Challenging the scientific foundations for an IUCN Red List of Ecosystems

The International Union for Conservation of Nature (IUCN) is currently discussing the development of a Red List of Ecosystems (RLE) that would mirror the categories and criteria used to assess the conservation status of species. The suggested scientific foundations for the RLE are being considered by IUCN for adoption as the backbone of the RLE. We identify conceptual and operational weaknesses in the draft RLE approach, the categories, and criteria. While species are relatively well-described units, there is no consistent means to classify ecosystems for assessing conservation status. The proposed RLE is framed mostly around certain features of ecosystems such as broad vegetation or habitat types, and do not consider major global change drivers such as climate change. We discuss technical difficulties with the proposed concept of ecosystem collapse and suggest it is not analogous to species extinction. We highlight the lack of scientific basis for the criteria and thresholds proposed by the RLE, and question the need to adopt the structure of the Red List of Species for an RLE. We suggest that the proposed RLE is open to ambiguous interpretations and uncertain outcomes, and that its practicality and benefit for conservation should be carefully evaluated before final approval

The Madingley general ecosystem model predicts bushmeat yields, species extinction rates and ecosystem-level impacts of bushmeat harvesting

Traditional approaches to guiding decisions about harvesting bushmeat often employ single-species population dynamic models, which require species- and location-specific data, are missing ecological processes such as multi-trophic interactions, cannot represent multi-species harvesting and cannot predict the broader ecosystem impacts of harvesting. In order to explore an alternative approach to devising sustainable harvesting strategies, we employ the Madingley general ecosystem model, which can simulate ecosystem dynamics in response to multi-species harvesting given nothing other than location-specific climate data. We used the model to examine yield, extinctions and broader ecosystem impacts, for a range of harvesting intensities of duiker-sized endothermic herbivores. Duiker antelope (such as Cephalophus callipygus and Cephalophus dorsalis) are the most heavily hunted species in sub-Saharan Africa, contributing 34–95% of all bushmeat in the Congo Basin. Across a range of harvesting rates, the Madingley model gave estimates for optimal harvesting rate, and extinction rate, that were qualitatively and quantitatively similar to the estimates from conventional single-species Beverton–Holt model. Predicted yields were somewhat greater (around five times, on average) for the Madingley model than the Beverton–Holt, which is partly attributable to the fact that the Madingley simulates multi-species harvesting from an initially pristine ecosystem. Also, the Madingley model predicted a background local extinction probability for the target species of at least 10%. At medium and high levels of harvesting of duiker-sized herbivores, the Madingley model predicted statistically significant, but moderate, reductions in the densities of the targeted functional group; increases in small-bodied herbivores; decreases in large-bodied carnivores; and minimal ecosystem-level impacts overall. The results illustrate how general ecosystem models such as the Madingley model could potentially be used more widely to help estimate sustainable harvesting rates, bushmeat yields and broader ecosystem impacts across different locations and target species

Uncertainty in identifying local extinctions: the distribution of missing data and its effects on biodiversity measures

Identifying local extinctions is integral to estimating species richness and geographic range changes and informing extinction risk assessments. However, the species occurrence records underpinning these estimates are frequently compromised by a lack of recorded species absences making it impossible to distinguish between local extinction and lack of survey effort-for a rigorously compiled database of European and Asian Galliformes, approximately 40% of half-degree cells contain records from before but not after 1980. We investigate the distribution of these cells, finding differences between the Palaearctic (forests, low mean human influence index (HII), outside protected areas (PAs)) and Indo-Malaya (grassland, high mean HII, outside PAs). Such cells also occur more in less peaceful countries. We show that different interpretations of these cells can lead to large over/under-estimations of species richness and extent of occurrences, potentially misleading prioritization and extinction risk assessment schemes. To avoid mistakes, local extinctions inferred from sightings records need to account for the history of survey effort in a locality

Creating win-wins from trade-offs? Ecosystem services for human well-being: A meta-analysis of ecosystem service trade-offs and synergies in the real world

Ecosystem services can provide a wide range of benefits for human well-being, including provisioning, regulating and cultural services and benefitting both private and public interests in different sectors of society. Biophysical, economic and social factors all make it unlikely that multiple needs will be met simultaneously without deliberate efforts, yet while there is still much interest in developing win-win outcomes there is little understanding of what is required for them to be achieved. We analysed outcomes in a wide range of case studies where ecosystem services had been used for human well-being. Using systematic mapping of the literature from 2000 to 2013, we identified 1324 potentially relevant reports, 92 of which were selected for the review, creating a database of 231 actual or potential recorded trade-offs and synergies. The analysis of these case studies highlighted significant gaps in the literature, including: a limited geographic distribution of case studies, a focus on provisioning as opposed to non-provisioning services and a lack of studies exploring the link between ecosystem service trade-offs or synergies and the ultimate impact on human well-being. Trade-offs are recorded almost three times as often as synergies and the analysis indicates that there are three significant indicators that a trade-off will occur: at least one of the stakeholders having a private interest in the natural resources available, the involvement of provisioning ecosystem services and at least one of the stakeholders acting at the local scale. There is not, however, a generalisable context for a win-win, indicating that these trade-off indicators, although highlighting where a trade-off may occur do not indicate that it is inevitable. Taking account of why trade-offs occur (e.g. from failures in management or a lack of accounting for all stakeholders) is more likely to create win-win situations than planning for a win-win from the outset. Consequently, taking a trade-offs as opposed to a win-win approach, by having an awareness of and accounting for factors that predict a trade-off (private interest, provisioning versus other ES, local stakeholder) and the reasons why trade-offs are often the outcome, it may be possible to create the synergies we seek to achieve.This is the published version. It is available from Elsevier in Global Environmental Change here: http://www.sciencedirect.com/science/article/pii/S0959378014001320

