“We planted a forest!” – The mental health benefits of ecological restoration: a pilot study

By Suzanne Hicks, Ecological Health Network, Gondwana Link. Suzanne Hicks is a clinical psychologist from Margaret River, Western Australia, with an interest in how nature influences our mental health. Here, she describes the evolution of an innovative pilot project involving disengaged young people in ecological restoration work with the intention of improving their mental health. The novel experimental design allowed her and her colleagues to test the hypothesis that there is a causal link between the observed improvements in social anxiety of the participants and the ecological restoration work undertaken by them.

An intriguing discussion in 2020 with James Aronson, of the global organisation Ecological Health Network (EHN), about the links between ecological restoration, soil health, and human health, whetted my curiosity to attend the second workshop in Hobart, Tasmania in February the following year. Although a clinical psychologist, rather than a scientist or ecologist, I have long been aware of the ways that being out and about in nature has a positive impact on mental wellbeing, both mine and that of my patients. But I wanted to learn more about the mechanisms by which this might occur, and also to be part of the growing movement involved in the regeneration of degraded landscapes and restoration of habitat.

In the days prior to the conference, we visited a site in the North East Bioregion of Tasmania where a group of unemployed people, brought together by Todd Dudley, president of the North East Bioregional Network, had undertaken ecological restoration at the site of a former pine plantation. Over 700 hectares of harvested, burned plantation land had been restored to the trajectory of a thriving native forest recovering from several cycles of clearing and pine plantations.

Landscape immediately following clearing of pine plantation in the North East Bioregion of Tasmania, Australia (left), and the same landscape four years after initiation of restoration of the endemic forest ecosystem.

The scale and success of the Tasmanian ecological restoration project was impressive, but equally intriguing from my point of view was the reported improvement in the physical and mental health of the participants. Accounts of changes from apathetic, disengaged and unhealthy unemployed people to enthusiastic and fit workers, some of whom went on to do further study in forest management and ecological restoration and regeneration, piqued my interest. However, what also stuck in my mind was a comment made by James Aronson. While applauding the success of the project, he also remarked that “It may as well not have happened”. Puzzled, I asked him why. His answer – because there was no empirical research data to support its outcomes. The intuitively obvious link between being involved ecological restoration and improvements in human health was purely anecdotal. I held that thought…

I felt somewhat out of my comfort zone at the start of the Hobart workshop, sitting among a high-powered group of public health researchers and environmental scientists from Australasia and the United States. While passionate about nature and very committed, through my work, to helping people improve their mental well-being, I certainly didn’t have deep scientific understanding of the nexus between the two. However, I was welcomed by the group and soon found myself intrigued and stimulated by what I was learning about ecological regeneration efforts being undertaken around Australia and Aotearoa New Zealand, and the ways that human health is impacted by natural environments and healthy biomes. The take-home message was clear: being in nature is good for people. In particular, the restoration of riverbanks may have the biggest bang for buck, improving water quality and the downstream health of the people who use the water. Yet, again and again, the need for empirical evidence was emphasized.

There is an abundance of data attesting to improvements in human health from being in nature, and also for the positive impacts on the environment of improving biodiversity. However, when it comes to support for the hypothesis that being actively involved in ecological regeneration, in and of itself, improves human health and wellbeing, EHN’s Adam Cross informed me there appears to be only a handful of published papers worldwide. Of these, almost all are correlational, and rely on subjective measures of well-being. There is, therefore, an urgent need for empirical data to guide ecological restoration endeavors, and further, in these times of escalating health budgets, to attract funding for ecological restoration as an important public health intervention.

On the plane back to my home in rural Margaret River, Western Australia, I mulled over what I had learned and wondered how I might bring it to bear in my community. My academic training as a clinical psychologist prompted me to speculate on the ways one might empirically research the hypothesized link between healing activities for impaired ecosystems and psychological health.

The Margaret River Program

I am a member of a recently-formed group of volunteers, who call ourselves Mindful Margaret River (MMR). We are working to improve the mental health and well-being of people in our town, which has had its fair share of recent natural disasters and tragedies: serious bushfires in 2011 and 2021 that burned numerous homes as well as large areas of national parks, and a multi-generational murder/suicide that took seven members of a single family. In addition, I belong to our local Nature Conservation group (NCMR). I wondered if, under the umbrella of MMR, I might develop a program, drawing on the resources of NCMR, whereby disengaged students from our local high school were invited to be part of a 20-week ecological restoration program aiming to improve both nature and the participants’ mental health. The novel part of the program would be to allocate students to one of two groups, the first involved in ecological restoration and the other to be in actively working in nature but not specifically participating in restoration activities. Researchers from the Psychology Department of University of Western Australia (UWA) would be invited to empirically evaluate the outcomes of the program.

In collaboration with my colleague Sandra Robertson, a community nurse at the local high school, a twenty-week program was developed taking students from school one day per week under the supervision of two teachers. The program would be assisted by NCMR staff in the practical aspects of restoration work. Volunteers from the Cape to Cape Walking Track  would guide the second group in maintenance of this long-distance coastal hiking track. The program would be under the formal custodianship of the local Indigenous Peoples, the Wandandi Peoples, who welcomed the students onto their Country (an Australian term referring to the ancestral Traditional lands of an Indigenous group) and accompanied them for a number of days throughout the program to teach them about Indigenous lore and culture, and about caring for Country. Additionally, a number of people working in environmental science and management such as rangers, scientists, and artists, were approached to talk to the students about nature-based career options, and on other occasions the students heard from experts in various components and aspects of local biodiversity.

Wandandi cultural custodian Zac Webb drawing a map of Country for the participants of the high school program.
Students of the program learning simple survey skills prior to beginning restoration work.

Over the course of 2020 we secured seed funding for the project from EHN Hub Gondwana Link, and subsequently full project funding from the Western Australian state-based grants body, Lotterywest, to operate the program for a further two years. Following this success, our pilot program was launched in 2021. Twenty-four year 10 and 11 students were selected, semi-randomly, for the two groups. There were 17 boys and seven girls, and four of the students were Indigenous. Their average age was sixteen. Sadly, due to behavioral issues, after 12 weeks the group involved in track maintenance was disbanded.

Students were excited to record different species of fungi during biological surveys.

The regeneration group completed the 20-week program and three questionnaire measures of their psychological wellbeing, taken at three points in the program, were obtained and analyzed by the UWA researchers. Taken together with focus group information, the researchers determined that there had been a statistically significant reduction in the students’ social anxiety over the course of the program, and that they had developed a greater sense of connection with nature and more appreciation of the actions they could take as individuals to help preserve their local environment.

The Boodja (“Country”) Regeneration crew, on Country during their 20-week program.
The Biddi (“Coastal path”) crew, on Country during the program.

After the challenges of the pilot stage, more work is now being undertaken to modify the research model of the program to fit more smoothly within the framework and timetabling of the school curriculum. However, even at this early stage we are pleased to be able to begin demonstrating empirically the benefits for mental health of being involved in ecological restoration activities. We hope that the next stage of the program will build our evidence base further, developing strong empirical support for the health benefits of engaging with nature and participating in ecological restoration—towards a vision where such activities might even become a central aspect of learning and education. In the meantime, it was a delight to have the enthusiastic endorsement of our young participants, captured in the comment from one of them – “We planted a forest!”

Time to learn from the past: Indigenous Peoples are leading land management in Southwest Australia, and the rest of the world should take note

By Adam Cross. Western Australia faces a biodiversity crisis driven by climate change and inadequate conservation and land management. Rates of extinction here are already among the highest in the world, and government projects have struggled to improve the situation for most species. But as land management is increasingly being turned over to Indigenous Australians, successes have begun emerging from the ashes.

Western Australia is known internationally for its remarkable biodiversity and high levels of floristic endemism. It is a landscape of rugged natural beauty that supports among the most ecologically unique and highly specialised organisms on the planet, and in which occur some of the world’s oldest rocks, oldest living life forms, and oldest continuous human cultures. And, it is a landscape of extremes—not only environmental extremes, such as the contrast between the cool, wet forests of the southwest and the hot, dry deserts of the interior, but also extremes in human impact.

Curtin University PhD student Thilo Krueger undertaking a biodiversity survey in the seasonal wetlands near Esperance with Tjaltjraak Aboriginal Rangers. Such projects are examples of the highly successful cross-cultural learning between Indigenous and Western scientists that are increasingly underpinning land management in Western Australia. Photo: Zoe Bullen.

In the southwestern corner of the 2.6 million km2 state, the result of wholescale clearing of millions of acres of native forest and woodlands for broadacre agriculture, mainly in the 1940s–1970s but continuing today, can be easily seen from space. Flying over Western Australia’s Wheatbelt region can yield horizon to horizon views containing little more than scattered handfuls of trees in a vast ocean of yellow-brown. In large areas of the Wheatbelt, for example, less than 3% of the landscape remains covered by native vegetation. It is among the most extreme examples anywhere in the world of habitat destruction on an industrial scale in an astonishingly short time frame.

In contrast, in the remote north of Western Australia in a region known as the Kimberley, there remain vast wilderness areas of remote savannah woodland, among the most ecologically intact and least human-impacted ecosystems still in existence. Although globally some 70% of tropical savannah ecosystems have been lost, a vast 1.5 million km2 of them remain in northern Australia, mostly in good condition, of which nearly 350,000 km2 is in the state of Western Australia. Nestled within this seasonally-dry savannah are rivers and deep rocky gorges, extensive sandstone plateaus and uplands, rugged ranges, and a myriad of seasonal and wetland habitats, providing a complex suite of more mesic habitats supporting high levels of botanical endemism. Over half of the 3,000 plant species currently known from the region have been described scientifically in just the last four decades, highlighting how remote and inaccessible the Kimberley remains even today.

A huge pall of smoke rises from an intense prescribed burn in seasonally wet peatland ecosystems near Albany, September 2017, turning a bright spring midday into an apocalyptic scene. Photo: Adam Cross.

