The importance of knowledge of cultural values for dryland ecological restoration: Lessons from Argentine Patagonia

Fernando Farinaccio, Eliane Ceccon and Daniel Pérez, describe the importance of documenting cultural values, in the use of native flora, as a contribution to the restoration of drylands. Fernando is a researcher at the Laboratory for the Rehabilitation and Restoration of Arid and Semi-arid Ecosystems (LARREA), Argentina. Eliane is a researcher at the Regional Center for Multidisciplinary Research at UNAM (National Autonomous University of Mexico), Mexico, and Daniel is the scientific director of LARREA.

NB. LARREA belongs to the Faculty of Environmental and Health Sciences of the National University of Comahue, Argentina, where sixteen researchers and collaborators study selection of species for the recovery of sites with severe disturbance, seed-based restoration, interactions between exotic and native species, agroecological systems, and restoration-based education.

The extreme socio-ecological transformation and degradation of vast areas of arid Argentinean Patagonia has its origin in the 1880s when the Argentine government carried out an official program of extermination of all Indigenous Peoples (ignominiously called the “Desert campaign”). The goal was to consolidate political dominance over the coveted territories and to expand livestock production.

As elsewhere, this genocide led to a tragic loss of human lives and the uprooting and dispossession of native inhabitants who had lived in and managed this country for millennia prior to the arrival of the Europeans – most of whom had little or no understanding of the natural dynamics of this arid and semiarid territory or in the lives and cultures of the peoples who lived there.

Aguada San Roque, an isolated rural settlement of 160 inhabitants, extends over an area of 142,000 hectares in an arid basin called “Añelo basin” in northern Patagonia. It is characterized by high altitude variability, from 223 to 2258 meters above sea level, over a linear distance of 50 km. This town is in one of the most arid ecosystems of Argentina called ‘Monte’ (Busso and Fernández 2017). This ecosystem covers 20% (approximately 50 million hectares) of Argentina. The Monte has an annual average temperature of 12°C, with a high thermal amplitude and an annual temperature range from 40°C to −13°C (Coronato et al. 2017). The relationship between precipitation and potential evapotranspiration ranges from 0.05 to 0.5, indicating a strong water deficit.

“Jarillas” (Larrea spp.; Zygophyllaceae; creosote bush, in English) are the shrub species that give the typical appearance of most natural environments of Aguada San Roque. The dominant species of jarilla (L. divaricata, L. cuneifolia, and L. nitida) can reach approximately 2 meters in height when mature. For the attentive eye, it is probable that hybridizations between them have occurred and generated, among others, the striking “dwarf jarilla”(Larrea ameghinoi), that only reaches 20 to 30 cm in height.

Photo 1. Larrea divaricata. Typical of the natural environment around Aguada San Roque, Patagonia Argentina. Credit: Daniel Pérez.

Photo 2. “Dwarf Jarilla“ (Larrea ameghinoi).A species present in some areas of the Añelo basin. Its biology and reproduction  are very poorly known, but like all Creosote bush species in southern South America and the arid regions of North America, they have enormous influence on ecosystem functioning. Credit: Daniel Pérez.

Despite the aridity of the Añelo Basin, where it rains only 150 mm (6 inches) a year on average, with some years of only 50 mm, the beauty of nature is starkly visible to those who pay attention to details, and its mystery is slowly being revealed through scientific studies of the surprising and wonderful  strategies of plant and animal adaptations to aridity and drought. For example, Grindelia chiloensis (Asteraceae) known as “yellow love” or “honey-eyed” surprises and intrigues with its sticky stems, leaves, and flowers, all bearing so much resin that it is perceptible to the slightest touch. This trait is the result of biochemical efforts to manufacture organic compounds to avoid water loss. Fully 1/3 of the dry weight biomass of individual Grindelia shrubs is made up of these dense resins that allow it to adapt and thrive under the most arid and – importantly – degraded environments.

Photo 3. Detail of the flower of Grindelia chiloensis. Credit: Paul Alvarez.

A species that has probably been benefiting from the advance of wind deposits that multiply due to overgrazing is the “Patagonian lily” (Habranthus jamesonii; Amaryllidaceae). This plant is only noticeably visible in spring, as it develops from bulbs that remain under the sand during periods of unfavorable weather.

Photo 4. Habranthus jamesonii plant and flower in a sandy environment near Aguada San Roque. Credit: Daniel Pérez.

A plant that is almost white in color due to saline exudates is Atriplex lampa; Chenopodiaceae; a member of the widespread arid lands Saltbush genus that rewards the watchful eyes of the desert dwellers (Photo 5). This species has a profuse annual production of fruits with two small bracts that act as ‘wings’(Photo 6).

Photo 5: Atriplex lampa, typical of Monte desert landscapes, with fruits (almost yellow) in spring. Credit: Daniel Pérez.

Photo 6: Fruits of Atriplex lampa. Two bracts act as wings, facilitating their flight and dispersal by the wind. Credit: Paul Alvarez.

In very saline and clayey soils of our region, Halophytum ameghinoi (Halophytaceae) is very common. This species accumulates water in its stems and leaves as a strategy to withstand droughts. Their colors vary from intensely red to green tones during the juvenile and adult growth phases (Photo 7).

Photo 7: Juvenile individual of Halophytum ameghinoi. The increase in salty soils due to degradation will probably increase the amount of natural habitat for this species. Credit: Daniel Pérez.

Sadly, Aguada San Roque, like all the neighboring settlements, is seriously affected by long-standing desertification and degradation processes. Recently, the exploitation of large deposits of shale gas and oil, using fracking technology in the geological formation called “Vaca Muerta”, has revitalized economic activity, but also has induced a new and severe wave of environmental damage both underground and on the surface.

Photo 8: The preparation of land for the extraction of hydrocarbons entails a tremendously brutal action that spells disaster for biodiversity, ecosystem ‘health’ and, ultimately, human health and wellbeing. Credit: Daniel Pérez.

Photo 9: The action of the goats is not perceived with the same sensation of negative impact as that of the heavy machines engaged in fracking. However, overstocking of domestic livestock also causes irreversible damage. Credit: Daniel Pérez.

Photo 10: Frequent dust storms are one of the consequences of overstocking livestock. Aguada San Roque. Credit: Fernando Farinaccio.

Photo 11: A barchan dune, an example of the intense erosive processes in the vicinity of the Aguada San Roque settlement. These natural processes are exacerbated by overgrazing and intense hydrocarbon extraction activity. Credit: Eliane Ceccon.

Therefore, in this region, it is essential to plan and carry out ecological restoration and rehabilitation projects and programs that take into account the harsh socioeconomic conditions of the local population and include them in the process from the beginning. Fully 24% of the inhabitants – all of whom are of “criollo” origin – live in stark poverty, and more than 30% are illiterate. Life for these people is truly precarious, with little or no easy access to potable water and gas, and only 15% have electricity in their homes. Despite these conditions, the families that live there show an admirable desire to find ways of life that will allow them to continue inhabiting these arid lands.

Photo 12: Irma and Adalberto are owners of more than 9000 hectares of arid lands dedicated to raising goats in the Aguada San Roque area. They were unable to finish their basic studies in school and they have very limited income from the goats that they sell in informal markets. They are typical puesteros, or small scale farmers, of the region. Credit: Eliane Ceccon.

Photo 13: Irma roams the arid lands trying to prevent predators such as pumas (Felis concolor) and foxes (Lycalopex culpaeus) from attacking her goats, while directing and herding them to the few locations that can provide intermittent supplies of forage and water. Credit: Eliane Ceccon.

Therefore, due to the dire socioeconomic conditions mentioned above, it is necessary to conceive and launch sustainable restoration and rehabilitation projects that in addition to recovering ecological processes and functioning must also offer tangible goods and services to the local human population. In this sense, what we call “productive restoration” may be the most appropriate strategy, since it aims to recover soil productivity and offer products for the local population, along with some of the elements of the structure and function of the pre-disturbance ecosystem. (This is comparable to ecological rehabilitation as the term is used in the Society for Ecological Restoration Primer; SER 2004).

As mentioned, a critical key to successfully developing productive restoration projects in San Roque and other settlements in Argentinean Patagonia is to know and understand the socio-ecological context of the local population, in cultural, educational, health, and socio-economic terms, and also the values that local people assign to native plant species. We carried out surveys and interviews among the local inhabitants and visits to each of their landholdings, which allowed us to evaluate the knowledge and the value that they gave to the local flora, and their interest in cultivating native (and introduced) species in future restoration projects. The ecological attributes of selected species, and their importance for the productive restoration were obtained through a literature review. This review arises as part of Fernando Farinaccio’s PhD work. For more details and information, read his open access paper in Ecosystems and People.

Photo 14: Sometimes family settlements are located in places where there is an outcrop with easy access to groundwater (for example, a natural spring).This settlement recently benefited from government subsidies to improve water storage, allowing them to purchase and install the two water tanks shown here. Credit: Eliane Ceccon.

Local knowledge and use value of the native flora

Puesteros that we interviewed identified a total of 44 multipurpose species, of which 38 were native. Among the most frequently mentioned native species, Prosopis flexuosa var. depressa, Atriplex lampa, and Larrea spp., were considered by puesteros to have the highest potential and promise to restore and rehabilitate their fields and landholdings. The main reasons were not only ecological, but also the multiple uses of the plants, such as providing high quality fodder for livestock, and firewood for heating and cooking.

Photo 15: A portion of a plantation of Atriplex lampa (a nutritious and palatable native shrub) carried out in 2012 in a degraded area near Aguada San Roque. A recent study has proposed this species as a “framework species” for dryland ecological restoration (Pérez et al. 2019). Credit: Laboratory for the Rehabilitation and Restoration of Arid and Semi-arid Ecosystems, National University of Comahue, Argentina.

Ecological attributes for the reintroduction and reinforcement of populations of the plant species most valued by puesteros

According to studies carried out locally, the most valued species show high and easy germination (with rates of >60%) and are relatively easy to propagate in plant nurseries (see Farinaccio et al. 2021). In addition, some of them have shown high success in terms of survival and growth in field experiments (>70%) (see Pérez et al. 2019; 2020). These species are attractive because they are food sources for vertebrates and invertebrates, and also offer thermal refuge and nest sites for seed dispersers (Farinaccio et al. 2021).

Characteristics of puesteros‘ home gardens

Home gardens are traditional agroforestry systems supporting subsistence of poor rural families, and they are usually located near people’s homes. These home garden shave also been the cradle for selection, domestication, diversification, and conservation of elements of flora and fauna, and the preservation of cultural values. In the puestero’s home gardens, a total of 44 species were identified, of which 85% were exotic, and used to obtain forest products (from afforestation), 47% for shade and other amenities, and only 40% to obtain forage, food, and medicine.

