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Global biodiversity outlook 31

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The 2010 biodiversity target has not been met at the global level. None of the twenty-one sub-targets accompanying the overall target of significantly reducing the rate of biodiversity loss by 2010 can be said definitively to have been achieved globally, although some have been partially or locally achieved. Despite an increase in conservation efforts, the state of biodiversity continues to decline, according to most indicators, largely because the pressures on biodiversity continue to increase. There is no indication of a significant reduction in the rate of decline in biodiversity, nor of a significant reduction in pressures upon it. However, negative trends have been slowed or reversed in some ecosystems. There are several indications that responses to biodiversity loss are increasing and improving, although not yet on a scale sufficient to affect overall negative trends in the state of biodiversity or the pressures upon it.
When governments agreed to the 2010 target for significantly reducing the rate of biodiversity loss [See Box 1], a number of tools were put in place within the Convention on Biological Diversity and other conventions to help focus action towards achieving the target, to monitor progress towards it, and eventually to determine whether it had in fact been achieved11. Twenty-one sub-targets were defined, to be reached by 2010 towards eleven principal goals related to biodiversity12.
While none of the sub-targets can be said definitively to have been met, some have been achieved partially or at regional or national scales [See Table 1]. In fact, the 2010 biodiversity target has inspired action at many levels. Some 170 countries now have national biodiversity strategies and action plans [See Box 2 and Figure 1]. Protected areas have been expanded in number and extent, on both land and in coastal waters. Environmental impact assessment is more widely applied with most countries reporting that they have some measures in place for its use.13
Most countries are also undertaking activities related to communication, education and public awareness as well biodiversity monitoring, research and the development of databases. At the international level, financial resources have been mobilized and progress has been made in developing mechanisms for research, monitoring and scientific assessment of biodiversity.
There is no single measurement that captures the current status or trends in global biodiversity. Therefore a range of indicators was developed for the Convention on Biological Diversity, to provide scientifically rigorous assessments of trends in the state of the various components of biodiversity (genes, populations, species, ecosystems); the pressures being imposed upon it; and the responses being adopted to address biodiversity loss14,15,16,17,18,19,20. Ten of the fifteen headline indicators show trends unfavourable for biodiversity [See Table 2]. Yet, for certain indicators the amount and coverage of data is not sufficient to make statements with confidence. The assessment of status and trends of biodiversity on the following pages therefore relies on multiple lines of evidence, including scientific literature and recent assessments21, as well as national reports from the Parties to the Convention. Not a single government in the latest reports submitted to the CBD claims that the 2010 biodiversity target has been completely met at the national level22. Around one in five governments state explicitly that they have missed the target.
Although the evidence does not show a significant decline in the rate of biodiversity loss, some interventions have had a measurable, positive impact by making the decline less severe than it would otherwise have been. For example, it is estimated that 31 bird species, out of a total of some 9,800, would have become extinct in the absence of conservation actions23.

Box 2: National action on biodiversity
Over 170 countries (87% of the Parties to the Convention) have developed national biodiversity strategies and action plans (NBSAPs). A further 14 Parties are preparing them, and 9 have either not started to draw up a strategy or had not announced their intention to do so by the time this Outlook went to press24.
An overwhelming majority of governments, in other words, have been through the process of codifying their approach to protecting the biodiversity within their own territory. In many countries, the preparation of strategies has stimulated the development of additional laws and programmes, and spurred action on a broad range of issues, including: the eradication or control of alien invasive species; using biodiversity sustainably; the protection of traditional knowledge and rules to ensure local communities share benefits from bio-prospecting which might result in patents or sales of new drugs, foods or cosmetics; the safe use of biotechnology; and maintaining the diversity of plants and animals used in agriculture.
Relatively few Parties have fully integrated the 2010 biodiversity target into their national strategies. Moreover, few countries are using NBSAPs as effective tools for integrating biodiversity into broader national strategies, policies and planning processes. More than 80% of Parties, in their latest national reports to the CBD, concede that limited biodiversity mainstreaming, fragmented decision making and/or limited communication among government ministries or sectors is a challenge to meeting the goals of the Convention.
However, recently developed and updated national biodiversity strategies tend to be more strategic than the first generation of NBSAPs, they have a stronger emphasis on mainstreaming, and give greater recognition to broader national development objectives25.
NBSAPs should catalyze a number of strategic actions in countries, including:

  • Mainstreaming – biodiversity will be best protected if it is a significant factor in decisions made across a wide range of sectors, departments and economic activities, systems for planning the use of land, freshwater and sea areas (spatial planning), and policies to reduce poverty and adapt to climate change.

  • Communication and involvement – strategies will only be effective if they genuinely involve the people closest to the resources they are designed to protect. Often the best solutions will be driven by local demand, using legal and institutional frameworks set at a higher level.

  • Tools for implementation – particular approaches, such as making integrated decisions based on maintaining and improving the overall health of ecosystems, or introducing policies on payments for the use of hitherto “free” ecosystem services, can aid in the protection of biodiversity.

  • Knowledge – for good decisions to be made, the best available information about the biodiversity of a country or region must be accessible to the right people at the right time. The Clearing-House Mechanism, a system of compiling, co-ordinating and providing access to relevant and up-to-date knowledge, is a key tool provided by the CBD framework.

  • Monitoring – assessing and communicating progress towards the objectives and targets set by a biodiversity strategy is an important way to improve its effectiveness and visibility.

  • Financing and capacity – co-ordinating action to support biodiversity will only be meaningful if there is money to do it and there are people who know how to do it.

Missing the 2010 target has serious implications for human societies. Biodiversity underpins a wide range of services that support economies, food production systems and secure living conditions [See Box 3]. The loss of biodiversity (at the genetic, species and ecosystem levels) also affects human health in many ways.

Projections of the impacts of continued biodiversity loss, some associated costs and how they might be avoided, are outlined in this synthesis. First, the current status and trends of biodiversity, the pressures upon it and responses to its loss are described in more detail.

Box 3: Why biodiversity matters
Biodiversity is the variation that exists not just between the species of plants, animals, micro-organisms and other forms of life on the planet – but also within species, in the form of genetic diversity, and at the level of ecosystems in which species interact with one another and with the physical environment.
This diversity is of vital importance to people, because it underpins a wide range of ecosystem services on which human societies have always depended, although their importance has often been greatly undervalued or ignored26,27. When elements of biodiversity are lost, ecosystems become less resilient and their services threatened. More homogeneous, less varied landscapes or aquatic environments are often more vulnerable to sudden external pressures such as disease and climatic extremes.
Ecosystem services can be divided into four categories28:

  • provisioning services, or the supply of goods of direct benefit to people, and often with a clear monetary value, such as timber from forests, medicinal plants, and fish from the oceans, rivers and lakes;

  • regulating services, the range of vital functions carried out by ecosystems which are rarely given a monetary value in conventional markets. They include regulation of climate through the storing of carbon and control of local rainfall, the removal of pollutants by filtering the air and water, and protection from disasters such as landslides and coastal storms;

  • cultural services, not providing direct material benefits, but contributing to wider needs and desires of society, and therefore to people’s willingness to pay for conservation. They include the spiritual value attached to particular ecosystems such as sacred groves, and the aesthetic beauty of landscapes or coastal formations that attract tourists; and

  • supporting services, not of direct benefit to people but essential to the functioning of ecosystems and therefore indirectly responsible for all other services. Examples are the formation of soils and the processes of plant growth.