These extremes in human impact come with considerable challenges in how we manage, conserve, and restore biodiversity and ecological resilience. Not even the Kimberley region is immune from external anthropogenic threats: weed invasion and rangeland stocking levels are ongoing concerns, and mining activities impact some areas. Indeed, a copper mine proposed within 20 km of the iconic Horizontal Falls in the Kimberley archipelago is cause for concern. Apparently illegal track and exploration clearing at the site has already prompted outcry from tourism operators, environmentalists, and the general public. Conflict between development, industry, and environmental interests in this manner is common in Australia, and current approaches and legislation are far from doing a sufficient job of managing and maintaining the country’s unique natural environment.

After reportedly being buried for several months by the previous federal government, the recently published 2022 Australian State of the Environment Report paints a bleak picture of a continent’s ecosystems in ecological freefall. Vegetation loss due to land clearing continues at remarkably high rates around the country. Nearly 2,000 species are now threatened with extinction and some 19 ecosystems remain on the brink of complete collapse. Conservation and land management strategies are poorly coordinated and often fail. In addition, anthropogenic climate change is now recognised as a threat to every Australian ecosystem and is expected to compound the significant and growing impacts of numerous other threats and stressors.

The enormous smoke cloud from a prescribed burn darkens the sky over agricultural land near Margaret River, September 2017. Photo: Adam Cross.

Indigenous land management leaders

One of the very few positives presented by the 2022 State of the Environment Report, however, is recognition that Indigenous land management and the incorporation of Traditional Ecological Knowledge in environmental programs is having real, genuine benefits for biodiversity and the integrity of Australia’s ecosystems. Native Title, recognition by Australian Common Law that Indigenous Australians have cultural and historic land rights and interests, has resulted in over half of the Australian landmass being recognised as Indigenous estate. This means that now 54% of the National Reserve System of protected natural ecosystems consists of Indigenous Protected Areas and conservation reserves that are jointly managed by Indigenous Australians in partnership with other groups. In many cases, traditional approaches are returning to the management of Australia’s land and seas for the first time since European colonisation.

Cool fire-stick burns such as this one in open savannah woodland in the North Kimberley, April 2019, promote pyrodiversity by creating complex matrices of burnt and unburnt habitat in the landscape. Photo: Adam Cross.

Many around the world will have heard of the recent catastrophic bushfires spread across eastern Australia, caused by climate change coupled with changes in the way that we manage our native forests. These fires, impacting some 28 million acres, are estimated to have killed or injured over 3 billion native animals, and damaged many ecosystems to the point where their recovery remains uncertain. And, amid highlighting the growing urgency for improved management and increased efforts to undertake ecological restoration across the Australian landscape, they rekindled the vigorous debate over a controversial topic in Australia—prescribed burning. Many of the areas that burned intensely in the summer 2019/2020 fires had recently undergone prescribed burning regimes in an effort to reduce fuel loads, a practice undertaken throughout many Australian ecosystems despite mounting evidence of its inadequacy at achieving safety outcomes and significantly deleterious impact on native biodiversity.

Contemporary prescribed burning is often undertaken by dropping incendiaries from aircraft, complemented by drip burning around the edges of the target area to be burnt to ensure fire boundaries are maintained. It is also typically undertaken in winter and spring, when weather conditions are most conducive to ensuring that fires do not become uncontrollable, at fire return intervals of seven years (studies suggest natural fire return intervals in most Western Australian ecosystems are in the decades or centuries). Unfortunately, the reality of this strategy means that large areas of remnant bushland are repeatedly incinerated from the outside inwards, often during peak flowering and breeding season for most species of native flora and fauna. For example, a catastrophic prescribed burn in one of southwest Western Australia’s most biodiverse regions in March 2019 transformed over 2200 acres of biodiverse woodland into a desolate, blackened ‘morgue’. However, in some regions, land managers are increasingly turning to the Traditional Owners of the land, Indigenous Australians, to understand how fire might be better managed.

Cool fire-stick burns such as this one in open savannah woodland in the North Kimberley, April 2019, promote pyrodiversity by creating complex matrices of burnt and unburnt habitat in the landscape. Photo: Adam Cross

Indigenous Australians have employed traditional approaches to fire use and management for tens of thousands of years, particularly in fire-prone ecosystems such as the monsoon tropical grassy savannah of the Kimberley. Every year, around 40% of the vast 420,000 km2 region can burn. In recent decades, driven both by recognition of the inadequacy of Western fire management strategies and by Native Title returning the management of Traditional Lands into the hands of Indigenous Australians, Indigenous fire management has returned to the Kimberley. While many prescribed burns in the region are still undertaken by dropping incendiaries from a helicopter, much greater focus is being placed upon the timing and spatial arrangement of burning. This ensures the landscape comprises a complex mosaic of different burn ages, providing suitable habitat for native species that often possess very different fire resilience strategies. Indigenous fire management centres around lighting fires in the late wet season (March–July) rather than in the late dry season (October–December), resulting in cooler fires that burn slowly and remove fuel for more intense fires later in the dry season. Often these fires are lit on foot, a traditional practice referred to as ‘firestick farming’.

Even when fire from cool, early wet-season fire-stick burns does intrude into sensitive habitats such as this outcropping of sandstone pavement, the impacts are typically patchy rather than resulting in entire outcrops burning. Photo: Adam Cross.

As an indication of how cool the fires started by traditional burning practices can be, one can often step over the fire front as it passes slowly through the Savannah grasses; fire intensity several orders of magnitude lower than dry season fires that can individually burn millions of hectares and may burn for weeks at a time in rugged, remote country not at all conducive to firefighting. And, crucially, cool burns lit on foot typically result in remarkable ‘pyrodiversity’: crosshatch patterns of fire scarring representing complex mosaics of different fire ages, fire sizes, and fire intensities. Individual fire areas from this approach are often tens of square kilometres or less, and don’t homogenise the landscape in the same manner as huge dry season fires.

Example of a sandstone outcrop habitat following the passage of a cool late wet season burn, showing the patchiness of fire impacts and illustrating how these habitats often act as areas of fire refugia. Photo: Adam Cross.

For Indigenous Australians, ‘Country’ is inseparable from the people who live within and upon it. Indigenous land management aims to maintain healthy Country through the practice of cultural lore and activities, and traditional approaches to healing Country are increasingly recognised as a profound form of ecological restoration. Such activities are holistic, also achieving cultural and community healing, and are not limited only to terrestrial ecosystems: Indigenous approaches to restoration have also markedly improved the outcomes of restoration in seagrass and other marine and near-coastal ecosystems.

Indigenous land management initiatives, including the highly successful Aboriginal Ranger Program, appear to be taking strides forward in appropriately managing Australia’s threatened ecosystems and biota where many other initiatives continue to flounder or fail. For example, in 2017 the Auditor General’s Conservation of Threatened Species Follow-up Audit examined whether progress had been made on a suite of recommendations made during an environmental audit in 2009. It found that progress by the State Government department tasked with managing Western Australia’s biodiversity had been “disappointing”, noting that the department has “considerable work to do” and will “continue to struggle to show… that scarce resources are being effectively targeted to conserve our world-renowned biodiversity”.

Blackened stumps and bare soil, all that remain of biodiverse forest in Southwest Australia following a prescribed burn near Albany, 2019. Though a different ecosystem in another region from the North Kimberley savannah, the significant ecological impacts of intense, aseasonal prescribed burning are clearly evident. Photo: Amanda Keesing.

In 2009, 601 Western Australian species were threatened with extinction and 37% of these had recovery plans (strategies for improving their conservation status) in place. By 2017, another 71 species had been placed in the threatened list and 55% of all threatened species had recovery plans. But, as the threats to our environment have increased, staffing and expenditure on conservation and threatened species management by the State Government has fallen. Fortunately, this contrasts with an increase in funding for Indigenous land management programs, with nearly $AUD 37 million ($USD 25.8 million) committed to develop new Indigenous Protected Areas between 2018 and 2023 and over $AUD 746 million ($USD 521.5 million) allocated to support Indigenous Ranger Programs until 2028. There are lessons to be learned by Australian land managers around the country from the success of returning traditional Indigenous land management approaches to areas like the Kimberley, as the 2022 State of the Environment Report implies. We need to find a mixture of modern ways with the old ways. We need to adjust, or completely change, the way we approach land management in Australia across the board: not only in fire management but in appropriate stocking levels, weed control, regenerative farming practices, sustainable mining, conservation, and the restoration of areas that have already been degraded or destroyed. Unlike the Kimberley, where we are lucky that so much remains so intact, so many other ecosystems around Australia are in increasingly dire need. Hopefully, with Indigenous Australians leading the way, there is still enough time to conserve or restore them before it is too late. 

The low flames from a cool fire-stick burn lick through the still-green savannah grasses in the North Kimberley, April 2019. Photo: Adam Cross

Healing communities by healing country: First Nations peoples are increasingly leading ecological restoration programs for Australia’s threatened and degraded landscapes

Adam Cross, Keith Bradby, and James Aronson describe and discuss some of the 120+ Indigenous Peoples-led programs in Australia that are setting a benchmark for the sustainable and ecologically-responsible management of the nation’s unique natural landscapes.

In the 233 years since 1788, when European colonisation of Australia began, catastrophic environmental and social cost has been endured by Aboriginal and Torres Strait Islander communities. During the same period, the ancient continent’s megadiverse native ecosystems have been transformed or replaced at almost incomprehensible scale and speed. Much of the natural landscape has been dramatically and tragically altered by activities such as the agricultural and livestock husbandry practices imported by the new settlers, rampant deforestation, mining, and urban development, as well as poor fire management coupled with weed, animal and disease invasion. For example, in Western Australia, agricultural expansion by Europeans led to 97% of native vegetation to date being cleared from much of the 155,000 km2 (60,000 mi2) Wheatbelt area surrounding Perth—a short-sighted endeavour that has altered regional climate and left vast areas desertified, unproductive, and acutely affected by dryland salinity. What’s more, this industrial-scale exploitation, transformation, and degradation of natural ecosystems has not only caused great loss of biodiversity and ecological functioning, but also damage to human health and well-being—with the costs being borne disproportionately by Aboriginal and Torres Strait Islander communities. Yet, tragically, it is these First Nations peoples of Australia who are the custodians of an ancient multi-millennial cultural understanding that people are a part of nature and that the health of Country (vernacular in Australia for the natural or native landscapes) and its people are intrinsically intertwined.

