The Eco-index research programme: Aotearoa New Zealand’s answer for effective investment in biodiversity restoration

Catherine Kirby is the Communication & Relationships Manager for the Eco-index research programme as well as Programme Manager for the People, Cities & Nature research programme, part of the Four Islands EcoHealth Network. Here Catherine explains the novel approach of the Eco-index Programme and how it is focussed on reversing biodiversity decline on the islands of Aotearoa New Zealand.

Aotearoa New Zealand’s biodiversity has a unique story

Indigenous biodiversity in Aotearoa New Zealand is in dangerous decline – this is not a unique situation on the world stage. However, the story of how we got to this point and our planned approach towards recovery could be perceived as rather novel.

Kea (Nestor notabilis) – endemic to New Zealand and the world’s only alpine parrot. Credit: BioHeritage Challenge.

Our biogeographical story

The fascinating islands of Aotearoa New Zealand have been isolated in the Pacific Ocean for up to 80 million years. The islands are long and narrow, straddling latitudes from 34° to 47° south and encountering climates from subtropical in the north to subantarctic in far south. The country experiences a highly changeable climate that is coupled with wildly variable geographic features. In Te Ika a Māui – the North Island, landscapes range from white sandy beaches to active volcanoes and rugged western coast lines. While in Te Wai Pounamu – the South Island, you can encounter temperate rainforests, dramatic glacial fjords, dry open plains as well as the rugged Southern Alps.

This isolation, habitat and climatic variability in an island context has influenced the evolution of unique indigenous flora and fauna with a high degree of endemism (100% of frogs and reptiles, 90% of insects and approximately 80% of vascular plants) and a particular fragility and vulnerability to predation and competition from invasive non-native plants and animals.

Delicate flowers of the New Zealand endemic Pittosporum cornifolium. Credit: Catherine Kirby.

New Zealand’s National Science Challenges

Despite extensive reporting on biodiversity decline in Aotearoa New Zealand, an effective approach for reversing the loss of our special indigenous species has not been identified. This is where the National Science Challenges come in.

Established in 2014 by the New Zealand government, the 11 cross-disciplinary, mission-led National Science Challenges are working to address science-based wicked problems that researchers and residents are most concerned about. The Science Challenges focus on many aspects of society, the natural environment, the urban environment and economic development. They involve collaboration between universities, other academic institutions, crown research institutes, businesses and non-government organisations. Together, the Challenges will receive NZ$680 million (US$491.5 million) of government funding over ten years.

Biodiversity and biosecurity are central for New Zealand’s Biological Heritage National Science Challenge | Ngā Koiora Tuku Iho (or, ‘BioHeritage Challenge’ for short). The BioHeritage Challenge is focussed on discovering the most effective means of protecting and managing native biodiversity, improving biosecurity and enhancing resilience to harmful organisms. This work is centred on three core goals and is grounded in strong values that embrace partnerships with Māori (indigenous peoples of Aotearoa New Zealand):

The three core goals of the New Zealand’s Biological Heritage National Science Challenge | Ngā Koiora Tuku Iho.
Values of the New Zealand’s Biological Heritage National Science Challenge | Ngā Koiora Tuku Iho.

Introducing the Eco-index programme

The Eco-index programme is one of 14 research teams in the BioHeritage Challenge. With a focus on the Whakamana (Empower) goal, the Eco-index team is thinking outside the square to measure and direct land managers’ investment in ecological restoration.

Aotearoa New Zealand has a significant evidence base that biodiversity decline is occurring, but an effective countrywide approach to reverse this trend has not eventuated. A team of national and international experts from many different fields spent 6 months developing our novel Eco-index approach to address this issue and specified a starting with the formation of a long-term biodiversity vision, followed by a means of accomplishing the vision.

Kiwi (Apteryx australis) – flightless, nocturnal, and endemic to New Zealand. Credit: BioHeritage Challenge.