Species populations and extinction risks
The population of wild vertebrate species fell by an average of nearly one- third (31%) globally between 1970 and 2006, with the decline especially severe in the tropics (59%) and in freshwater ecosystems (41%).
Trends in the average size of species populations, as measured by the Living Planet Index (LPI), vary greatly between temperate and tropical regions, and between types of species [See Figure 2]. Temperate species populations actually increased on average since 1970, and the steady global decline since that date is accounted for entirely by a sharp fall in the tropics. This does not necessarily mean tropical biodiversity is in a worse state than in temperate regions: if the index were to extend back centuries rather than decades, populations of temperate species may have declined by an equal or greater amount. Moreover, the increase in wild animal populations in temperate regions may be linked to widespread afforestation of former cropland and pasture, and does not necessarily reflect richer diversity of species. However, the current rates of decline in global species abundance represent a severe and ongoing loss of biodiversity in tropical ecosystems29,30,31.
Observed trends in populations of wild species include:

  • Farmland bird populations in Europe have declined by on average about 50% since 1980.

  • Bird populations in North American grasslands declined by nearly 40% between 1968 and 2003, showing a slight recovery over the past five years; those in North American drylands have declined by nearly 30% since the late 1960s.

  • Of the 1,200 waterbird populations with known trends, 44% are in decline.

  • 42% of all amphibian species and 40% of bird species are declining in population.

Species in all groups with known trends are, on average, being driven closer to extinction, with amphibians facing the greatest risk and warm water reef-building corals showing the most rapid deterioration in status. Among selected vertebrate, invertebrate and plant groups, between 12% and 55% of species are currently threatened with extinction. Species of birds and mammals used for food and medicine are on average facing a greater extinction risk than those not used for such purposes. Preliminary assessments suggest that 23% of plant species are threatened.
Conservation interventions have reduced the extinction risk for some species, but they are outnumbered by those species that are moving closer towards extinction32,33,34. The Red List Index (RLI), which tracks the average extinction risk of species over time, shows that all groups that have been fully assessed for extinction risk are becoming more threatened35,36,3738,39. [See Box 4 and Figures 3, 440 and 5]
The most severe recent increase in extinction risk has been observed among coral species, probably due in large part to the widespread bleaching of tropical reef systems in 1998, a year of exceptionally-high sea temperatures. Amphibians are on average the group most threatened with extinction, due to a combination of habitat modification, changes in climate and the fungal disease chytridiomycosis.41

Box 4: How extinction risk is assessed
The IUCN Red list categories reflect the likelihood that a species may become extinct if current conditions persist. The risk status of species is based on information generated from the work of thousands of species scientists from around the world.42
Assessments follow a rigorous system which classifies species into one of eight categories: Extinct, Extinct in the Wild, Critically Endangered, Endangered, Vulnerable, Near Threatened, Least Concern and Data Deficient. Those species that are classified as Critically Endangered, Endangered or Vulnerable are considered to be threatened.
Species are assigned to categories of extinction risk using criteria with quantitative thresholds for population size and structure, rate of population decline, range size and structure, and extinction risk as determined by modeling of population viability.
As of 2009, 47,677 species had been assessed and of these 36% are considered threatened with extinction43; while of the 25,485 species in completely assessed groups (mammals, birds, amphibians, corals, freshwater crabs, cycads and conifers) 21% are considered threatened. Of 12,055 plant species assessed, 70% are threatened44. However, plant species with a higher average extinction risk are over-represented in this sample.

Regional trends regarding the extinction risk of species include45:

  • Bird species have faced an especially steep increase in extinction risk in South-East Asia, on the Pacific Islands, polar regions and in marine and coastal ecosystems.

  • Mammals have also suffered the steepest increase in risk of extinction in South and South-East Asia, due to the combined impact of hunting and loss of habitat. Between ecosystem types, marine mammals have faced the steepest increase in risk, although freshwater mammals remain the most threatened.

  • Amphibians have deteriorated in status fastest, and are in absolute terms at greatest risk of extinction, in South and Central America and the Caribbean.