Ecologist Jim Underwood and Nowanup Noongar Ranger Nigel Eades establishing camera traps to monitor wildlife movements on a property owned by Bush Heritage Australia. Photo: Nic Duncan.

In light of worldwide ecosystem degradation and decline, as well as increasing concern both in Australia and globally around the growing public costs of addressing mental and physical ill-health, there is growing awareness of the value and urgent need to link applied ecology and public health in recognition of the importance of healthy, biodiverse ecosystems to human society. 

In the terminology adopted by the EcoHealth Network, ecohealth is a concept that combines ecosystem health and public health as intertwined objectives with an emphasis on ecological restoration and allied activities (e.g., agroforestry, permaculture, regenerative urban planning and design, etc.). The science, practice, and policy of ecological restoration, when undertaken within an ecohealth approach, considers its implications for human health in a holistic way. Likewise, public health interventions imbued with an ecohealth perspective take into account the role of ecosystem health in impacting human health and reducing the risk of public health disasters. This framework differs from planetary health and One Health in that it is grounded in place-based ecological restoration of degraded ecosystems and the improvement of the human culture-nature connection. Thus, it addresses causes of ecosystem degradation and fragmentation, not just human and animal health-related symptoms and crises. The ‘ecohealth hypothesis’ posits that the restoration and rehabilitation of a degraded ecosystem will have significant health benefits for people who interact with that ecosystem, in present and future generations. However, there is nothing new in this concept for Aboriginal and Torres Strait Islander peoples. They have known of the value of more-than-human nature and its benefits for human health for tens of thousands of years. In fact, it is this deep cultural understanding that underpins the strong imperative for ecological stewardship, vis à vis their “country”, in Aboriginal and Torres Strait Islander culture. This foundational, and all-too-often forgotten, network of linkages between ecological and human health is captured, for example, by the cultural mindset of the Noongar and Ngadju Peoples of Western Australia, one of the oldest living cultures on Earth: “We are a people who look after country and the country looks after us” (Ngadju Elder Les Schultz).

Planting activities at the first Indigenous owned and managed native seed farm, in the Mid West region of Western Australia, aiming to generate native seeds to meet the demands of ecological restoration activities on mined lands throughout the region. Photo: Kingsley Dixon.

Healthy Country is a crucial determinant of physical, social, cultural, and spiritual well-being. There is a need to return to this and related ancestral Indigenous paradigms as we strive to live more sustainably towards a vision of a prosperous, healthier future (Bradby et al. 2021). Moreover, in practical terms, we need to find ways to create synergies between so-called Western, inductive science and ancestral Indigenous paradigms, ecological knowledge, and ways of knowing.

Nowanup Noongar rangers establishing wildlife camera traps with Bush Heritage Australia. Photo: Nic Duncan.

The quality and integrity of the ecosystems within which Aboriginal and Torres Strait Islander people live, and of which they see themselves as an inseparable component, is central to lore and culture. “Healthy Country gives off a greater vibration, and it speaks louder. Country that isn’t healthy also speaks and sings us there, and demands that we take action to heal it, its spirit and our spirit.” (Yamatji Noongar woman Heidi Mippy). Studies show that stronger relationships with Country and greater involvement in cultural practices enhance the well-being of Aboriginal and Torres Strait Islander people, and that individuals from more remote regions with daily access to and contact with their Country have higher levels of well-being than individuals that have been removed or relocated from traditional lands (Schultz et al 2018).

Indigenous seed collector assessing fruit maturity on Crotalaria cunninghamii, an important nitrogen-fixing pioneer shrub in post-mining ecological restoration in the northeast Kimberley region of Western Australia. Photo: Adam Guest.

Ecological degradation not only erodes biodiversity, compromises livelihoods, reduces ecosystem services, and impacts food security and cultural resilience, but also drives numerous environmental determinants of disease including allergies, anxiety disorders, immune dysfunction, infectious and zoonotic diseases, and mental health illnesses (Romanelli et al. 2015; Bhatnagar 2017; Burbank et al. 2017). European colonization has left a legacy of depression and cultural disconnection in farming communities throughout the above-mentioned Wheatbelt, which in turn has led to higher rates of suicide and chronic disease risk (Speldewinde et al. 2015).

The Nowanup Noongar Rangers often work on major restoration projects. Here they are planting a 300 metre totem animal, the Karda (Goanna), on land near Koi Kyeunu-ruff (the Stirling Ranges). Photo: Amanda Keesing.

These public health impacts of ecological degradation are straining health care systems and causing rising public health costs in Australia, and many places around the world. This in turn highlights the urgent need for a transition to a restorative culture (Cross et al. 2019; Blignaut & Aronson 2020), and recognition that ecological restoration, i.e., the repair of ecosystems that have been damaged, degraded or destroyed (Gann et al. 2019), should be recognized as an effective and cost-efficient public health intervention (Breed et al. 2020). Ecological restoration may be the best single strategy and toolbox for addressing climate change, biodiversity loss, and the poverty and misery related to ecological degradation and desertification. Ecological restoration and related activities, if undertaken in a participatory fashion, and through the pathways by which human well-being can be benefited by nature, may be effective in advancing health equity and addressing health disparities (Jelks et al 2021).

Ecological restoration is the only way by which landscapes degraded through activities such as mining (left) can be restored towards the biodiverse, ecologically functional ecosystems that were present prior to European colonisation (right), concurrently improving the physical, psychological, and cultural well-being of communities reliant upon these ecosystems.

Many of the nature exposure benefit pathways now suggested by “Western” science align well with Aboriginal and Torres Strait Islander lore and culture regarding ethnobotany, Traditional Ecological Knowledge (TEK), and how ecological and human health intersect. For example, potential pathways identified include exposure to environmental microbiota and plant-derived volatile organic compounds, the sight and sound-scape of nature, exposure to sunlight, and increased physical activity and social interaction (Marselle et al. 2021). For example, Noongar newborns were rubbed with plant-based oils to ensure strong and healthy development, aromatic leaves were crushed and inhaled or used to make infusions or ointments, the vapours of leaves and twigs of certain plants heated over coals were inhaled, and certain soils and animal fats were used both medicinally and in maintaining good health (Hansen and Horsfall 2018). Noongar People commonly use the environment around them to enhance physical, spiritual, social and emotional well-being, even recognising that different species play different roles in this relationship: “There are certain trees that we sit under when our spirit is down, we have to sit under that tree. We don’t cut that tree down, we don’t even take a branch off it. And they say when the needles fall on us from this tree… we’re told that’s the tears of our old people healing us. And when you hear the breeze whisper through that, that’s the old people singing to us, to heal us.” (Balladong Wadjuk Yorga/woman Vivienne Hansen).

Curtin University students being formally welcomed to a Nowanup camp by Noongar Elder Eugene Eades and the then Curtin Elder in Residence Professor Simon Forrest. Photo: Belinda Gibson.

Recent years have seen increasing incidence in landcare and ecological restoration activities led and undertaken by Aboriginal and Torres Strait Islander communities and organisations. Over 120 Indigenous Ranger Programs now operate Australia, drawing from deep cultural knowledge and connection to country to protect and manage terrestrial and also near-coastal and marine ecosystems. Ranger programs, and many other Indigenous-led and managed initiatives, are now involved in environmental management ranging from feral animal and weed control to fire management, and from native seed collection to landscape-scale ecological restoration activities. In many regions these programs, and the Aboriginal and Torres Strait Islander individuals who represent them, now lead the way and set the benchmark for sustainable and ecologically-responsible environmental management.

The re-introduction of more traditional management practices has happened rapidly in some areas. Across the ambitious Gondwana Link program in south-western Australia there are over a dozen First Nations ranger and land management teams, all of which have been established in the past fifteen years. One of these, the Ngadju Conservation Aboriginal Corporation, covers a massive 4.4 million hectares. Ngadju Conservation operate from a headquarters in the central town of Norseman, and undertake a wide range of cultural and ecological management efforts. Through agreement between the Traditional Owners of the land and the Commonwealth Government 78 dedicated Indigenous Protected Areas (IPA), covering over 74 million hectares, have been established since 1997. In these the national government provides funding to assist with land management, as set out in an agreed plan. The Ngadju IPA was formally designated in March 2021.

In Gondwana Link’s central zone, where marginal farmland is being purchased and restored ecologically, Noongar people have been welcomed back to the properties. On one of these, called Nowanup, the Noongar and settler community work together to maintain ecologically important habitats and replanted areas, as well as undertaking an ongoing series of cultural courses and camps. Since 2006 some 17,000 people have been through these camps, ranging from Noongar men at risk through to member of local community groups, school students from near and far and, more recently, groups of University students.

In recognition of the growing and leading role played by Aboriginal and Torres Strait Islander people in the restoration of Australia’s degraded landscapes, major national initiatives have been proposed seeking to support Indigenous-led environmental management. One such initiative is a newly-funded research centre to be established at Western Australia’s Curtin University, which will fuse Indigenous knowledge and traditional approaches with western science to rehabilitate and restore Country. This centre, the Australian Research Council Training Centre for Healing Country, aims to develop an economy centred around Indigenous-led ecological restoration activities; an economy built from a foundation of healthy Country intended to deliver both environmental outcomes and economic opportunity by developing Indigenous land management and restoration businesses into major regional employers.

The ARC Training Centre for Healing Country aims to establish strong, complementary and intersectional research pathways in ecological restoration (practices to repair degraded landscapes), ecohealth (understanding the intersection between ecological restoration and human health), and socioeconomics (examining how ecological restoration benefits livelihoods and social-cultural resilience). The aim is to bring Indigenous knowledge and traditional approaches together with western science and create better and more diverse pathways for the training of Indigenous peoples in environmental management and ecological restoration activities. In addition, Indigenous enterprises can be strengthened, grown, and empowered, and a diversified and Indigenous-led restoration economy can be a pathway along which we all work together towards a future of healthy Country and healthier multi-cultural society in Australia.