Photo 16. Puesteros often use exotic trees in their home gardens. The most frequently used species are Eucalyptus spp., Populus spp., and Tamarix ramosissima, all of which are used for shade and wind breaks. Credit: Fernando Farinaccio.

Photo 17. In some home gardens, small areas marked off with wooden or iron fences are used for the production of fruit trees, medicinal species, and forage (A). The cultivation of species for food consumption is also carried out (B), and in some cases, these species are protected from inclement weather (e.g., intense winds, and extreme low and high temperatures), through the construction of small greenhouses (C). Credit: Fernando Farinaccio.

Conclusions

The socio-ecological, economic, and cultural contexts of the Aguada San Roque community showed an unfavorable well-being panorama. Likewise, the extensive livestock production system, on which all puesteros’ depend for their subsistence, added to the intense hydrocarbon activity (fracking), have triggered an irreversible desertification process. In this context, local people recognize a low percentage of useful native species and prefer to use a large proportion of exotic species.Similar results have been documented in other studies in drylands of Argentina and the world. The low results regarding the use of native species by the local inhabitants, and the preference in the use of exotic species, show a loss of traditional ecological knowledge, which could be a consequence of the above-mentioned historical occupation of arid Argentinean Patagonia. However, they expressed motivation and interest in sharing their historical practices with restoration actions with multipurpose native species. Beyond this unfavorable panorama, the puesteros expressed motivation and interest in carrying out restoration and rehabilitation actions with multipurpose native species. The three species most frequently mentioned by the puesteros (Prosopis flexuosa var. depressa, Atriplex lampa, and Larrea spp.), were all successfully established in ongoing restoration pilot studies.

This study proposes that the interpretation of the historical, social, cultural, and ecological reality of local people is fundamental before undertaking ecological restoration and rehabilitation programs. “Top down” programs may not be successful if the local inhabitants’ needs, desires, and proposals are not taken into account. A restoration-based education program can help implement these projects successfully. The program may promote the strengthening of local capacities and the rescue of traditional knowledge; increase collective learning, to ultimately restore the historical links between local people and the native, natural ecosystem.

References cited and additional reading

Busso, C.A., O.A. Fernández. 2017. Arid and semi-arid rangelands of Argentina. In: Gaur, M.K., V.R. Squires, editors. Climate variability impacts on land use and livelihoods in drylands. New York: Springer InternationalPublishing; p. 261–291.

Coronato, A., E. Mazzoni, M. Vázquez, F. Coronato. 2017. Patagonia: una síntesis de su geografía física. Santa Cruz (Argentina): Editorial de la Universidad Nacional de la Patagonia Austral. ISBN 978-987-3714-40-5.

Farinaccio, F.M., E. Ceccon, D.R. Pérez. 2021. Starting points for the restoration of desertified drylands: puesteros’ cultural values in the use of native flora. J Ecosystem & People. 17:476-490. https://doi.org/10.1080/26395916.2021.1968035

Pérez, D.R., F.M. Farinaccio, J. Aronson. 2019. Towards a Dryland Framework Species Approach. Research in progress in the Monte Austral of Argentina. J. Arid Environments 161:1-10. https://doi.org/10.1016/j.jaridenv.2018.09.001.

Pérez, D.R., C. Pilustrelli, F.M. Farinaccio, G. Sabino, J. Aronson. 2020. Evaluating success of various restorative interventions through drone- and field-collected data, using six putative framework species in Argentinian Patagonia. Restoration Ecology. 28:44-53. https:// doi: 10.1111/rec.13025.

SER (Society for Ecological Restoration International Science & Policy Working Group). 2004. The SER International Primer on Ecological Restoration.https://www.ser-rrc.org/resource/the-ser-international-primer-on/.

A foray in the Mojave Desert

Thibaud Aronson describes the botany, ecology, and degradation of southern California’s unique desert woodlands.

There are four deserts in North America – the Great Basin, Chihuahuan, Sonoran, and the Mojave. Both the Great Basin and the Chihuahuan deserts can have bitterly cold winters, and as a result their vegetation is quite stunted compared to the other two, with precious few trees. A few years ago, my father and I spent a fair amount of time in the Sonoran desert, both in Arizona and in Baja California, documenting its remarkable trees.

To fill an important gap in our survey of desert trees of the world, I recently visited the Mojave desert, home to one of the most iconic desert trees on the continent. Indeed, just about every time one mentions desert trees, at least in the US, the most common response is: “Oh, like Joshua trees?” Like Joshua trees, indeed.

The iconic Joshua tree (Yucca brevifolia) in the national park that bears its name in southern California’s Mojave desert.

As is typical in California, very different landscapes succeed each other in a relatively small area. So, over a week and surprisingly small distances, I traveled the region to get a sense of its rich tapestry of habitats  (see my itinerary).

Heading east from LAX Airport, I drove up a winding road into the San Gabriel Mountains. By the time I reached 2000 meters (6500 feet), I was completely surrounded by tall, dense forests comprising six or seven intermingled conifer species, and a number of ski resorts, deserted in the summer season. At my campsite that night, the temperature dropped to just a hair above freezing, quite a contrast from the stifling August heat I’d experienced that very morning!

The next day, I followed the spine of the mountains through the San Gabriels and on to the San Bernardinos. Driving along the glittering blue waters of Big Bear Lake, I went past “Starvation Flats Road”, a warning of what lay ahead. And indeed, I soon reached the eastern slopes, which gave me a striking view of the Mojave desert below – stark yellow plains that disappeared in the haze. Making my way down, the conifers began to thin out, and soon the first Joshua trees began to appear, some of them nearly as tall as the oaks they grew with.

On the eastern foothills of the San Bernardino mountains, Joshua trees grow together with Valley oaks (Quercus lobata) and California Black oaks (Q. kelloggii).

Turning back to look at where I had come from, I could see Old Greyback, the tallest summit in southern California. Then I headed southeast, hugging the base of the mountains, to the famous town of Palm Springs. Originally the town was named for the freshwater springs that flow down from the mountains and the California Palms (Washingtonia filifera) that grow along the canyons. Today the palms line every street in town, towering above the low buildings.

The skinny, carefully trimmed palms that define the look of Palm Springs are in fact unnatural, as wild fan palms develop thick skirts from their dead leaves that can extend almost all the way down to the ground. See below.

The landscape to the east of town is desolate, highlighting how precious and unusual the springs are. Creosote shrubs, their leaves a characteristic greyish yellowish, grow on the dusty flats as the incessant wind spins the thousands of turbines of the San Gorgonio Pass wind farm (the third largest in the state). Suddenly, a green ribbon appeared in the distance, and as I got closer, it resolved itself into a copse of large cottonwood trees, towering over an incredibly thick mesquite thicket. This is Big Morongo Canyon, the largest freshwater spring in the region.

The thick canopy of cottonwoods (Populus fremontii) at Big Morongo canyon.

As soon as I stepped under the trees, it was clear that I had entered an oasis of life: orioles, goldfinches and hummingbirds flitted in the undergrowth, while jays pestered a great horned owl that they had found perched in a cottonwood. Cottontail rabbits hopped on the path ahead of me, and a coachwhip (Masticophis flagellum) rattled its tail at me, this tiny, harmless snake attempting (as many other local snakes do) to look like a rattlesnake to scare off potential predators.

A female Anna’s hummingbird (Calypte anna) and some bees drinking at Big Morongo.

Before it got too hot, I continued on my way farther east, until I reached Yucca Valley, and from there Joshua Tree National Park. It is a surreal experience, as they appear almost out of nowhere, the phantasmagorical silhouettes of these giant tree Yuccas stretching to the horizon, the unique bluish grey tinge of their leaves giving a peculiar appearance to the air itself. It is a landscape quite unlike any I had ever seen. Though it is hard to understand how the first pilgrims decided that one of these trees was the prophet Joshua, pointing them in the direction of the promised land, as each tree seems to point a different way!

Right on the edge of the national park, a Greater Roadrunner (Geococcyx californianus) looks for its next prey perched in a Joshua Tree.

While the northern parts of the Mojave are low-lying, making up the famously inhospitable Death Valley, Joshua Tree National Park sits at the southern edge of the desert, on a plateau about 1200 meters (4000 ft) above sea level. The cooler temperatures at that altitude are what allow the Yuccas to thrive, in truly remarkable numbers.

A typical scene from the northern section of the park. I couldn’t find any data on this, but there must be tens, if not hundreds of thousands of Joshua Trees in the park.

While Joshua trees are the most distinctive – and seemingly the hardiest, growing even in the most exposed flats – they are not the only trees of the park. Many sandy desert washes cross the plateau, and along each of them grow various dicot trees. Most noticeable among these is Chilopsis linearis, in the Bignonia family. In the vernacular, it is known as ‘Desert willow’ because of its unusually long, narrow leaves and the fact that it grows in riparian habitats. Another tree found in the Mojave is the Papilionoid legume Psorothamnus spinosus, known as ‘Smoke tree’, as its pale grey leaves look like a cloudy puff of ashes, brightened in  summer when the trees are covered with gorgeous indigo-tinted, pea-like, flowers.

Smoke trees in the aptly-named Smoke Tree Wash, inside the Joshua Tree National Park.

Finally, there are two species of the legume tree Palo Verde (Parkinsonia), one of which I found providing shelter for a desert bighorn one evening near my campsite.

A young desert bighorn sheep (Ovis canadensis nelsoni). Bighorn populations have recovered quite well in recent decades, though they are still facing various threats in the California deserts. There are fewer than 300 found in Joshua Tree National Park (ca. 800,000 acres, or 3,200 km² in size).

Furthermore, the park is known for its elaborate formations of basaltic rock, which add to the surreal beauty of the landscape, and attract rock-climbers from all over the world. These rock piles, with the shelter and extra moisture that they provide, also allow oaks, pinyon pines, and junipers (all trees that typically grow on the higher mountain slopes) to survive down on the plateau as well.

At Hidden Valley, in the central section of the park, large pinyon pines (Pinus monophylla) grow among the basalt rock piles.

There are also several fan palm oases in the park, from Fortynine Palms, standing on its own amid the bare rocky slopes, reminding me of the mountains of northern Oman, to the glorious Cottonwood Springs, where massive cottonwoods barely top over the enormous palm trees, who formed a dense cluster sheltering a family of barn owls.

The saddest fan palm oasis is undoubtedly Mara, also known as Twentynine Palms. It is said that the Serrano Indians who used to live in the area planted one palm tree for each son that was born to the tribe after they first settled there. Last year, a criminal fire swept through the area, killing several of the palm trees. Some blackened trunks still stand, while several others had to be completely cut down. All in all, it is a sadly apt metaphor for what has befallen these first nations of indigenous people who called the area home for centuries prior to the arrival of Europeans.

