John S. Donaldson

• PhD
• Honorary Professor at University of Pretoria

The islands of the Ryukyu archipelago in Japan are biologically diverse, supporting numerous plant and animal taxa found nowhere else. One of the most iconic plants is Cycas revoluta Thunb., the only cycad native to Japan. At this moment, the community of cycad researchers is concerned about the impacts caused by the recent invasion of the cycad au...

The Red List Index (RLI) is an indicator of the average extinction risk of groups of species and reflects trends in this through time. It is calculated from the number of species in each category on the IUCN Red List of Threatened Species, with trends influenced by the number moving between categories when reassessed owing to genuine improvement or...

This paper summarises the findings of the IPBES assessment for the sustainable use of wild species, which is extensive in both high- and low-income countries. At least 50,000 wild species are usedby billions of people around the world for food, energy, medicine, material, education or recreation, contributing significantly to efforts to achieve the...

A recent report from the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) assessed how the sustainable use of wild species benefits people and nature, and which policies work best to prevent unsustainable exploitation. In the context of an accelerating and alarming biodiversity crisis, the assessment findings...

Monitoring of the ecological and social, including economic aspects of uses of wild species is critical for sustainable use. Progress towards achieving the Sustainable Development Goals and the Aichi Biodiversity Targets is assessed using global indicators, however to date, there is not a comprehensive set of global indicators able to monitor statu...

Honey bees are the most economically important crop pollinator worldwide. They depend on a diversity of pollen for reproduction and colony growth. However, the influence of landscape composition on diversity and quantity of pollen collection by honey bees remains largely unexplored, particularly in variegated landscapes. Pollen on honey bees was tr...

A controversy at the 2016 IUCN World Conservation Congress on the topic of closing domestic ivory markets (the 007, or so-called James Bond, motion) has given rise to a debate on IUCN's value proposition. A cross-section of authors who are engaged in IUCN but not employed by the organization, and with diverse perspectives and opinions, here argue f...

This study investigates the population structure and life history traits of the Critically Endangered cycad, Encephalartos latifrons. Populations of E. latifrons have been considered functionally extinct because no natural recruitment has been observed in the wild for almost 30 years. The discovery of a previously undocumented population of E. lati...

This study evaluates how a modelling approach to determine areas of suitable habitat for the Critically Endangered Albany cycad Encephalartos latifrons can assist in systematic conservation planning for this and other rare and threatened cycads. A map distinguishing suitable from unsuitable habitat for E. latifrons was produced and important enviro...

This study investigates the population structure and life history traits of the Critically Endangered cycad, Encephalartos latifrons. Populations of E. latifrons have been considered functionally extinct because no natural recruitment has been observed in the wild for almost 30 years. The discovery of a previously undocumented population of E. lati...

Despite its recognition as an important global resource for conservation, the International Union for Conservation of Nature's (IUCN) Red List of Threatened Species only provides assessments of extinction risk for a small and biased subset of known biodiversity. A more complete Red List can better support species-level conservation by indicating ho...

Most pollination ecosystem services studies have focussed on wild pollinators and their dependence on natural floral resources adjacent to crop fields. However, managed pollinators depend on a mixture of floral resources that are spatially separated from the crop field. Here, we consider the supporting role these resources play as an ecosystem serv...

BLU Classification for each floral resource-type Detailed methods of the BLU classification for each floral resource-type: Natural vegetation, eucalypts and canola (see ‘Bee Landscape Unit (BLU) definition and floral resource classification’ in manuscript).

Hive adjusted dataset Summary of data derived from the area of available resource-types adjusted according to the number of hives associated with the apiary site (see ‘Data analysis’ in manuscript).

The distribution of the Cape managed honeybee system in South Africa Map of Cape managed honeybee system including the Western Cape deciduous fruit growing areas (Extracted from Western Cape Department of Agricultural Department Aerial Commodity Census, 2013) and the distribution of apiary sites based on beekeeper subsample of 120 sites (using quar...

Beekeeper dataset Summary of data derived from interviews with beekeepers (see ‘Data analysis’ in manuscript).

Landscape dataset Summary of data derived from the available resource-types (see ‘Data analysis’ in manuscript).

Cycads are the most endangered of plant groups based on IUCN Red List assessments; all are in Appendix I or II of CITES, about 40% are within biodiversity ‘hotspots,’ and the call for action to improve their protection is long-standing. We contend that progress in this direction will not be made until there is better understanding of cycad pollen,...

This study evaluates how a modelling approach to determine areas of suitable habitat for the Critically Endangered Albany cycad Encephalartos latifrons can assist in systematic conservation planning for this and other rare and threatened cycads. A map distinguishing suitable from unsuitable habitat for E. latifrons was produced and important enviro...

