Norman Myers

Biodiversity hotspots for conservation priorities

Conservationists are far from able to assist all species under threat, if only for lack of funding. This places a premium on priorities: how can we support the most species at the least cost? One way is to identify ‘biodiversity hotspots’ where exceptional concentrations of endemic species are undergoing exceptional loss of habitat. As many as 44% of all species of vascular plants and 35% of all species in four vertebrate groups are confined to 25 hotspots comprising only 1.4% of the land surface of the Earth. This opens the way for a ‘silver bullet’ strategy on the part of conservation planners, focusing on these hotspots in proportion to their share of the worlds species at risk.

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.

The biodiversity challenge: expanded hot-spots analysis.

SummaryThis paper aims to throw light on the mass extinction that is overtaking Earths species. Using an analytic methodology developed for an earlier partial assessment, it focuses on a series of ‘hot-spot’ areas, these being areas that (a) feature exceptional concentrations of species with high levels of endemism, and (b) face exceptional threats of destruction. The paper identifies another eight such areas, four of them in tropical forests and four in Mediterranean-type zones. The analysis reveals that the four tropical-forest areas contain at least 2,835 endemic plant species in 18,700 km2, or 1.1 percent of Earths plant species in 0.013 percent of Earths land surface; and that the four Mediterranean-type areas contain 12,720 endemic plan: species in 435,700 km2, or 5.1 percent of Earths plant species in 0.3 percent of the Earths land surface. Taken together, these eight hot-spot areas contain 15,555 endemic plant species in 454,400 km2, or 6.2 percent of Earths plant species in 0.3 percent of Earths land surface. This is to be compared with the earlier hot-spots analysis of 10 tropical-forest areas, with 34,400 endemic plant species in 292,000 km2, or 13.8 percent of Earths plant species in 0.2 percent of Earths land surface.Taking all 18 hot-spot areas together, we find they support 49,955 endemic plant species, or 20 percent of Earths plant species, in 746,400 km2, or 0.5 percent of Earths land surface. This means that one fifth of Earths plant species are confined to half of one percent of the Earths land surface — and they occur in habitats that are mostly threatened with imminent destruction.By concentrating on these hot-spot areas where needs are greatest and where the pay-off from safeguard measures would be greatest, conservationists can engage in a more systematised response to the challenge of large scale impending extinctions.

Environmental refugees in a globally warmed world

This paper examines the complex problem of environmental refugees as among the most serious of all the effects of global warming. Shoreline erosion, coastal flooding, and agricultural disruption from drought, soil erosion and desertification are factors now and in the future in creating a group of environmental refugees. Estimates are that at least 10 million such refugees exist today. A preliminary analysis is presented here as a first attempt to understand the full character and extent of the problem. Countries with large delta and coastal areas and large populations are at particular risk from sea-level rise of as little as .5 - 1 meter, compounded by storm surge and salt water intrusions. Bangladesh, Egypt, China, and India are discussed in detail along with Island states at risk. Other global warming effects such as shifts in monsoon systems and severe and persistent droughts make agriculture particularly vulnerable. Lack of soil moisture is during the growing season will probably be the primary problem. Additional and compounding environmental problems are discussed, and an overview of the economic, sociocultural and political consequences is given. 96 refs., 1 tab.

The biotic crisis and the future of evolution

The biotic crisis overtaking our planet is likely to precipitate a major extinction of species. That much is well known. Not so well known but probably more significant in the long term is that the crisis will surely disrupt and deplete certain basic processes of evolution, with consequences likely to persist for millions of years. Distinctive features of future evolution could include a homogenization of biotas, a proliferation of opportunistic species, a pest-and-weed ecology, an outburst of speciation among taxa that prosper in human-dominated ecosystems, a decline of biodisparity, an end to the speciation of large vertebrates, the depletion of “evolutionary powerhouses” in the tropics, and unpredictable emergent novelties. Despite this likelihood, we have only a rudimentary understanding of how we are altering the evolutionary future. As a result of our ignorance, conservation policies fail to reflect long-term evolutionary aspects of biodiversity loss.

Overcoming systemic roadblocks to sustainability: the evolutionary redesign of worldviews, institutions, and technologies.