Compare the glorious Cottonwood spring, protected as it is in a remote part of the national park, with the sad oasis of Mara, still showing the scars from last year’s fire that was set by an arsonist.

From there, I drove south through the park, and the landscape began to change markedly, as this is the where the Mojave gives way to the Sonoran desert. It got warmer and drier as the elevation decreased. The Joshua trees disappeared, replaced by ocotillos and in some areas, fields of teddybear cholla cacti (Cylindropuntia bigelovii). Passing through spectacular layers of exposed rock, I reached the Bajada, a grassy savanna with large ironwood trees (Olneya tesota, also a tree legume) a scene more akin to an African savanna than the landscapes I had left behind that same morning! This was quite striking as we had found ironwood trees to be much scarcer in Baja California!

From there, it was only a short way to the final stop on my trip: the Salton Sea. Lying about 70 meters below sea level, this is actually a depression, which was periodically filled by exceptional flooding on the Colorado River. The last time this happened was in 1905. Since it has no outlet, the lake progressively becomes more saline and eventually evaporates, until the Colorado floods its banks and fills it again.

Furthermore, because of repeated Colorado River floods, the surrounding soils are very fertile, despite the extremely dry climate. As a result, in the early 20th century, at the height of the hubris that characterized the development of the American Southwest, massive irrigation projects were put in place in the Coachella and Imperial valleys, at the northern and southern ends of the Salton Sea, respectively. The latter – formerly called Valley of Death, was rebranded as Imperial Valley – in a remarkable feat of marketing well described by Fred Pierce in When the Rivers Run Dry (2006). Today, the landscape as seen from the sky is surreal: the deep blue waters contrasting with the yellow of the surrounding desert, while the valleys at both ends are an incongruous green. The perfectly rectangular fields stretch all the way to the Mexican border, for a combined irrigated area equal to nearly three times that of the Salton Sea itself! These fields produce a large portion of the state’s lettuce, broccoli, carrots, and especially alfalfa, to feed California’s behemoth dairy industry. The sight of the hundreds of sprinklers going full tilt in the midday heat, to water alfalfa that could be grown in the East for a fraction of the cost, was rather off-putting, to say the least. (For a comprehensive and depressing history of water usage in the American West, read Cadillac Desert (1986), by Mark Reisner).

Irrigated vineyards in the southern end of the Coachella Valley. Note the extremely arid ranges in the distance, which stretch between Joshua Tree National Park and the Salton Sea.

As is by now well known, the Colorado has been well and truly “tamed”, its once wild run dammed in fifteen places, and every ounce of its water used to irrigate the thirsty cities and fields of the West, so that hardly a drop reaches its once mighty delta. In other words, the Salton Sea may soon be gone for good. And what else can we look forward to?

In a nutshell, the whole area is a mess. For a century, agricultural runoff has ended up in the Salton Sea itself and now, as the Sea is shrinking, more and more of its bed is being exposed and sediments heavily contaminated with salt and pesticides are being picked up by the winds. This is a massive public health issue. Not to mention the ecological disaster as the waters become too saline to support the fish that dwell in it, depriving the millions of birds that pass through the area of some of the only food available on that portion of the migration flyway. Furthermore, the well-publicized water shortages and catastrophic wildfires of California get worse with every passing year.

Obviously, agriculture in southern California will continue, but in what fashion? According to the California Department of Agriculture, more than half of the irrigated cropland in the state is badly affected by salinization. Surely this should be a wake-up call to explore alternative futures. For one thing, as Richard Felger, doyen of US-based Sonoran desert botanists and explorers, puts it, we need to learn to “Fit the crop to the land, not the land to the crop.”

Even though desert organisms are tremendously well-adapted to the harsh conditions they face on a daily basis, even they can only take so much. According to a recent study, rising temperatures are rapidly making the national park unsuitable for Joshua Trees themselves. In the best-case scenario, major efforts to reduce greenhouse gas emissions could save around 20% of suitable habitat for Joshua trees within the park after the year 2070. In the worst case, with no reduction in carbon emissions, 50 years from now,  the Joshua Tree National park will retain a mere 0.02 percent of its Joshua tree habitat.

The first white explorers who saw the Western deserts of North America thought them so hostile that they could never support settlement, disregarding the Native Americans and the wealth of fauna and flora who had long been living in the desert, in a very delicate balance. But in the frenzy of the twentieth century, through truly prodigious amounts of effort, descendants of the European colonists radically reshaped these landscapes to suit their needs with very little understanding of the long-term consequences of their actions. The entire enterprise is clearly and dangerously unsustainable, as water reserves that accumulated over hundreds of thousands of years were drained in just a few decades.

We often hear about the fight against desertification, which is conflated with some sort of fight against advancing deserts. But it is important to remember that deserts, while harsh, can still be beautiful and full of vibrant and unique life. Joshua Tree National Park, the Mojave National Preserve, and a few other protected areas give us a glimpse into what once was. But they are mere handkerchiefs. If the region is to have a chance at a sustainable future, we need new paradigms, new laws based on a much better understanding of how life can balance itself in arid lands. Based on that understanding, it is imperative that we move away from the pattern of careless exploitation and transformation, stretching farther and farther away from what these deserts once were. Instead, it is past time to commit to ecological restoration and allied activities for the Mojave and indeed all degraded and mis-used deserts and semi-deserts, especially as climate chaos unfolds.

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 21^st century, we used information already online in another Tropicos project, the Catalogue of the Flora of Madagascar as well as many other online sources.

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.

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

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.

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.

 

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.

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.

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.

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

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.

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.

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 29^th 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.

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.

Virtual field trip to the Guajira desert and the Serranía de Macuira in northern Colombia

James and Thibaud Aronson describe the natural and cultural context of a little-known area of northern Colombia, home to the Wayuu people and a microcosm of arid lands worldwide.

Colombia is one of the world’s seventeen megadiverse countries.  In a few hours of travel, one can go from the sweltering Amazonian lowlands to the snow-capped peaks of the Andes. It even has a true desert, a small peninsula called la Guajira, shared with Venezuela, which constitutes the northernmost point of South America.

For most of the last 50 years, the Guajira was notoriously dangerous, principally because of drug trafficking, but things have improved in recent years. We traveled there last month, shortly after the first big rains the region had received in several years. ​ And we found that it’s a poignant example of the plight of drylands globally and their peoples.

The Guajira peninsula, in northern Colombia, including the authors’ itinerary.

Our trip actually began in Panama, which was part of Colombia until 1903. While much smaller, Panama is also a country of contrasts. Much of the Pacific coast used to be covered in seasonally dry tropical forest, and some fragments persist today in and around Panama City itself, while the forests of the Caribbean slope, a mere 50 km away, are much wetter. A curious switch occurs near the Colombian border, where the wet forests then extend down the Pacific coast of Colombia and Ecuador – the famous Chocó-Darien rainforest, one of the wettest and most diverse tropical forests on Earth.

Meanwhile, the seasonally dry forests continue along the 1,000 km long Caribbean coast of Colombia and give way to semi-desert and then true desert (annual rainfall < 250 mm), lined by a coast with mangrove forests, and a series of lagoons and bays where flamingos and ibises add a shock of color.

Mangroves in Bahia Hundita, Alta Guajira, showing desert woodland with tree cacti (Stenocereus griseus) and various legume trees growing on the sandstone bluffs in the background.

Roseate spoonbills, great egrets, and a white ibis sharing a coastal wetland near Uribia.

As if this wasn’t enough contrast, halfway along the Caribbean coast rises the Sierra Nevada de Santa Marta, Colombia’s tallest mountain range, reaching 5,700 meters (18,700 feet) above sea level at the highest peak. It takes only about two hours to drive from its foothills, where toucans and monkeys chatter in the majestic trees, to Riohacha, the gateway to the desert.

A brown-throated three-toed sloth (Bradypus variegatus) hanging by one arm in a Cecropia tree in Tayrona National Park, at the base of the Santa Marta mountains.

Alta Guajira’s desert trees and woodlands

The Alta Guajira is arid indeed, but it hosts trees, remarkable both in their exuberant diversity and their abundance, considering the high temperatures and meager rainfall. We saw what we consider true desert canopies, such as we have described in other posts. However, no desert flora exists in isolation, and indeed the kinship to the ecosystem type known as Seasonal Dry Tropical Forest (SDTF; see map above) seems to be strong.

The dominant trees of the Guajira are species of Prosopis, Caesalpinia, Vachellia (formerly part of Acacia s.l.), Parkinsonia and other legume genera, accompanied by Bursera, Capparis relatives, Bignoniaceae, and other species common in the dry forests of Central and South America, and 3 kinds of tree cacti (Stenocereus, Pilocereus, and Pereskia), growing close together, often covered in climbing vines. In particular, it was interesting to see bona fide desert woodlands dominated by two well-known legume trees, Prosopis juliflora and Vachellia farnesiana, which are widespread and often strongly invasive in other parts of the world, but not here! Fascinating biogeographical and ecological questions abound in this poorly explored region, many of which are relevant to conservation and restoration.

Regarding  landscape ecology in the region, the vegetation is curiously like a patchwork, alternating between dense desert woodlands, nearly pure tree cacti stands, sometimes with a dense grass cover, and sometimes not, and frequent saline flats where nothing grows. In our opinion, the human element, namely land and resource use history, is paramount to understanding what one sees when travelling here and trying to ‘read’ the landscapes.

Mixed patch of tree cacti and spiny legume trees with a surprising amount of grass understory. Elsewhere under similar stands, for no clear reason, there is no grass cover at all.

A track of the Alta Guajira, near Nazareth, at the base of the Macuira hills where the notorious Prosopis juliflora, known in Colombia as Trupillo, is so exuberant and long-lived it forms a natural tunnel above this track.

Prosopis juliflora colonizes newly exposed beach dunes, in areas where the shoreline is receding. Here, at Camarones, it occurs alongside Calotropis procera, a woody weed of the Apocynaceae known in English as giant milkweed, and familiar throughout the Caribbean islands, the Middle East and drylands of Africa. It survives because of its toxic milky latex where most other plants get eaten out by livestock.

Other standouts are the beautiful Palo de Brasil, Haematoxylum brasiletto, with its unusual fluted trunks and Pereskia guamacho, an enigmatic ‘primitive’ tree cactus with true leaves and one of the most exquisite tasting fruits we know. This is one of the least well-known but most intriguing of all desert trees to our minds.

Typical landscape of the northern Guajira desert woodlands, with an even-aged stand of one of the several neotropical legume trees known as Brazilwood: Haematoxylum brasiletto, or Palo de Brasil in Spanish.