Cycads were a dominant plant functional type during the Mesozoic Era when atmospheric carbon dioxide [CO2] greatly exceeded current conditions. Cycads, now rare and endangered, are slow-growing perennial gymnosperms that develop carbon-rich structural biomass, such as sclerophyllous leaves, dense stems and massive reproductive cones. Is cycad carbo...

Sustainable harvesting practices are important for conserving plant species and their habitats, but also the livelihoods of those that depend on them. Aloe ferox, a valuable natural resource harvested for its leaves, is the focus of a recent rural development initiative in the Eastern Cape of South Africa. This has the potential to benefit poor res...

This is a condensed version of an article that was published online in Biodiversity and Conservation in October 2016. It has been adapted from the abstract of the article, with a few added details, illustrated by an image from the published article and a photo supplied by Karin Van der Walt. Comparative images from the original article: A–C: Enceph...

Although South African cycads are known to be declining in the wild, there is at present no broad-scale, quantitative analysis to support this view. In this study the fate of 626 individual cycads was assessed from 107 repeat photographs taken at 53 locations over three time-steps (broadly 1940s, mid-1990s and 2014). Of the cycads photographed in t...

Cycad Reproduction (in three languages)

Cycads and their distribution (in Uganda), in three languages

Brood-site mutualisms represent extreme levels of reciprocal specialization between plants and insect pollinators, raising questions about whether these mutualisms are mediated by volatile signals and whether these signals and insect responses to them covary geographically in a manner expected from coevolution. Cycads are an ancient plant lineage i...

Plants provide fundamental support systems for life on Earth and are the basis for all terrestrial ecosystems; a decline in plant diversity will be detrimental to all other groups of organisms including humans. Decline in plant diversity has been hard to quantify, due to the huge numbers of known and yet to be discovered species and the lack of an...

Insect pollinators, both managed and wild, have become a focus of global scientific, political and media attention because of their apparent decline and the perceived impact of this decline on crop production. Crop pollination by insects is an essential ecosystem service that increases the yield and quality of approximately 35% of crops worldwide....

South Africa has the world's richest temperate flora, with 20,456 indigenous vascular plant taxa recorded. With the current estimate of the global flora at 379,881 taxa, 5% of the world's plant diversity is represented within South African borders. Between 2004 and 2008, South African botanists completed a comprehensive assessment of the status of...

Background and Aims Ontogenetic patterns of odour emissions and heating associated with plant reproductive structures may have profound effects on insect behaviour, and consequently on pollination. In some cycads, notably Macrozamia, temporal changes in emission of specific odour compounds and temperature have been interpreted as a ‘push–pull’ inte...

We aggregated data on butterfly-host plant associations from existing sources in order to address the following questions: (1) is there a general correlation between host diversity and butterfly species richness?, (2) has the evolution of host plant use followed consistent patterns across butterfly lineages?, (3) what is the common ancestral host p...

Text file with example of R-code. The file contains commented R-code to use with the Dataset S1. (PDF)

Compressed R-data file with objects used in the analysis. The file contains the association matrices (Aij, Cij Zij and Xij), the butterflies phylogenies (Alternative1.tree, Alternative2.tree and Traditional.tree), plant phylogeny (APGorders.tree), and summary table (Summary.table). (CSV)

File in comma separated value format used to build Figure 2. The file contains the number of butterfly species and number of butterfly species with host plant records among regions and subfamilies. (CSV)

South Africa has the world's richest temperate flora, with 20,456 indigenous vascular plant taxa recorded. With the current estimate of the global flora at 379,881 taxa, 5% of the world's plant diversity is represented within South African borders. Between 2004 and 2008, South African botanists completed a comprehensive assessment of the status of...

Variation in traits across species distribution ranges is often indicative of diversifying evolution that can lead to speciation. Of particular interest is whether traits vary clinally or abruptly because the latter pattern can be indicative of incipient speciation. Understanding of intraspecific variation in chemical traits is still in its infancy...

Ecological risk analysis (ERA) is a structured evaluation of threats to species, natural communities, and ecosystem processes from pollutants and toxicants and more complicated living stressors such as invasive species, genetically modified organisms, and biological control agents. Such analyses are typically conducted by a narrowly-focused group o...

Aim Bees are the most important pollinators of flowering plants and essential ecological keystone species contributing to the integrity of most terrestrial ecosystems. Here, we examine the potential impact of climate change on bees’ geographic range in a global biodiversity hotspot. Location South Africa with a focus on the Cape Floristic Region (C...

Declining populations of less than 250 mature individuals are symptomatic of many Critically Endangered cycads, which, globally, comprise the most threatened group of organisms as a result of collecting and habitat loss. Survival plans focus on law enforcement, reintroduction, and augmentation programmes using plants from the wild and botanical gar...

