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Habitat destruction and fragmentation poses one of the most serious threats to biodiversity in conservation biology. What distinguishes habitat fragments is that the intervening gaps are often vegetated, rather than open expanses of ocean. This intervening habitat, referred to as ‘the matrix’, differs in species composition or age and/or structure of the vegetation so as to be sufficiently distinct from the remnant habitat islands they surround. Matrix habitat is considered less hospitable for remnant-dwelling species, yet terrestrial matrices may not be quite as impermeable as open oceans. This chapter addresses the potential for breeding in altered habitats, such as those found in managed habitat matrices that separate remnant, native forest. Using studies on both Eurasian tits and North American chickadees, analyses investigating breeding in forests of divergent habitat quality are paralleled with proposed management of matrix vegetation as alternative breeding habitat for matrix-tolerating species.

This chapter models biodiversity alongside ecosystem services to identify potential win–win protected areas that capture both biodiversity and other ecosystem services, and also models biodiversity to uncover trade-offs which arise when imposing different land-management schemes. Specifically, it describes three models that estimate the status of biodiversity across a landscape, under current or future conditions. In the first, the chapter presents an algorithm for measuring habitat quality across the landscape. This tier 1 approach is designed as the first phase of a conservation assessment, in the absence of location data for biodiversity targets. The second and third models are at the tier 2 level, and require detailed species data on geographic range and habitat compatibility. The former calculates the relative contribution of a parcel’s habitat to the overall quantity of suitable habitat across a landscape. The latter model aggregates information on species distributions and habitat suitability into a single landscape score of biodiversity status. The chapter illustrates the workings of the models with data and scenarios from the Sierra Nevada Conservancy in California.

This chapter reviews the impact of habitat on the distribution and abundance of unionoids. The discussion covers the habitat requirements of unionids, the frequency of habitat limitation in nature, and density-dependent feedbacks onto habitat quality.

A replicated reintroduction experiment of water voles Arvicola terrestris in the Upper Thames was undertaken to reverse the species’ decline, and to learn lessons for future reintroductions. Cohorts of forty-four water voles were released into twelve replicate 800 m stretches of river, each supporting a different habitat abundance. Five populations failed to establish or were later lost. Seven populations established and spread. At sites with higher vegetation abundance more of the release cohort survived, and post-establishment survival rates and population densities were higher. Prior to release, measures of immunocompetence were negatively correlated with group size, suggesting that individuals housed in larger groups were more physiologically stressed. These experimental reintroductions reversed the decline of water voles in the Upper Thames, and demonstrated that the release habitat should be the best available and that housing conditions pre-release must be optimized for the species in question.

This chapter examines the role of time as a determinant of animal survival or reproduction in a given habitat, mainly by limiting an animal's foraging ability. More specifically, it analyses the time constraints under which animals labour, and how these are affected by climate and habitat quality. The chapter proposes a linear programming approach to time budgets that attempts to explain both a species' ability to survive in a particular habitat and the constraints on its social and demographic arrangements, including group size, by taking into consideration a number of additional dimensions such as life history and predation risk. Because these models are climate-driven, they can also be used to elucidate both the selection pressures that have acted on a particular taxonomic lineage during its evolutionary history and its capacity to cope with future climate change.

The transmission of vector-borne diseases is sensitive to environmental conditions, including temperature, humidity, rainfall, and land use/habitat quality. Understanding these causal relationships is especially important as increasing anthropogenic changes drive shifts in vector-borne disease dynamics. In this chapter, we first briefly describe the biology of vectors and pathogens that underlies environmental influences on transmission of vector-borne diseases. Next, we review the impacts of each of the major environmental drivers (as previously mentioned), synthesizing and comparing mechanisms across different vector-borne disease systems. Then, we discuss key challenges and standard approaches to research in the discipline. Finally, we highlight areas where research is advancing in promising new directions and suggest areas where new approaches are needed.

This chapter discusses the extensive spatio-temporal environmental variation that parents and offspring are likely to experience during dispersal, making its costs and benefits more likely to be distinct across generations. The process of dispersal is costly, and it is often more advantageous for individuals to remain in their natal population. Variation in habitat quality, however, can sometimes more than compensate for the cost of dispersal — especially in cases where individuals escape a habitat of declining quality. This chapter explores the conditions that might favour both constancy and context-dependency in dispersal phenotypes across generations for species that experience spatio-temporally varying habitat. The focus here is on spatio-temporally varying environments, since theoretical models suggest that environmental variation is the most common evolutionary cause of dispersal and because spatial and temporal environmental variation is ubiquitous in natural systems.

This chapter focuses on the documented effects that recent changes in habitat quality, climate, and biotic interactions have had on the spatiotemporal regimes of migrating animals. Animals of a large number of taxa and ecological traits have been affected. Most habitat changes have been detrimental, such as the loss of tidal mud flats sites for migratory fuelling, and roads, fences, and dams that cut off migration routes. At the same time, relatively new habitats such as urban areas and intense agriculture have had positive effects. Climate change has had the largest impact on the timing of movement, but few examples exist of its influence on migration’s spatial aspect. Biotic interactions, such as increased hunting and higher numbers of falcons, have affected animal migration in both time and space. In general, the threat from rapid global change appears largest for terrestrial animals, long-distance migrants, habitat specialists, and animals with slow reproduction.