Eco-index 100-year national vision for biodiversity restoration

To guide long-term change, the Eco-index programme has developed a 100-year national vision that is informed by the targets, perspectives and strategies of biodiversity stakeholders across our nation, including iwi (Māori tribal groups), businesses, communities, NGOs, primary industries and governmental organisations.

The resulting shared vision for Aotearoa New Zealand is based on thriving, ecologically robust corridors of indigenous landcover that stretch from mountains to the sea. These biodiverse corridors will link our conservation estate with private and production landscapes and contribute to 15% of original ecosystem extent being restored, protected and connected in every catchment.

To contribute to methods for development of national restoration visions internationally, we are in the process of publishing our vision creation methodology in the primary literature.

Achieving the vision: linking biodiversity investment with impact

The Eco-index programme is utilising existing big data to quantify investment that land managers of all types are making to benefit indigenous biodiversity. These investments include restoration practices like native plantings, control of non-native invasive mammals (e.g., rats and stoats), protection of indigenous ecosystems, and planning work that goes into all of these. We are then linking this investment with big data indicating the impact these investments have on biodiversity. These data include indigenous species increases or decreases, especially those of importance to Māori, indigenous landcover, and human-nature connectedness. These links will be made at national, regional, iwi (Māori tribal groups) and industry scales and will provide:

  1. an overall score of Aotearoa New Zealand’s biodiversity status updated regularly and shown at different scales, therefore showing trends over time;
  2. biodiversity impact comparisons between industries and trends over time;
  3. determine overall investments needed for effective biodiversity restoration by key land managers (e.g., government, industries, iwi, NGOS);
  4. determine correlations between levels of investment in biodiversity restoration and levels of impact on biodiversity status nationally, regionally, and across industries;
  5. identify best or most effective biodiversity protection and restoration investments by major region and industry.
Children planting indigenous trees to benefit local biodiversity. Credit Catherine Kirby.

How is the Eco-index approach novel?

Our point of difference is that we are co-designing with key land managers across the country to understand what will help them most. A large proportion of indigenous ecosystems in Aotearoa New Zealand is on privately-owned agricultural land and many land managers are passionate about protecting and enhancing indigenous biodiversity but need to know best actions to take. Our programme will identify the most effective incremental investments that land managers (including iwi), as well as investors and communities, can make to generate the cumulative intergenerational impact needed to reverse decline. Creating and tracking this change using the Eco-index outputs will enable an effective, collective journey. 

In time, the Eco-index will indicate our Aotearoa New Zealand’s biodiversity performance, much like GDP indicates economic performance.

Current Eco-index focus – June 2021

The Eco-index programme runs from 2020 to 2024. We are building relationships with key land managers and data owners to co-design our approach and discover efficient ways to work together for the benefit of indigenous biodiversity. We are also developing methodology for gathering and analysing relevant biodiversity investment and impact data. The application of fast-evolving artificial intelligence and machine learning technology may be the key for cost-effective analysis of existing big data and satellite imagery across Aotearoa New Zealand.

About our team

We have expertise in Aotearoa New Zealand ecology, economics, sustainable development, land management systems and ecological restoration. The Eco-index team is led by Dr. John Reid (Ngāti Pikiao, Tainui, JD Reid Ltd.) and Dr. Kiri Joy Wallace (Te Pūtahi Rangahau Taiao – Environmental Research Institute, University of Waikato).

Keep up to date!

Interested in the Eco-index programme? See more at www.eco-index.nz and like/follow us on Facebook and Twitter to be updated on our progress and discoveries:

Conserving and restoring Missouri bladderpod, a US Midwestern endemic

Matthew Albrecht is a Scientist in the Center for Conservation and Sustainable Development at Missouri Botanical Garden. Here he describes a recent fieldtrip to the Ouchita Mountains to study outlying populations of the federally threatened Missouri bladderpod, Physaria filiformis.

