Eric W. Sanderson

The Human Footprint and the Last of the Wild

I Genesis, God blesses human beings and bids us to take dominion over the fish in the sea, the birds in the air, and every other living thing. We are entreated to be fruitful and multiply, to fill the earth, and subdue it (Gen. 1:28). The bad news, and the good news, is that we have almost succeeded. There is little debate in scientific circles about the importance of human influence on ecosystems. According to scientists’ reports, we appropriate over 40% of the net primary productivity (the green material) produced on Earth each year (Vitousek et al. 1986, Rojstaczer et al. 2001). We consume 35% of the productivity of the oceanic shelf (Pauly and Christensen 1995), and we use 60% of freshwater run-off (Postel et al. 1996). The unprecedented escalation in both human population and consumption in the 20th century has resulted in environmental crises never before encountered in the history of humankind and the world (McNeill 2000). E. O. Wilson (2002) claims it would now take four Earths to meet the consumption demands of the current human population, if every human consumed at the level of the average US inhabitant. The influence of human beings on the planet has become so pervasive that it is hard to find adults in any country who have not seen the environment around them reduced in natural values during their lifetimes—woodlots converted to agriculture, agricultural lands converted to suburban development, suburban development converted to urban areas. The cumulative effect of these many local changes is the global phenomenon of human influence on nature, a new geological epoch some call the “anthropocene” (Steffen and Tyson 2001). Human influence is arguably the most important factor affecting life of all kinds in today’s world (Lande 1998, Terborgh 1999, Pimm 2001, UNEP 2001). Yet despite the broad consensus among biologists about the importance of human influence on nature, this phenomenon and its implications are not fully appreciated by the larger human community, which does not recognize them in its economic systems (Hall et al. 2001) or in most of its political decisions (Soulé and Terborgh 1999, Chapin et al. 2000). In part, this lack of appreciation may be due to scientists’ propensity to express themselves in terms like “appropriation of net primary productivity” or “exponential population growth,” abstractions that require some training to understand. It may be due to historical assumptions about and habits inherited from times when human beings, as a group, had dramatically less influence on the biosphere. Now the individual deci-

A conceptual model for conservation planning based on landscape species requirements

Effective conservation planning requires, considering all the complicated biological, social and economic factors which impinge on the ecological integrity of a site, and then focusing inevitably limited conservation resources on those times, places and activities that most impact ecological structure and function. The landscape species concept provides a useful lens for defining conservation landscapes and highlighting potential threats from human activity. This paper outlines a conceptual methodology for landscape conservation being tested by the Wildlife Conservation Society at three sites in Latin America and Africa. Based on the biological requirements of an ecologically functioning population of a landscape species, the “biological” landscape is defined. This landscape is compared to the landscape of human activities through the use of Geographic Information Systems (GIS). Focal landscapes sufficient to meet species requirements are defined and threats from human activity evaluated with respect to biological requirements. A suite of landscape species may be selected depending on resources, leading to multiple, often overlapping, focal landscapes. A hypothetical example is presented.

Sixteen years of change in the global terrestrial human footprint and implications for biodiversity conservation

Human pressures on the environment are changing spatially and temporally, with profound implications for the planets biodiversity and human economies. Here we use recently available data on infrastructure, land cover and human access into natural areas to construct a globally standardized measure of the cumulative human footprint on the terrestrial environment at 1 km2 resolution from 1993 to 2009. We note that while the human population has increased by 23% and the world economy has grown 153%, the human footprint has increased by just 9%. Still, 75% the planets land surface is experiencing measurable human pressures. Moreover, pressures are perversely intense, widespread and rapidly intensifying in places with high biodiversity. Encouragingly, we discover decreases in environmental pressures in the wealthiest countries and those with strong control of corruption. Clearly the human footprint on Earth is changing, yet there are still opportunities for conservation gains.

What Does It Mean to Successfully Conserve a (Vertebrate) Species

The conservation of species is one of the foundations of conservation biology. Successful species conservation has often been defined as simply the avoidance of extinction. We argue that this focus, although important, amounts to practicing conservation at the “emergency room door,” and will never be a sufficient approach to conserving species. Instead, we elaborate a positive definition of species conservation on the basis of six attributes and propose a categorization of different states of species conservation using the extent of human management and the degree to which each of the attributes is conserved. These states can be used to develop a taxonomy of species “recovery” that acknowledges there are multiple stable points defined by ecological and social factors. “With this approach, we hope to contribute to a new, optimistic conservation biology that is not based on underambitious goals and that seeks to create the conditions under which Earths biological systems can thrive.

How Many Animals Do We Want to Save? The Many Ways of Setting Population Target Levels for Conservation

ABSTRACT Conservation biologists struggle to decide how many animals to save. In this article, I outline 18 approaches to setting population target levels (PTLs) for animals, with rules of thumb and analytical recommendations for each approach. Minimally viable populations, the most common target level, are necessary but not sufficient for most efforts, given the range of values that bear on conservation. Reference ecosystems, either extant or historical, are key for setting practical target levels. Setting PTLs sufficient for conserved populations to be animals in all respects (including functional, social, landscape, ethical, aesthetic, and spiritual aspects) is a critical consensus point. In many cases densities as well as overall population size will need to be specified. I suggest a four-tiered system of setting incrementally higher population target levels such that conservation provides first for demographic sustainability, then ecological integrity, then sustainable use, and finally restoration of historical numbers of wildlife, based on times when human beings had less impact on the planet than we do today.

