Species, and the future of the biosphere

Professor Arthur M. Shapiro, at work, UC Davis

Art Shapiro is no stranger to the long-time readers of Million Trees.  Professor Shapiro is Distinguished Professor of Ecology and Evolution at UC Davis, and a renowned expert on the butterflies of California.  He is the author of a seminal, frequently cited study of California butterflies that reported the results of 30 years of observing butterflies in his research transects. (1)  He summarized this study in his Field Guide to the Butterflies of the San Francisco and Sacramento Valley Regions:

“California butterflies, for better or worse are heavily invested in the anthropic landscape [altered by humans].  About a third of all California butterfly species have been recorded either ovipositing [laying eggs] or feeding on nonnative plants.  Roughly half of the Central Valley and inland Bay Area fauna is now using nonnative host plants heavily or even exclusively.  Our urban and suburban multivoltine [multiple generations in one year] butterfly fauna is basically dependent on ‘weeds.’  We have one species, the Gulf Fritillary that can exist here only on introduced hosts.  Perhaps the commonest urban butterfly in San Francisco and the East Bay, the Red Admiral is overwhelmingly dependent on an exotic host, pellitory. And that’s the way it is.”

 Professor Shapiro has given us permission to reprint his Amazon review of the most recently published critique of invasion biology, Inheritors of the Earth, by Professor Chris Thomas (University of York, United Kingdom).  We recommend Professor Thomas’s book to our readers.  Although it is learned, it is accessible to the general public.  This book is another step forward in the long march to acceptance of the reality of existing landscapes that are adapted to present climate conditions.

 Million Trees


2011 Chris Thomas published a paper in the journal “Trends in Ecology and Evolution” entitled “Translocation of species, climate change, and the end of trying to recreate past ecological communities.” I immediately e-mailed him (April 11, 2011): “I have been delivering the same message in my advanced courses in Community Ecology and Biogeography for years, and have found the students by-and-large highly receptive, especially when they have internalized the overwhelming evidence for wild fluctuations in climate and vegetation since the end of the Ice Age 10-20,000 years ago. But over and over I have been told ‘but of course that is not the Party line…restoration ecology,’ blah, blah….Thank you for giving me a respectable citation, since merely citing one’s self can never do.” He e-mailed back: “…the conservation community in Britain seems mainly to be treating me with bewildered patience! I think that it will take time for everyone to become re-programmed to accept change as a reality.”

But of course change is not only a reality, it is the norm in ecology. Belief in equilibrium states and a “balance of nature” has been a dogma without a rationale beyond sentimentalism for many decades. There are coevolved segments of communities that are intimately synchronized and interdependent (say, figs and fig wasps or yuccas and their moth pollinators), but a great deal of any community is the product not of coevolution but of what Dan Janzen calls “ecological fitting,” whereby things haphazardly thrown together by the vicissitudes of geology, climate or commerce just happen to click. We are surrounded all over the globe by functioning communities and ecosystems with little to no history in geologic time. For about 40 years I have asked my students on their final exam how one might go about telling the difference between coevolved communities and “communities” assembled by chance. It is an exceedingly difficult question.

So this book is an expansion of the TREE [Trends in Ecology and Evolution] paper, and its message is vital. Resources for conservation are limited, and one must prioritize. The vast majority of naturalized alien species are harmless and many may be potentially beneficial. The ones that are genuinely harmful should be fought tooth and nail, but of course we do that anyway–we call it “pest management” and “public health.” The blanket indictment of “invasive species” makes no more sense than the blanket condemnation of human immigrants. Of course, when we say this, Thomas and I and Fred Pearce and “that Marris woman!” are immediately called out as shills for the extractive industries or the nursery industry or the Bilderbergers or the Zelosophists (conspiracy theory villains!!) or some despicable cartel of nature-haters. Pure poppycock. Truth-tellers attract trolls. That’s just the way it is.