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Translocating a threatened totem: The impacts of mining on a culturally-significant species

Holly Bradley, Bill Bateman, and Adam Cross (Curtin University) describe the natural history and conservation of the Western Spiny-tailed Skink, an Australian lizard with a mixed history of translocation success. For more information, read their 2020 review on migration translocations in Conservation Biology.

Australia harbors approximately 10% of the Earth’s reptile species, and over 96% of all lizards and snakes occurring there are found nowhere else in the world. However, this incredible and irreplaceable biodiversity is under threat. Australia is one of the highest contributors to species losses globally, with over 1700 species and ecological communities threatened with extinction. In the last 20 years alone the number of threatened reptiles has nearly doubled, with 61 species now federally listed.

The Western Spiny-tailed Skink (Egernia stokesii badia) is just one example of a unique, endemic reptile threatened with extinction in Australia. Continued habitat degradation from practices such as grazing and mineral extraction (largely iron ore) are some of the major contributors to population decline.

The Western Spiny-tailed Skink (Egernia stokesii badia), an endangered Australian reptile threatened by habitat loss and disturbance from mining and farming activities. Photo: Holly Bradley

Western Spiny-tailed Skinks are one of the most social of all snake and lizard species – an uncommon trait among reptiles. Colonies of the skinks reside together in log ‘castles’, consisting of hollow logs and fallen branches. These natural structures provide a year-round residence for the skinks, who create latrine piles in select areas outside of the logs in order to keep the hollows clean.

Cultural significance

As well as being an ecologically unique threatened subspecies, with distinct spined scales particularly on their tails, and occurring only in a small region of Western Australia, spiny-tailed skinks are also culturally significant. PhD researcher Holly Bradley met with Badimia elder Darryl Fogarty to discuss the cultural significance of the skinks in her study area, the southern region of the Mid West. Elder Darryl Fogarty informed the local name of the skinks to be meelyu, and for some members of the regional community they represent a sacred totem. Totemic animals are common for many Indigenous groups across Australia and are linked with the worldview that people are an integral part of nature, belonging to a network of spiritual and physical entities.

Often, a totem will represent one’s connection with one’s nation, clan or family group. With a preordained totem comes a spiritual responsibility, where a person is accountable for the stewardship of their totem, meaning it is protected and passed down to the next generation. For many groups, this means that a person cannot eat the animal totem. Before Europeans colonized Australia, this traditional practice contributed to maintaining biodiversity and ensuring an abundance of food supplies; part of ‘caring for country,’ or maintaining ecosystem health.

The reverence with which totemic species were regarded helped to prevent significant declines in certain animal population numbers in the past. However, after the imposition of European land management into Western Australia, changes have occurred to the ecosystem balance. For example, large areas of native vegetation have been cleared, largely for urban development and agriculture, and the introduction of hoofed livestock has degraded and compacted soils. Introduction of domestic animals has also led to feral cat invasion across over 99.8% of the Australian land mass, which has led to wildlife devastation. For the skink, these changes have meant significant population declines throughout its Mid West range.

Example of in-tact open Eucalypt woodland (skink habitat) at risk of continued degradation from grazing and mining practices in the Mid West region of Western Australia. Photo: Holly Bradley.

Translocation requirements

In the face of continued transformation, habitat loss, and landscape-scale degradation, one of the ways in which Australia is trying to combat biodiversity loss is by relocating wildlife away from areas where they are likely to be (or definitely will be) impacted by these threats. Under Commonwealth regulation, if a proposed action by a mining company, such clearing of native vegetation, causes significant impact to a threatened species, approval may be conditional upon mitigation or offset measures, such as the translocation of individuals away from the threat. However, translocation is rarely a condition included as part of a decision notice without a high degree of certainty of success.

For non-threatened species, there are no Commonwealth laws which require a standard for translocations, and decisions are made on an ad hoc basis, generally with assisted relocation of larger charismatic mammals such as kangaroos and quenda, allowing local cities or councils a social license to continue urban development, without providing ongoing funding to monitor the long-term success of these translocations. After analyzing the outcomes of hundreds of translocation efforts around the world, we (Bradley et al. 2020) urge all land managers to shift their thinking away from what appears to be a poorly effective strategy. Although removing animals from areas destined for clearing might appear a simple resolution to the threats posed by activities such as urban sprawl or mining, it does not actually guarantee the survival of the individuals that are ‘saved’.  In fact, our review of this practice indicates that there is little follow-up on the success of translocation and many translocations may result in the eventual death of the translocated individuals.

To be successful, translocations need to ensure not only that relocated individuals survive but also that they contribute to the long-term persistence of a self-sustaining, reproducing population. Many mitigation-motivated translocations, i.e., relocations that respond to an immediate threat to individuals, have only the single goal of moving an individual or population away from the immediate danger. However, for these animals to actually survive and persist, it is critical that the design of translocation efforts be informed by sound science and an understanding of the complex ecology of the different species targeted for “saving”. Crucially, it is essential to monitor the translocated animals to understand their behaviour in the new location, estimate likely population viability in that location, and better understand and communicate how translocation efforts might be improved in the future.

We have just entered the United Nations Decade on Ecosystem Restoration, which represents a growing global commitment towards preventing, halting and reversing the degradation of ecosystems. However, for there to be the restoration and protection of fully functioning, healthy ecosystems, it is important for translocations to target a suite of ecologically significant species, rather than just the larger, charismatic mammals. Current biases generally exclude consideration of reptiles within assessments of mine site restoration success, despite their particularly high diversity and abundance within the arid mining regions of Australia, and their occupation of important ecological niches. The well-known ‘Field of Dreams’ idea, presented as one of the abiding myths of restoration ecology, assumes native animals will return on their own after revegetation of a site but, in practice, it doesn’t always work out that way.

Example of a naturally occurring log pile surrounded by everlastings (Rhodanthe collina) and red soil typical of the Mid West region of Western Australia. Log piles typically consist of a single fallen Eucalyptus tree log, overlapped by a number of branches. Photo: Holly Bradley.

Translocation case study: spiny-tailed skinks

As iron ore extraction continues in Western Spiny-tailed Skink’s habitat throughout the Mid West region, future translocations of colonies of this endangered reptile are likely. Understanding the basic requirements for establishment and persistence is crucial, and gathering this knowledge requires significant investment in research and monitoring. For example, detailed studies are required of the diet and habitat log pile characteristics needed for colonies to thrive. As these skinks are shy and observational records are difficult to obtain, this means other research methods are required, such as collecting scats for visual and genetic analysis of the invertebrate and plant contents of their diet. A more informed understanding of diet can help improve translocation site selection, as it is important to know what plant and animal species are important food sources that must be present or else be planted or reintroduced in restoration sites for successful recolonization.

An adult and juvenile spiny-tailed skink (Egernia stokesii badia) sharing a log pile as their permanent residence. Photo: Holly Bradley.

Another example of critical information to promote successful translocations is understanding the key predation threats to the Western Spiny-tailed Skink. Despite the protection of their unique spined tails which allow them to lodge tightly into crevices and act as a defensive mechanism against attack, they are still at risk of decline from predation. One method to understand the key predators of skinks within the Mid West has been to place camera traps at active colony sites. Below is an example of an image captured of a feral cat with an adult skink in its mouth, indicating that control of feral predators, particularly cats, is likely to be critical in ensuring the initial survival of relocated skink individuals.

Feral cat with an adult spiny-tailed skink within its mouth, at a log pile site within the Mid West. Footage captured using a motion-activated camera. Photo: Holly Bradley.

It is also important to understand how translocated individuals integrate within the recipient ecosystem, and that they do not introduce any non-native parasites, or outcompete any native species for food resources. Research by Bradley et al. (2020) shows that those who undertake mitigation translocations rarely consider the long-term impacts of how translocated animals affect the recipient ecosystem, and if the carrying capacity of the translocation site has space for the introduction of new individuals.

Translocation can be expensive (for example, the relocation of cheetahs (Acinonyx jubatus) in Namibia cost about $2800 USD per individual), and the continued funding and implementation of ad hoc species relocations to justify continued habitat loss may be both wrong-headed and a waste of limited conservation dollars. Translocation is also a highly stressful practice for the animals, and it is counter-productive to go through such efforts if there are no territories or food resources available for their survival.

To improve the outcome of future translocations of the Western Spiny-tailed Skink, it is also important to understand the complexity of the recipient ecosystem and how best to help translocated individuals assimilate there. Detailed habitat assessment and locating appropriate log pile structures can determine if the recipient site is appropriate for the skinks, and targeted surveys can determine if skinks are already present within the area. Selection of translocation sites as close as possible to the source location will prevent the co-introduction of non-native parasites or diseases.

An adult Western Spiny-tailed Skink sunbathing on a log pile. Photo: Holly Bradley

The way forward

Less than half of all published studies undertaking translocations compared or tested different techniques (Bradley et al. 2020). Without a comparison of different techniques, such as whether supplementary feeding during an ‘acclimation’ phase at the translocation site or if the establishment of temporary fencing might help population establishment compared with simply releasing animals into new habitat, it will be very difficult to improve translocation practices for the future. Given current success rates are less than 25% for mitigation translocations around the world (i.e., the number resulting in self-sustaining populations), there is huge room for improvement. A holistic approach to land management considering both ecological and cultural significance can both protect and restore community wellbeing, as well as promote the return of functional, self-sustaining ecosystems in restoration practice.

For more information, read our 2020 review of migration translocation success in Conservation Biology: Bradley H, Tomlinson S, Craig M, Cross AT, Bateman B. 2020. Mitigation translocation as a management tool. Conservation Biology https://doi.org/10.1111/cobi.13667.

