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Habitat fragmentation occurs when a large, fairly continuous tract of vegetation is converted to other vegetation types such that only scattered fragments of the original type remain. Problems associated with habitat fragmentation include overall habitat loss, increase in edge habitat and edge effects (particularly higher parasitism and nest predation rates), and isolation effects. Birds show variable responses to fragmentation, with the most conservation concern focused on so-called "area sensitive" species that remain only on large habitat fragments. Management responses to fragmentation...

Description of the system: Bottomland hardwood forests (including bald cypress and tupelo swamp forests) are historically the dominant natural community of riverine floodplains of the southeastern United States. Their greatest single expanse was in the 21 million acre floodplain of the lower Mississippi River Valley from southern Illinois to coastal marshes along the Gulf of Mexico, but the community also occurs along rivers of the piedmont and southern coastal plain from Virginia to east Texas (Patrick et al. 1981). The biotic and physical features of this system are determined by...

Habitat management for neotropical migratory birds must be based upon land capability, vegetation, successional patterns, response to treatments, landscape diversity, and speciedhabitat relationships. Neotropical migratory birds use diverse arrays of aquatic, early successional, and forest habitats. Management of neotropical migratory birds involves enhancement of habitat diversity. We describe a process that includes evaluation of potential habitat capability, inventory of existing conditions, and prescriptions for necessary structural features for species diversity. Silvicultural...

Most greenways are created with multiple goals in mind. Two of the foremost are providing recreational opportunities and conserving nature. Although these two goals frequently enhance each other, sometimes pursuing both simultaneously can result in conflicts. In some cases, recreational use can so severely degrade an area that not only is the environment damaged but the quality of the recreational experience itself is diminished. This chapter explores various ways of reducing the conflict between recreational use and nature conservation. The chapter begins with an overview of the impacts...

We develop and explain a species ranking system for the states and physiographic regions of the Neotropical Migratory Bird Conservation Program's West Working Group. The ranking criteria attempt to measure characteristics of species which make them vulnerable to extirpation, as well as assess the relative importance of different geographic and/or political areas to the species in question. These criteria include: the importance of the area of consideration to the species as a whole (importance of area), global abundance, threats on the breeding grounds, threats on the wintering grounds,...

Riparian ecosystems are among the rarest and most sensitive habitat types in the western United States. Riparian habitat is critical for up to 80% of terrestrial vertebrate species, and is especially important in the arid West. Estimates have placed riparian habitat loss at greater than 95% in most western states. Impacts to riparian ecosystems are reviewed along with mitigation and conservation recommendations for resource managers.

Many agricultural pesticides and industrial contaminants are capable of adversely affecting birds through direct effects such as elevated mortality rates and decreased reproductive success or indirectly by modifying habitat composition or food availability. Although neotropical migrants are potentially exposed to these contaminants on their breeding, migratory and wintering habitats, the impact of pollutants on population declines of migrant species is poorly understood. We revjew the effects of these contaminants on birds, evaluate the ability of current monitoring techniques to detect...

The Merriam's wild turkey (Meleagris gallopavo merriami) is a bird of the western United States. Early naturalists found it here. This is where its range has been expanded through transplants. This is where it has become a valuable sport hunting and aesthetic resource. This is where it must be managed. To understand Merriam's wild turkey management, one must understand the ecology of the West.

If persistence of migrant populations depends on the ability to find favorable conditions for survival throughout the annual cycle, factors associated with the en-route ecology of migrants must figure in any analysis of population change and in development of a comprehensive conservation "strategy." We view en-route habitat selection as a hierarchical process. Once migration routes are recognized and geographical variability in the route and timing are documented, important stopover habitat for Neotropical migrants can be delimited. The continent-wide pattern of migration concentrates...

Loss of tropical broadleaved forests and concurrent population declines of long-distance migratory birds in temperate breeding areas have been closely linked in both scientific and popular literature; however, little evidence of a causal association currently exists. We review the current land use situation in the neotropics, the projected outcome of deforestation early in the 21st century, and the extent of knowledge of migratory bird habitat use on the wintering grounds. From that information, we assess the likely current and future impact of deforestation on migratory birds, and examine...