MANAGEMENT OF INVASIVE SPECIES ISSUE STATEMENT

invasive or nuisance species is defined as a non-native plant or animal species that adversely affects the habitat and location they invade economically, environmentally, and/or ecologically.1Invasive species tend to dominate regions, particular habitats, and/or urban interface land with disturbed landscapes. The Sierra Nevada is one of the most biodiverse regions of the western United States. While the Sierra Nevada make up only twenty percent of the total land area of California, fifty percent of the native plant species in the state occur within this region (Shevock 1996). This diverse vegetation lends itself to a rich complement of wildlife within the numerous different ecosystem types that exist within the mountain range. Today this famed diversity is at risk due to alterations caused by human use, altered fire regimes, climate change, and invasions by non-native species following these human-caused alterations. In freshwater ecosystems, invasive species ’ greatest impacts are demonstrated through their alterations of native food webs, disruption to ecosystem function through predation and/or exclusion of native sensitive species, potential genetic weakening through hybridization with natives, degrading restoration efforts, and dominating the system as a monoculture. Their effects are often unknown and they may become unmanageable once established or naturalized. Research shows that many invasive plant species are in their early stages of invasion throughout the Sierra Nevada, compared with other regions 1 Invasive Species Definitions, available at