Situated between Rocky Mountains to the west and the Appalachians to the east lies the often overlooked Ouachita (pronounced WAH-shi-tah) Mountains of central and western Arkansas and adjacent Oklahoma. Unlike the Rocky and Appalachian Mountains, the Ouachitas are a relatively small mountain chain that trends primarily east-west. Despite occupying a relatively small area, the Ouachitas harbor a large proportion of the region’s plant diversity and represent a remarkable center for endemism including many rare plants species with extremely narrow distributions.

On a recent spring afternoon, Christy Edwards and I had the opportunity to visit the relatively rare and poorly studied shale outcroppings of the Ouachitas with botanists Brent Baker and Diana Soteropoulos of the Arkansas Natural Heritage Commission. In the Ouachitas, shale formations outcrop on gentle to steep south- or west-facing slopes and occasionally on gently sloping drainages. Upon first glance, these outcroppings with exposed fragments of thin, black shale and patches of sparse vegetation cover appear somewhat other worldly. Upon closer inspection, one finds tucked between shale fragments a number of xeric-adapted herbaceous species capable of surviving in this harsh environment, where the dark, sun-scorched shale at the surface creates extreme ecological conditions.

Ouachita shale glade and barrens. Photo by Matthew Albrecht.
Xeric-adapted species specialize on the thinnest soil portions of shale outcrops. Photo by Christy Edwards.

Shale barrens and glades are mosaic plant communities consisting of a remarkable number of endemic, rare, and narrowly-distributed species. According to NatureServe, 36 plant species of state conservation concern and more than 20 globally critically imperiled, imperiled, or vulnerable species occur in this system. New species are still occasionally discovered and a few species remain undescribed in the Ouachita shale barrens. For example, we saw a striking purple-flowered undescribed species of wild hyacinth (Camassia sp. nova) during our visit.

An undescribed wild hyacinth (Camassia sp. nova) growing in a shale glade and barren complex owned and managed by the Ross Foundation. Photo by Matthew Albrecht.

The star of the show that day and the focus of our research expedition to the Ouachitas was the federally threatened Missouri bladderpod (Physaria filiformis).  Many members of the genus Physaria – commonly known as bladderpods due to their inflated seed pods – are recognized for their narrow distributions and edaphic endemism, or restriction to unusual soils. As a small-statured winter annual, Missouri bladderpod showcases brilliant yellow flowers in early spring and specializes on thin-soiled calcareous (dolomite and limestone) outcrops in northern Arkansas and southwestern Missouri. However, at its southern range limit in the Ouachitas, Missouri bladderpod is known from just a few isolated shale glades and barrens.

A profusion of flowering Missouri bladderpod (Physaria filiformis). Photo by Christy Edwards.
Missouri bladderpod (Physaria filiformis) displaying inflated fruits on a shale outcropping. Photo by Matthew Albrecht.

Prior to visiting the Ouachitas I wondered how a presumed calciphile like Missouri bladderpod existed on shale formations, which typically produce acidic soils. Perhaps like a few other species of rocky outcrops in the region – such as Sedum pulchelum (widow’s cross), and Mononeuria patula (lime-barren sandwort) which occur on both acidic and calcareous substrates – I surmised MO bladderpod may also tolerate a broader range of edaphic conditions than previously thought. However, I soon learned the shale outcroppings we visited were interbedded with limestone and supported other calciphilic indicator species such as Ophioglossum engelmannii.

