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William F. Laurance provides an overview of contemporary habitat loss in this chapter. Vast amounts of habitat destruction have already occurred. for instance, about half of all global forest cover has been lost, and forests have virtually vanished in over 50 nations worldwide. Habitat destruction has been highly uneven among different ecosystems. From a geographic perspective, islands, coastal areas, wetlands, regions with large or growing human populations, and emerging agricultural frontiers are all sustaining rapid habitat loss. From a biome perspective, habitat loss has been very high in Mediterranean forests, temperate forest‐steppe and woodland, temperate broadleaf forests, and tropical coniferous forests. Other ecosystems, particularly tropical rainforests, are now disappearing rapidly. Habitat destruction in the temperate zone peaked in the 19^th and early 20^th centuries. Although considerable habitat loss is occurring in some temperate ecosystems, overall forest cover is now increasing from forest regeneration and plantation establishment in some temperate regions. Primary (old‐growth) habitats are rapidly diminishing across much of the earth. In their place, a variety of semi‐natural or intensively managed ecosystems are being established. For example, although just two‐tenths of the temperate coniferous forests have disappeared, vast areas are being converted from old‐growth to timber‐production forests, with a greatly simplified stand structure and species composition. Boreal ecosystems have suffered relatively limited reductions to date but are especially vulnerable to global warming. Boreal forests could become increasingly vulnerable to destructive fires if future conditions become warmer or drier.

Ecological communities consist of species that interact to varying degrees within the same geographical area, and so by definition exist within a landscape context. This chapter begins by reviewing the measures and different scales at which species diversity can be assayed, including the use of spatial partitioning to evaluate multiscale patterns of diversity. The chapter then reviews correlates of species diversity, including explanations for latitudinal and elevational diversity gradients, before considering how habitat loss and fragmentation are expected to influence species diversity. The chapter tackles the debate surrounding the relative importance of habitat amount versus fragmentation in predicting species’ responses to landscape change, and highlights the importance of studying these effects at a landscape rather than patch scale. The chapter concludes with a discussion of landscape effects on different types of species interactions, and how interactions among species in different communities can give rise to metacommunity structure and dynamics.

The chapter describes the geology, oceanography, and patterns of biogeography of the California kelp forests. The structure and biodiversity of the kelp forest food web for all trophic guilds is described as well as findings from experimental manipulations and long time series studies. The chapter finishes with a discussion of the role of fishing, habitat loss, and climate change on these kelp forests.

Few Holocene marine species extinctions have been recorded, and these have been of range-restricted species, mainly mammals and birds, over the past 300 years. However, marine extinctions may be more widespread than is currently appreciated, because it is difficult to observe the last individuals of a marine species, and because of a fallacious but widespread perception that marine organisms cannot be driven to extinction. Today's extensive overexploitation of global fisheries has a historical and prehistoric precedent in archaeological evidence for the local collapse of many fisheries and shellfish beds, and regional extinction of marine populations. The observed human capacity for causing rapid and widespread terrestrial extinctions combined with the rapidly increasing scale of human impact on the sea forewarn of an impending marine extinction event. The scale of this may be the equivalent of concatenating both of the terrestrial late Quaternary extinction waves into a much shorter timeframe.

The distribution and dynamics of populations reflect the interplay between dispersal and demography with landscape structure. Understanding how landscape structure affects populations is essential to effective habitat management and species conservation, especially within landscapes undergoing habitat loss and fragmentation as a result of human land-use activities. This chapter thus begins with an overview of the effects of habitat loss and fragmentation on populations, followed by a discussion of species distribution modeling. Then, because population assessment figures so prominently in evaluating a species’ extinction risk to landscape change, the chapter considers the different classes of population models used to estimate population growth rates and population viability, including the use of metapopulation and spatially explicit simulation models.

Historically, farmers obtained pollination services from wild, unmanaged bees or made habitat modifications to attract them. Today, agriculture demands the use of managed bees, usually honey bees, although their availability is becoming uncertain due to diseases, pests, and other unknown causes of mortality. This chapter addresses the roles that wild bees play in agriculture today, and what roles they could play in the future. Research has shown that in some circumstances, wild bees can partially or fully replace managed bees or actually enhance their effectiveness as pollinators. Land use changes and habitat loss impact wild bee communities and their ability to provide pollination services within agricultural systems, and agricultural intensification can affect wild bee diversity and abundance in both positive and negative ways. The economic value of wild bee services is discussed, and the ways in which agricultural lands can be managed to restore healthy communities of wild bees.