Quite a few years ago a group of us took a prominent visiting British ecologist (not Thomas) on a field trip to the Sierra Nevada. We had half a dozen grad students and a few faculty crammed in a van. On the way up, one of the students sort-of apologized for the predominance of naturalized alien plant species in the lower foothill landscape. Our guest demurred forcefully: “Why must you consider this some kind of tragedy? Why don’t you see it as an opportunity for all kinds of evolutionary novelty to arise?” Indeed.
Thomas asks (p. 104): “How long will it be before the environmental police force of ecologists and conservationists is prepared to step back and decriminalize introduced species that have had the temerity to be successful?” An excellent question.

Stevie Nicks got over her fear of change: “Time makes you bolder…children get older…I’m getting older too.” Maybe conservationists can mature after all.

Arthur Shapiro


Professor Thomas’s book is very much in the mainstream.  The Economist magazine included it in their list of important books published in 2017.  It is one of only a few books in the category of “Science and technology” and it is at the top of the list.  The Economist says of the book, “Humans have consigned species to extinction at an alarming rate.  But hybridization and speciation is happening quickly too.  An ecologist at the University of York shows how humans are bringing about a great new age of biological diversity.  Extinctions ain’t what they used to be.”

The New York Times published a review of “Inheritors…” on New Year’s Eve.  The reviewer summarizes Thomas’s main argument: “He argues that new species are arriving and evolving faster than old species are dying out globally…Instead of the sixth extinction, it’s a sixth genesis.”  The reviewer faults Thomas for not portraying the “wonder of nature” and for giving oceans short shrift.  But, the reviewer concludes with this observation about the unhelpful role that humans often play in conservation efforts: “It is human concerns that determine everything here on Earth now.  An animal that arrived in a particular location hundreds or thousands of years ago is fine with us, while a more recent immigrant, like garlic mustard, is cause for alarm and extensive campaigns to extirpate the interloper.  Nostalgia is deadly, as people kill to preserve or restore some ill-remembered but more natural past, and we disdain new species as weeds.”  That observation about human attempts to control nature says it all.  Plants and animals are not to blame for the damage we are doing to satisfy our ideological commitment to the distant past. They are symptoms of change, not the cause of change.

Happy New Year!

Million Trees

Update:  Professor Thomas gave a presentation to the Long Now Foundation in San Francisco on June 19, 2018.  HERE is a video of the introduction to his presentation.
And HERE is a presentation at the National Academy of Sciences, “Moving Times for the World’s Biodiversity.”
If you haven’t read his book, his presentation is a good summary of the issues he covers in his book.  MT

Anise Swallowtail butterfly in non-native fennel. Courtesy urbanwildness.org

  1. Arthur M. Shapiro, “Exotics as host plants of the California butterfly fauna,” Biological Conservation,110, 413-433, 2003

Scientist says 50% of oaks in East Bay parks will be dead in 20 years

East Bay Regional Park District is in the process of selecting the projects that will be funded by the renewal of Measure CC, the parcel tax that has funded park improvements.  Measure CC will be on the ballot for renewal in November 2018 and will provide funding for “park improvements” for the next 15 years.  YOU can have some say about those projects by making your suggestions to the park district by the end of December.  Send your suggestions to publicinformation@ebparks.com.

The original parcel tax was passed in 2004.  Over 22% of the money raised by that parcel tax was used to destroy healthy non-native trees in the parks.  Meanwhile, many of our native trees, most notably our Coast Live Oaks, are dying of Sudden Oak Death.  Destroying our non-native trees, while our native trees are dying, predicts a treeless future for the Bay Area.  Since dead trees are more flammable than living trees, destroying living trees while leaving dead trees in the parks means that fire hazards are being increased.

We published a letter from a park advocate about Sudden Oak Death to the park district recently, which is available HERE.  Today we are publishing an update from the park advocate who has learned more about the dead oak trees in East Bay parks.  A scientist who is studying Sudden Oak Death in East Bay parks tells us that there are tens of thousands of dead oak trees in the parks and that the park district is not removing them.  The dead trees are now fuel for fires in the parks.  

