Peer-reviewed publications

Humanity is on a deeply unsustainable trajectory. We are exceeding planetary boundaries and unlikely to meet many international sustainable development goals and global environmental targets. Until recently, there was no broadly accepted framework of interventions that could ignite the transformations needed to achieve these desired targets and goals. As a component of the IPBES Global Assessment, we conducted an iterative expert deliberation process with an extensive review of scenarios and pathways to sustainability, including the broader literature on indirect drivers, social change and sustainability transformation. We asked, what are the most important elements of pathways to sustainability? Applying a social–ecological systems lens, we identified eight priority points for intervention (leverage points) and five overarching strategic actions and priority interventions (levers), which appear to be key to societal transformation. The eight leverage points are: (1) Visions of a good life, (2) Total consumption and waste, (3) Latent values of responsibility, (4) Inequalities, (5) Justice and inclusion in conservation, (6) Externalities from trade and other telecouplings, (7) Responsible technology, innovation and investment, and (8) Education and knowledge generation and sharing. The five intertwined levers can be applied across the eight leverage points and more broadly. These include: (A) Incentives and capacity building, (B) Coordination across sectors and jurisdictions, (C) Pre‐emptive action, (D) Adaptive decision‐making and (E) Environmental law and implementation. The levers and leverage points are all non‐substitutable, and each enables others, likely leading to synergistic benefits. Transformative change towards sustainable pathways requires more than a simple scaling‐up of sustainability initiatives—it entails addressing these levers and leverage points to change the fabric of legal, political, economic and other social systems. These levers and leverage points build upon those approved within the Global Assessment's Summary for Policymakers, with the aim of enabling leaders in government, business, civil society and academia to spark transformative changes towards a more just and sustainable world.

Connectivity conservation is aimed at sustaining animal movements and ecological processes important to ecosystem functioning and the maintenance of biodiversity. However, connectivity conservation plans are typically developed around a single species and rarely empirically evaluated for their relevance to others, thereby limiting our understanding of how connectivity requirements differ across species. We used an omnidirectional application of circuit theory and GPS data from six species to evaluate connectivity at multiple scales for multiple species within the world's largest transfrontier conservation landscape in southern Africa. We evaluated the effects of linear barriers, natural habitat types and anthropogenic land use on movement. We identified multispecies connectivity hotspots as areas where current flow was concentrated or channelled through pinch points. To evaluate surrogate species for connectivity, we evaluated the correspondence among single‐species connectivity across the entire landscape and also examined whether a more localized corridor for African savanna elephant Loxodonta africana captured high multispecies connectivity values. Connectivity models revealed many intact areas across the landscape with diffuse current flow, but also evidence that fences, rivers, roads and areas of anthropogenic use acted as strong barriers to movement—particularly in the case of fences, which completely blocked female elephant movement. Tests of correspondence among single‐species connectivity models revealed spotted hyaena and African wild dog as the strongest surrogate species of connectivity. Female elephants were found to be the weakest surrogate species of connectivity at the landscape scale. However, focusing within a localized elephant corridor revealed the areas of concentrated or channelled connectivity for most species in our study. Synthesis and applications. Our results suggest that the single‐species focus permeating connectivity literature may result in conservation plans that poorly conserve the connectivity needs of co‐occurring species. Our study also highlights the importance of testing the efficacy of surrogate species for connectivity at multiple scales. We recommend evaluating multispecies connectivity to prioritize areas for conservation that safeguard the connectivity needs of multiple species of conservation concern.

Climate change is expected to dramatically alter the distribution of many marine megafauna, impacting the people and economies that depend upon them. We build on the recent literature by developing a framework to describe the effects these changes will have on marine megafauna. With the goal to assist policymakers and grass roots organizers, we identify three illustrative pathways by which climate change drives these range shifts: (1) effects on habitat and shelter, (2) impacts on reproduction and disease, and (3) changing distribution of sources of food. We examine non-climate factors that may constrain or enable megafauna to adapt, creating winners and losers both for the species and the people dependent upon them. Finally, we comment on what management strategies exist at international and local scales that could help mitigate these impacts of climate change so that we, as a global community, can ensure that marine megafauna and people can best co-exist in a changing world.