Save me, Seymour! The increasingly dire plight of Darwin’s “Most wonderful plants in the world”

Adam Cross and Thilo Krueger describe the natural history and conservation of carnivorous plants. Adam is a research fellow at Curtin University , Western Australia and Science Director for the EcoHealth Network. Thilo is a masters student in Adam’s research group and is researching prey spectra and other plant-animal interactions of carnivorous plants.

Carnivorous plants are a unique and fascinating group that have captivated scientists and the public, as well as inspired writers and film makers, for well over a hundred years. During his seminal 1875 work Insectivorous Plants, while studying one of the sticky-leaved Sundews (Drosera), British naturalist Charles Darwin once famously and not at all exaggeratedly wrote “I care more about Drosera than the origin of all the species in the world”. These incredible species have flipped the traditional perception of plants as immobile producers, and possess highly modified leaves that have evolved to attract, capture and digest animal prey – mostly small insects, but for some species occasionally also birds and small mammals.

Drosera leioblastus (Droseraceae) is an example of a carnivorous plant species threatened by high-intensity or aseasonal fire events. An extreme bushfire north of Perth, Western Australia, in 2006 reduced the only known population at the time from several thousand individuals to eleven in 2008. As of 2020, just seven plants remain at this site. Photo: Thilo Krueger.

Capturing prey allows carnivorous plants to obtain nutrients in habitats where soils are extremely nutrient-poor, and they thrive in areas like swamps, rocky seepages and dripping rock walls, seasonally-flooded lowlands and even the canopies of tropical rainforests. Many species of these predatory plants grow in almost pure sand or in laterite soils, which are notoriously low in important nutrients for plants such as nitrogen and phosphorus. In these habitats, carnivory represents a very effective strategy for competition and survival.

A field of the stunning Sarracenia leucophylla growing in Long Leaf Pine savanna in Louisiana, USA – sadly, once-common sights like these are becoming increasingly rare as habitat continues to be lost. Photo: Adam Cross.

While there are several very well-known carnivorous plants, such as the Venus Flytrap (Dionaea) and Trumpet Pitcher Plants (Sarracenia) of North America, there are in fact over 860 species that are currently described world-wide. Incredibly, carnivory has independently evolved at least 11 times in different plant lineages, and at many different points in time. This evolutionary development has led to a wide diversity not only in the size and form or carnivorous plants, but also their function and biology. While some species are not much larger than a single grain of sand (such as the diminutive Utricularia simmonsii, one of the smallest of all flowering plants), the largest species are vines growing up to 60 m into rainforest canopies (Triphyophyllum peltatum). Many species are terrestrial, occurring in habitats ranging from mountain tops to Mediterranean scrubland to seasonally-wet swampland, and numerous species have become partially or even fully aquatic. Within tropical rainforests, there are even a number of epiphytic carnivorous plants – species growing high in the canopy on the mossy trunks or branches of trees.

The colourful and intricately veined pitchers of Sarracenia leucophylla, which apparently almost glow under moonlight and capture large numbers of night-flying moths. Photo: Adam Cross.

However, perhaps most incredibly, there are many different structures and methods that plants have evolved for carnivory. A range of genera, including Byblis (Byblidaceae), Drosera (Droseraceae), Drosophyllum (Drosophyllaceae), Pinguicula (Lentibulariaceae) and Triphyophyllum (Dioncophyllaceae) employ sticky leaves to capture prey, relying upon mucilage produced by specialized sessile or motile glands containing digestive enzymes to snare and absorb nutrients from insects. Philcoxia (Plantaginaceae) also produces sticky leaves, but holds these beneath the soil surface to capture small nematodes and other small subterranean fauna. Some species produce leaves modified to form pitchers of varying complexity with slippery walls to prevent the escape of captured prey, which drown and are digested in pools of water and enzymes (Brocchinia and Catopsis [Poaceae], Cephalotus [Cephalotaceae], Nepenthes [Nepenthaceae], and Darlingtonia, Heliamphora, Sarracenia [Sarraceniaceae]). Still others utilize quick-moving, snapping lobed traps (Dionaea and Aldrovanda [Droseraceae]), and many species even produce highly complex subterranean corkscrew and suction traps (Genlisea and Utricularia [Lentibulariaceae]). Some of these structures are capable of making among the fastest movements in the plant kingdom.

The critically endangered carnivorous plant Byblis gigantea (Byblidaceae) growing in a wetland near Perth, Western Australia. This species has suffered dramatic population declines in the last 30 years, losing approximately two thirds of all recorded subpopulations to urban development. Photo: Thilo Krueger.

A number of carnivorous plants also exhibit amazing biological mutualisms, being rather paradoxically reliant upon animals for their growth and survival. Roridula (Roridulaceae) produces sticky resin from glands on its leaves, but lacks the capability to produce any digestive enzymes and instead relies upon a unique digestive mutualism with a Hemipteran bug (Pameridea species) to absorb nutrients from captured prey, as these bugs can move among the resinous glands without being captured and defecate onto the leaf surface. Similar digestive mutualisms are known for Hemipteran bugs of the genus Setocoris with Byblis and some species of Drosera. The digestive fluid of the pitcher plant Cephalotus follicularis provides crucial breeding habitat for a species of stiltfly (Badisis ambulans), while Nepenthes hemsleyana provides a safe roosting site for Hardwicke’s bat and in return benefits from digesting the ablutions of roosting bats in addition to capturing insect prey. Other Nepenthes, such as the Bornean N. lowii, produce an appealing food for tree shrews on the underside of the pitcher lid, which has a laxative effect and results in the shrew depositing a package of nutrients into the pitcher ‘latrine’ in return for the feed. It has even been proposed that the squat pitchers of Nepenthes ampullaria, which are open to the rain and catch falling leaf detritus, could be vegetarian.

Nepenthes albomarginata growing in Malaysia. Photo: Thilo Krueger.

These predatory plants can be found on every continent except Antarctica, but there are distinct “hotspots” of carnivorous plant diversity in South America, South Africa, Southeast Asia and Australia. Almost a quarter of all currently described carnivorous plants can be found in the ancient, nutrient-poor landscapes of Western Australia, for example. Unfortunately, many of these areas are also experiencing some of the world’s highest rates of habitat destruction – in the southwest of Western Australia, where approximately 120 species of carnivorous plants occur, approximately 70% of all native vegetation (and up to 97% in some regions) has been cleared for agriculture and urban development. What little native vegetation remains is often isolated, heavily fragmented, and significantly degraded from weed invasion and poor fire management.

Carnivorous plants have been described as harbingers of ecosystem integrity, as they are often the first to disappear after disturbance. As might be expected given their unique ecologies, most carnivorous plants have very small ecological niches and are extremely sensitive to environmental change. Given that they often rely on habitats such as nutrient-poor wetlands, which are particularly vulnerable to human impacts and represent some of the most threatened ecosystems globally, carnivorous plants face an existential threat in the 21st Century.

The summit of Mt Roraima, a tepui in Venezuela, isolated from the surrounding savanna by 800 m high cliffs and harbouring numerous species of carnivorous plants including species of the unique Sun Pitchers (Heliamphora). Photo: Adam Cross.

A recent international study by Cross et al. (2020) examining the conservation status and threats faced by carnivorous plants found approximately a quarter of all species around the world were at risk of extinction. The highest numbers of critically endangered species occurred in Australia, Brazil, Indonesia, Philippines, Cuba and Thailand – in many cases, the same areas regarded as the most significant hotspots of carnivorous plant diversity. Importantly, 89 species of carnivorous plants (over 10% of all species) are only known from a single location, making them particularly vulnerable to any disturbances, and particularly rapid impacts, to their habitats.

Nepenthes fusca, a tropical pitcher plant, growing in a dense peat-swamp forest remnant in Malaysian Borneo. Photo: Adam Cross.

Due to their unique insect-capturing traits and often spectacular appearance, many carnivorous plants are very popular with horticulturists and hobby plant collectors. Unfortunately, this has created a significant market for illegal collection – also known as poaching – of carnivorous plants and several species have already been driven to the brink of extinction by poachers. Pitcher Plants such as Tropical Pitcher Plants from south-east Asia and the Albany Pitcher Plant from Western Australia are particularly affected by poaching but even the iconic Venus Flytrap from the United States continues to be plagued by unscrupulous poachers. There must be immediate and concerted global action to cease the illegal collection of wild plants, and much greater regulatory enforcement of biodiversity protection laws to end carnivorous plant poaching.

The snapping traps of the Venus Flytrap, Dionaea muscipula, on individuals growing in open wet savanna at one of the increasingly few remnant populations of this iconic species in North Carolina, USA.

Cross et al. found that the continuing clearing of natural vegetation for agriculture, urban development and mining projects represented by far the most severe and immediate threat to carnivorous plants. In just the past two decades, massive areas of pristine habitat have been converted into oil palm plantations in Southeast Asia, cattle farms in Brazil, or suburban housing and industrial development in Australia. For example, two of the last remaining populations of the Critically Endangered rainbow plant (Byblis gigantea) in Perth, Western Australia, were destroyed for the construction of a liquor supermarket and a logistics distribution centre. Several populations of sundews (Drosera) near the town of Hermanus, in South Africa, are rather paradoxically being lost to the development of a settlement known as “Sundew Villas”. Much stronger protections are required to ensure that remnant carnivorous plant habitats are protected and conserved.

One of the World’s rarest carnivorous plant species, Drosera oreopodion, from Perth, Western Australia. This critically endangered species is known from only a few hundred plants in an area just a few square metres in size. The population is situated in a narrow and unmanaged railway reserve, threatened by weed infestation, disturbance and fire events. Its population count continues to shrink, and one fire or clearing event would likely cause immediate extinction. Photo: Thilo Krueger.

