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Aram J.K. Calhoun, Assistant Research Professor of Wetland Ecology, Department of Applied Ecology and Environmental Sciences, University of Main
Increasingly fragmented landscapes, dynamic population patterns, and limited natural resources are trends that demand a proactive, knowledge-based approach to land management. Linking the best available scientific information with resource policy will shift crisis-based management to proactive conservation strategies. In Maine, we have been successful at combining limited financial and human resources to address conservation issues through a partnership among our research scientists, non-governmental organizations, and state resource managers. This unusual partnership continues to enhance herptile conservation efforts in the state, including joint research initiatives, volunteer programs for vernal pool mapping and monitoring, development of best management practices for forestry and vernal pools, conservation education initiatives, and inventory and atlasing projects.

James H. Cane, Research Entomologist, USDA-ARS Bee Biology and Systematics Lab, Utah State University
Most native bees are solitary, not social, but all commute from a single fixed nest site to scattered flower patches where females gather pollen and nectar needed by their grub-like progeny. Most nest underground, requiring specific soil textures, moistures and aspects; dense turf, pavement, and mechanically compacted soils are usually unsuitable. Other species nest in insect-riddled deadwood or tunnels bored into pithy stems. Some bees require specific flowering species; such bees (and plants) may fail to reproduce if widely dissociated. In Tucson, Arizona, 70 years of desert habitat fragmentation have impacted but not decimated native bee faunas. Ground-nesting floral specialists have declined sharply in the smallest host fragments. In older residential neighborhoods, some cavity-nesting species flourish, where they have the right floral hosts and suitable nesting substrates within flight range of each other. Work elsewhere with a native, ground-nesting alfalfa pollinator shows that, if potential nest sites become too widely separated, natural recolonization halts and the bee's pollination service is lost. Pollinator restoration, following local extinction, is at best a gamble, but generally infeasible. Modest concessions to bees' nesting and floral needs should allow diverse species to persist in our human-impacted landscapes.

Peter Daszak, Assistant Research Scientist, Department of Botany, University of Georgia
Human population changes have played a central role in the emergence of disease. This began with the development of the first large cities and outbreaks of smallpox, tuberculosis and measles (the Old Testament plagues). More recent urbanization has occurred hand-in-hand with the rise of hemorrhagic dengue, malaria and yellow fever. As our cities expand, we encroach into wildlife habitats and increase our contact with new pathogens and vectors. Hantavirus pulmonary syndrome, Lassa fever, cryptosporidiosis, Nipah virus disease and plague have all emerged due to urban expansion and associated development. Emerging diseases also threaten wildlife populations. Just as domestic animals can pass on wildlife pathogens to us (e.g. rabies, Nipah virus), expansion at the edge of human settlements brings livestock pathogens in contact with wildlife. This leads to loss of biodiversity, but also, when introduced diseases persist, threatens human health. Thus, the threat of disease emergence due to urban sprawl encompasses a number of subtle, complex, and often overlooked threats.

Jane Elder, Executive Director, The Biodiversity Project
In a democracy, public engagement is critical for effective social change. Our messages-about urban sprawl, about biodiversity loss-must compete for public attention with the background noise of modern media and increasingly busy, complex lives. To be heard, our communications strategies need to be clear and incisive. For too long, we have assumed that more information will compel the public to act, but information is only part of the equation. Our messages must also speak to values, and the underlying motivations that make people care-an essential step in getting people to act.

On sprawl, we need to look at the complex mix of values that Americans associate with this issue. We're up against old perceptions of the American Dream, fears about safety and security in our neighborhoods, and a whole host of things that have contributed to the sprawl phenomenon in the first place. To counter this, we'll need to appeal to visions of the world we will leave to our children, our desire for beauty and nature in our lives. We need to be clear about the choices and solutions, and find compelling ways to make the environmentally sound choices more appealing than the status quo.

Niles Eldredge, Curator, Division of Paleontology, American Museum of Natural History
"Biodiversity" (a contraction of "biological diversity") means all the species living in all the world's ecosystems. There are at least 10,000,000 species on earth right now - but some 30,000 a year (3 per hour!) are currently becoming extinct through human activity, including conversion of forests and prairies for agricultural use, overfishing and timbering, and the introduction of alien species around the globe. The baseline cause of this "Sixth Extinction" is the growth of human population from ca. 6 million only 10,000 years ago, to a full 6 billion at the year 2000 - a byproduct of the first Agricultural Revolution. The invention of agriculture caused humans to become the first species in the 2.5 billion year history of life to live outside of local ecosystems - and as a result it is difficult to see what the significance of the loss of biodiversity has for the planet as a whole - and especially for human life. Yet humans rely on some 40,000 species of animals and plants every day for food, shelter, clothing, and medicines; we continue to rely on the cycling of essential nutrients, the production of oxygen, and the availability of safe water for drinking - and all of these depend on the continued existence of healthy ecosystems (perhaps as many as 2 of the 6 billion people on earth do not currently have access to safe drinking water). Combined with esthetic and ethical considerations, these are powerful reasons for asking the question: What can we do to stem the tide of the mounting Sixth Extinction?