Humans have used and had an impact on marine ecosystems throughout history. As human populations and their economic activity increased the impact intensified, but our awareness of the long‐term, pervasive effects on marine life is relatively recent and very incomplete. This chapter introduces some of the ethical and utilitarian values which underlie our relationship with marine ecosystems and gives a brief overview of historic evidence concerning past states of marine ecosystems and intensification of human impacts. It describes impacts of fishing and other human pressures on the demography and biomass of exploited species and on loss of vulnerable species and habitats. Fishing and climate interact to cause observed change to ecosystems, including their trophic structure, with consequences for resilience and productivity. Emerging conclusions about human impacts, future human stewardship and utilization of marine ecosystems are presented.

Freshwater ecosystems worldwide are highly threatened. As a consequence, many dragonfly species are also threatened. The threats to them are many and varied, including invasive alien plants and habitat loss. Global climate change is also beginning to affect them, with some species changing their geographical ranges. Worldwide assessments are being made of dragonfly conservation status. They are one of the highest profile invertebrates in conservation awareness, planning, and action. One reason for this is that they are highly valued, being iconic, aesthetic, and sensitive bioindicators of landscape change. They are both important subjects in their own right as well as important role players in overall biodiversity conservation.

This chapter discusses the conservation and management of migratory animals and the phenomenon of migration. It begins with an overview of the diversity of migratory organisms; migration loss and its potential ecological and economic impacts; and strategies for managing migratory species and migratory behaviour. Subsequent sections detail the major threats facing migratory species (habitat loss/degradation, over-exploitation, climate change, interrupted migration); how different environments and specific migratory characteristics (site fidelity, aggregation, behavioural plasticity) can influence a migrant's vulnerability to these threats; existing conservation, restoration and management approaches; and the institutional frameworks that support conservation and management. Case studies profile terrestrial, aerial, and aquatic migrants, and describe their biology, threats, and conservation management. The chapter closes with an assessment of the difficulties associated with developing effective conservation strategies for migratory species and an overview of some of the multilateral agreements that are often critical for their protection and management.

The guppy raises three different classes of conservation issues. First, the species is a useful model for freshwater fish species — one of the most endangered vertebrate groups. Second, although guppy populations are generally large and the species is widely distributed across Trinidad, some of the diversity that has provided such rich material for evolutionary biology is under threat from pollution, habitat loss, exotic introductions, and so on. Guppy populations are also potentially at risk from scientists who observe, collect, and manipulate guppy populations. Artificial introductions have proved very informative but may lead to irreversible changes in a river. Finally, introductions of guppies to countries outside their range, either for the control of malaria vectors, or through escapes of ornamental fish, can adversely affect vulnerable faunas. This chapter discusses these issues.

This chapter summarizes the many reasons the conservation of orchids in Australia will not be easy. Among the problems confronting those who would protect Australia’s glorious orchids are habitat loss, damage from livestock, invasive weeds, dieback from fungal disease, and the salinization of the land. Although the list of problems is large and daunting, there have been some success stories, and these are recounted.

This chapter discusses habitat loss and fragmentation on the Åland Islands in the Baltic Sea. It first provides a background on the Glanville fritillary research project and how it has evolved into a model system for metapopulation biology before discussing the impact of infectious diseases on the dynamics of butterflies and other animals and plants in fragmented landscapes such as Åland. In particular, he considers the concept and theory of the extinction threshold at the landscape level by drawing on evidence from the Glanville fritillary study. The chapter also comments on the debates about habitat fragmentation and its consequences for biodiversity, including that of forest-inhabiting species, and concludes with an analysis of the so-called third-of-third rule in habitat conservation.

This chapter focuses on the connection between citizen science and landscape ecology and how it can widen the circle of scientific research across space and time. It first explains how citizen science can be used to test many pertinent hypotheses regarding the cause and biological consequences of habitat loss and fragmentation. It then looks at past uses of citizen science to investigate the effects of habitat loss and fragmentation and goes on to discuss how citizen science can be employed to answer questions in landscape ecology, such as combining citizen science data with environmental data of an appropriate spatial extent and resolution.

This introduction briefly introduces all the chapters. This book provides cutting‐edge but basic conservation science for the inhabitants of both developing as well as developed countries. Authoritative chapters are written on balancing conversion and human needs, climate change, conservation planning, designing and analyzing conservation research, ecosystem services, endangered species management, extinctions, fire, habitat loss, and invasive species are covered. Numerous textboxes describing additional relevant material or case studies are also included. The book is written for undergraduate and graduate students as well as scientists, managers, and personnel in governmental and non‐governmental organizations. The book has all the necessary topics to become a required reading for various undergraduate and graduate conservation‐related courses. English is kept at a level comprehensible to people with English as a second language. Overall, this book represents a project that the conservation community has deemed worthy of support by donations of time and effort. None of the authors will gain financially from this project.

