Jonathan Loh

Tracking the ecological overshoot of the human economy

Sustainability requires living within the regenerative capacity of the biosphere. In an attempt to measure the extent to which humanity satisfies this requirement, we use existing data to translate human demand on the environment into the area required for the production of food and other goods, together with the absorption of wastes. Our accounts indicate that human demand may well have exceeded the biospheres regenerative capacity since the 1980s. According to this preliminary and exploratory assessment, humanitys load corresponded to 70% of the capacity of the global biosphere in 1961, and grew to 120% in 1999.

A mid-term analysis of progress toward international biodiversity targets

In 2010, the international community, under the auspices of the Convention on Biological Diversity, agreed on 20 biodiversity-related “Aichi Targets” to be achieved within a decade. We provide a comprehensive mid-term assessment of progress toward these global targets using 55 indicator data sets. We projected indicator trends to 2020 using an adaptive statistical framework that incorporated the specific properties of individual time series. On current trajectories, results suggest that despite accelerating policy and management responses to the biodiversity crisis, the impacts of these efforts are unlikely to be reflected in improved trends in the state of biodiversity by 2020. We highlight areas of societal endeavor requiring additional efforts to achieve the Aichi Targets, and provide a baseline against which to assess future progress. Although conservation efforts are accelerating, their impact is unlikely to improve the global state of biodiversity by 2020. Indicators of progress and decline The targets set by the Convention on Biological Diversity in 2010 focused international efforts to alleviate global biodiversity decline. However, many of the consequences of these efforts will not be evident by the 2020 deadline agreed to by governments of 150 countries. Tittensor et al. analyzed data on 55 different biodiversity indicators to predict progress toward the 2020 targets—indicators such as protected area coverage, land-use trends, and endangered species status. The analysis pinpoints the problems and areas that will need the most attention in the next few years. Science, this issue p. 241

The Living Planet Index: using species population time series to track trends in biodiversity

The Living Planet Index was developed to measure the changing state of the worlds biodiversity over time. It uses time-series data to calculate average rates of change in a large number of populations of terrestrial, freshwater and marine vertebrate species. The dataset contains about 3000 population time series for over 1100 species. Two methods of calculating the index are outlined: the chain method and a method based on linear modelling of log-transformed data. The dataset is analysed to compare the relative representation of biogeographic realms, ecoregional biomes, threat status and taxonomic groups among species contributing to the index. The two methods show very similar results: terrestrial species declined on average by 25% from 1970 to 2000. Birds and mammals are over-represented in comparison with other vertebrate classes, and temperate species are over-represented compared with tropical species, but there is little difference in representation between threatened and non-threatened species. Some of the problems arising from over-representation are reduced by the way in which the index is calculated. It may be possible to reduce this further by post-stratification and weighting, but new information would first need to be collected for data-poor classes, realms and biomes.

Monitoring change in vertebrate abundance: the living planet index.

The task of measuring the decline of global biodiversity and instituting changes to halt and reverse this downturn has been taken up in response to the Convention on Biological Diversitys 2010 target. It is an undertaking made more difficult by the complex nature of biodiversity and the consequent difficulty in accurately gauging its depletion. In the Living Planet Index, aggregated population trends among vertebrate species indicate the rate of change in the status of biodiversity, and this index can be used to address the question of whether or not the 2010 target has been achieved. We investigated the use of generalized additive models in aggregating large quantities of population trend data, evaluated potential bias that results from collation of existing trends, and explored the feasibility of disaggregating the data (e.g., geographically, taxonomically, regionally, and by thematic area). Our results show strengths in length and completeness of data, little evidence of bias toward threatened species, and the possibility of disaggregation into meaningful subsets. Limitations of the data set are still apparent, in particular the dominance of bird data and gaps in tropical-species population coverage. Population-trend data complement the longer-term, but more coarse-grained, perspectives gained by evaluating species-level extinction rates. To measure progress toward the 2010 target, indicators must be adapted and strategically supplemented with existing data to generate meaningful indicators in time. Beyond 2010, it is critical a strategy be set out for the future development of indicators that will deal with existing data gaps and that is intricately tied to the goals of future biodiversity targets.