It’s been a rough year and we are sorry to end it with this unhappy news about trees in the East Bay.  We send you our best wishes for a better year in 2018.  Thank you for your readership. 


Source: Brice McPherson, December 7, 2017

TO:                  Rick Seal, Fire Chief; Robert Doyle, General Manager; Board of Directors

CC:                   publicinformation@ebparks.org

FROM:            Park Advocate

RE:                  Please hire arborist/forester with Measure CC renewal

I attended the presentation of Brice McPherson to San Francisco IPM Technical Advisory Committee about Sudden Oak Death (SOD) on Thursday, December 7th.  Mr. McPherson is Associate Specialist in “Organisms & the Environment” at UC Berkeley.  He has been studying SOD since 2000 and more recently has inventoried the trajectory of the disease in 5 EBRPD parks and conducted experiments in those parks, with the park district’s permission.

Mr. McPherson began his study of SOD in Marin County, where SOD infections were first seen in 1994, before beginning his research in East Bay parks.  Comparing the progression of the disease from Marin County to the East Bay has enabled Mr. McPherson to project the future of SOD in the East Bay.

Wildcat Canyon is the park in which Mr. McPherson has inventoried infected and dead trees most recently.  In 2017, Mr. McPherson found that 16.2% of coast live oaks were infected and 20.5% were dead.  The number of dead and dying oaks in Wildcat Canyon is staggering:  18,750 oaks are infected and 21,360 oaks are dead.

Source: Brice McPherson, December 7, 2017

The number of dead and dying trees in the other 4 East Bay parks that Mr. McPherson is studying is smaller.  However, his inventories in those parks are much older. Since SOD infections have increased exponentially in 2016 and 2017, we should assume that his data underestimate the current status of oaks in those parks.  As you probably know, the pathogen that causes SOD is spread by rain and wind.  For that reason, the rate of SOD infections has soared during the past two wet winters.

Mr. McPherson predicts that the infection rate in Wildcat Canyon will increase 10.2% per year in the future, causing 10,600 new infections per year.   Mr. McPherson predicts that +/- 50% of all coast live oaks will be lost in East Bay parks in the next 20 years, resulting in “major changes in stand structure.”  In other words, most oak forests will be replaced by other vegetation types.

Source: Brice McPherson, December 7, 2017

In response to a question, Mr. McPherson said that the park district is not doing anything about the dead oak trees because there are not sufficient funds available to remove the dead trees.  He was also asked how the dead wood can be removed without spreading the infection and/or creating piles of dead fuel throughout the parks.  He could not answer that question.

This new information requires that I repeat what I have written to you on earlier occasions:  “These changes in the environment require the park district to revise its strategies for fire hazard reduction because dead trees are significantly more flammable than living trees that contain more moistureRemoving trees infected with or killed by Sudden Oak Death should now be a higher priority than continuing to destroy healthy trees, as the park district has done in the past.  Protocols for removing the dead wood must be developed because the wood is fuel when left on the ground…”

As you know, the park district has spent about $22 million dollars destroying healthy, living trees in the parks with Measure CC funding.  If the park district has the money to destroy living trees based on the claim that it will reduce fire hazards, it obviously has the money to remove dead fuel in the parks.

Finally, we learned from Mr. McPherson that the park district does not employ a single certified arborist or forester.  Given the resources the park district devotes to native plant “restorations” and spraying pesticides, surely it can also employ someone who knows something about trees.  The landscape in the East Bay is undergoing a radical change to species that are adapted to current climate conditions that, sadly, will replace our beautiful oak forests.  We need the guidance of qualified arborists to identify the most hazardous trees and make the transition to a new landscape.  The employment of such expertise about trees would be a worthy expenditure of new Measure CC funding.

Thank you for your consideration.