Wetlands and riparian areas between the Rocky Mountains and the Sierra Nevada are incredibly diverse and valuable habitats. More than 80 percent of the wildlife species in this intermountain region depend on these wetlands—which account for less than 2 percent of the land area—for their survival. At the same time, the wetlands also serve the water needs of ranchers and farmers, recreationists, vacation communities, and cities. It is no exaggeration to call water the "liquid gold" of the West, and the burgeoning human demands on this scarce resource make it imperative to understand and properly manage the wetlands and riverine areas of the Intermountain West.
This book offers land managers, biologists, and research scientists a state-of-the-art survey of the ecology and management practices of wetland and riparian areas in the Intermountain West. Twelve articles examine such diverse issues as laws and regulations affecting these habitats, the unique physiographic features of the region, the importance of wetlands and riparian areas to fish, wildlife, and livestock, the ecological function of these areas, their value to humans, and the methods to evaluate these habitats. The authors also address the human impacts on the land from urban and suburban development, mining, grazing, energy extraction, recreation, water diversions, and timber harvesting and suggest ways to mitigate such impacts.
Water in the western United States has been referred to as "liquid gold." The overappropriation of most streams is a testament to the value of water and a source of conflict. Water flowing from a typical mountain range in the Rocky Mountains is often used for multiple purposes: for fish and wildlife habitat, for irrigation and stock watering, for municipal and industrial purposes, and even for ornamental displays. The Intermountain West is an incredibly diverse area that occupies a large portion of the United States (Figure I.1). The area varies from mountains where snow and summer rains feed high-elevation wetlands to arid basins where natural systems depend upon mountain runoff and spring storms. Throughout the Intermountain West, wetlands and riparian areas perform functions far out of proportion to the area that they cover. As an example, wetland and riparian areas in Wyoming, Nevada, and Montana comprise less than 2% of the surface area, yet more than 80% of wildlife species in those states depend on these areas to fulfill life requirements. Wetlands in the Intermountain West are no less important than estuarine wetlands, prairie potholes, or forested wetlands of the Midwest, and yet scant attention has been focused on them. Part of the problem has been the relatively sparse human population and its associated impacts that usually drive research and information needs. However, this is rapidly changing in the Intermountain West, where many towns and cities have expanded within the past two decades. For example, Denver, Boise, and Phoenix have doubled in population since 1985. This population boom is not restricted to large metropolitan areas but extends also to towns like Buffalo, Wyoming; Durango, Colorado; and Moab, Utah. As conflicts involving wetland and riparian areas of the Intermountain West increase, so will the need for information about them.
We believe there is a need for a book that reviews these unique habitats and identifies areas on which future research should focus. With that goal in mind, we have organized this book to encompass legal issues, a description of the region, riverine habitats, natural palustrine habitats, created palustrine habitats, and evaluation.
The first chapter covers laws and regulations that apply to wetland and riparian areas of the western United States. Important case law is reviewed with respect to its impacts on current and future regulations and management issues. While some may find legal issues difficult to follow and out of their realm of interest, we feel that they are critical in understanding how management decisions are made regarding wetland and riparian habitats in the West. In this regard, the authors have done an excellent job of putting the legal concerns into laymen's terms.
The second chapter offers an in-depth description of the area that is called the Intermountain West. Throughout the development of the book we struggled with defining our area of coverage and the research that pertains to wetlands and riparian areas within this region. In several instances throughout the volume, authors discuss research in areas outside of the Intermountain West. We allowed this only where we felt that the work was applicable to areas within the Intermountain West. Murray Laubhan's chapter helped to define our focus and gives the reader insight into the formative geological, meteorological, and ecological forces that shape wetland and riparian habitats in the Intermountain West.
The third section, chapters 3-5, encompasses the ecology and management of riverine wetlands. We recognize that riparian/riverine systems are actually wetlands and are considered as such under many classification schemes. However, we have kept them separate because of their importance and the influence they have on politics, management, and ecology in the Intermountain West. In this section, as in the following two sections, we have included chapters that cover ecosystem function, important taxa associated with these habitats, and issues that are important when managing these areas.
The fourth section, chapters 6-8, covers natural palustrine habitats, areas that traditionally have been the mainstay of wetland habitat and management. Palustrine wetlands are those areas that can support rooted aquatic vegetation, have anaerobic soils, and are flooded during portions of the year. While the Intermountian West is considered a dry region, it has a surprisingly large number of natural wetlands, especially in basins between the mountain ranges. This section not only assists the manager in identifying techniques to manage these areas but also helps the ecologist gain understanding of how they function.
The fifth section, chapters 9-11, covers created palustrine habitats, a subject that has been neglected in most wetland texts. Wetland creation in the Intermountain West is often associated with other activities (e.g., stock pond construction, mining, irrigation), and these habitats can be very valuable. Created wetlands in the western United States number in the hundreds of thousands, and little is known about their function or value. The authors in this section provide excellent descriptions of the many types of created wetlands and suggest various management practices that can assist in making them more productive.
Finally, chapter 12 leads the reader through the many classification and evaluation techniques that can be used for wetlands and riparian areas of the Intermountain West.
While commendable work has been conducted on wetland and riparian areas within the Intermountain West, we believe that much more needs to be done. Areas of importance that are particularly lacking in research and understanding include vegetative community structure and function; the role of salinity in structuring wetland communities; the importance of hydrologic regimes and hydrology in general; nutrient cycling in wetlands (especially as it pertains to contaminants); impacts of dams on structure and function of adjacent wetlands; and development of successful techniques for wetland and riparian restoration. A considerable information gap exists with regard to created wetlands and the role they play ecologically, biologically, socially, and economically. It is our wish that this text will stimulate agencies and individuals to devote more time and resources to studying these issues.
This book serves as a good starting point for managers and researchers working with wetland and riparian areas in the Intermountain West. No single body of work, the present volume included, is the end point in any discipline. The Intermountain West is an incredibly diverse area, and to attempt to cover the ecology and management of all of its wetland and riparian areas would have been a mistake. If we have brought to light more management options and identified topics for future research, we will have accomplished our goal. Good luck in your endeavors.