A case of cryptic speciation in the Ouachitas

Once known only from limestone glades in southwestern Missouri, botanists over the years have discovered populations of Missouri bladderpod on limestone, dolomite, and shale outcroppings in scattered locations throughout Arkansas, denying Missouri’s claim of its only endemic species. A recent study led by Christy Edwards at the Missouri Botanical Garden examined range-wide (Arkansas and Missouri) genetic variation in Missouri bladderpod and the degree of genetic differentiation among populations on limestone, dolomite, and shale. Interestingly, genetic data showed isolation by distance – meaning that as geographic distance increased among populations so too did genetic differentiation. Most strikingly, the geographically isolated shale populations in the Ouachitas were highly genetically divergent from dolomite and limestone glade populations further north in Arkansas and Missouri. This strong pattern of genetic differentiation points to a possible cryptic speciation event in the Ouachitas and a previously unrecognized extremely rare species. On one hand, the genetic data was somewhat surprising given there are no obvious morphological differences among Ouachita shale populations and P. filiformis. Conversely, the data do support the remarkable pattern of narrow-endemism observed throughout the Ouachita Mountains. 

As we trekked across Arkansas for a few days – along with Brent and Diana who generously shared their time and expertise – collecting fresh material of Missouri bladderpod for a deeper research dive into whether morphological traits differentiate this previously unrecognized cryptic species in the Ouachitas, the need to conserve and restore glade habitat became ever clearer. At present, there are only three known Ouachita populations, making this cryptic species extremely rare and vulnerable to extinction. Many shale glade and barrens systems are now severely damaged or have been destroyed by mining activities. Fortunately, the largest population we visited consisted of thousands of plants scattered across a shale glade and barrens complex that has been restored and managed with fire and woody thinning by the Ross Foundation. In the absence of periodic, appropriately-timed prescribed burning, glades and barrens slowly become encroached with woody species that eventually choke-out sun-loving plants like Missouri bladderpod.

A large, restored shale glade and barrens complex in the Ouachita Mountains.

Other populations of Missouri bladderpod eek out an existence on small stretches of outcrops on roadsides or private property maintained as cattle pasture. These sites prove challenging to conserve and restore. Sadly, we did visit some sites where populations were barely surviving due to degraded habitat conditions. However, two sites we visited gave us a glimmer of hope that Missouri bladderpod will continue to survive and thrive. First was a newly discovered dolomite glade population on private property in north-central Arkansas. The property owners recently thinned woody vegetation and began prescribed burning to restore their glade and woodland ecosystem. When we visited, Missouri bladderpod was thriving after a recent prescribed burn. Similarly, the second site we visited on public property had been thinned and burned in recent years, resulting in a diverse plant community and flourishing Missouri bladderpod population. These success stories illustrate the importance of restoring degraded habitat to conserve our rarest components of biodiversity.

Population of Missouri bladderpod growing on a roadside dolomite outcropping and pasture in north-central Arkansas.
A degraded site with woody encroachment and a small, declining population of Missouri bladderpod.
A restored hillside glade with a thriving population of Missouri bladderpod.

To learn more about the Missouri bladderpod, read the new, open access paper by Christy Edwards, Matthew Albrecht and others.

Botanizing a Central Appalachian Shale Barren

Leighton Reid describes a field trip to a unique, natural community with Tom Wieboldt, retired curator of the Massey Herbarium at Virginia Tech.

From southwestern Virginia to central Pennsylvania, ancient shale formations jut out of the mountains at wonky angles. Loose and crumbly, the rocks bake in the sun. Surface temperatures can reach 60° C (140° F) – comparable to a desert. Rocks slip and tumble easily on the steep slopes. Few eastern plants are tough enough to hack it under these conditions. Among those that can, a few are globally unique.

On a warm day in August, I had the opportunity to botanize one such place – a central Appalachian shale barren in Craig County, Virginia – with Tom Wieboldt, retired curator of the Massey Herbarium at Virginia Tech (VPI), and a leading authority on shale barren flora. As we hiked and photographed plants, we talked about the conservation and potential for ecological restoration of these rare communities.

Shale barren wild buckwheat (Eriogonum allenii), a central Appalachian endemic whose relatives are mostly west of the Mississippi.

