Chapter 5: Riparian Restoration through Grazing Management: Considerations for Monitoring Project Effectiveness
Alvin L. Medina, John N. Rinne, and Philip Roni
Many riparian areas throughout the United States were altered by the European settlement and the westward migration. Riparian areas currently comprise 1–5% of the landscape in the conterminous United States (Swift 1984; Knopf 1988), depending on the region. Their use is disproportionate to their relative extent and resource value. Swift (1984) estimated about 67 million riparian acres existed before European settlement. These areas were obligate settlement locations because of the presence of water. By the early twentieth century, the demand for surface water initiated a period of water resource development for irrigation, hydropower, and flood control. These early impacts were followed, midcentury, by mining (extraction) of subsurface waters to provide for rapidly developing metropolitan areas. Rivers and streams were dammed or diverted, and wetlands were drained, resulting in a drastic reduction in riparian habitats.
The settlement of rural areas included livestock grazing in riparian areas. The demand for beef increased as the population grew and as urban centers expanded in the late 1800s and early 1900s. Wild ungulates (e.g., bison Bison bison, elk Cervus elaphus, deer Odocoileus spp.) were a limited and unreliable food source for a developing nation; hence, livestock were extensively substituted. In the late 1800s, livestock in the West numbered in the millions and, coupled with drought, depleted vegetative resources across the landscape, including water-rich wetlands (Hendrickson and Minckley 1984) and riparian areas (Young 1998). Although the U.S. Forest Service recognized the need to control livestock numbers on public lands, not until the 1934 Taylor Grazing Act was livestock grazing management affected on public lands.