Mean annual soil respiration correlates with net primary productivity and therefore provides an indication of ecosystem functioning. Soil respiration, however, varies considerably in space and time owing to the influence of factors such as soil nutrient content, temperature and water content. Comparing soil respiration across a fence-line separatin...

Ecology Letters (2011) 14: 251–259 Ongoing expansion of large-scale agriculture critically threatens natural habitats and the pollination services they offer. Creating patches with high plant diversity within farmland is commonly suggested as a measure to benefit pollinators. However, farmers rarely adopt such practice, instead removing naturally o...

The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) came into effect in 1975 to protect certain species of wild fauna and flora against over-exploitation through international trade. Determining which trade is detrimental to the survival of species in the wild can be a major difficulty in the implementation o...

The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) came into effect in 1975 to protect certain species of wild fauna and flora against over-exploitation through international trade. Determining which trade is detrimental to the survival of species in the wild can be a major difficulty in the implementation o...

Most, if not all, extant cycads are pollinated by insects which use the cones as larval brood sites. These interactions appear to be mediated by cone volatiles, and, in some species, by patterns of thermogenesis. We investigated the chemical composition of volatile emissions and patterns of thermogenesis in cones of the South African cycad Encephal...

Assessing Biodiversity Declines Understanding human impact on biodiversity depends on sound quantitative projection. Pereira et al. (p. 1496 , published online 26 October) review quantitative scenarios that have been developed for four main areas of concern: species extinctions, species abundances and community structure, habitat loss and degradati...

Earthworm densities, mesofaunal and microbiological feeding activity, and soil moisture were measured as indicators of soil health. Fence line contrast sites were used to compare soil organism communities, infiltration rates and soil temperatures of natural vegetation remnants with adjacent transformed lands. Natural remnants retain soil moisture a...

A new sub population of Cycas beddomei Dyer (Cycadaceae), hitherto known as endemic to Seshachalam hills (Tirupati-Kadapa hills) of Andhra Pradesh, India and categorised as ‘endangered’ in IUCN Red List, is reported from Velikonda hills (Nellore-Kadapa districts) of Andhra Pradesh. Hence its global distribution status is hereby revised. Combined da...

Studies of the pollination ecology of the South African cycad, Encephalartos friderici-guilielmi Lehm, were carried out to determine the role played by insects and to identify the key pollinators. Surveys of insects on the male and female cones at the time of pollination indicated that three beetle species were present in sufficient numbers during...

The contributions of botanic gardens to conservation biology and global-change research need to be understood within the context of the traditional strengths of such gardens in herbarium collections, living collections and interactions with the public. Here, I propose that research in conservation planning, modelling species responses to climate ch...

Renosterveld is a grassy shrubland with a diverse understory of geophytes. Exceptional plant diversity and endemism, combined with considerable fragmentation due to transformation to cropland, make this vegetation type a conservation priority. The provision of formal reserves is difficult in highly fragmented landscapes. One possible way of motivat...

Data from 199 plots in the semi-arid Karoo showed that relationships between soil infiltrability and plant cover/species richness, as depicted by boundary lines, yielded ecological insights not evident if only commonly measured soil properties such as pH, electrical conductivity and the content of clay, silt, sand, nitrogen and carbon were consider...

Weevils in the tribe Amorphocerini have been implicated in pollination of Encephalartos species in southern Africa. The services they render these plants and the unique attributes of the cycad-weevil interaction make them important from both conservation and evolutionary standpoints. Oberprieler [Oberprieler, R.G., 1996. Systematics and evolution o...

A preliminary investigation of the diversity and density of small mammals in four structurally distinct habitat types in an actively-utilized farming landscape was carried out. We sought to understand how diversity and density are influenced by landscape structure, habitat structure and management decisions. Farmers in the area believe small mammal...

A preliminary investigation of the diversity and density of small mammals in four structurally distinct habitat types in an actively-utilized farming landscape was carried out. We sought to understand how diversity and density are influenced by landscape structure, habitat structure and management decisions. Farmers in the area believe small mammal...

Female eggs of Coccophagus atratus are deposited within the haemolymph of coccoid scale insects. Male eggs are deposited on to late larval and prepupal stages of parasitoids of scale insects, including conspecifics. When presented with either one host type or a combination of both host types, female C.atratus deposit all their available eggs, assig...

1. Spulungiu endius Walker is a solitary parasitoid of house fly puparia. 2. The sex and size of S.endius was not related to host size. 3. In the laboratory the mean sex ratio of all offspring of nine groups, each comprising twenty females, was consistently female-biased (x = 83.5%, range 79–87%). The sex ratio in the field was less female-biased a...