A high and sustainable quality of life is a central goal for humanity. Our current socio-ecological regime and its set of interconnected worldviews, institutions, and technologies all support the goal of unlimited growth of material production and consumption as a proxy for quality of life. However, abundant evidence shows that, beyond a certain threshold, further material growth no longer significantly contributes to improvement in quality of life. Not only does further material growth not meet humanitys central goal, there is mounting evidence that it creates significant roadblocks to sustainability through increasing resource constraints (i.e., peak oil, water limitations) and sink constraints (i.e., climate disruption). Overcoming these roadblocks and creating a sustainable and desirable future will require an integrated, systems level redesign of our socio-ecological regime focused explicitly and directly on the goal of sustainable quality of life rather than the proxy of unlimited material growth. This transition, like all cultural transitions, will occur through an evolutionary process, but one that we, to a certain extent, can control and direct. We suggest an integrated set of worldviews, institutions, and technologies to stimulate and seed this evolutionary redesign of the current socio-ecological regime to achieve global sustainability.

How can a knowledge of the past help to conserve the future? Biodiversity conservation and the relevance of long-term ecological studies

This paper evaluates how long-term records could and should be utilized in conservation policy and practice. Traditionally, there has been an extremely limited use of long-term ecological records (greater than 50 years) in biodiversity conservation. There are a number of reasons why such records tend to be discounted, including a perception of poor scale of resolution in both time and space, and the lack of accessibility of long temporal records to non-specialists. Probably more important, however, is the perception that even if suitable temporal records are available, their roles are purely descriptive, simply demonstrating what has occurred before in Earths history, and are of little use in the actual practice of conservation. This paper asks why this is the case and whether there is a place for the temporal record in conservation management. Key conservation initiatives related to extinctions, identification of regions of greatest diversity/threat, climate change and biological invasions are addressed. Examples of how a temporal record can add information that is of direct practicable applicability to these issues are highlighted. These include (i) the identification of species at the end of their evolutionary lifespan and therefore most at risk from extinction, (ii) the setting of realistic goals and targets for conservation ‘hotspots’, and (iii) the identification of various management tools for the maintenance/restoration of a desired biological state. For climate change conservation strategies, the use of long-term ecological records in testing the predictive power of species envelope models is highlighted, along with the potential of fossil records to examine the impact of sea-level rise. It is also argued that a long-term perspective is essential for the management of biological invasions, not least in determining when an invasive is not an invasive. The paper concludes that often inclusion of a long-term ecological perspective can provide a more scientifically defensible basis for conservation decisions than the one based only on contemporary records. The pivotal issue of this paper is not whether long-term records are of interest to conservation biologists, but how they can actually be utilized in conservation practice and policy.

Biodiversity hotspots house most undiscovered plant species

For most organisms, the number of described species considerably underestimates how many exist. This is itself a problem and causes secondary complications given present high rates of species extinction. Known numbers of flowering plants form the basis of biodiversity “hotspots”—places where high levels of endemism and habitat loss coincide to produce high extinction rates. How different would conservation priorities be if the catalog were complete? Approximately 15% more species of flowering plant are likely still undiscovered. They are almost certainly rare, and depending on where they live, suffer high risks of extinction from habitat loss and global climate disruption. By using a model that incorporates taxonomic effort over time, regions predicted to contain large numbers of undiscovered species are already conservation priorities. Our results leave global conservation priorities more or less intact, but suggest considerably higher levels of species imperilment than previously acknowledged.

Population, environment, and development

The strategies for reducing population growth include social development and improvement in the educational attainment of women. The decline in Kenyas growth rate was attributed to high female literacy and reduced infant mortality. Another strategy for enhancing fertility decline is to reduce child mortality, particularly from preventable causes such as diarrhea. The entire cost of such a strategy to reduce preventable disease would be about

Tropical forests: much more than stocks of wood

1.33 per 300 million taxpayers in developed countries. Family planning services must be expanded. Prevention of maternal mortality and AIDS would bring major benefits. Strategies for environmental protection emphasized the already existing plan of action set out in the UNCED document Agenda 21 in Rio de Janeiro. The plan has suffered from inaction. The estimated cost of