Climate change poses another significant threat to carnivorous plants, especially the many species occurring in Mediterranean climate regions where warming, drying trends are already becoming evident. Extreme and prolonged drought conditions, such as have been recently experienced in many Mediterranean climate regions around the world, can not only impact directly upon species and communities, they can also fuel high-intensity and aseasonal fires. Although fire forms a natural part of the ecology of many ecosystems in which carnivorous plants occur, fire regimes have been increasingly altered by climate change and inadequate fire management practices. The effect of altered fire regimes on carnivorous plants is complex, idiosyncratic and often still poorly understood; while some species (especially geophytes such as tuberous Drosera) may benefit from high-intensity fires that remove competition from other vegetation, the same fire can have devastating impacts on other species lacking underground structures for resprouting. For example, an extreme summer bushfire in 2006 near Perth, Western Australia, fuelled by record drought conditions at the time, reduced the only known population of the critically endangered Drosera leioblastus from several thousand individuals to just 11 plants, while simultaneously inducing mass-flowering of most tuberous Drosera in the same area. The complex effect of fire and the need for sound fire management policies is highlighted by the Albany Pitcher Plant (Cephalotus follicularis), which is threatened both by prescribed burning at short fire intervals as well as long-term fire suppression. Weed invasion can further exacerbate fire management, and Cross et al. (2020) suggest that simultaneous prioritisation should be afforded to invasive species management and the maintenance and preservation of natural ecosystem processes such as fire regimes and hydrological functioning.

The iconic Cephalotus follicularis (Albany Pitcher Plant; Cephalotaceae) from south-west Western Australia produces highly modified cup-shaped leaves filled with a mixture of water and digestive enzymes. Prey is captured by falling into the trap (which features slippery walls and inward pointing “teeth” to prevent escape). After drowning in the digestive fluid, the plant will absorb the prey’s important nutrients such as nitrogen and phosphorus. Photo: Thilo Krueger.

Ecological restoration offers not only hope for the return of many carnivorous plant species to regions from which they have been lost, but also an effective mechanism by which ecosystem functioning and natural processes like fire and hydrology can be reinstated in degraded landscapes where these processes have been impaired. While there is growing urgency to conserve what little natural carnivorous plant habitat remains, Cross et al. (2020) highlight the growing imperative to begin scaling up restoration efforts in areas where habitat loss and ecosystem disturbance have been most severe, in order to concomitantly provide new habitat for these species and provide buffers for protected areas. Far too often remnant habitats are not only highly fragmented but also abut farmland or urban developments, and the restoration of ecological corridors and buffer zones will confer resilience and greater ecological integrity to these increasingly beleaguered ecosystems.

The loss of carnivorous plants would not only be a devastating loss for future generations, but could potentially have detrimental effects across ecosystems. They have captivated scientists and the public for hundreds of years, from their portrayal as horrifying monsters in popular films to providing inspiration for the development of non-stick surfaces. But they are integral parts of ecosystems, important cogs in the complex biodiverse systems in which we live and upon which we rely, and we must preserve them. The number of vulnerable, endangered and extinct species continues to grow despite conservation efforts around the world, and it is clear that we must begin investing significantly in the restoration of carnivorous plant habitats, particularly in regions such as Australia, Brazil, South Africa, southeast Asia and North America, if they are to survive for future generations to marvel at.

Sarracenia flava growing in Florida, USA. Photo: Thilo Krueger.

Our global review of the conservation status of carnivorous plants can be read in full, open access, here. To learn more about the unique and incredible biology of our carnivorous plant heritage, see a recent international monograph about their ecology, biology and evolution to which the present authors were contributors. The authors have also recently written books on some of the most amazing carnivorous plant species, including the Waterwheel Plant, Aldrovanda vesiculosa and the Albany Pitcher Plant, Cephalotus follicularis.

Healthy Societies built from Healthy Ecosystems: How Australia and Aotearoa New Zealand are Working at the Intersection of Human Health and Ecological Restoration for a Healthier World

Adam Cross (Curtin University), Kiri Wallace (University of Waikato), and James Aronson (Missouri Botanical Garden) discuss the newly formed Four Islands EcoHealth Network, a regional coalition allied with the global action initiative EcoHealth Network, which aims to increase the amount and effectiveness of ecological restoration throughout the world. The new papers they discuss are published in the journals EcoHealth and Restoration Ecology.

We live in an age of environmental challenges and crises that require societies to sit up and pay more attention to how they function. From heatwaves and water shortages to megafires and sudden floods (sometimes one after the other), new virulent viruses and infectious diseases, salinization where it doesn’t ‘belong’, plastic pollution in our oceans (where it really doesn’t belong), climate change and compromised food and job security for hundreds of millions of people, the combined impact of these challenges on human life are significant, to say the least.

While low-intensity seasonal or episodic fires are a natural part of the ecology in many regions of Australia such as the Kimberley (top left, photo A. Cross), intense, aseasonal or too-frequent fires can be devastating to ecosystems such as kwongan heathland (top right, photo A. Keesing) or seasonal peat wetlands (bottom; photo D. Edmonds).

The ecological and economic impacts of the environmental disaster known as climate change have resulted in thousands of jurisdictions in dozens of countries declaring a climate emergency, including many in Australia and Aotearoa New Zealand. Both countries are predicted to experience a hotter, drier climate in the coming years, a trend already showing itself through ominous impacts on forests and other ecosystems on land and at sea, including the oceans on Australia’s eastern coasts, where coral reefs and kelp forests are showing clear early signs of collapse. In both Australia and New Zealand, aseasonal or large-scale fires appear to be pushing some endangered species towards extinction and vital habitats and ecosystems to the brink. During the Australian summer of 2019-2020, unusually intense wildfires burnt an estimated 18.6 million hectares (46 million acres) across Australia and left ecosystems and communities reeling: the fires killed 34 and destroyed approximately 3,000 homes, and are estimated to have killed over a billion native animals.

Australia’s exceptional biodiversity includes many unique species, such as the Thorny Devil (Moloch horridus; Left), Emu (Dromaius novaehollandiae, Center), and Echidna (Tachyglossus aculeatus; Right). All photos Sophie Cross.

These fires and their aftermath have created a flashpoint where conflicting responses to climate change and its effects are emerging in sharp relief. Strong social divisions have long existed over expanding gas, oil, and coal mining projects in mainland Australia and Tasmania, all of which of course contribute massively to anthropogenic climate change. Debate and conflict over logging in the remaining natural forests has also intensified. The degradation of ecosystems can also cause significant public health impacts. Studies have linked high rates of depression and even suicides in farming communities to the stresses of drought and fire. The fragmentation and clearing of forests for timber and unsustainable agricultural practices has isolated and displaced Indigenous Peoples and communities, leading to conflict, loss of cultural identity, and damage to livelihoods, and has contributed to a rise in zoonotic (animal-transmitted) diseases such as the catastrophic and ongoing effects of Covid-19. Smoke from the recent Australian bushfires reduced air quality to dangerous levels in cities around Australia, potentially killing 12-times more people than the flames did, and the smoke plume travelled over 11,000 km across the Pacific Ocean to South America.

Time for Deep Change

In support of the upcoming UN Decade on Ecosystem Restoration (to run from 2021–2030, concurrently with a Decade on Ocean Science for Sustainable Development), two recent articles by Breed et al. and Aronson et al. bring new weight to the argument that ecological restoration is one of the most promising strategies we have to stop and reverse our current trajectory of environmental chaos. Indeed, Breed and colleagues suggest that the human health benefits of undertaking and engaging in ecological restoration might be so significant that restoration could be considered an economically and politically effective large-scale public health intervention. These benefits might be at the scale of the individual, resulting from direct participation in restoration activities (e.g., the act of working together on restoring an area can reduce anxiety and depression-related diseases). Or, they might be at the population and community levels, resulting from the indirect outcomes of ecological restoration (e.g., restored ecosystems and reintegrated landscapes provide cleaner water, and more health-promoting microbiomes, reducing a number of disease risks).

Restoration projects, such as the Arbor Day planting events of People, Cities & Nature, at Waiwhakareke Natural Heritage Park in Hamilton, New Zealand, can bring community together and may have significant public health benefits for participants. All photos C. Kirby.

Breed and colleagues proposed five key strategies to help us better understand the potential of ecological restoration as a public health initiative:

  1. Collaborations and conversations. Promoting greater collaboration among scientists of various disciplines, health professionals, restoration practitioners, and policymakers to better understand the links between ecological restoration and human health and wellbeing (including jobs and livelihoods).  
  2. Education and learning. Restorationists need to learn about human health, and health professionals must in turn learn about the real potential of ecological restoration as a public health intervention.
  3. Defining the causal links. Research is needed to determine the causal links between ecosystem restoration and health outcomes, to provide the empirical evidence required to understand and advise communities and decision makers.
  4. Monitoring restoration and health outcomes. We need better and standardized methodologies for the effective, cost-efficient monitoring and evaluation of the public health benefits from ecosystem restoration.
  5. Community ownership and stewardship. A global movement toward a restorative culture needs community involvement and engagement, and embracing of the importance of traditional ecological knowledge.

Putting these strategies into action at a scale required to meet the aspirations of the coming UN Decade means we must collaborate across continents and disciplines to identify and build links between ecological restoration and human health.

One such initiative is the Ecohealth Network (EHN), established in 2017 to bring together pioneering sites, hubs, and regional networks to work cohesively towards rapidly increasing the amount and effectiveness of ecological restoration throughout the world, and to accelerate understanding and awareness of its feasibility and benefits, especially for public health.

The first EHN regional network emerged from a workshop held in February 2020. The group calls itself the Four Islands EcoHealth Network, in reference to North Island and South Island, the two largest islands of Aotearoa New Zealand, plus Tasmania, and mainland Australia. It aims to explore how different sites and hubs with various climatic and cultural contexts can come together to share insights and pursue research into the physiological, psychological, and societal health benefits of ecological restoration. It also aims to advance the ecological and microbiological knowledge needed to achieve effective, durable restoration. The aspirations, aims and issues to be considered by the group were laid out in the Hobart Declaration, a charter document stemming from the workshop. Keith Bradby, the founder and CEO of Gondwana Link, agreed to be the first coordinator of the regional network.