Stephen Farber, Director of the Environmental Management and Policy Program and Director of the Environmental Decision Support Program, University of Pittsburgh
The variety and spatial distribution of urban ecosystems play an important role in urban economies. These ecosystems provide low-cost services and benefits that make urban areas more attractive, enhancing tax bases, and reduce the need for more costly man-made infrastructure, such as storm water management and treatment systems. Proper land use in the face of urbanizing pressure can not only enhance the health of ecosystems, but also provide measurable economic benefits. This presentation discusses the relations between urban ecosystems and economies, and suggests methods of measuring the benefits of ecosystem management to sustaining urban economies. Illustrations will be drawn from a watershed management case study in the Pittsburgh region.

William Honachefsky, Environmental Planner, New Jersey Department of Environmental Protection
Clearly, the nation is poised on the threshold of a land planning renaissance that could significantly alter the way in which Americans in general and local governments in particular conduct the business of land use planning. This reformation should include a much greater emphasis on environmental and ecological protection, thanks to the public's indignation over the landscape evolving from the present system of land use and the concerted effort by state and federal environmental regulators to recruit and incorporate local governments into their environmental protection agendas. The motto of this reformation is simply this: "The quality of our lives is dependent upon the quality of our environment, which is dependent upon the quality of our land use." Despite all the compelling evidence and cogent arguments, both recent and historic, favoring the implementation of a more ecologically sensitive approach to land use planning, municipal planners remain frustratingly wary. It is apparent that it will take considerably more encouragement and education to win over their hearts and minds completely. This presentation is a commencement of that effort.

Michael W. Klemens, Director, Metropolitan Conservation Alliance, Wildlife Conservation Society
The development pattern that we refer to as sprawl creates a legacy of homogenized, dysfunctional ecosystems; reducing biodiversity, increasing biomass of a comparatively small number of adaptable species, and diminishing vital ecosystem services upon which all life depends. Habitat fragmentation is the primary threat to biological diversity in the United States, and increasingly around the world. In our country, especially in the biologically rich regions that surround many metropolitan areas, poorly planned growth is the major contributing factor to habitat fragmentation. Sprawl has its roots in the years immediately following World War II, fueled by increasing prosperity, cheap energy, and the creation of the interstate highway system. The results of landscape fragmentation include a reduction of biological diversity, along with increases in populations of highly adaptable species, such as white-tailed deer and Canada geese. Non-native species, such as purple loosestrife, thrive in fragmented habitats. Subsidized predators - animals such as skunks, raccoons, and crows that prey on other animals and flourish in human-altered landscapes - disrupt the ecological balance in fragmented habitats. Apart from these species-level impacts, sprawl threatens the ecosystem processes that maintain biodiversity. These processes, such as flooding cycles or fire, are altered in fragmented habitats, leading to the incremental homogenization of ecosystems. Fragmented habitats are vulnerable to catastrophes, affecting not only wildlife, but human social and economic well-being.

Barbara Lawrence, Executive Director, New Jersey Future
For most Americans at the beginning of the new century, sprawl is the dominant landscape. Single-use zones of low-density residential development with scattered commercial and industrial destinations define our daily living. In many places, towns and cities - even first-generation suburbs - are facing disinvestment at a time of unprecedented prosperity. How we got to this point is a complicated web of intentional decisions coupled with unintended consequences, and a measure of the American spirit. The seeds for this land-use pattern were planted in the early 20th century with the notion that certain noxious industrial activities should be separated from the places where people live. This quality of life improvement became the bedrock for millions of local zoning decisions that add up to the patterns we see today. State and federal government regulatory and spending actions play equally important roles in the location and character of new development. In addition, technology - especially but not only the automobile - has made vast separations of land-use possible.