The gems of the shale barrens are the endemics. Amazingly, 22 species are found mostly or exclusively on central Appalachian shale barrens. Another seven species are rare or disjunct from the rest of their range – typically far to the west. For example, the closest population of chestnut lip fern (Cheilanthes castanea) outside of Virginia and West Virginia is in Oklahoma.

Virginia white-haired leatherflower (Clematis coactilis), a Virginia endemic and one of three leatherflowers endemic to central Appalachian shale barrens.
Shale-barren ragwort (Packera antennariifolia) had already finished flowering by August, but its leaves lived up to their name, looking very much like pussytoes (Antennaria sp.). This plant is strictly endemic to shale and metashale barrens.
Kates Mountain clover (Trifolium virginicum) was long thought to be a shale barren endemic, but it also occurs (rarely) on other substrates.
Shale barren evening primrose (Oenothera argillicola), a strict shale barren endemic.
The teeny-tiny flowers of mountain nailwort (Paronychia montana), a plant that is not quite endemic to shale barrens. It also occurs on a variety of other substrates.

Shale barren plant communities exist in a dynamic equilibrium. The steep, brittle shale formations often are under-cut by rivers, which carry away rocks and cause further erosion. In essence, the entire slope is constantly slipping downwards. Successful plants find the most stable areas and send down deep roots to try to keep their place on the rocky conveyor belt.

Why do shale barrens occur only in the Central Appalachians and not also in the Southern Appalachians? Tom gave me two reasons. First, the shale deposits in the Central Appalachians get thinner south of Montgomery County, Virginia, where Virginia Tech is located. Second, the high Allegheny Mountains in West Virginia create a rain shadow over parts of the Central Appalachians, more so than the more southern and shorter Cumberland Mountains. Drier conditions in the Allegheny rain shadow contribute to the shale barrens’ uniquely western ambiance.

Inhospitable as they are, shale barrens are not immune from human pressures. They are sometimes crossed by roads or utilities, and shale banks are sometimes quarried for road-building material. Livestock and overpopulated white-tailed deer browse the plants and catalyze erosion, while also adding nitrogen and foreign seeds to the sparse soil.

Craig Creek undercuts several shale bluffs, hastening their erosion and creating the conditions for shale barren plants to flourish.

Can disturbed shale barrens be restored?

When Reed Noss visited a Virginia shale barren for his book Forgotten Grasslands of the South, he found traversing the slippery slopes, lurching from one scattered red cedar to another, “close to suicidal”. I had similar thoughts following Tom up the mountainside. He climbed like a mountain goat, wandering out on thin ledges to collect interesting looking mosses.

Tom Wieboldt collects an interesting-looking moss from the side of a crumbling cliff.

As we walked, Tom wondered aloud whether it would even be possible to restore such a fragile plant community if it was destroyed. Wouldn’t it be better just to leave these places alone?

Undoubtedly leaving these places alone would be better. But I enjoyed thinking about how one might restore a shale barren that had already been destroyed – by quarrying, for instance. A first step might be to recontour the slope, aiming to reestablish a dynamic equilibrium with some areas eroding more actively than others. Perhaps this could be done by a skilled operator with some of the same quarrying equipment that had previously exploited the loose shale.

To revegetate such a place would require a source of propagules. I am teaching a course on Plant Materials for Environmental Restoration, so I put it to my students to find out whether shale barren plants were available from two major conservation seed suppliers. The results were not promising. Out of 86 native, non-woody angiosperms found in central Appalachian shale barrens*, less than a quarter (23.3%) could be purchased from any major seed supplier, and only 2.3% were available as seed collected from Virginia. None of the endemics were available.

As far as I can tell, few shale barren restorations have been undertaken, but I did read about one attempt in a shale barren in Green Ridge State Forest, Maryland. Whereas some shale barrens are actively threatened by acute pressures, like quarrying, this small (0.6 ha) barren was passively threatened by steady encroachment from the surrounding forest. Trees, especially pignut hickory (Carya glabra), were growing into a formerly open barren, stabilizing the soil and cutting off direct sunlight to plants closer to the ground. Managers restored the site in 2010-2011 by removing some of the pignut hickories and by burning the area during the winter. Together, these actions resulted in greater herbaceous vegetation cover and greater species diversity.