The Four Islands EcoHealth Network also embodies a shared desire to foster support for long-overdue efforts in both countries that work in close collaboration with Indigenous Peoples and local communities to make radical changes in cultural, educational, and land care practices. A recent popular science article by Dr. Kiri Joy Wallace highlighted the significance of these aspirations to the public health sector, native ecosystems, and people of Aotearoa New Zealand. There are also many Australian contexts bringing insight and direction to the initiative. For example, Gondwana Link is working to restore ecological resilience to thousands of hectares of marginal farmland following long colonial histories of Neo-European style agricultural use and severe salinization in southwestern Australia; Gondwana Link is exemplary in its huge regional scope and sustained work for greater interaction and cooperation not only with local conservation groups, but also with Noongar and Ngadju Traditional Owners. This effort, based on a vision shared by all members of the EHN, is part of the essential process of “decolonizing” both conservation and ecological restoration.

Other members of the Four Islands EcoHealth Network tackle the restoration and assisted recovery of wilderness areas in north-eastern Tasmania following industrial tree cropping with Monterrey pine (Pinus radiata), undertaken with great success by the North East Bioregional Network; vast regional, multi-state initiatives such as the Great Eastern Ranges work to conserve and reconnect habitat at large scales; and science-led and community-focussed programs such as the UN-endorsed Healthy Urban Microbiome Initiative, which explores the human health benefits of biodiverse green space in urban areas via the microbiome and smaller local studies examining the mental health benefits of urban schoolchildren participating in restorative activities.

These experiences in the Four Islands context, and the insights and expertise of its founding members, are helping to anchor and inform efforts by the wider EcoHealth Network to link similarly ambitious initiatives in other regions and build a broad global network stretching across the globe.

Restoration can and must underpin every aspect of human society, as our health and welfare, and those of future generations, are dependent on the ecosystems of which we are part. If we are to achieve the aspirations of the coming UN Decade on Ecosystem Restoration, we need to work towards a culture of healing and renewal to replace the damaging models of colonialism, systemic injustice, unrestrained resource extraction, and ecological destruction. The accelerating climate catastrophe and the Covid-19 pandemic have profoundly impacted people’s lives in every nation, increasing awareness about the direct link between human health and the environment. We need to ensure this catalyzes a shift to a restorative culture globally, toward what we can only hope will one day be a world of truly united nations.

To learn more about the Ecohealth Network or the work of the members of the Four Islands Ecohealth Network, visit our website or read our recent papers in EcoHealth and Restoration Ecology.

Post-Mine restoration, the Gondwana Link, and SER Australasia – helping Australia transition towards a restoration culture

In their fourth and last report from arid Australia, James and Thibaud Aronson discuss promising approaches and programs squarely facing the conservation issues that threaten western Australian ecosystems.

Nothing is simple these days: everything is subject to trade-offs. For example, take Australia’s mining industry. The country has long drawn on its enormous mineral wealth, which sustains a significant part of its economic growth. But this takes a huge toll on biodiversity. Kingsley Dixon, with whom we spent a week in the field, helped us understand the situation, and noted that the miners do not have a very good track record of cleaning up after themselves. Today, there are around 50,000 abandoned mines in Australia – sad testimony to the boom and bust pattern that seems to characterize all too many extractive industries everywhere.  However, the pioneering work of Kingsley and his colleagues and students, in the areas of seed science, conservation biology, and restoration ecology, is helping advance the science and technology of restoration. This is difficult business under any circumstances, but especially so in a biodiversity hotspot. He is also extremely active in trying to persuade the mining industry and Australian government to do more and do it better in these areas.

Dr. Kingsley Dixon with a Eucalyptus leucophloia. Pilbara region, Western Australia.

Dr. Kingsley Dixon with a Eucalyptus leucophloia. Pilbara region, Western Australia.

The Mt Whaleback mine has been producing iron ore for nearly fifty years. The pit is half a kilometer deep and 5 kilometers long, and growing. Kingsley Dixon and his team are now involved in a project to restore parts of the site.

The Mt Whaleback mine, in Western Australia, has been producing iron ore for nearly fifty years. The pit is half a kilometer deep and 5 kilometers long, and growing. Kingsley Dixon and his team are now involved in a project to restore parts of the site.

This photo, taken on the other side of the mine, shows the first step of restoration. This involves reshaping the slopes, from the steep ones seen on the right, to gentler ones on the left, which are suitable for planting. This has already cost 1 million dollars.

This photo, taken on the other side of the mine, shows the first step of restoration. This involves reshaping the slopes, from the steep ones seen on the right, to gentler ones on the left, which are suitable for planting. This has already cost 1 million dollars. (And, make no mistake, just about every plant growing on the slopes on the right are exotic invasives.)

Happily, despite the complexity and the obstacles, a few Australian conservation organizations are also engaged in ecological restoration – whether at the site level, or much broader scales.

Many people told us that Australians are truly proud of their unique natural heritage, and the “outback”; it only remains for the government to play a larger role, and support those who are already working towards sustainability and a restoration culture.

One of the largest players is the Australian Wildlife Conservancy (AWC), linked in a small way to the US-based organization, The Nature Conservancy (TNC). The AWC is making significant investments not only in land acquisition for conservation but also conservation research and outreach to the public.

Another example of an outstanding initiative is the 13-year old Gondwana Link, a unique and inspiring venture in the southwest. Indeed, they aim to create a biodiversity corridor 1000 km long, spanning 8 different ecosystem types. We spent several days with Keith Bradby, Chief Executive Officer of Gondwana Link, as well as Mike Griffiths, recently posted to Kalgoorlie, and veteran consultant and restoration practitioner US- born Justin Jonson, learning about the wonderfully exciting work of this coalition. They work both by acquiring pristine fragments, as well as degraded land which they restore, to provide connections between patches of habitat protected in national parks. But even more than their goals, it is their approach that is unique. Instead of coming in and telling everyone who isn’t a conservationist they they’re wrong and evil, they work with the miners, and the farmers, and the various NGOS, to achieve a vision of the landscape where humans and biodiversity can co-exist. For more information, see the chapter on Gondwana Link in Paddy Woodworth’s book Our Once and Future Planet , the first book to present the world-wide scene of ecological restoration to the general public.

The gorgeous Great Western Woodlands, near Norseman, Western Australia.

The gorgeous Great Western Woodlands, near Norseman, Western Australia.

They also have a strong commitment to work with Aboriginal Traditional Owners, of both the Ngadju and Noongar peoples. Aboriginal Australians represent only 3% of the national population of 24,000,000, but finally, and bit by bit, justice is being done. Following the 1993 Native Title Act, and 18 years of shameful litigation, Aboriginal Australians are at last being granted “native title” in their own land, and control a growing percentage of Australian outback. On these recovered lands, some communities are trying to reconcile their truly ancient traditions with sound ecological management appropriate to the new lifestyles they have taken up, and the future they desire for themselves.

Another remarkable actor is the 400 – strong Australasian chapter of the Society for Ecological Restoration (SERA), led by its chair Kingsley Dixon. The challenges they face are daunting, but important and encouraging steps forward are being taken and the network is successfully raising money and doing projects. If one’s government is not helping, after all – as is the case with the current administration in Australia, social networks – of people and institutions – are the key. As we noted in our blogpost from Jordan, last April, another source of hope is the Ecological Restoration Alliance of Botanic Gardens.

To conclude, as Paul Hawken notes in Blessed Unrest,

If you look at the science that describes what is happening on earth today and aren’t pessimistic, you don’t have the correct data. If you meet people in this unnamed movement and aren’t optimistic, you haven’t got a heart.

What unnamed movement? He was referring to the thousands of independent non-governmental groups of people working for joint environmental and social change – not one or the other, but both.

As we discovered, in Australia there are plenty of clear-eyed people in conservation and restoration who do have a heart and who are working for what we would call a restoration culture for the 21st century. There: that’s a name then for the unnamed movement of this century that Hawkins referred to.

Australia’s amazing and vulnerable deserts – not as pristine as they look.

In this second report from arid Australia, James and Thibaud Aronson discuss the debated roles of fire, cattle and invasive mammals on the native fauna and flora.

To quote Gary Dinham, director of the Alice Springs Desert Park, “although the average annual rainfall in Alice Springs is just 270 mm, [9 in.], it’s erratic. For example, in 2009 the year’s total rainfall at Desert Park was 64 mm. In 2010, it was 990!”

Imagine, then, a vast region where almost no rain falls for several years, and then one year, a meter falls in two weeks, causing devastating floods. Despite the aridity, and the unpredictability, there are wooded areas in vast parts of inland Australia with annual rainfall comparable to that of Syria or Sudan! In fact,  there is such a remarkable diversity of trees and shrubs, and indeed such extensive savanna or woodland tree cover, that it makes perfect sense to speak of desert canopies occurring there. However, that stunning first impression does not reveal how much the ecosystems and landscapes have been disturbed, especially in the past two centuries. How? Through severely altered fire regimes, overgrazing by domestic and feral herbivores, open-pit mining, and outrageous numbers of intentional and accidental introductions of exotic species of all sorts that really shouldn’t be there.

Open Eucalypt woodland with spinifex grass (Triodia spp.) dominated undergrowth. Karijini National Park, Western Australia.

Open Eucalypt woodland with spinifex grass (Triodia spp.) dominated undergrowth. Karijini National Park, Western Australia.

Because of its inordinately high biomass, the Australian center burns – or gets burned – every year or every other year…. The 70 species of spinifex grasses present throughout the arid and semiarid areas are in fact some of the most flammable plants on the planet. But that’s just part of the story.

500 meters away from where the previous photo was taken, this spot had burned six months earlier. The Eucalypts display here  the unusual feature of branches resprouting high in a tree with a completely burnt trunk. What makes this possible in some trees – including the Mediterranean cork oak - is epicormic buds. Annuals are taking advantage of the nutrients released in the soil, and the spinifex will come back too, only that will take a little longer.