Species of birds and mammals used for food and medicines are on average facing a greater extinction risk than species as a whole, through a combination of over-exploitation, habitat loss and other factors. Species of bird, mammal and amphibians that are exploited for food and medicines are also moving more quickly into a higher risk category46. This emphasizes the threat posed by biodiversity loss to the health and well-being of millions of people directly dependent on the availability of wild species47,48 . For example the World Health Organization has estimated that 60% of children suffering from fever in Ghana, Mali, Nigeria and Zambia are treated at home with herbal medicines49 while in one part of Nepal, 450 plant species are commonly used locally for medicinal purposes50.
Globally some 80 per cent of people in developing countries rely on traditional medicines, the majority of which are derived from plants51,52,53. Although global data for plants are not available, medicinal plants face a high risk of extinction in those parts of the world where people are most dependent on them for health care and income from wild collection – namely Africa, Asia, the Pacific and South America [See Figure 6].
Terrestrial ecosystems
Tropical forests continue to be lost at a rapid rate, although deforestation has recently slowed in some countries. Net loss of forests has slowed substantially in the past decade, largely due to forest expansion in temperate regions.
The best information on terrestrial habitats relates to forests, which currently occupy approximately 31 per cent of the Earth’s land surface. Forests are estimated to contain more than half of terrestrial animal and plant species, the great majority of them in the tropics, and account for more than two-thirds of net primary production on land – the conversion of solar energy into plant matter.
Deforestation, mainly conversion of forests to agricultural land, is showing signs of decreasing in several tropical countries [See Box 5 and Figure 7], but continues at an alarmingly high rate. Just under 130,000 square kilometres of forest were converted to other uses or lost through natural causes each year from 2000 to 2010, compared to nearly 160,000 square kilometres per year in the 1990s. The net loss of forests has slowed substantially, from approximately 83,000 square kilometres per year in the 1990s to just over 50,000 square kilometres per year from 2000-2010. This is mainly due to large-scale planting of forests in temperate regions and to natural expansion of forests. Since newly-planted forests often have low biodiversity value and may only include a single tree species, a slowing of net forest loss does not necessarily imply a slowing in the loss of global forest biodiversity. Between 2000 and 2010, the global extent of primary forest ( that is, substantially undisturbed) declined by more than 400,000 square kilometres, an area larger than Zimbabwe54.

South America and Africa continued to have the largest net loss of forests in 2000-2010. Oceania also reported a net loss of forests, while the area of forest in North and Central America (treated as a single region) was estimated to be almost the same in 2010 as in 2000. The forest area in Europe continued to expand, although at a slower rate than in the 1990s. Asia, which had a net loss in the 1990s, reported a net gain of forests in the period 2000–2010, primarily due to large-scale afforestation reported by China, and despite continued high rates of net loss of forests in many countries in South and Southeast Asia55.

Box 5: The Brazilian Amazon – a slowing trend for deforestation
The most recent satellite data suggest that annual deforestation of the Brazilian portion of the Amazon has slowed significantly, from a peak of more than 27,000 square kilometres in 2003-4 to just over 7,000 square kilometres in 2008-9, a decrease of over 74 per cent56. However, the same satellite images indicate that a growing area of the Amazon forest is becoming degraded. The 2008-9 deforestation figure, the lowest since satellite monitoring began in 1988, may have been influenced by the economic recession, as well as by actions taken by the government, private sector and civil society organizations to control deforestation; but the average from 2006-9 was more than 40 per cent below the average for the previous decade, indicating a significant slowing of the trend57,58. Cumulative deforestation of the Brazilian Amazon is nevertheless substantial, reaching more than 17 per cent of the original forest area, and even achievement of the existing government target of an 80 per cent reduction in annual deforestation by 2020 (from the 1996-2005 average) would bring the cumulative loss of forest to nearly 20 per cent.59 According to a recent study co-ordinated by the World Bank, 20% Amazon deforestation would be sufficient to trigger significant dieback of forest in some parts of the biome by 2025, when coupled with other pressures such as climate change and forest fires.
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