Central Appalachian shale barren, Craig County, Virginia, with a mix of shale barren wild buckwheat (Eriogonum allenii) and hairy lip fern (Cheilanthes lanosa) dominating the foreground.

Thanks to Tom Wieboldt for a fun field day, an excellent guest lecture, and stimulating discussions about botany, conservation, and restoration. To learn more about this unique natural community, read Tom’s co-authored chapter about shale barren communities in Savannas, Barrens, and Rock Outcrop Communities of North America, or Reed Noss’s chapter on shale barrens in Forgotten Grasslands of the South.

*For the seed availability exercise, we used the list of plants recorded by the Virginia Natural Heritage Program in their description of Central Appalachian Shale Barren (Shale Ridge Bald / Prairie Type) CEGL008530. We excluded woody plants, non-native plants, and ferns.

Desert Trees of the World – A new database for ecological restoration

For the past five years, James and Thibaud Aronson have been traveling to the driest parts of the world to collect data about the distribution, ecology, uses by humans, and up-to-date systematic botany of  the soul-satisfying and mind-boggling trees that grow in Earth’s beleaguered, beloved, and mega-diverse drylands. Here they describe the content and purpose of their new Tropicos database. This work builds on more 3 decades of collaboration between James and Edouard Le Floc’h, who is also a co-author of the database and a book-in-progress on desert trees and their role in ecological restoration and allied activities.

Desert Trees of the World represents a multi-purpose, participatory database in which we have gathered a vast array of information about dryland trees, where and how they live, the communities they are part of, the many ways in which they are used by people, and some elements about their successful cultivation.

Our database brings together the most up-to-date botanical, biogeographical, ecological, and ethnobotanical information on 1576 species of trees from the arid and semi-arid regions of five continents and many islands. And because it is hosted on Tropicos, the Missouri Botanical Garden’s vast botanical database, a user can seamlessly access any supplementary information that may be available for a given species thanks to research carried out in other MoBot projects. Further, maps of collection sites, as well as full nomenclatural, bibliographic, and voucher specimen data accumulated digitally at MBG these past 30 years are available.

The data base is intended for students of natural history, practitioners, policy-makers, and scientists working in ecological and biocultural restoration, conservation, and sustainable and restorative environmental management.

Trees in the desert?

Most people think that deserts are – by definition – devoid of trees. Not true! Indeed, some of the strangest, oldest, and most remarkable tree species on the planet are found in drylands, a term often used to refer to deserts and semi-deserts, also known as arid and semi-arid lands.

For our purposes, drylands are all the lands of the globe that receive less than 400 mm (ca. 16 inches) of rain in an average year. In total, this concerns over 42% of all lands on Earth, so listing all the tree species that occur in them was no small task! But, we were drawing on decades of travel, research and residence in quite a spectrum of the world’s deserts and semi-deserts. We also pored over specimens housed in three dozen major herbaria, and read thousands of technical scientific articles and floras in several languages. And, as this is the 21st century, we used information already online in another Tropicos project, the Catalogue of the Flora of Madagascar as well as many other online sources.

Saguaro and boojum

A cardón (Pachycereus pringlei) and a boojum (Fouquieria columnaris) in the Central Desert of Baja California, Mexico. In the harsh conditions of deserts, evolution has favored some of the strangest-looking trees on the planet.

Boswellia Oman

In southern Oman, we explored the remote Wadi Aful, where wild frankincense trees (Boswellia sacra) grow between sheer rock walls.

Astrotricha hamptonii

The irontree (Astrotricha hamptonii) is not among the most impressive-looking desert trees in our database. And yet, because it only grows on ironstone formations, clever prospectors used its distribution to discover some of the largest iron ore deposits in Western Australia.