500 meters away from where the previous photo was taken, this spot had burned six months earlier. The Eucalypts display here the unusual feature of branches resprouting high in a tree with a completely burnt trunk. What makes this possible in some few trees – including the Mediterranean cork oak – is epicormic buds. Taking advantage of the pulse of nutrients released in the soil, annuals have germinated in profusion, and spinifex will come back too, a little slower.

Because European settlers stubbornly tried to import inappropriate farming and pastoral techniques into Australia’s arid center, with its poor soils and unpredictable rainfall, they overstocked and let their cattle roam essentially freely over vast areas. Under these conditions, certain grasses and shrubs are favored, and vegetation is much more fire-prone. this has led to a large increase in the frequency of monster fires, capable of burning vast areas within days or weeks.

Even today, most landowners with cattle in the outback burn their land every single year. Why? So as to reduce fuel load, as a matter of fact, in efforts – often unsuccessful, as we’ve just said – to reduce the risk of wildfires that might burn down their houses and other infrastructure. But they also are aiming to increase the amount of palatable grasses, including the introduced Buffel grass.

Buffel grass (Cenchrus ciliaris) by a river, showing the worst of its invasive capability, where it forms a blanket which crowns out all other understorey species under the canopy of red river gums (Euc. camaldulensis).

Buffel grass (Pennisetum cenchroides, more commonly known by its old name Cenchrus ciliaris) by a river, showing the worst of its invasive capability, crowding out all native understory species under the canopy of red river gums (Euc. camaldulensis). Hardey River, near Paraburdoo, Western Australia.

There is little doubt that this approach could be improved on, but the truly problematic point is whether or not the desert needs to burn. That debate ultimately is rooted in divergent interpretations of the past 100,000 years of Australia’s history.

It is generally agreed that humans arrived on the island continent approximately 50,000 years ago. What is unclear is what lasting impact the first immigrants had, and on what scale. The suggested date for their arrival roughly coincides with the extinction of all animal species weighing more than 100 kg, similar to what happened later in the Americas and even later in Madagascar. Therefore, some argue that humans must have driven the megafauna to extinction. Others say that Australia had been getting progressively hotter and drier for 20 to 50 thousand years prior to the arrival of humans, and that large animals could not cope with the new climate. If that’s true, at most the earliest Australians hunted out only tiny remnant populations of these large animals (including giant kangaroos, rhinoceros-sized wombats, a lizard twice the size of a Komodo dragon, giant turtles, marsupial lions, and some of the largest birds that ever lived on Earth).

Beaten only by the ostrich, the emu (Dromaius novaehollandiae) is the second largest living bird, standing as tall as an average person. Among the now extinct Australian megafauna was the flightless mihurung or thunder bird (Dromornis stirtoni), that was nearly twice the size of an emu and weighed half a ton!

Beaten only by the ostrich, the emu (Dromaius novaehollandiae) is the second largest living bird, standing as tall as an average person. However, it is small compared to the now extinct mihurung or thunder bird (Dromornis stirtoni), that was nearly twice its size and weighed half a ton!

Through the use of ‘fire-stick farming’ (the practice of setting fires in patches to stimulate new tender shoots on grasses and other plants, and thereby attract game), the Aborigines – according to some scholars – gradually transformed most of Australia’s landscapes from fire-sensitive thickets, woodlands, and forests, to spinifex grasslands and Eucalypt woodlands highly tolerant of this kind of fire regime.

Others counter that the earliest humans in Australia in fact stayed at low population densities until the arrival of Europeans and that their nomadic societies could not possibly have transformed landscapes at any meaningful scale. To date, no clear consensus has yet emerged.

What is beyond question is the enormous impact that Europeans have had since 1788, when the first English settlers drove in their tent pegs and set up corrals for their sheep and cattle.  The introduced livestock were the first animals with cloven hooves ever to walk on Australian soil. As a direct result, the biocrust, that is the beneficial communities of lichens, mosses, and bacteria which form on undisturbed soils in many arid lands, and indeed the top profiles of the soils themselves were quickly eliminated.

European settlers also cleared vast areas of land for grazing and crop lands, and introduced rabbits, cats, foxes, rats, mice, donkeys, camels, and other exotic animals  which have had horrific impact on small marsupials, birds, and reptiles of the island, not to mention the complex ecological networks and community dynamics in which those animals occurred. Sad to say, Australia has the worst record of any country for recent animal extinctions.

Cattle at a waterhole. Cockatoo Creek, Willare, Western Australia.

Unsupervised cattle at a waterhole. Cockatoo Creek, Willare, Western Australia.

Cleared and overgrazed land on a cattle station in Western Australia. The ribbon of woodland in the background provides a reference for what the whole area once looked like.

Cleared and overgrazed land on a cattle station in Western Australia. The ribbon of woodland in the background provides a reference for what the whole area once looked like.

Of the 60 mammal species that have gone extinct worldwide, in the last 200 years, 30 were Australian – and most inhabited the arid and semi-arid zone. Besides, a further 6 formerly widespread mammals are on the brink of extinction today, surviving only on handkerchief-sized, fenced off reserves or offshore islands inaccessible to feral cats and foxes.

While that is a terribly bleak legacy, promising steps are now being taken to limit the damage going forward, and ensure that the history of massive human-caused extinctions is not repeated. In our third and fourth blog posts from Australia we will discuss the obstacles to restoration, and then some of the encouraging endeavors underway.

The unexpected canopies of arid Australia

James and Thibaud Aronson report from Australia, where they went to study desert trees and on-going restoration efforts.

Australia’s deserts are like no others, we found. For one thing, they have tree canopies galore and a range of habitat types that one would not expect when looking at the generally flat topography. And they are vast. Australia’s ‘dry country’ occupies 60% of its area, or more, depending on your sources, that is roughly 5 million square km (1.9 million sq mi) or over half the size of the continental US.

Map of Australia's deserts. From Morton et al. (2011)

Map of Australia’s deserts. From Morton et al. (2011)

These huge regions stand on red or white sands with outcrops of granite, and other subtle but marvelous geomorphological jewels, and hide deep reserves  of iron, copper, bauxite, uranium, and of course, gold.  For two naturalists from the northern hemisphere, it’s like a candy shop: endless skies and landscapes, intriguing animals, and such an array of unique Gondwanan plants.

Very striking indeed was the remarkable diversity of trees in areas with less than 400 mm (12 in) mean annual rainfall, which is our rough and ready cutoff point for the book we are writing on dryland ecosystem restoration, with Edouard Le Floc’h. At present count, we will include at least 400 species of Australian trees, roughly a quarter of the total number of desert trees species, worldwide. But even more striking was the sheer amount of biomass in those trees and the extensive canopies they form, despite the infertile soils and highly unpredictable rainfall.

Eucalypts, the native cypress relative, Callitris sp., and the endemic tree cycad Macrozamia macdonnellii densely packed on rocky ridges. Standley Chasm, West MacDonnell National Park, Northern Territory.

Eucalypts, the native cypress relative, Callitris sp., and the endemic tree cycad Macrozamia macdonnelii densely packed on rocky ridges. Standley Chasm, West MacDonnell National Park, Northern Territory.

Remarkably dense woodland, away from water, in an area with 286 average annual rainfall. Serpentine Gorge, West MacDonnell National Park, Northern Territory.

Remarkably dense woodland, away from water, in an area with 286 mm average annual rainfall. Serpentine Gorge, West MacDonnell National Park, Northern Territory.

There are few mountain ranges, perennial rivers, and drainage systems, and yet, regardless of the scale of observation, arid and semi-arid Australia is remarkably heterogeneous. These deserts are also host to a wide array of beautifully adapted animals, including the remarkable “roos”, which come in all shapes and sizes, the blue-tongued lizards, and many more.

Two common wallaroos (Macropus robustus erubescens). Capre Range National Park, Western Australia.

Two common wallaroos (Macropus robustus erubescens). Cape Range National Park, Western Australia.

Spinifex pigeon (Geophaps plumifera). Karijini National Park, Western Australia.

Spinifex pigeon (Geophaps plumifera). Karijini National Park, Western Australia.

Shingleback lizard (Tiliqua rugosa). Corackerup Reserve, Western Australia.

Bobtail blue-tongued skink (Tiliqua rugosa). Corackerup Reserve, Western Australia.

Galah (Eolophus roseicapilla). This cockatoo is a nomadic inland species that has greatly benefitted from human land use changes to increase its range. Fraser Range station, Western Australia.

Galah (Eolophus roseicapilla). This cockatoo is a nomadic inland species that has greatly increased its range as a result of human land use changes. Fraser Range station, Western Australia.

One of the key areas we visited was where the desert meets the South-Western Floristic Region, which has one of the highest plant diversities on the planet, and is the only biodiversity hotspot in Australia.

This area is characterized by a large number of granite outcrops which act as fire barriers and constitute highly diversified, humid habitats with mosses, ferns and other surprises. Most remarkably, they host a significant number of both terrestrial orchids and sundews, a type of carnivorous plant, two groups we’ve never seen in arid areas anywhere before.

One of the many sundews (Drosera spp.) found in arid Australia. Kalbarii National Park, Western Australia.

One of the many sundews (Drosera aff. macrantha; fide K. Dixon) found in arid Australia. Kalbarri National Park, Western Australia.

Spider orchid (Caldenia dimidia). Norseman, Western Australia.

Spider orchid (Caladenia dimidia). Norseman, Western Australia.

This area is what Stephen Hopper – one of the most eminent plant scientists in Australia – calls an OCBIL , an acronym for Old, Climatically Buffered, Infertile Landscapes,  describing the relatively few places on Earth that for a very long time have not been rejuvenated either by orogenesis – mountain formation – or glaciation. This leads to very poor, infertile soils. Southwestern Australia, is one such place, and one that is under threat as well, given the huge pressure from the mining industry, wheat growers, pastoralists, and a government administration that seems to only think short-term.

In our next post, we will discuss a defining, and problematic process of Australian desert ecology, namely fire.

Reference cited:

Morton S., Smith D.S., Dickman C., et al. 2011. A fresh framework for the ecology of arid Australia. J. Arid. Environ. 75:313–329.