Stuart Meck, Principal Investigator for Growing Smart, American Planning Association
A sea change is under way in the United States. It has to do with how we shape the character of our communities by shaping their patterns of development. This presentation will review the historical backdrop of planning statute reform in the United States, from basic systems developed in the 1920s to eliminate or minimize nuisances or land-use conflicts, to modern systems designed to phase or sequence growth, encourage compact development, remove barriers to affordable housing, and protect natural resources. It will highlight the American Planning Association's Growing Smart project, a multi-year effort to draft the next generation of model planning and zoning legislation for the United States, which has been incorporated into bills and legislation in 11 states. The presentation will particularly focus on Growing Smart proposals to integrate environmental considerations into the planning process. Finally, the presentation will evaluate some recent efforts by states to enact anti-sprawl legislation, including Maryland, Tennessee, Utah, and Wisconsin. It will conclude with a critical assessment of what it takes to change development practices to reduce land consumption in the face of population and employment growth or shifts.

William A. Patterson, III, Professor, Forestry and Wildlife Management, University of Massachusetts
Northeastern pine barrens have traditionally been considered wastelands. Although frequently subject to wildfires and unproductive as timber land, barrens provide habitat for a variety of rare plant, animal, insect, and bird species. Long sought after by developers of airports, industrial parks and residential housing, barrens protect important aquifers and provide open space in a region where outdoor recreational opportunities are often limited. Here I review the ecological and social values of barrens, and describe how fragmentation by urban sprawl and efforts to eliminate wildfires are altering the natural functioning of an ecosystem type that has, simultaneously, been the object of intense conservation efforts. I propose answers to the question: How can resource managers preserve fire-dependent plant and animal communities in a region where fragmentation of the landscape and encroachment by development places constraints on the application of the preferred treatment-prescribed management fires?

Justina C. Ray, Professor, Faculty of Forestry, University of Toronto
Fragmentation of habitats by agriculture, intensive forest use, and urban sprawl is widely recognized as a serious threat to the conservation of biodiversity. The most obvious impacts are loss of habitat or break-up of critical habitat into small isolated patches. Both have negative implications for wide-ranging species such as carnivores, raptors, and migratory birds, creating pervasive edge effects, barriers to movement through the landscape, and splitting populations into smaller, extinction-prone sub-populations. Human-dominated landscapes also provide habitats for mid-sized predators (e.g., raccoons, skunks, corvids, and even housecats), which have been implicated in the decline or disappearance of small vertebrate prey in a variety of ecosystems. In addition to increased predation rates close to edges, nests of migratory song birds often fall victim to parasitism by cowbirds-a species that, along with the coyote, has been a successful colonizer of the Northeast following forest clearance for agriculture. Forest fragmentation has resulted in shifts in carnivore and raptor community composition, so that, over relatively short periods, species have been forced to share their ranges with a revised suite of potential competitors. Those species with more specialized resource requirements, such as marten, lynx, redshouldered hawks, and barred owls, are most vulnerable.

M. A. Sanjayan, Director of Conservation Science, The Nature Conservancy of California
Habitat fragmentation is now thought to be one of the leading proximate causes of population extirpation and species extinction. As nature is carved into pieces, remnant habitat is often insufficient (in size, configuration, and location) to provide viable habitat for many different species, including top carnivores, migratory birds, fish, and native pollinators. In addition, fragmentation also impairs ecosystem integrity by, for example, upsetting the balance of prey species through the exclusion of predators, or preventing riparian forest regeneration by limiting floodplains. Connectivity must be maintained or restored if landscapes are to maintain viable populations of species and remain ecologically functional. In areas such as Southern California and Florida, where high population densities are the norm, restoring connectivity is often the only option left for maintaining the viability of many protected areas. However, connectivity for connectivity's sake is rarely useful, and indeed some kinds of "corridors" can actually hamper conservation efforts. By focusing on underlying ecological processes (migration, river hydrodynamics, home range movement, etc.) when restoring missing linkages, land-use planners and conservation biologists can better knit together a network of functional landscape for the benefit of nature.

Wayne C. Zipperer, U.S.Department of Agriculture Forest Service
Forest fragmentation from urban sprawl is a site-level phenomenon; however, it affects conservation of biodiversity at landscape and regional scales. Impediments to conservation occur when crossing jurisdictional and agency (local, state, and federal) boundaries. The Chesapeake Bay and Highlands Programs, USDA Forest Service projects, address both types of impediments. Each project has dedicated personnel to facilitate communication and partnerships within and among agencies, to assess fragmentation at landscape and regional scales, and to develop management options for biodiversity conservation. Another USDA program, Urban Resource Partnership (URP), specifically coordinates federal agencies to help create livable cities, thus reducing emigration into surrounding rural landscapes.

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