Since there had been no previous attempts at documenting the trees of all the deserts in the world, we weren’t sure how many species we would end up with. And the end result was truly remarkable: a sum of 1576 species of trees native to deserts around the world, occurring in  422 genera and 100 families of flowering plants. Of course, new tree species are still occasionally being discovered, mainly coming out of Namibia, Somalia, and southern Arabia, but we are confident that we have captured the great majority of all extant dryland trees in this database.

jordan woods

Then again, some desert trees are not so unfamiliar to visitors from Europe or North America, such as these junipers (Juniperus phoenicea) and oaks (Quercus calliprinos), growing in the central mountains of Jordan.

What does a desert tree look like?

If asked about what a desert tree looks like, you might think of spiny or resinous, sticky trees. And you would be right. Fabaceae, the legume family, make up just over a quarter (403) of all species, and of those, 217 are Acacia sensu lato. The next ‘big’ family is the Myrtaceae (the Eucalyptus family), with 133 species, all but one found in Australia, the exception, Myrcianthes ferreyrae, being restricted to the fog oases of Peru’s hyper-arid coast. And in third place are the Burseraceae, with 111 species. This is the family of myrrh and frankincense, two desert trees whose importance for humans dates back millennia, tied as they are to the great cultures of the Old World. For reference, people’s most common images of desert trees are palms (think – oasis) and tree cacti. But there are only 28 desert palm species, and 49 tree cactus species.

We also have some remarkable oddities, such as one arborescent member of the cucumber family (Dendrosicyos socotrana), and several rose relatives (Polylepis spp.) that grow above 4000 meters in the most parched areas of the Andean cordillera!

Where do desert trees grow?

Interestingly, the different desert areas of the world are not equal in terms of their contributions to our database (see the table below, the full version of which is posted on the homepage for our database).

Region Number of Species Endemic species* Number of Genera Number of Families
Australia 389 373 62 34
Madagascar 355 311 160 55
North America 272 222 126 55
Northeast Africa 233 80 87 42
West Asia 224 86 97 46

*Endemic to the country or region indicated.

Five regions alone account for two thirds of all the species in our database, with the deserts of Australia and Madagascar being almost preposterously rich in tree species. But of course the area of arid Australia is vastly greater than that of Madagascar, so that in fact the numbers of families, genera and species in the latter country are really the most impressive of all.

 

baobabs Mada - pete

Highly degraded spiny thicket vegetation at the edge of the Ranobe PK32 Protected Area near the town of Ifaty, in western Madagascar, with few trees other than the emergent baobabs, Adansonia rubrostipa (Malvaceae) remaining. Young plants of the spiny tree, Didierea madagascariensis (Didiereaceae) developing in the bare sandy soil around the baobab in the foreground. 11 September 2006. © Peter Phillipson, Missouri Botanical Garden. http://www.tropicos.org/Image/100624586.

spiny thicket - pete

Secondary growth spiny thicket near the Ranobe PK32 Protected Area north of Toliara, in Madagascar, with occasional individuals of the locally endemic spiny tree Pachypodium mikea (Apocynaceae) – center image, but dominated by mature Didierea madagascariensis (Didiereaceae). 03 December 2018. © Peter Phillipson, Missouri Botanical Garden.

A zoom on the astonishing dryland tree species richness and diversity of Madagascar can already be found in an article we published last year, covering the remarkable assemblages of 355 tree species found in the driest part of Madagascar, of which no less than 311 are endemic to the country. This is all the more remarkable considering that they are all crowded into a narrow coastal strip in the Southwest, which is a mere 14,480 square kilometers (5591 square miles), or the same size as Connecticut.

For us, a key feature when discussing desert trees is the fact that even in the harsh areas where they found, trees can grow densely enough to form true woodlands, sometimes even with dense canopies, which has enormous importance for desert ecosystems and people. In previous blog posts we have reported on striking examples – in northeastern Jordan, and coastal Peru, among others, where evidence of former woodlands provide rays of hope and guidance for people attempting ecological restoration in desert lands.