The natural capital framework for sustainably efficient and equitable decision making

This is the author accepted manuscript. The final version is available from Nature Research via the DOI in this record.The concept of ‘natural capital’ is gaining traction internationally as recognition grows of the central role of the natural environment in sustaining economic and social wellbeing. It is therefore encouraging to see the first signs of a ‘natural capital approach’ to decision making being accepted within government policy processes and the private sector. However, there are multiple different understandings of this ‘approach’, many of which misuse or omit key features of its foundations in natural science and economics. To address this, we present a framework for natural capital analysis and decision making that links ecological and economic perspectives.Natural Environment Research Council (NERC)Turing-HSBC-ONS Economic Data Science Awards 2018Wellcome Trus

Targeting conservation actions at species threat response thresholds

To improve the status of the world’s biodiversity by 2030, conservation actions must not only seek to halt or slow biodiversity loss, they must increase species’ populations. A better mechanistic understanding of biodiversity loss and of species’ sensitivities to certain intensities of threats is needed to target conservation actions effectively. Moving beyond ordinal space-for-time substitution analyses, towards monitoring concurrent changes in threats and species’ populations over time will help achieve this. We propose a framework to quantify species’ response thresholds along gradients of threat intensity, using a combination of threat-sensitive taxa, biogeographic regions, and biomes. This framework will allow efficient targeting of conservation actions, of relevance to global policy-making

Defining and delivering resilient ecological networks: nature conservation in England

1.Planning for nature conservation has increasingly emphasised the concepts of resilience and spatial networks. Although the importance of habitat networks for individual species is clear, their significance for long‐term ecological resilience and multi‐species conservation strategies is less established. 2.Referencing spatial network theory, we describe the conceptual basis for defining and assessing a network of wildlife areas that supports species’ resilience to multiple forms of perturbations and pressures. We explore actions that could enhance network resilience at a range of scales, based on ecological principles, with reference to four well‐established strategies for intervention in a spatial network (“Better, Bigger, More and Joined”) from the influential Making Space for Nature report by Lawton et al. (2010). 3.Building existing theory into useable and scalable approaches applicable to large numbers of species is challenging but tractable. We illustrate the policy context, describe the elements of a long‐term adaptive management plan and provide example actions, metrics and targets for early implementation using England as a case study, where there is an opportunity to include large‐scale ecological planning in a newly launched 25‐year environment plan. 4.Policy implications. The concept of resilient ecological networks has attracted scientific and political support, but there is no consensus on what a resilient network would look like, or how to assess it. Therefore, it is unclear whether existing targets for action will be sufficient to achieve network resilience. We show that the scientific principles to place resilience and network theory at the heart of large‐scale and long‐term environmental planning are established and ready to implement in practice. Delivering a resilient network to support nature recovery is achievable and can be integrated with ongoing conservation actions and targets, by assessing their effectiveness on properties of the entire network. England's 25 Year Environment Plan promises to deliver a natural environment that is protected and enhanced for the future and so provides the ideal testbed

Do mangrove forest restoration or rehabilitation activities return biodiversity to pre-impact levels?

Background Mangrove forest restoration and rehabilitation programs are increasingly undertaken to re-establish ecosystem services in the context of community-based biodiversity conservation. Restoration is returning a habitat to the most natural condition, whereas rehabilitation often focuses on optimising ecosystem services alongside biodiversity. With many different restoration and rehabilitation objectives and techniques existing, it is difficult to assess the general effectiveness of restoration and rehabilitation on biodiversity and ecosystem services. This systematic review protocol presents a methodology that will be used to assess the impacts of mangrove forest restoration and rehabilitation on biodiversity and provisioning ecosystem services in a global context. Methods This review will assess studies that have undertaken biodiversity surveys of restored and rehabilitated mangrove forests by comparing them against suitable mature reference mangrove forests within the same region, or surveys prior to degradation of the forest. This review will investigate how the age and initial tree diversity of a restoration or rehabilitation activities determine the effectiveness of these initiatives. Taxa of commercial value to local communities will be assessed to identify whether rehabilitation for optimal ecosystem service provision is likely to conflict with the full restoration of mangrove forests

COVID-19: Analogues and lessons for tackling the extinction and climate crises

As environmental scientists working in countries whose COVID-linked deaths already exceed their military casualties from all campaigns since 1945, we believe there are significant messages from the handling of this horrific disease for efforts addressing the enormous challenges posed by the ongoing extinction and climate emergencies