Despite those common names, this species is in fact only found wild along Caribbean coastlines from Colombia and Venezeula, all the way north to both coasts of Mexico. The scientific name is thus a misnomer. The most famous Brazilwood tree is another legume, Paubrasilia echinata (= Caesalpinia echinata) that once grew abundantly along the Atlantic coast of Brazil, as a large tree with a massive trunk, reaching up to 15 meters tall. Today, it’s almost entirely gone in the wild, and mostly planted in gardens and along roadsides. It was prized for the bright red dye obtained from the resin that oozes from cut branches or trunks. The dye was widely used by textile weavers in the Americas and Europe in the 17^th-19^th centuries. The tree also provided the wood of choice for high quality bows for stringed instruments and was widely used for furniture making as well. So important was its economic value that the country was named after it, originally Terra do Brasil (Land of the Brazilwood), later shortened to Brazil. Recently it was designated as sole member of a new genus, as part of a comprehensive revision of the entire genus Caesalpinia, carried out by an international team of experts.

It’s curious that H. brasiletto bears the same common name as P. echinata, since the two trees are nothing alike, apart from their red sap and heartwood. Little literature exists for H. brasiletto, and we are embarking on some detective work to shed some light on this puzzle. We go into detail as these are both relatively fast-growing trees with great economic as well as ecological value. They would both be excellent candidates for inclusion in ecological restoration work and are both in dire need of conservation efforts.

Wayuu: Alta Guajira’s Indigenous People

This desert also hosts a fairly large human population. The Guajira is the home of the Wayuu, Colombia’s largest surviving Indigenous group and, along with the Navajo, one of the last desert-dwelling peoples in the New World. These fiercely independent people, organized in 17 matrilineal clans, were never subjugated by the Spanish, and even today the Guajira region functions mostly in isolation from the rest of the country. As we were heading well off the beaten track, we needed a guide, a 4 x 4 jeep in good condition, and a skilled driver to navigate the meandering and unmarked desert paths.

Despite an ancient history of human presence, and some periods of intensive exploitation and intervention (such as a pearl harvesting boom that took place soon after European explorers arrived), the ecological condition of the region at the landscape scale is remarkably good. Indeed, apart from the salt works in the small town of Manaure, which produce two thirds of Colombia’s salt, and El Cerrejón, South America’s largest open-pit coal mine, in the south of the Guajira, there is no major industry.

Typical traditional salt works at Manaure worked by hand by local men and women just as they have for generations.

And the isolated people who dwell here – fishermen, shepherds, and weavers – are right out of a Gabriel García Márquez story. Indeed the author, most famous for One Hundred Years of Solitude, grew up on Colombia’s northern coast, speaking both Spanish and the Wayuu language, Wayuunaiki. As we traveled deeper into the desert, we traversed small settlements with simple houses made of wood and yards surrounded by tree cacti hedges.

The Wayuu village of Boca de Camarones, in the south of the Guajira peninsula, showing the living hedgerows of columnar cacti produced from tall stanchions. In the background, surrounding the homes, are Trupillos, and good specimens of Dividivi Libidibia coriaria (formerly called Caesalpinia coriaria).

This third caesalpinoid legume tree, closely related to the two Brazilwoods mentioned above, is the source of another lovely red dye, derived in this case from its pods. Until recently, there was an annual festival in Camarones, in honor of this formerly major economic plant product. The tree was also used as an important source of tannins. Like Paubrasilia echinata, it deserves more ethnobotanical and biogeographical studies.

Here, as in many other arid lands, goats and sheep are important for the Wayuu people, as a source of food and social currency. For example bride price during arranged weddings, and gifts for guests attending vigils of important elders and healers, are paid to this day in heads of live goats or sheep. Historically, mules and donkeys were very common as well, but now they are increasingly replaced by motorcycles.

Small children following a flock of desert-hardy sheep in Boca de Camarones. The peaks of the Sierra Nevada de Santa Marta are visible in the background.

Crown jewel of the Alta Guajira

The crown jewel of this desert, its best kept secret, is the Serranía de la Macuira, a small mountain range (serranía meaning “small sierra” in Spanish) in the northeast of the peninsula. This miniature sky island is almost impossibly lush, thanks to moisture-bearing clouds that shroud its upper reaches. They feed streams that flow year-round, and sustain many kinds of trees that grow to well over 10 meters tall.

As one climbs the slopes of the Macuira, the humidity dramatically increases and the parched lowlands, with their desert woodlands, blend perceptibly into a seasonally dry tropical forest reminiscent of those we had seen in Panama. A little-known fact: seasonally dry tropical forests are the most endangered of all tropical forest types, and those in La Guajira are worthy of much greater research, conservation, and restoration.

Climbing higher still, the mid- and upper ranges of the Macuira seem like another world. Most astonishing of all, there is apparently an abrupt transition above 550 meters, and the higher reaches are covered in true cloud forest, with mosses, epiphytic orchids, tree ferns, and dozens of tree species that otherwise occur hundreds of kilometers away! This is probably the only place in the world where cloud forest is found less than 5 km from true desert. Fortunately – from a conservation point of view, but unfortunately for us – the upper peaks of all three peaks of the Macuira are sacred to the Wayuu, and completely off-limits, to native people and visitors alike. Try as we might, we were unable to get permission to hike up there.

Seasonally dry tropical forest on the northeastern facing slope of the Macuira, where precipitation is much higher than in the surrounding lowlands occupied by desert woodlands.

Even though the whole Macuira is officially protected as a national park, the reality is more complicated. While walking inside the park, we encountered recently cut trees, the ubiquitous goats, and even a Wayuu man hunting birds with a slingshot in broad daylight. The beautiful continuous tree canopy covering most of the slopes stands in stark contrast to the severely eroded, nearly bare hilltops, on which stand small Wayuu homesteads. Still, the presence of clear ecotones speaks to mostly healthy landscapes.

The severe erosion around a small Wayuu farm inside the Macuira National Park.

Alta Guajira’s ecological future

The pressures on the Guajira’s ecosystem health include a large mine (El Cerrejón, mentioned above), overgrazing by domestic livestock, and stark poverty facing the native people and more recent immigrants. But there are positive factors as well. There are progressive laws in Colombia related to ecological restoration. Moreover, since 2012, Colombia has a National Restoration and Rehabilitation Plan (pdf), as well as a Law of Remediation, which imposes large environmental offset payments from large-scale development projects (like hydroelectric dams) to underwrite conservation and restoration work. Moreover, the national park system, within its network of 56 protected areas, harbors populations of almost half of the 102 Indigenous peoples in the country, and in the case of Macuira, this is clearly not just a paper park idea.

Still, the national park (25,000 ha in size; officially designated in 1977), operates with a skeleton staff attempting to carry out an ambitious management plan (pdf) despite an insufficient budget. Staff and volunteers provide short tours to day-visitors, and maintain some fenced-off livestock exclosure plots, where they are studying natural regeneration. Daily interaction with the Wayuu living in the park appear to be harmonious, and indeed there is a clear sense that part of the Park’s mission is to restore and protect the Wayuu people’s natural and cultural heritage. Recently, the Instituto Humboldt, Colombia’s stellar national research institute, has established permanent plots in the Macuira range as part of a series of 17 plots including all the tropical dry forest types in Colombia. In the Macuira, this work is done in collaboration with botanists from the Universidad de Antioquia, in Medellin. Furthermore, researchers at Kew, the Smithsonian Institute, and many conservation NGOs are all developing collaborations with the Colombian government to explore and help the country move forward with green development.  The Missouri Botanical Garden also has long-standing MoUs for joint research with 3 different institutions in Colombia, with bright prospects for deepening cooperation in the future.

Like many Indigenous peoples around the world, the Wayuu are at a crossroads. Their language and some of their traditions are still alive and well, but others have already faded. There are few legal sources of income in the harsh desert, the ancestral Wayuu land. How will they manage in the future? What can they do to adapt?  Some, like our guide, José Luis, are trying to change mentalities, but they clearly need more help.  As throughout Colombia, there is clear and urgent need to build on the alpha-level studies already underway, and move onto applied ecology, agroforestry and land management programs, including community-based restoration programs and ecotourism in conjunction with the national parks.

Our Wayuu guide José Luis Pushaina Epiayu (on the right) and Macuira park ranger Ricardo Brito Baez-Uriana (on the left), talking about birds with a local Wayuu family.

South Africa 3 | Town and country: aiming for ecological restoration at the landscape scale

James and Thibaud Aronson offer their third photo essay from South Africa, highlighting FOSTER, a dramatically successful community-based restoration program in the Eastern Cape, aimed at eradicating an invasive Australian acacia, and reducing urban wildfire risk, and a private restoration program at Kaboega Farm, situated in a megadiverse landscape of extraordinary conservation and educational value.

The Republic of South Africa is rightly famous for its 22-year old Working for Water program, WfW, and offshoots such as Working for Wetlands. These government-funded programs aim at restoring both natural and social capital, which are clearly the wave and the way of the future. They are also increasingly working with NGO implementers, private companies, and landowners in the Karoo, as we highlighted in two earlier posts (here and here). Teams, partnerships, and networks are essential here, given the complexity of the landscapes – both biophysical and political.

To close our trip in South Africa, we traveled to Cape Saint Francis, on the coast of the Eastern Cape, where our friends Richard Cowling and Shirley Pierce, who have lived there for more than 20 years, long ago founded a restoration project they dubbed FOSTER (short for Friends of the St Francis Nature Areas).

Richard, a top academic, communicator, and world expert on the ecology, biodiversity, and landscapes of South Africa has also worked closely with the WfW government programs elsewhere in the country, not only in the fynbos (the mega-diverse shrublands of the mediterranean-type climate region of the Cape) but also the karoo and subtropical thicket (on which, more below).

Richard Cowling and Shirley Pierce-Cowling in their adopted habitat, St Francis Bay. 2013.  

In and around Cape St Francis, and St Francis Bay, one of the main issue is Acacia cyclops (known in South Africa as rooikrans), one of many fast-growing acacias intentionally introduced from Australia 150 years ago for sand dune stabilization.

In 1994, Richard and Shirley took up the challenge of developing a conservation plan and implementation strategy for consolidating 230 ha of municipal land and existing protected areas into a network that would sustain – among other things – faunal movement. More than 50% of this was densely invaded with rooikrans; only 38 ha was officially proclaimed a nature reserve. It was a slow process. Rooikrans grows quicker and taller than the native plants. But they had a very strong motivation. Indeed, “as a result of its greater biomass and more flammable foliage, rooikrans increases fire hazard by several fold relative to uninvaded fynbos” says Richard.