Back in 2013, James and Edouard published a first book in French (Les Arbres des Déserts: Enjeux et Promesses) profiling desert trees and developing the subject of desert woodlands. We now have a more comprehensive book in preparation, called Desert Canopies: Reimagining our Drylands. Three chapters on animal-tree relations, and photos and drawings by Thibaud will help make this of interest for a wider audience, not just specialists. We also develop the theme of ecological restoration and provide profiles and virtual field trips from many restoration programs in drylands around the world.

 Where can one see living Desert Canopies today?

Unfortunately, most drylands are found in poverty-stricken regions of developing countries, where trees are an extremely valuable resource. In recent decades, desert canopies have been hammered by rising populations of people and livestock. As a result, today these canopies are so degraded and fragmented that it’s hard to imagine what they once looked like. Western Australia is one of the few places where reasonably intact desert woodlands still cover large areas.

Great western woodlands

A typical landscape of the Great Western Woodlands, in the semi-arid southwest of Australia (mean annual rainfall 250 – 400 mm), with gimlet eucalypts (E. salubris) growing over a beautiful understory of blue bush daisy (Cratystylis conocephala).

In our last blogpost, we reported on some notable trees, tree canopies, and indigenous peoples of the Guajira peninsula in northern Colombia.

macuira stream

From looking at the tree cover, it is hard to believe that this area of Colombia is technically a desert!

wayuu family

Young Wayuu and their donkeys, standing in the shade of a tree, on their family farm in the Serranía de Macuira, a mountain oasis in the middle of the Colombian desert. The Guajira, as the region is called, is a microcosm of the problems and drivers of arid lands everywhere, as well as a good example of the diversity and life and beauty that can be found in deserts.

Other striking tree canopies can still be found in diverse places today, including some of the driest places on Earth.

Prosopis cineraria

The Rub al Khali, the famous Empty Quarter of Arabia. Even there, trees can thrive amid the sand dunes (in this case, the venerable khejri, Prosopis cineraria), that we were lucky enough to observe in northern Oman.

Prosopis pallida Peru

On the arid coast of northern Peru, Prosopis pallida and other trees can grow in the ever-so-slightly richer soils at the bottom of gullies amid the plains.

As noted earlier, drylands make up more than two-fifths of all lands on Earth, at present. Furthermore, despite their harsh conditions, drylands are presently home to well over 2 billion people, and indeed many of these are among the poorest and most vulnerable populations on Earth. The United Nations, and many other organizations are working hard on the problems of drylands and their peoples, but it is very much an uphill battle… As we passed Earth Overshoot Day on July 29th this year– the earliest date ever – it is timely to stress once again that the restoration and rehabilitation of degraded ecosystems will be key if we are to hope for a sustainable future. Restoration is undeniably harder in arid lands than in many other places, but that only means that it is more necessary. We are happy to relate that the Society for Ecological Restoration’s scientific journal, Restoration Ecology, is launching a new initiative devoted to dissemination of scientific advances on ecological restoration and rehabilitation in arid lands. Our database is offered in that spirit.

isla guadalupe

The small, arid Isla Guadalupe, off the coast of northwestern Mexico, is home to several endemic tree species, which were almost extirpated by introduced goats. But now that the goats have been removed from the island, the trees are making a comeback. Pictured here is the endemic cypress Cupressus guadalupensis, and some of the people who’ve made this recovery possible.

A large number of the trees included – 932 out of 1576 to be exact – are endemic to a single country – and most are in urgent need of committed conservation, restoration, and better management. We hope that our database can act as a reminder of the wealth of life forms that can thrive in arid lands, and an exhortation to not give up on their desert homes, scarred and battered as they may be, but rather to try and help them flourish once again.