Pacific Northwest Invasive Species

Since the first settlers traveled to the Pacific Northwest, people have enjoyed the scenic landscapes full of native plants and animals. The scenic landscapes rely on small ecosystems created by native plants and animals to forge their breathtaking views. However, a battle between native and invasive species has incited. These invasive species are detrimental to the ecosystems of the Pacific Northwest. Such foreign plants and animals often thrive in the Pacific Northwest, but greatly harm the native species and the surrounding ecosystems in the process. In order to understand this complex issue, the definition of an invasive species must be understood. Definitions of invasive species have been inconsistent, which has led to confusion within

Intentional introductions are those where a species is transported beyond its native range with the intention that it will become established. Intentional introductions with subsequent escape are those where the newly transplanted species escapes into the wild, spreading more than previously wanted. An unintentional introduction is one where an invasive species is transported, without detection, beyond its native range in an unrelated activity. For example, zebra mussels were first transported in ballast water and fire ants on cattle boats. Interestingly, on 1,364 nonnative species, 22% of intentional introductions proved to be harmful in some way, while 47% of unintentional introductions were harmful (Office of Technology Assessment; Fig. 1). Often times, an unintentional invasion is caused by trade and importation of goods. Ships often carry non-native species both on the exterior body and in the ballast water. Importation of pets, woods, and ornamental flowers also can result in the spread of invasive species. Often times, insects, microbes, and other invasive species can be transported in the United States via importation of goods (“Invasive Species”). For example, Feral Swine were brought to Oregon as livestock animals, but soon showed to have many negative effects on the ecosystems of Oregon. The foraging and rooting activities of these animals, has led to weed invasion, erosion, and change in the dominant vegetation types within the area (“Invasive Animals”). No matter how an invasive species is introduced, it must possess certain traits to be able to outcompete the native species for the precious resources within a