Over 20 years, they achieved near total success in removal of seed-bearing alien plants through the generous funding from the World Wide Fund (WWF) and residents’ donations, but only on the 132 hectares of public lands where they could work, often with the enthusiastic help of school groups and volunteers who learned much along the way.

FOSTER restoration workers conducting follow-up removal of the alien invasive rooikrans, Acacia cyclops, in the Cape St Francis nature reserve. Photo. R.M. Cowling.

A learner from a local school enjoying the leaves of Brunsvigia gregaria (Amaryllidaceae) during an excursion organized by FOSTER. Photo. R.M. Cowling.

 

 

Brunsvigia gregaria in bloom; this species is popularly known as candelabra flower.  Cape St Francis, Apr 7, 2016.

But there were hundreds of hectares more to clear, both on public and private lands around the town. Then, in late 2012, a fire swept through, leaving severe damage and a wake-up call.

By that time, WfW was ready to help with restoration on private lands, provided that landowners contributed to the effort. The help from WfW and others much expanded FOSTER’s reach, and in only four years, some 1000 hectares of rooikrans were cleared from private lands in the area.

This of course dramatically reduced the township’s vulnerability to wildfire damage. As proof, when another massive wildfire swept through the area in January 2016, only three houses were destroyed. Notably, all three belonged to owners who had refused access to WfW workers seeking to eradicate rooikrans.

Other communities along the coast have taken notice and hopefully will follow the example of Cape St Francis.

Second landscape example: Kaboega farm

Finally, following Richard’s advice we drove two hours inland from Port Elisabeth, not too far from St Francis Bay, to visit a truly remarkable place where four different ecosystem types meet and intermingle in a property of only 6550 hectares: 1) fynbos, 2) the karoo desert, here at its southernmost limit, 3) the northernmost temperate rain forest fragments of the South East, of which the only important remnants are found in the Knysna region, and 4) subtropical thickets.

Outenieqwa-geelhout, or small-leaved yellowwood, Podocarpus falcatus. Outstanding specimen of the relict population growing near a perennial stream at Kaboega Farm.

What South Africans call subtropical thickets are in fact a remarkable tapestry of vegetation types, with as many as 116 distinct variants (Cowling et al. 2005). Of particular interest here is the so-called spekboom-dominated thicket, characterized by the spekboom (Portulacaria afra).

Fully mature spekboom, one of the largest individuals known

Spekboom-dominated thicket once flourished on approximately 1.4 million hectares (3.46 million acres), but today it occupies barely one-seventh of its former area. “The remainder has been degraded by over-exploitation, mainly through injudicious farming with angora goats……” (see the report Investing in Sustainability). However, spekboom is an extremely hardy succulent tree, remarkably fast-growing and readily propagated from cuttings, or even large stancheons.

This makes it attractive for large-scale restoration work. Indeed, it has been the focus of much attention from Working for Woodlands, another member of the Working-for family of government restoration programs. The manager and co-owners of Kaboega Farm, Ian and Sandra Ritchie, stopped all agricultural activity on their land 20 years ago, to allow the land to recover from an estimated 135 years of over-grazing by small livestock. They live instead by hosting visitors, including succulent plant lovers, drawn to this hotspot of Haworthias, and university groups led by Richard Cowling. Among other recent discoveries, Cowling and co-workers have shown that subtle difference in community-level frost tolerance can determine the boundaries between tightly packed biomes at Kaboega, where diversity is sky-high despite an average rainfall of just 300 mm per annum and frequent, extreme droughts.

Spekboom cuttings struggling to get going

Furthermore, Ian and Sandra Ritchie are attempting to restore swathes of spekboom thicket at strategic spots on their farm, as a part of an ambitious large-scale program with support of Working for Woodlands.

They plant spekboom cuttings, which over time create an enhanced micro-environment in an otherwise harsh and difficult environment for young plants, and thus try to kick-start the regeneration of the habitat, biological community, and ecosystem. Furthermore, spekboom traps large amounts of CO₂, and the general hope is that carbon credits can help finance large-scale restoration in the future. In the meantime, this is a remarkably attractive destination for nature-lovers.  In addition to the flora and landscapes, giraffe, kudu, and other game are added and allowed to roam free for the pleasure of visitors (and the owners). When numbers grow too high, however, there is a risk of exceeding carrying capacity, and some animals are captured for resale to other land-owners. This provides an additional income flow as game ranching linked to tourism and recreational hunting is increasingly popular in the region.

Portion of a thriving population of 28 South African giraffe or Cape giraffe (Giraffa giraffa giraffa) at Kaboega Farm. While some argue that giraffes are not native to the area, nearby millennial cave paintings indicate the contrary.

At this remarkable farm, science-based conservation and restoration are making progress in an attempt to enhance biodiversity conservation, tourism revenues, and ecosystem services of all kinds. Clearly, spekboom planting is not an all-in-one solution; for jumpstarting restoration and assisting regeneration in a complex landscape and land tenure situation like this one, where temperate forests, fynbos, thicket, and karoo shrublands all occur and interact, a landscape perspective on the challenges of ecological restoration is essential. We’ll be posting more on this challenge in the future.

South Africa 1. Restoring natural and social capital in Namaqualand

James and Thibaud Aronson post the third of four photo essays on their recent field trip to Namibia and South Africa.

As soon as we crossed over the border from southern Namibia into northwestern South Africa, it was clear that we were looking at a whole different story. We were now in the driest part of South Africa and one of the most sparsely populated. Also, Namaqualand – a winter-rainfall desert of ca. 50,000 km² – is one of the biodiversity hotspots of the world. The area is well known to tourists for the few weeks in August-September (the southern winter), when hundreds of plant species, benefiting from the winter rains, put on an incredible floral display and tapestry of textures and colors, down below your ankles.

A rich community of toe-high succulents endemic to saline quartz patches . This photo was taken at Douse The Glim, not far south of Garies in southern Namaqualand. Many endemics of the Mesembs (Mesembryanthemaceae) occur here, including the sunken “Silver skin”, Argyroderma delaetii,  Cephalophyllum spissum, and “Redbeads”, Sarcocornia xerophila, a cousin of the cosmopolitan Salicornias. Identification of plants: Sue Milton and Richard Cowling, both of whom we will meet in the next blog post.

 

 

Argyroderma delaetii, a dwarf, sunken ‘silver skin’, of a genus restricted to the Western Cape, South Africa, in the Knersvlakte Nature Reserve . This photo was taken by Sue Milton in 2014, a much wetter year  than 2016.

All in all, apart from natural history buffs, botanists, and conservationists, not much attention is paid to this poor, rural area. In a nutshell, the rapidly exploitable resources that could be had – copper, timber, and the like – are now long gone. What is left is – to speak bluntly – a lot of poverty and a lot of land degradation. And a lot of biodiversity: indeed the Succulent Karoo region of Namaqualand and southern Namibia is one of the biodiversity hotspots of the world.

We met with some of the people making a difference there, working with South Africa’s most iconic environmental program, the Working for-family of government-funded programs, working together to restore natural capital and social capital at the same time.

Sheep grazing on  abandoned crop land in Namaqualand, near Leliefontein.

The Western Cape, South Africa has had a tradition of rather damaging sheep farming for centuries. But the country as a whole has also had a proud tradition of nature conservation for over a century, which is a lot more than most countries can boast.

However, what is  even rarer is that ecological restoration has been part of the national vocabulary for a generation. A game-changing initiative that moved the country to the next level was a government program launched in 1995, called Working for Water, or WfW.

South Africa was faced with two metaphorical birds. On the one hand, approximately half of its population lived (and unfortunately still does) in poverty. On the other, several invasive non-native tree species had taken over many of the country’s waterways, outcompeting native species, choking river beds, and draining the water tables.

Working for Water was the stone. Every year it hires some of the country’s poorest people –  38,000 in 2015 –  in rural areas in all nine provinces and employs them to remove those noxious woody species. Since its inception, the program has spent hundreds of millions of dollars and provided desirable jobs near home each year. The benefits to people are in fact multiple. Workers are provided with both an income and on-the-job training and capacity-building, with some going on to start their own companies, providing ecological restoration services to private landowners. They also acquire an esprit de corps  and pride in their achievements.

With the same ‘stone’, over 2 million hectares, mostly along water courses, have been cleared of invasive trees and water supply has been notably increased for the associated communities. Finally, the large amounts of timber and vegetable biomass harvested from the invasive trees are used to produce eco-furniture, which is then sold to help finance the program. Research is under way to find methods for producing biofuel from the woody weeds as well as to improve the ecological impact of the effort.

The small town of Garies, southern Namaqualand. The riverbed is completely dry, but there is enough moisture in the soil to support what may look like natural riparian vegetation. In fact, not a single tree is native. Instead they are Mesquites (Prosopis hybrids) from South America, Salt cedars (Tamarix hybrids), and Australian Wattles (Acacia karroo,  A. cyclops).

The Australian wattle (Acacia cyclops), one of the worst invasive trees in various habitat types in South Africa.

WfW now oversees over 300 projects across South Africa, and its success has led to the establishment by successive government administrations of several other programs, such as Working on Fire, Working for Wetlands, and Working for Woodlands. The goals are ambitious and together this ‘family’ of Working for- programs exemplifies the emerging understanding that ecological restoration can be a bridge-builder between long-term conservation efforts, and sustainable socio-economic development goals. At a time when protected areas are menaced worldwide by dubious government cop-outs on protected areas, South Africa is a refreshing exception that deserves praise and celebration.

Thanks to introductions set up by our friend Dr. Christo Marais, the number 2 man of WfW, we had a chance to talk to Ronnie Newman, Amanda Bourne, and Halycone Muller from Conservation South Africa (CSA), who work in Namaqualand on restoration projects, in close liaison with SAN Parks (the body that governs South African national parks), and through financing of Working for Wetlands.

From left to right, Amanda Bourne, Ronnie Newman, and Halcyone Muller at CSA offices in Springbok.

SAN Parks and CSA use funding from a new programme under WFW called Land User Incentive Programme, to hire people to restore degraded rangelands.  CSA and SAN Parks are thus implementing agents for Working for Wetlands in this arrangement, something new in the history of the Working for- programs. The focus of this trio here in Namaqualand is to repair erosion gullies, called “dongas” in southern Africa. These are very often a result of over-stocking and overgrazing by domestic livestock and get continually worse if left unattended. Thanks to this government-funded effort,  workers build beautiful gabions and other structures to slow water flowing downhill, catch sediments and eventually fill the gullies. Most of the gabions are made with metal baskets, or simply dry stones carefully assembled by skilled workers to make low but sturdy walls. However, in some cases, larger gabions are made out of concrete. As Amanda Bourne put it,  “this is about supporting the people who live and work on the land to restore and better manage it.  They are paid at a supplementary rate to undertake restoration on their own land, which will directly benefit their other (mostly agricultural but not only) activities.”