Effects of egg availability on daily ovipositional activity were determined for Coccophagus atratus Compere (Hymenoptera: Aphelinidae). Females were observed for 6 h per day for their entire adult lives. Observed ovipositional activity was analysed in relation to egg maturation before and after emergence, egg depletion during oviposition and egg re...

Antliarhinus zamiae (Thunberg) and A. signatus Gyllenhal are the only insects known in which the larvae feed exclusively on the cycad gametophyte. In their host plants, species of the cycad genus Encephalartos (Zamiaceae), the gametophyte is protected by a three-layered integument and substantial sporophyll tissues. Adaptation for oviposition into...

A deviation from the classical beetle pollination syndrome of dull-coloured flowers with an unpleasant scent is found in the Greater Cape Floral Region of South Africa. Here, monkey beetles (Scarabaeidae) visit brightly coloured, odourless flowers with conspicuous dark spots and centres (beetle marks). The role of flower colour and markings in attr...

In the biodiversity rich regions of western South Africa transhumance grazing strategies were practised for thousands of years. Today only vestiges of these systems remain with private ownership restricting seasonal mobility. Cultivation practices have created a mosaic landscape transforming the resource base, and we have a limited understanding of...

Abstract Intensive pastoralism with goats transforms semiarid thicket in the Eastern Cape, South Africa from a dense vegetation of tall shrubs to an open landscape dominated by ephemeral grasses and forbs. Approx. 800 000 ha of thicket (which prior to the introduction of goats had a closed canopy and a Portulacaria afra Jacq. component) have been t...

Using spatial predictions of future threats to biodiversity, we assessed for the first time the relative potential impacts of future land use and climate change on the threat status of plant species. We thus estimated how many taxa could be affected by future threats that are usually not included in current IUCN Red List assessments. Here, we compu...

Complementary field and laboratory tests confirmed and quantified the pollination abilities of Tranes sp. weevils and Cycadothrips chadwicki thrips, specialist insects of their respective cycad hosts, Macrozamia machinii and M. lucida. No agamospermous seeds were produced when both wind and insects were excluded from female cones; and the exclusion...

Cape porcupines (Hystrix africaeaustralis) appear to have an important influence on landscapes through both biotic (foraging) and abiotic (soil turnover) impacts. Porcupine abundance and abiotic effects across the landscape were investigated in Nieuwoudtville, South Africa, a semi-arid area characterized by an extraordinary diversity and abundance...

Carbon (C) storage in biomass and soils is a function of climate, vegetation type, soil type and land management. Carbon storage was examined in intact indigenous vegetation and under different land uses in thicket (250–400 mm mean annual precipitation), xeric shrubland (350 mm), karoo (250 mm), and grassland (900–1200 mm). Carbon storage was as fo...

Cone traits (volatile components and thermogenesis) of three cycad species in the genus Macrozamia were examined for differences related to their specific insect pollinators, the weevil, Tranes spp., or the thrips, Cycadothrips chadwicki. Linalool (>80% of emissions) dominated cone volatile components of M. machinii (Tranes-pollinated) and beta-myr...

This book presents the current state of our knowledge of the systematics of the approximately 300 species of cycads. It has been developed from 15 papers presented at the conference in Miami. Guidelines are presented for the designation of species, species boundaries and species groupings, thus clarifying what has been a confused area of research....

Collection of plants and seeds from wild populations threatens a large number of cycad species. We investigated to what extent individual life history stages contribute to population growth (l) and compared two species with major differences in life histories in the African genus Encephalartos: Encephalartos cycadifolius, a highly persistent grassl...

Fossil fuel combustion and changes in land use have resulted in a 38% increase in atmospheric CO2 since pre-industrial times. This increase in a greenhouse gas is an experiment in global climate which may have catastrophic results. The sequestration of carbon from the atmosphere into soils or vegetation is one way to buy time for the implementation...

Much of the worlds biological diversity exists outside of a formal protected reserve network, often on land that is managed for some form of agricultural production and the maintenance of rural livelihoods. Effective biodiversity conservation will therefore require innovative ways to merge the needs of farmers and rural communities with the need to...

We examined the effects of habitat fragmentation on the pollinator diversity and reproductive success of seven perennial plant species in renosterveld shrublands in South Africa. We sampled pollinators in small (0.5–2 ha), medium (3–10 ha), and large (>30 ha) habitat fragments during the peak flowering period in spring and summer. We also compared...

A form of lowland, sandplain Fynbos restricted to the Cape Flats near the city of Cape Town is the South African vegetation type most threatened by urban and agricultural development. Cape Flats Fynbos remnants, totaling 4.8 km², contain 14 plant species endemic to the Cape Flats scattered through four protected areas and 11 unprotected vegetation...