The environmental costs of human activities (Steffen et al., 2007) and the social and psychological costs of overconsumption and materialism (Dittmar et al., 2014) underscore the importance of identifying whether and how individuals can reduce their consumption while improving their well-being. Interest in this ‘double dividend’ (Alfredsson et al., 2018; Jackson, 2008) was sparked by evidence of a threshold beyond which additional GDP or household income has little impact on well-being, happiness or life satisfaction (Easterlin et al., 2010; Kahneman and Deaton, 2010; though see Pouwels et al., 2008 for evidence that the positive effect of income on well-being may be underestimated). This literature was coupled with evidence that materialist values and the desire for higher income are associated with lower well-being and life satisfaction (Diener and Seligman, 2004; Kasser, 2017) to suggest that sustainable consumption may not require sacrifice and may, in fact, be rewarding. Recent studies have explored the double dividend at the macro-level by measuring the environmental efficiency of well-being (EWEB) (Dietz et al., 2009; Knight and Rosa, 2011), or carbon intensity of well-being (Jorgenson and Givens, 2015) to identify nations with high levels of well-being despite relatively small environmental impacts. Other studies have measured EWEB at the household (Ambrey and Daniels, 2017) or individual level (Claborn and Brooks, 2019), explored correlations between subjective well-being and carbon emissions (Andersson et al., 2014; Verhofstadt et al., 2016), and examined whether involvement in voluntary simplicity movements is associated with higher life satisfaction (Alexander and Ussher, 2012; Rich et al., 2017). These and other individual- or household-level studies have found mixed evidence for the double-dividend (see also Verhofstadt et al., 2016; Vita et al., 2019; Schmitt et al., 2018), which suggests that double-dividend relationships are complex, and limitations in existing research may have made it difficult to detect specific tradeoffs and synergies between sustainable consumption and well-being. More specifically, existing studies have tended to use aggregate measures of consumption (e.g., transportation and shelter) and/or unidimensional measures of well-being (e.g., one-item measurement) and have generally not accounted for how local socio-cultural context, such as norms and culture, may shape the relationship between sustainable consumption and well-being. With this study, we address the above shortcomings and examine whether and which sustainable consumption behaviors are associated with higher well-being, and whether these relationships depend on one's socio-cultural context. We sample two neighborhoods to assess differences in local contextual factors. We also examine whether residents' income, rather than neighborhood context, influences the relationship between sustainable consumption and well-being. We define sustainable consumption as behaviors that contribute to a smaller ecological footprint relative to more environmentally impactful alternatives. Included in this conceptualization are “curtailment” behaviors (e.g. purchasing fewer material goods like clothing or electronics; Karlin et al., 2014), “efficiency” behaviors (e.g. driving a more fuel-efficient vehicle), and behaviors intended to reduce waste (e.g. recycling paper and plastic).

COVID-19 is exposing the fragility of the goals adopted by the United Nations — two-thirds are now unlikely to be met.

Healthy rivers provide a broad range of services that benefit economies and communities but the concepts of water security, as well as water management in practice, have tended to focus on a narrow set of those services. Accomplishing the diverse objectives bundled under water security—including water quantity and quality, linkages with food security, risk management and ecosystem conservation—will require a more holistic valuing of rivers’ services coupled with policies and mechanisms to maintain and restore those values. Rivers have typically been viewed as sources of water to support irrigation, water supply or hydropower. While the water that rivers provide often has immense value to economies—and thus it is this role where rivers are well represented within frameworks for water security—rivers provide a diverse range of other services that encompass, but extend beyond, water as a resource that can be defined by volume or quality. These services can also produce vital benefits for economies and communities and they are generated by rivers as complex biophysical systems, not just as conduits for delivering water. Examples of these services include fisheries, floodplains that reduce flood risk, sediment delivery to deltas, and components of the channel network that regulate water quantity and quality. Concepts such as natural capital and ecosystem services are intended to better value these services, however the valuations produced are often not effectively integrated into decisions or management. Although rigorous science provides an important foundation for embedding the value of rivers within water security, translating those values into management and policy will require the communication of river values into terms and numbers that matter to key audiences and the assembly of coalitions to translate value into action.