Working for Wetlands workers building a series of stone retaining walls, near Kamieskroon. In small rivulets like this one the metal baskets of typical gabions are not easy to use and are not deemed cost-effective.

A week later, in Cape Town, we met up with Christo Marais, and with Sarah Frazee, the head of CSA. She told us that they aim at working at critical spots upstream of water points of importance to local communities whose livelihoods are largely dependent on sheep grazing. CSA also provides veterinary services at no cost to participating farmers, and tries to persuade them to reduce their herds and flocks to avoid over-stocking, especially in drought years like the current one. As Sarah put it, 80% of the biodiversity in Namaqualand is associated with wetlands, which makes focusing on their restoration important from a conservation perspective. But, as more broadly throughout South Africa, public-private efforts like this one can effectively address biodiversity, water supply, land erosion, as well as poverty and related social issues at the same time.

From a classical economics perspective, however, ecological restoration work in arid lands is slow, and often hard to justify, since the value of the land for production purposes is so low. However, not just here in the Western Cape, but throughout South Africa, the multiple goals of the Working for- program are being pushed forward and steadily refined.

There has been frequent criticism of the programs and not without cause. In particular, monitoring has not been implemented as well as could have been hoped, though the program has continually improved since its inception, both scientifically and in terms of its impact on ecosystems and people. It will be a long battle to achieve all of its goals, but despite its flaws, it remains one of the absolute best examples worldwide of programs that combine restoration of social and natural capital.

Six months after the building of the stone walls near Lileifontein, complemented by brushpacking to help build up organic matter, things are looking pretty good.

We close with a mention of the fabled triple bottom line – the holy grail of progressive governments. How to achieve social, ecological, and economic benefits with a single program? Next steps in improving the work of the Working for- programs, according to  Christo Marais, should include: 1) still greater investments in education, capacity-building and outreach to bring all of South Africa’s society on board with the restoration movement, and 2) galvanizing private investment in restoration. The introduction of implementing agencies like SAN Parks and CSA should help with both.

In our next two blogposts, we will report on what some private landowners and three wonderful NGOs, including RENU KARROO and F.O.S.T.E.R. are doing in the Nama Karroo and Thickets biomes.

Namib 2: Large wild animals, fences and farming (with good news about education)

James and Thibaud Aronson post the second of four blogposts on their recent field trip to Namibia and South Africa.

Africa is famous for its megafauna. Most foreign visitors, who only ever see them on safaris inside protected areas, may think that Africa has managed something every other continent has failed at: a harmonious relationship between people and entire trophic chains including large animals. In fact, many if not most interactions between humans and large animals in Africa, just as elsewhere, are conflictual and complex. Nothing illustrates the problem better than fences.

A legacy of European agricultural practices, long fences have become ubiquitous in Africa. They primarily serve to delineate property, control the movements of livestock, and in some cases limit the spread of epidemic diseases such as foot-and-mouth disease and bovine TB, and their spread to and from wild animals such a wildebeest and lions.

A typical small livestock herd in the Pro-Namib.

There are also the other kind of fences, the ones around protected areas, which often serve as effective protection for wildlife.  However, there is no doubt that livestock and veterinary fences have had and still have severe impacts on wild animal populations.

In particular, large mammals tend to range widely in search of food or water. Fences severely restrict their movements, with dramatic effects on populations in drought years. And mammals aren’t the only ones affected: large birds such as bustards suffer lethal collisions with power lines and fences, and tortoises are sometimes killed by electric fences.

The amazingly camouflaged Rüppell’s bustard (Eupodotis rueppellii), which is endemic to the Namib. Like other members of the bustard family, it occasionally collides with fences.

In Windhoek, we met with Dr. Chris Brown, chairperson of the Greater Fish River Canyon Landscape (GFRCL), a mosaic of diverse properties, from private reserves to working cattle farms united in an association, whose working motto is “What can we do better together?” It is one of five such associations in Namibia today that are part of the NAM-PLACE project, started by the Ministry of Environment and Tourism, and now supported by the United Nations Development Program.

Dr. Brown is also a director in a Namibian company, Gondwana Collection.  Chris told us “We have a triple bottom line approach to business, with both environment and social investment playing central roles.” The strategy is to buy land in marginal, overworked farming areas, “re-wild it” by taking off the livestock and taking down the fences, and then reintroduce indigenous mammals and reinforce populations that have dwindled. Next, they build lodges to attract medium- and high-end tourists interested in seeing wild nature. Their largest property to date – among 14 throughout the country – is a private, protected area of 130,000 ha on the east side of the Fish River Canyon, which is the largest canyon in Africa.

The Fish River canyon. The river only flows like this after heavy rains.

An Aloe dichotoma (Kokerboom in Afrikaans, or Quiver tree), one of the few trees in the southern Namib. In the past, Bushmen fashioned quivers for their arrows from the soft branches, hence the tree’s common name.

We were fortunate enough to spend two nights at one GFRCL partner’s lodge, a 40,000 ha reserve on the western rim of the canyon. This remarkable landscape has been inhabited by humans for millennia, as illustrated by the tools and rock engravings still found throughout, but ill-adapted sheep farming, along with the eradication of many species by white settlers over the last 150 years, had a massive impact on the landscape, which is only now beginning to heal.

‘Pecked’ rock engraving and associated stone tools near the Fish River Lodge.

Through Chris Brown, we also met Nils Odendaal, CEO of the NamibRand Nature Reserve, which is part of the Greater Sossusvlei-Namib Landscape, another of the five current NAM-PLACE projects. Nils was upbeat, citing serious prospects for addressing conservation and human well-being issues simultaneously. This group focuses on the Pro-Namib, the transition zone between the arid Namib and the more mesic escarpments to the East. Much of the land there was given to white South Africans after World War II as a reward for fighting in the war and for voting for the South African National Party. However, after two generations of unsustainable sheep grazing on these already nutrient- and moisture-poor lands, the area became known as the ‘bankruptcy belt’, when farms began to fail one after the other in the 1970s and 1980s. In 1982, a Namibian businessman bought up a large tract of land and made it into a nature reserve. From this initiative, NamibRand has expanded and now includes 202,000 ha, comprising several properties linked by a common constitution that stipulates, among other things, the removal of internal fences. High-quality, low-impact tourism at ‘ecolodges’ built on concessions inside the reserve provide part of the funds for its conservation activities and “sustainable utilization of its resources”.

A typical NamibRand landscape. Like most of the country, it has suffered a 4-year drought, which may now finally be breaking.

During our journey, we were able to stay one night at the flagship ecolodge, whose revenues help support an environmental education and sustainable living center called NaDeet (Namib Desert Environmental Education Trust), which aims to contribute to the hugely important task of teaching and capacity-building.

The pro-Namib is of critical importance for animals moving out of the Namib proper during droughts. Therefore the reserve is working on an agreement to take down part of its fences on its border with the massive Namib-Naukluft National Park, allowing mammals such as gemsbok to reach the highlands in times of drought.

The gemsbok (Oryx gazella), is perhaps the most characteristic large mammal of the southern Namib, and one of the most supremely adapted ungulates to desert living. Despite the drought, about 2000 of them thrive on the reserve.

In sum, these are two remarkable initiatives in two of the driest parts of Namibia. Both focus on large wild animals and high-end tourism. Neither has any direct support from the government, and they both are in difficult, arid lands. On the other hand, the very low human populations limit the potential for social conflict so common around conservation areas elsewhere in Africa.

Unquestionably, one major priority for Namibia is more and better environmental education, in classrooms and, above all, outdoors. Both GFRCL and NamibRand undertake detailed monitoring of the wild animals for which they are the stewards and defenders. They are also stellar communicators for wildlife and nature conservation through all their activities and presence on the internet. But what about training in the science and practice of ecological restoration?

As mentioned in our previous post, we were able to visit the Gobabeb Research and Training Center, in the central Namib, as we noted in our previous post. This Center has been operating continuously for over 50 years, and has produced a large body of research on many facets of the Namib, including hydrology, geology, paleohistory and of course ecology. Since 2012, it houses the NEMRU (Namib Ecological Restoration and Monitoring Unit), headed by Dr. Theo Wassenaar. This group has been doing research on restoration of arid lands in the country and training Namibian students, and lobbying for more research and training in restoration ecology at various universities in the country as well. The Gobabeb Training and Research Internship Programme (GTRIP) a five-month field course now in its seventh year. It is intended for young Namibian scientists interested in the fields of conservation, land and ecosystem management and ecological restoration. Under the guidance of researchers and staff, students have the opportunity to design and implement independent research projects that should “contribute to Namibia’s ability to manage and restore degraded ecosystems”. Posts from the GTRIP 2016 trainees are well worth looking at. Hopefully, this generation of Namibians will be the one to make the difference.

One obvious source of inspiration should be its neighbor, South Africa, which has been doing world-class restoration for over two decades. We spent three weeks on the other side of the border, meeting some of the key people and visiting cutting-edge restoration projects, as we’ll discuss and illustrate in our next two posts.

This year’s GTRIP students at the Gobabeb Research and Training Centre : Mathias Mwaetako, Fransiska Otto, Ailla-Tessa Iiyambula, and Kauna Kapitango, taken on the dunes south of the Kuiseb River. 15 February, 2016. Photo: Meg Schmitt.

Notes from the Namib 1. An ancient desert in transition

James and Thibaud Aronson post the first of four blogposts on their recent trip to Namibia and South Africa.

For the last trip for our book project on desert trees and restoration in arid regions, we started in Namibia, the only country in the world named after its desert! The Namib desert covers the entire coast of Namibia; it is more than 1500 km long and up to 200 km wide and extends north into Angola and south to South Africa. It is often said to be the oldest desert of the world, estimated by some to have continuously experienced arid or semi-arid conditions for the last 55- 80 million years. Certainly there is good evidence that it has been dry since the mid Miocene (11-16 million years ago). (The Atacama desert, from which we wrote last October, is also very old.  For comparison, the Sahara is less than than 7 million years old, and has experienced several much wetter periods since, some as recent as 10,000 years ago.

Some of the highest dunes in Africa are found at Sossusvlei, in central Namibia. The highest one, ‘Big Daddy’, is just a bit taller than the Eiffel Tower, reaching 325 meters.

The Namib is an exceptionally dry part of the Earth, with the coastal sections hardly receiving any rainfall at all. It does however receive coastal fogs, often for more than 100 days per year, which provide a significant source of moisture. Furthermore, the desert is traversed by 12 ephemeral rivers, which form striking linear oases, with lush riparian canopies. These canopies are dominated in most cases by very large Faidherbia albida trees, that remarkable tree known, among many other names, as Ana tree in southern Africa, and Gao in the Sahel.