Range-wide declines of a key Neotropical ecosystem architect, the Near Threatened white-lipped peccary Tayassu pecari

We report a range-wide status assessment of a key Neotropical ecosystem architect, the white-lipped peccary Tayassu pecari , categorized as Near Threatened on the IUCN Red List, using published information and unpublished data from 41 scientists in 15 range countries. We estimate that the white-lipped peccary has been extirpated in 21% of its historical range over the last 100 years, with reduced abundance and a low to medium probability of long-term survival in another 48% of its current range. We found major range declines in Argentina, Paraguay, southern Brazil, Colombia, Venezuela, north-east Brazil, Mexico and Costa Rica. This species is particularly at risk in more xeric ecosystems, especially the caatinga, cerrado and pampas. Hunting and habitat destruction are the most severe threats, although there are also unexplained sudden die-offs suggestive of disease. We evaluate our results in light of this species’ important interspecific interactions and its role as an ecosystem architect. One of our recommendations is that conservation efforts should focus on landscape conservation of large, continuous and ecologically intact areas containing a mosaic of different habitat types.

What is the role for conservation organizations in poverty alleviation in the world's wild places?

In this paper we provide an empirically-based way to address the general question of the broad-scale spatial relationship between poverty occurrence and areas of interest to those seeking conservation of large wild areas. We address the question of the spatial relationship between poor people and areas less impacted by human activity by asking three questions about the global spatial relationship between poor people and ecological intactness and how it varies by major biome and geographical region. We use infant mortality rate as a proxy for poverty and the Human Footprint as a proxy for ecological intactness, comparing global terrestrial maps of both. The analysis shows that the vast majority of the worlds poor people live in extremely urban and very transformed (peri-transformed) areas. Only a small percentage of the worlds most poor are found in areas that are somewhat or extremely wild: about 0.25% of the worlds population. This fact has implications for the calls being made for conservation organizations to under- take poverty alleviation, suggesting that at a global scale those groups with interest in conserving wild areas would be able to contribute little to globally significant poverty alleviation efforts. However, these conservation groups are well positioned to develop new partnerships for delivery of benefits to some of the least accessible poor people in the wildest places of the world.

The Landscape Species Approach: spatially-explicit conservation planning applied in the Adirondacks, USA, and San Guillermo-Laguna Brava, Argentina, landscapes.

The Landscape Species Approach is a framework developed by the Wildlife Conservation Society for planning landscape-scale conservation based on a suite of focal species. The approach has so far been implemented at 12 terrestrial and two marine sites. We demonstrate the approach using two sites, the Adirondack Park, USA, and San Guillermo-Laguna Brava Landscape, Argentina. We describe the spatially explicit components, including steps to map the attainable (Biological Landscape), current, and future distribution of Landscape Species, human activities (Human Landscapes) and their impacts on Landscape Species, the possible impacts of conservation actions (Conservation Landscapes), and a procedure to set spatial conservation priorities. We discuss advantages and innovations of the approach, including how it incorporates both vulnerability of biodiversity and possible recovery. Finally, we discuss improvements that can be made to the approach, costs, and implications for conservation at the two sites.

Global terrestrial Human Footprint maps for 1993 and 2009.

Remotely-sensed and bottom-up survey information were compiled on eight variables measuring the direct and indirect human pressures on the environment globally in 1993 and 2009. This represents not only the most current information of its type, but also the first temporally-consistent set of Human Footprint maps. Data on human pressures were acquired or developed for: 1) built environments, 2) population density, 3) electric infrastructure, 4) crop lands, 5) pasture lands, 6) roads, 7) railways, and 8) navigable waterways. Pressures were then overlaid to create the standardized Human Footprint maps for all non-Antarctic land areas. A validation analysis using scored pressures from 3114×1 km2 random sample plots revealed strong agreement with the Human Footprint maps. We anticipate that the Human Footprint maps will find a range of uses as proxies for human disturbance of natural systems. The updated maps should provide an increased understanding of the human pressures that drive macro-ecological patterns, as well as for tracking environmental change and informing conservation science and application.

Mannahatta: An Ecological First Look at the Manhattan Landscape Prior to Henry Hudson

Abstract The British Headquarters Map, circa 1782, provides a remarkable window onto the natural topography, hydrology, and land cover of Manhattan Island, NY, before extensive urbanization. Manhattan formerly hosted a rugged topography watered by over 108 km of streams and at least 21 ponds, flowing in and out of wetlands that covered nearly 10% of the island in the late 18th century. These features are largely representative of the landscape prior to European settlement. We used ecological features interpreted from the British Headquarters Map, and additional historical, ecological, and archeological information, to hypothesize about the ecosystem composition of the pre-European island. We suggest that 54 different ecological communities may have once been found on the island or in nearby waters, including chestnut-tulip tree forests, Hempstead Plains grasslands, freshwater and tidal marshes, hardwood swamps, peatlands, rocky headwater streams, coastal-plain ponds, eelgrass meadows, and culturally derived ecosystems, such as Native American village sites and fields. This former ecosystem mosaic, consisting of over 99% natural areas, stands in sharp contrast to the 21st-century state of the island in which only 3% of its area is dedicated to ecological management.