In many savannah regions of Africa, pronounced seasonal variability in rainfall results in wildlife being restricted to floodplains and other habitats adjacent to permanent surface water in the dry season. During the wet season, rainfall fills small‐scale, ephemeral water sources that allow wildlife to exploit forage and other resources far from permanent surface water. These water sources remain difficult to quantify, however, due to their small and ephemeral nature, and as a result are rarely included in quantitative studies of wildlife distribution, abundance, and movement. Our goal was to map ephemeral water in Bwabwata National Park in Namibia using two different approaches and to relate measures of ephemeral water to the abundance, distribution, and movement of two large wildlife species. We used high‐resolution Google Earth and Esri World imagery to visually identify waterholes. Additionally, we used Sentinel‐2 satellite imagery to map ephemeral water across the study area using the Normalized Difference Water Index. With these mapped waterhole layers and data from GPS‐collared individuals of African elephant (Loxodonta africana) and African buffalo (Syncerus caffer), we evaluated the importance of ephemeral water in conditioning abundance and movement of these two species. The two approaches to mapping ephemeral water resulted in the visual identification of nearly 10,000 waterholes, and a predicted ephemeral water layer of ~76% accuracy. The inclusion of ephemeral water into models of abundance and movement resulted in improved goodness of fit relative to those without water, and water impacts on abundance and movement were among the strongest of all variables considered. The potential importance of ephemeral water in conditioning the movements and distributions of large herbivores in African savannahs has been difficult to quantify relative to vegetation drivers. Our results suggest research into ephemeral water impacts deserves more attention.

Important operational changes that have gradually been assimilated and new approaches that are developing as part of the movement toward sustainable intensive aquaculture production systems are presented via historical, current, and future perspectives. Improved environmental and economic sustainability based on increased efficiency of production continues to be realized. As a result, aquaculture continues to reduce its carbon footprint through reduced greenhouse gas emissions. Reduced use of freshwater and land resources per unit of production, improved feed management practices as well as increased knowledge of nutrient requirements, effective feed ingredients and additives, domestication of species, and new farming practices are now being applied or evaluated. Successful expansion into culture of marine species, both off and on shore, offers the potential of substantial increases in sustainable intensive aquaculture production combined with integrative efforts to increase efficiency will principally contribute to satisfying the increasing global demand for protein and food security needs.

Much recent attention has focused on the potential of trees and forests to mitigate ongoing climate change by acting as sinks for carbon. Anderegg et al. review the growing evidence that forests' climate mitigation potential is increasingly at risk from a range of adversities that limit forest growth and health. These include physical factors such as drought and fire and biotic factors, including the depredations of insect herbivores and fungal pathogens. Full assessment and quantification of these risks, which themselves are influenced by climate, is key to achieving science-based policy outcomes for effective land and forest management.

The term “Anthropocene” has been suggested as the current epoch (denoting the current geological age) and is viewed as the period where human-based activity is the dominant influence on climate and the environment (Lewis and Maslin, 2015). Arguably, one of the most prevalent and visible effects of this anthropogenic activity has manifested in the equatorial tropics—where coral reef ecosystems have suffered alarming declines (Pandolfi et al., 2003; Hughes et al., 2017). For example, recent increases in mass bleaching events brought about by prolonged periods of elevated sea surface temperatures highlight a worrying trend, with predictions that over half of reefs will experience annual severe bleaching before 2050 (van Hooidonk et al., 2016). For this reason, coral reefs have often been referred to as “canaries in the coal mine” for the marine biome. Yet reefs continue to be crucial sources of food, protection, livelihoods, and cultural identity for many people around the world (Teh et al., 2013; Hicks and Cinner, 2014; Lau et al., 2019). It is therefore critical that the link between healthy reefs, food security, and sustainable community livelihoods is maintained into the future.