Shrink and share: humanity's present and future Ecological Footprint

Sustainability is the possibility of all people living rewarding lives within the means of nature. Despite ample recognition of the importance of achieving sustainable development, exemplified by the Rio Declaration of 1992 and the United Nations Millennium Development Goals, the global economy fails to meet the most fundamental minimum condition for sustainability—that human demand for ecosystem goods and services remains within the biospheres total capacity. In 2002, humanity operated in a state of overshoot, demanding over 20% more biological capacity than the Earths ecosystems could regenerate in that year. Using the Ecological Footprint as an accounting tool, we propose and discuss three possible global scenarios for the future of human demand and ecosystem supply. Bringing humanity out of overshoot and onto a potentially sustainable path will require managing the consumption of food, fibre and energy, and maintaining or increasing the productivity of natural and agricultural ecosystems.

The Why, What, and How of Global Biodiversity Indicators Beyond the 2010 Target

The 2010 biodiversity target agreed by signatories to the Convention on Biological Diversity directed the attention of conservation professionals toward the development of indicators with which to measure changes in biological diversity at the global scale. We considered why global biodiversity indicators are needed, what characteristics successful global indicators have, and how existing indicators perform. Because monitoring could absorb a large proportion of funds available for conservation, we believe indicators should be linked explicitly to monitoring objectives and decisions about which monitoring schemes deserve funding should be informed by predictions of the value of such schemes to decision making. We suggest that raising awareness among the public and policy makers, auditing management actions, and informing policy choices are the most important global monitoring objectives. Using four well-developed indicators of biological diversity (extent of forests, coverage of protected areas, Living Planet Index, Red List Index) as examples, we analyzed the characteristics needed for indicators to meet these objectives. We recommend that conservation professionals improve on existing indicators by eliminating spatial biases in data availability, fill gaps in information about ecosystems other than forests, and improve understanding of the way indicators respond to policy changes. Monitoring is not an end in itself, and we believe it is vital that the ultimate objectives of global monitoring of biological diversity inform development of new indicators.

Predicting how populations decline to extinction

Global species extinction typically represents the endpoint in a long sequence of population declines and local extinctions. In comparative studies of extinction risk of contemporary mammalian species, there appear to be some universal traits that may predispose taxa to an elevated risk of extinction. In local population-level studies, there are limited insights into the process of population decline and extinction. Moreover, there is still little appreciation of how local processes scale up to global patterns. Advancing the understanding of factors which predispose populations to rapid declines will benefit proactive conservation and may allow us to target at-risk populations as well as at-risk species. Here, we take mammalian population trend data from the largest repository of population abundance trends, and combine it with the PanTHERIA database on mammal traits to answer the question: what factors can be used to predict decline in mammalian abundance? We find in general that environmental variables are better determinants of cross-species population-level decline than intrinsic biological traits. For effective conservation, we must not only describe which species are at risk and why, but also prescribe ways to counteract this.

Overcoming the challenges to conservation monitoring: integrating data from in-situ reporting and global data sets to measure impact and performance

If parties to the Convention on Biological Diversity (CBD) and their partners are to report effectively on progress against national, regional and global biodiversity conservation goals, data will need to be collected at multiple levels. Global data sets, many gathered using remote sensing, offer partial solutions but need to be complemented by field-level observations to provide the resolution necessary to track conservation measures in a meaningful way. This paper summarises efforts made by the conservation organisation WWF, working with partners, to integrate 10 indicators of relevance to CBD parties into its global monitoring system and to use global data sets and data from field programmes to determine progress against multi-level goals and to assess programme performance and impacts. Integration of in-situ and ex-situ data into reporting dashboards tailored to WWF’s needs allowed some degree of assessment of progress and adaptive management of the programme portfolio. Indicator trends were most favourable (on track) for protected area (PA) coverage and market share of sustainable commodities, and least favourable (worsening) for species offtake, species populations, wildlife trade, habitat fragmentation and Ecological Footprint. The most useful indicators – which could be disaggregated to provide trends at local levels relevant to WWF field programmes – were species populations, habitat cover and fragmentation, PA coverage and PA management effectiveness. However challenges remain if local and global monitoring objectives are to be aligned, including the need for increased collection of data by field projects, improved harmonisation of indicators, and greater sharing of data in formats of use to practitioners. We advocate wider adoption by governments and civil society organisations of indicators with the dual function of tracking delivery of CBD Aichi Targets as well as monitoring national, regional and ecoregional level conservation programmes, and urge more NGOs and academic bodies to support capacity building and data collection.