Publications - Indicators and Assessments

Wildlife Comeback in Europe report
Wildlife comeback in Europe: The recovery of selected mammal and bird species

This study seeks to identify the main drivers for recovery of a selected number of mammal and bird species in Europe, in order to learn lessons for the future.


About this report
This report on the resurgence of European wildlife was produced by the Zoological Society of London, BirdLife International and the European Bird Census Council (EBCC) for the Rewilding Europe Initiative. It shows that a wide-ranging comeback of iconic species has taken place in many regions across the continent over the past 50 years. Legal protection of species and sites emerged as one of the main reasons behind this recovery, while active reintroductions and re-stockings have also been important factors. Whilst this suggests that nature conservation works, more commitment, resources and new kinds of conservation measures are needed in order to halt biodiversity loss and restore other declining and depleted species.

Download: Wildlife Comeback in Europe report (19.81 MB)

Spineless: status and trends of the world’s invertebrates

The Spineless report brings together the work of thousands of scientists through the IUCN Red List, to look at the pressures on the environment and how invertebrates are being affected.

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About this report
This report contains the most comprehensive assessment of the status and trends of the world’s invertebrates conducted to date. It introduces the staggering diversity of invertebrates, ranging from microscopic zooplankton to giant squid. Together these organisms represent around 80% of the known species on our planet. They not only provide a bewilderingly rich and varied component of the natural world, they are our natural capital; the engineers of the many benefits which humans accrue from an intact and fully functioning environment. This report documents several reasons for concern about the health of invertebrates.

Living Planet Index for Africa

The Africa Living Planet Index shows a 39% reduction in the size of vertebrate animal populations between 1970 and 2008 in Africa.


About this report
This report on the state of biodiversity and resource use in Africa offers a broader view than that offered by the results produced by the Living Planet Index alone. It looks at natural resource use within Africa and how the rate of use of resources such as water and natural capital have changed over the past forty years. For example, the Ecological Footprint of all African countries increased by 240% between 1961 and 2008, which is likely due to a combination of population growth and increased consumption per capita. It also presents examples of solutions that promote the creation of wealth and alleviation of poverty through more sustainable management of the continent's natural capital.

Tracking trends in Arctic marine populations

The Arctic Species Trend Index for marine animals shows an increase in abundance between 1970 and 2007. This trend seems likely to be driven by increases in the number of fish in the Bering sea.


About this report
This report into trends in abundance of marine Arctic species looks initially at the overall increasing trend that can be observed. It then breaks this trend down regionally and taxonomically to establish that the overall increase in abundance is different in these subdivisions. We see, for example, that although bird populations increased in abundance substantially until 1986, growth since then has been much more limited. Ecological and management factors are also considered; for example, how changing patterns in sea ice and protected areas can influence trends in population abundance.

The Living Planet Report 2012

The Living Planet Index shows that global vertebrate populations have declined by 30% since 1970 with a more worrying decline of 60% if only the tropics are considered.


About this report
The 2012 Living Planet Report describes alarming trends both in terms of global biodiversity and the global ecological footprint, amongst other indicators. Global biodiversity is measured using the Living Planet Index (LPI), which describes trends in vertebrate populations. The global ecological footprint index measures the area of biologically productive land and water required to provide the renewable resources that people use, for example, agriculture and carbon sequestration. The world population is currently using resources at a rate equivalent to what one and a half earths could supply, a trend which only seems likely to increase

The Arctic Species Trend Index 2011

This update of the Arctic Species Trend Index suggests that the average abundance of Arctic vertebrates increased from 1970 until 1990 and since then has remained fairly stable.


About this report
This report provides an update on the conclusions drawn in the Arctic Species Trend Index report published in 2010, which suggested that the abundance of Arctic vertebrates increased between 1970 and 1990 and thereafter remained fairly stable. When abundance is grouped taxonomically or into broad ecozones, a different pattern is seen with distinct trends emerging for different regions and clades. It goes on to summarise the key results of a spatial analysis performed on this data and on marine vertebrates. The spatial analyses have allowed conclusions to be drawn about biodiversity change over space and time relating to other environmental factors as well as providing an opportunity to identify data gaps. The marine analysis, meanwhile, has allowed distinct patterns in different taxanomic groups to be identified, for example since the late 1980's marine mammal abundance has largely declined whilst marine fish populations have stabilised.

Tracking trends in Arctic vertebrate populations through space and time

This report which analysed Arctic Species Trend Index data from a spatial perspective showed that the proportion of locations with increasing or stable populations has declined since the 1960’s. This could reflect a focus on declining populations in recent data collection efforts or widespread decline in Arctic vertebrate populations.


About this report
This report looked at the Arctic Species Trend Index data, updated from 2010, using spatial analysis techniques to examine broad-scale patterns of biodiversity change across the Arctic. These patterns were looked at in relation to climatic and other environmental data to investigate potential causes of biodiversity change. At a regional level spatial analysis revealed clusters of population growth and decline, for example increases in the Bering Sea and declining fish stocks in the Labrador Sea. This spatial approach was also used to identify gaps in data coverage with a view to finding new data sources and setting up new monitoring programmes to fill the gaps. This report used ordinary least squares and geographically weighted regression to analyse spatial trends and used the results of these analyses to make recommendations.

Biodiversity. Global Environmental Outlook 5

This review chapter addresses the key issues surrounding the conservation of global biodiversity today.

About this report
This chapter presents the globally agreed indicators and targets set out for the preservation of biodiversity. It then goes on to discuss the potential implications for human well being if these targets are not met and summarises our understanding of the key pressures on biodiversity at the current time. In doing so it also lays out the ways in which biodiversity is valuable to humans in terms of issues such as health and climate change before going on to discuss the management of different elements of biodiversity and the variety of ways in which the targets set out initially may be achieved.

Wildlife Comeback in Europe: An overview of changes in abundance and distribution of selected wildlife species in Europe for the period 1960-2010

This report looks at the dynamic changes in patterns of distribution of European wildlife comeback over the past 50 years. The broadest scale analysis in this report showed that between 1960 and 2010 range sizes have increased by 20% on average for the 106 species analysed.


About this report
This report looks at trends in wildlife comeback in Europe through the lens of territory expansion or recolonisation and population growth. Analysis was carried out at several scales. A small group of 20 species of bird and mammal were examined in detail; the changing pattern of their range sizes and conservation history were considered to assess success of management strategies and identify areas for improvement. The report suggests that the strongest comebacks do seem to have been driven by management interventions, such as cessation of exploitation. Comebacks, such as those described in this report, are important as they may provide an evidence base that can be applied for wider success of management of species for conservation. A further analysis of 25 species was carried out, some showing range expansions and others contractions, highlighting the need for effective conservation strategies. A broader analysis of 106 species' range size and population abundance time series data was carried out, revealing an average 20% increase in range size. It should be noted, however, that an increase in range size does not neccesarily indicate that a species is fully recovered. Trophic level, body size and location of populations were also given a consideration, for example declines seem to be clustered in Southern Europe. The report also considered how to go about analysing fossil and historical records to assess abundance.



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  • Zamin T, Baillie JEM, Miller R, Rodriguez JP, Ardid A, & Collen B. (2010) National Red Listing Beyond the 2010 Target.Conservation Biology, 24(4): 1012-1020
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