Ana trees along the bed of the ephemeral Kuiseb river, central Namibia.

This tree – which until recently was classified as an Acacia, often shows a very unusual ‘reverse’ phenology compared to most woody plants in seasonally dry areas, as it keeps its leaves during the dry season and drops them in the wet season, when all the other deciduous trees and shrubs are growing new ones. Furthermore, its leaves as well as its pods – which it produces in copious numbers – are highly palatable to animals and high in protein. It is therefore an essential resource both for wild browsers and livestock. And there’s the shade it provides as well, which is a hugely important feature in all desert landscapes. In fact, Ana is one of the most important trees for herders throughout the continent, and is one of the few trees they deem more useful to them standing than cut down. As for the wildlife, these riparian canopies and the food they provide are very important. In fact, they enable some large mammal species, such as the kudu (Tragelaphus strepsiceros), and even rhinoceros and giraffe in the northern Namib, to range into a desert otherwise too harsh to support them.

A springbok (Antidorcas marsupialis) in the shade of giant Ana trees on the banks of the Kuiseb River. This animal is well-known for its pronking behavior: individuals like this can jump up to two meters straight into the air as a display of fitness to discourage predators from giving chase.

Unusual among deserts, and likely because of its age, the Namib is home to a large number of endemic animal species, mainly beetles, reptiles – such as the Wedge-snouted Sand Lizard (Meroles cuneirostris), and birds, including the Dune Lark (Calendulauda erythrochlamys), Namibia’s only endemic bird.

The Wedge-snouted Sand Lizard. The shape of its nose is not just a funny accident of evolution: it actually allows this lizard to ‘dive’ into the sand to escape its predators. This lizard is also known to perform a ‘thermal dance’, lifting one foot at a time, or lie on its stomach with all four feet in the air, to reduce its contact with the sand that can reach a scorching 70 degrees C (158 F)!

 

A Dune Lark, in the Namib-Rand Nature Reserve, in the process of building its nest in a hummock of grass. Its name is misleading; this bird actually prefers to live in the swale of vegetated dunes where its cryptic coloring makes it seemingly vanish as soon as you blink.

However, the Namib’s most famous endemic is undoubtedly Namibia’s national plant, the bizarre Welwitschia mirabilis. This is the sole species of the one genus in the venerable – dare we say inimitable? – Welwitschiaceae. This ‘monster’ is the only living member of a lineage more than 100 million years old. At a distance in certain lights you’d think it’s a beached giant squid…. but in fact it’s an ‘underground tree that can live well over a thousand years. Welwitschia is a near-endemic in Namibia as it occurs in southern Angola as well, but its entire geographic range is limited to the Namib Desert.

Female adult Welwitschia in its habitat. Note how the ends of the leaves dry out over time.

According to Dr. Theo Wassenaar, researcher at the 54-year old Gobabeb Research and Training Centre, this remarkable plant survives for centuries in a hyper arid desert by finding pockets of slightly moist soil in rock fissures. Having excavated more than two dozen plants, and examined their root systems in detail, he says “essentially it appears as if they forage for water, using their roots as scouts and sending in the troops (fine roots) when they find a pocket of moisture. And the differences in moisture can be slight, a few percent at most.”

An additional anomaly is that, although it is very hard to tell at first glance, each plant only has two leaves, gradually torn to tatters by the desert winds and sun. These two gigantic leaves never stop growing during the tree’s lifetime. It also is under threat, sad to say, as we will describe briefly a bit later.

Adult male Welwitschia in flower.

We traveled through nearly half of Namibia, from Walvis Bay in the center of the country, south to the Orange River on the South African border. And it is a breath-taking drive, because of the geology of this truly ancient desert, and the fact that the area has low population density, and still reasonably healthy ecosystems (except for the livestock fences galore) and large amounts of wildlife.

This state of affairs partly traces back to an inspired Nature Conservation Ordinance promulgated by the government back in 1975, which gave landowners property rights over the game animals on their land, within certain enlightened limits. Before that date, all wild animals, and all profits derived from them, went back to the state. Transferring ownership and the associated profits – from game viewing, trophy-hunting, and meat – to the landowners changed their perspective of wild animals. No longer competitors and predators of their livestock, to be kept out or exterminated, wild mammals became a source of revenue to be ‘cultivated’ and protected. As a result, the populations of large mammal species have seen impressive increases in the country. However, in some cases, this commercial incentive has led to some serious mismanagement. Indeed, some landowners have taken the view there is no such thing as too much game, and some private game farms maintain populations at unsustainably high densities in relatively small areas. Ironically, this can lead to some of the worst cases of overgrazing in the country!

Overall, the good health and integrity of the country’s ecosystems is a fantastic asset, of tremendous value for the nation. And – on paper, at least – the situation is admirable, with nearly 20% of the country in protected areas; since 2011, the entire coastline is protected inside three national parks, something no other country in the world can boast.

Still, the Namib desert and its fauna and flora face various threats, with dams affecting the hydrology of several ephemeral rivers, and a powerful and growing mining sector. In particular, the Welwitschia plains, where the largest southern population occurs, sit on top of a large uranium deposit. Efforts have been made to preserve the Welwitschia populations, and so far only two mines have been operating. But a third is currently being developed, which will be one of the world’s largest, and several other mining licenses may well be awarded if the price of uranium goes up again.

However the relationship of mining to restoration, and the role of the mining sector, are complex here as everywhere. As Dr Gabi Schneider, of the Namibian Uranium Institute told us, uranium mining is very localised, and the mine ‘footprints’ therefore are limited. Mining companies in Namibia have contributed in no small way to advancing the technology and science of arid land rehabilitation in the Namib, and also to research. Among other things they co-fund the Namib Ecological Restoration and Monitoring Unit program at Gobabeb. Uranium activities are governed by a Strategic Environmental Management Plan as well.

Furthermore, feral horses from abandoned tourism initiatives also roam the desert and eat Welwitschia leaves much more aggressively than native browsers do. Theo Wassenaar is working on this, and negotiating with local communities; it is a slow process but the Ministry of Environment and Tourism is also now engaging rural communities on this issue.

Horse-browsed Welwitschia in Welwitschia wash, near Gobabeb. Photo: Meg Schmitt, Gobabeb Research and Training Centre.

Further south, near the South African border, under the coastal dunes and off-shore, is one of the largest diamond deposits in the world, which have been mined for over a century. While some laudable efforts are being made to restore mine sites on this harsh, windy coast, it is a very difficult task, in one of the driest regions of the world.

During our travels, we met some of the restoration and conservation pioneers in the country, who are taking these vital actions to the next level, and working on more intimately linking wildlife conservation, the policies of both mining and tourism sectors and, in general, environmental education and capacity building. In the next blog post, we will talk more of the prospects and constraint for these initiatives.

The Huarango and Algarrobo forests of coastal Peru: rays of hope

James and Thibaud Aronson report from coastal Peru, where they travelled in December, with Oliver Whaley, of RBG Kew.

Yesterday, at our local market here in France, we saw Peruvian avocados. We’d seen them there before, and we don’t buy them. But we’d never really given them more than a passing thought. Now, having come back from coastal Peru, where they are grown, we have a very different outlook.

Passing through much of Peru’s southern coast is perhaps more interesting to geologists than ecologists. The tenuous ecological balance, and its rather checkered history since humans arrived, needs time to reveal its secrets. But the earth’s surface here is simply naked and laid out as for a desert geomorphology text book. An extension of the famous Atacama desert of northern Chile, it is one of the driest places on Earth, with an average annual rainfall of 0.3 mm, or barely more than one tenth of an inch.

Here more than in nearly any other desert, life is almost entirely confined to areas with some amount of moisture. As a result, the few river valleys that come down from the Andes form spectacular green ribbons among the dunes. They carry some water down from the rainstorms high in the mountains but the critical driver here is El Niño. It brings down tremendous amounts of water and sediment once every 6 to 15 years, thereby rejuvenating the whole system, and generating extremely fertile alluvial soils.

The last remaining stretch of Prosopis limensis riparian forest near Copara, Ica region, southern Peru.

500 years ago, the river valleys were occupied by dense woodlands or veritable forests of Prosopis limensis (local name – Huarango), which is often misidentified as Prosopis pallida, teeming with wildlife in the canopy and understories. Today, most of the Prosopis are gone, the excellent charcoal produced from their wood having been used up to fuel the stream engines of the now defunct coastal railway and, more recently, for fast food chicken restaurants ‘pollo a la brasa’ and millions of barbecue fires in cities and roadside restaurants. Instead, one now sees vast monocultures of asparagus, avocadoes, and table grapes, producing cash crops for the North American and European export markets.

This story of deforestation is in fact almost complete, with nearly 99% of the original vegetation having been removed.

There once were countless Prosopis trees such as this one, which has probably lived for a thousand years on this sand dune, near Copara.

Most of them fell to the charcoal burners’ axes, and even though it is now forbidden to harvest firewood from live trees, illegal cutting continues, as seen here, 20 meters from the tree pictured above.

Depressing? Yes, but as engaged ecologists, we were also encouraged that change is happening; there is cause for hope. There are program in community-based restoration led by Ecoan underway in the high Andes, near Cuzco and environs, and science and conservation efforts underway at the Missouri Botanical Garden’s station at Oxapampa.

We were lucky to spend 10 days with Oliver Whaley, from RBG Kew, who has been instrumental in many of the first initiatives attempting to reverse some of the damage done on this arid coast and to find a new path that explicitly includes restoration. Particularly noteworthy is a partnership he’s brokered with the large agroindustry supply chain, including a giant supermarket chain where almost half of the UK buys its vegetables, and which is the destination of a high percentage of the region’s produce.

The agro-industries overcome the lack of reliable rainwater by installing intensive irrigation systems, which although highly efficient, are driving unsustainable expansion even as they produce spectacular crop harvests.

However, the coast also experiences strong winds coming from the coast year-round, which require that rows of trees be planted as windbreaks to shield the valuable crops. Furthermore security hedging today is almost entirely composed of introduced water-guzzling African or Asian exotics. Under Whaley’s in-farm reforestation  program, some producers have begun planting native Prosopis, Parkinsonia, and Acacia trees yielding a mixed forest instead, which provides habitat for wildlife and also improves the neighboring soils through their capacity to fix atmospheric nitrogen in symbiosis with rhizobacteria. They require far less water than introduced trees, and will never become weeds. Agroindustry management has also donated land for restoration corridors, a vitally important undertaking at the landscape scale that has not yet been well-explored in coastal Peru or other drylands.