Phylogeographic studies can be very useful in defining evolutionary significant units for conservation purposes. When concordance among divergent major clades is identified, phylogeographic studies are useful in providing the basis needed for major conservation efforts in particular regions. Many regions of high diversity are in need of further support in terms of conservation efforts that will strengthen legal protection, provide and strengthen migratory corridors, and increase the size of parks and preserves to protect biological diversity. Anthropomorphic changes to the evolutionary process that can result in a loss of biological diversity include a loss of habitat or range reduction, habitat fragmentation, hybridization of nonlocal genotypes, reduction of genetic variation, disturbance, invasive species competition, changing fire regimes, and climate changes.

In this chapter, habitat change is broken down into three components: habitat loss, habitat fragmentation, and habitat degradation. For each, the nature and extent of the pressure is described, exactly how it threatens primates, and what is known about how primates respond. Theoretical frameworks (e.g. species–area relationships, metapopulation dynamics) that can be useful in modelling primate declines are covered; only when empirical data are used to build and test such frameworks can primate conservation biologists make specific, useful conservation recommendations. In the real world, all three components of habitat change often act synergistically, leaving us with reduced, fragmented, and degraded primate habitat—often it is hard to ascribe primates’ reactions to a particular force. More work is urgently needed, both to understand how habitat change contributes to primate declines (so that conservation practitioners can guide land-use practices and conservation interventions), and to reduce the rate of habitat change itself.

This chapter shows that direct habitat loss is recognized as the main cause of species extinction, and how habitat fragmentation is an inherent consequence of habitat loss. This causal relationship has made the analysis of the relative impact of habitat loss and fragmentation on biodiversity more complex, since their effects are quite hard to distinguish. Model-based approaches underscore the necessity of considering the effect of both habitat loss and fragmentation on genetic variation and dynamics of metapopulations, and further experimental designs under controlled conditions should help validate such predictions. The review material that addressed the consequences of habitat fragmentation on biodiversity repeatedly identified the decrease of connectivity among habitat remnants associated with habitat fragmentation as a major driver of extinction.

American marten are associated with extensive and unfragmented late seral forest habitats, and are often considered to be particularly vulnerable to habitat loss and fragmentation. This chapter evaluates the impact of road building and timber harvest on habitat suitability for marten in northern Idaho, USA, using an empirically derived, multi-scale habitat suitability model, reconstructing key predictor variables (elevation, forest type, road density, canopy cover, landscape fragmentation and the extensiveness of late seral forest in the landscape) as they appear to have existed prior to harvest, and applying the model to both current and pre-harvest conditions. Calculating changes in the extent and pattern of habitat in the landscape indicate that timber harvest and road construction together reduced marten habitat quality considerably across the study area, which is likely responsible for current patterns of reduced detection rates and lower genetic diversity in areas that have experienced the largest amounts of habitat loss.

The ability to understand the ecology of herbs of forests of eastern North America is hampered by declining abundances and increasing risks of extinctions, particularly for rare taxa. Major causes for global decline in biodiversity include habitat loss, the presence of alien species, overexploitation, and secondary (or indirect) effects resulting from impacts of other taxa. The consequences of the many ramifications associated with global change also have the potential to become another major cause of the decline in biodiversity. This chapter uses the framework of threats and global change to review major challenges to the diversity of herbs associated with forests of eastern North America, especially taxa listed as endangered or threatened. It considers what progress has been made in the understanding of the ecology of the herbaceous flora of eastern North American forests.

This chapter evaluates biases that contribute to the common misrepresentation of fragmentation as a major threat to biodiversity. The idea that habitat fragmentation seriously threatens biodiversity is so widespread that it might be considered a “conservation biology principle.” However, effects attributed to habitat fragmentation are usually confounded with effects of habitat loss. A recent review of the effects of habitat fragmentation per se (effects independent of habitat loss) indicated that 76% of significant effects of fragmentation were positive, and in no situation were most effects negative. Comparing the abstracts of papers with the actual results reported in the body of each paper revealed that fewer than half of the authors who found only positive fragmentation effects actually discuss these positive effects in their abstracts. Thus, authors themselves reinforce the misrepresentation of the fragmentation literature, potentially because authors fear that their results could be incorrectly used to justify habitat destruction.