The Kew Peru team planted 7,000 trees and shrubs of 15 native species derived from the degraded tiny relicts. The results have been nothing short of astounding, with over 70 new native plant species, 45 bird species, various lizards, desert fox and wild guinea pigs recolonizing areas that were nothing but barren soil 9 years ago. (The full results of this work will be published in the spring). Whaley takes a practical and patient view – whereby to nurture back woodland and a cultural re engagement with what nature provides takes time and needs to show results.

A patch of restored land on the edge of an asparagus field, showing the difference 10 years make. Santiago de Ica, southern Peru.

Whaley and the local NGO, Conservamos por Naturaleza that he helped found and works closely with, is also committed to education and communication, working in Ica, Nasca, and elsewhere, to change people’s perception of the key desert plants such as Prosopis and Capparis, and their ecosystems, and of native biodiversity in general. Cultural reengagement, he argues, is about changing perception from symbols of a rural, backwards environment to be left behind in the wake of progress, to highly useful and valuable trees and woodlands that are part of the local heritage. These ecosystems clearly are worthy of pride, not only for their inherent value, but also because they offer the prospects of  sustainable, profitable agriculture that is also conservation-friendly.

The Huarango Festival in Ica, which focuses on the numerous products that can be extracted from the tree, such as algarrobina, a sweet spread, a sweet drink, high quality honey, ink, and more has been a large success, and is now in its eleventh year. Whaley also works with schools, working to restore small patches of native vegetation inside the school compounds and promoting ecological consciousness through small nurseries and gardening projects.

Seedlings in a native species nursery funded by the Royal Botanic Gardens, Kew, at the Faculty of Agronomy at the University of Ica.

Middle school students in their school’s nursery, in a town near Ica, where they grow native species and food crops and have a great time doing it.

The other unique feature of the southern coast is an inland archipelago of sorts, made up of coastal fog oases, or lomas, in Spanish. Fed by the moisture provided by coastal fogs, they rise from the surrounding desert and harbor herbaceous vegetation and in some cases various kinds of trees, all of which show high rates of endemism. Most of the lomas are sadly threatened by mining and other uses today, but Whaley has already succeeded in helping protect the new national reserve of Lomas San Fernando. This and other efforts , such as drone surveys and modelling, are conducted with help from Kew GIS staff, and Whaley’s team in Peru that includes Alfonso Orellana, Consuelo Borda, Ana Juarez and other dedicated workers. They are currently doing the baseline research in two other lomas reserves to help strengthen the case for protected area status.

The amazing vegetation supported almost entirely by coastal fogs in the Lomas de Atiquipa, home to an endemic very endangered Myrtaceae:  Myrcianthes ferreyrae.

 

A female Andean condor (Vultur gryphus), in the Lomas de San Fernando reserve, the only place in Peru where this raptor roosts near sea level.

Whaley and his co-workers are also engaged in restoration efforts the tropical northern coast of Peru, where the circumstances are rather different. The north coast receives significantly more rainfall than the south, i.e., about 100 mm per year (!), that is 4 inches. This permits the vegetation to climb out of the river valleys, and in fact, the local Algarrobo (Prosopis pallida and in the extreme North only P. juliflora along with hybrids between the two), and Capparis species, among others, still form true woodlands. Traditionally, the trees were preserved by the local people as their leaves and in particular their pods are remarkably nutritive, and provide prime forage for free-ranging cattle, the peoples’ primary source of income.

The remarkable woodlands dominated by Prosopis pallida (Algarrobo), in the Pomac Forest Sanctuary, Lambayeque Region, northern Peru.

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The Algarrobo trees have been preserved in large part because they provide excellent forage for the local people’s cattle.

However, a still poorly understood plague, apparently resulting from the combination of a small fly and a fungus, are decimating the woodlands; in some areas over 80% of the Algarrobo have apparently died. Just like in the South, El Niño is paramount in keeping the system healthy and, in particular, no Prosopis seedlings have been seen germinating in the last 50 years, except during El Niño years. What’s more, the next El Niño event is overdue: the last one came in 1997/1998, and now the system appears exhausted. Clearly the system is waiting for the next El Niño, and the long wait appears to have increased the Algarrobo’s vulnerability to the plague.

Severe Prosopis pallida dieback, near Talara, Piura region.

However, El Niño is coming this year, and according to the climate experts, it’s going to be a big one. As a result, Whaley and his team are scrambling to prepare as many Prosopis seeds as possible, to be sown during or right after the heavy rains. As the trees slowly dying from the plague usually fail to set seed, Whaley and his collaborators fear that much of the soil seed bank is exhausted and this could truly be the last chance for this species in its wild state.

A seed-ball with 4 native species, including Algarrobo, being prepared at a community nursery, near Salas, Lambayeque region.

Now there is an additional layer to the issue, which asks of would-be restorationists exactly what it is that they are trying to do. There hasn’t been nearly as much deforestation in Peru’s North coast as in the South, so there are still reasonably large tracts of native vegetation left intact. Further, apart from Algarrobo, none of the other five dominant native tree species, including two species of Capparis,  appear to be affected in any way by the plague.  Domestic cattle will also eat the leaves of these other trees and shrubs, though they aren’t quite as good as the Prosopis.

Therefore, some might say that this is just a natural transition occurring within an ecosystem, and it would be foolish, or even a case of trying to play God, to attempt to save the Prosopis at all costs. However, Whaley thinks differently, and we agree with him. The Algarrobo, like the Huarango, is a remarkable tree, fantastically well adapted to its environment, capable of living 1000 years of more, and clearly the keystone species of the riparian and related ecosystems where it occurs.

It forms remarkable canopies, and in areas where it is absent, we did not see the other tree species present produce anything like it, rather forming a much more open low savanna. Further, it has been a pillar of the various civilizations that have existed in the area for the last 4000 years. Therefore, Whaley is not yet ready to just let it go…

A thousand-year old Prosopis pallida in the Pomac Forest Sanctuary, possibly the oldest of its kind still alive in northern Peru…

 

Conservation and restoration in arid Australia – an uphill battle.

In their third report from arid Australia, James and Thibaud Aronson discuss some of the serious issues facing conservationists and restorationists.

Concerning the non-native animals in Australia, the general consensus today is that eradication is impossible: the only option that remains is control, in the form of fences or culling, or both. Yet, conflicts of opinion on the ethics of culling abound, even for the armies of feral cats that reportedly kill 75 million native animals every single night. Even fences have their pros and cons, in particular the interruption of the migration of thousands of emus.

Western Australia’s State Barrier Fence, 1170 km long, meant to control dingoes, dogs, foxes and other feral animals, with varying degrees of success.

Both feral cats and foxes are most lethal in areas with relatively little vegetation cover, that is, the massive dry interior of the continent. This is compounded by the monster fires that have plagued Australia since European settlement. A single such fire can burn down hundreds of thousands of hectares, leaving small mammals and other animals with nowhere to hide.

Even this rather small fire, which spared the trees (their dead appearance is deceptive; these trees will resprout), has almost entirely eliminated all low vegetation, leaving small animals vulnerable to cats and foxes. West MacDonnell National Park, Northern Territory.

What’s more, as mentioned in our previous blogpost, most land managers continue to burn on an annual basis without sufficient attention to the impact on animals and indeed many plants. Things are changing though.

In the seasonally dry, tropical Kimberley region, in the northwest, the Australian Wildlife Conservancy, or AWC, is testing new methods, focusing on patchy prescribed burning in the early dry season, and controlling cattle grazing. They are having good results with this approach in preserving more plant cover for small native animals and thereby reducing the lethal impact of feral cats. The AWC has also shown that their fire management techniques are not only beneficial for native animals, but also for pasture quality, and would therefore benefit pastoralists, whom Australians call graziers. Since most landowners in the area are graziers, let’s hope they will follow suit and try new fire management regimes. It is in this region, by the way, that occurs the endemic baobab of Australia, known here as Boab. To our surprise there are thousands of them, in a wide range of habitats. Some are estimated to be well over 1000 years old. Survival of this tree, at least, is clearly not threatened by fire or foxes, even if other problems – such as climate change – do exist. Let’s hope they go on thriving for another 1000 years.

A typical landscape of the Kimberley, dominated by the majestic boabs (Adansonia gregorii). King Leopold Ranges Conservation Park.

Another reason invoked for the proliferation of cats and foxes in Australia is the virtual absence of top predators to control them. This phenomenon, called meso-predator release, is also found in North America, where coyotes have greatly expanded following the extirpation of wolves throughout large portions of the continent. Therefore, some have suggested that allowing dingoes to maintain higher population numbers would have a significant effect on controlling cats and foxes. However, dingoes are still considered pests by pastoralists, and large amounts of money go into controlling them.

And that’s not the last of it. In the last 200 years, people have also introduced many exotic plant species, some of which have become terrible weeds, such as buffel grass (Cenchrus ciliaris) (see our previous blog post), but also Tamarix, Kutch (aka Bermuda grass, Cynodon dactylon), Karroo thorn (Acacia horrida) and others. By 2009, the Commonwealth Scientific and Industrial Research Organisation (CSIRO) estimated that introduced invasive plants were costing the country 4 billion Australian dollars a year in weed control and lost agricultural production, and causing “serious damage to the environment”. With climate change, it seems possible that numerous “lurking” or “sleeper” weeds such as the White weeping broom, Retama raetam, may increase their ranges and their negative impacts.

Buffel grass presents a particularly severe problem – and like the cats, and dingoes, it is controversial. It was one of dozens of African grasses intentionally introduced by Australian agricultural researchers to “improve” pasture for cattle. Indeed cattle do like it, but the problem is that the grass spreads with amazing tenacity and crowds out native grasses, and all other groundstory plants where it invades, and, it carries fire like few other plants. Control is possible, but it is tedious and expensive and is never 100% effective at a large-scale. Furthermore, the ranchers prefer it to the native grasses, and their ideas on when and how to burn are very different from those concerned with conservation. Indeed, only few of the people we met envision stopping prescribed fire altogether.

For example, Peter Latz,  a native of the Red Centre,  plant ecologist, and author we met in Alice Springs, has been conducting manual removal of buffel and Kutch on his own land. But his main focus has been on excluding fire altogether, and achieving thereby pretty impressive results.

 

Peter Latz in his garden, next to the hemi-parasitic quandong tree (Santalum acuminatum). Alice Springs.

For more on Peter Latz’s views and lifetime of experience in central Australia, see The Flaming Desert: Arid Australia – a Fire Shaped Landscape.

In our next blog post, we’ll talk about some of the other people and groups in arid and SW Australia undertaking serious steps towards restoration, while fully aware of the obstacles and the complexity of the challenge.