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1. [Article] Feral Swine Action Plan for Oregon
Feral swine are defined as free roaming animals of the genus Sus that are not being held under domestic management or confinement. Swine have spread from Europe and Russia to habitats around the world ...Citation Citation
- Title:
- Feral Swine Action Plan for Oregon
- Author:
- Sytsma, Mark, Rouhe, Arick Christopher
- Year:
- 2007
Feral swine are defined as free roaming animals of the genus Sus that are not being held under domestic management or confinement. Swine have spread from Europe and Russia to habitats around the world via human introduction. Currently, feral swine populations are established on every continent except Antarctica. Unlike other large mammal invaders, swine have a high reproductive capacity and are omnivorous, which allows for a quick assimilation into most habitats. Once a breeding population is established in an area, the population can quickly increase and negatively impact the ecosystem. A successful invasion of feral swine is difficult, and sometimes impossible, to reverse. A feral swine pest risk assessment for Oregon, released in 2004, designated feral swine as a very high-risk species due to high potential for establishment, environmental and economic impacts, and disease transmission to wildlife, livestock and humans. Economic impacts on ecosystems and disease transmission to wildlife are difficult to assess, but restoration of ecosystems and losses to agriculture and livestock have been estimated to exceed US$800 million in the United States each year. Environmental impacts include facilitation of noxious weed invasions, shifts in dominant plant species, reduction of forest regeneration, and soil erosion. Facilitation of noxious weeds and erosion due to feral swine rooting are documented in Oregon. Feral swine in Oregon have not been implicated in disease transmission to humans, but the recent E. coli outbreak from spinach grown on a California farm that caused three deaths has been genetically traced to feral swine excrement deposited in spinach fields. The feral swine population in Oregon is currently small and dispersed. Few disturbances have been documented but state and federal biologists report regular occurrence of disturbances due to feral swine. Actions to prevent the effects of an invasion fall into three categories: management, control or eradication. Of the three categories, only eradication efforts have successfully slowed or reversed the effects of swine invasions. Case studies from California, Australia, Hawaii, the Galapagos Islands and the Channel Islands off the coast of California show that management and control efforts, while effective in the short term, have not successfully kept small feral swine populations from increasing to levels that are unmanageable and uncontrollable. A four-year feral swine eradication plan is proposed. The Plan includes recommended legislative changes to facilitate eradication, outreach and education, population assessment, rapid response, and eradication elements. A 0.5 FTE position is required at the Oregon Department of Fish and Wildlife to implement the plan. Eradication of feral swine in Oregon is estimated to require a four-year, $1.29 million effort. Follow-up control of new releases and escapes will require a maintenance effort estimated at less than $50,000 per year (excluding contingency funds for emergency response). These costs are small relative to the value of the $3.6 billion Oregon agriculture and livestock industries and the investment Oregon has made in riparian restoration efforts. Sustained control of feral swine in Oregon will require a longterm commitment that will include annual domestic swine marking, education, and monitoring.
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The nutria (Myocastor coypus) is a large semi-aquatic mammal native to South America that has been introduced to numerous countries around the world, primarily for fur farming. Nutria were introduced in ...
Citation Citation
- Title:
- Report on Nutria Management and Research in the Pacific Northwest
- Author:
- Sheffels, Trevor Robert, Sytsma, Mark
- Year:
- 2007
The nutria (Myocastor coypus) is a large semi-aquatic mammal native to South America that has been introduced to numerous countries around the world, primarily for fur farming. Nutria were introduced in Oregon and Washington in the 1930s, and feral populations were documented in 1943. Populations are known to be expanding in both Oregon and Washington, and regional nutria damage and nuisance complaints have increased in recent years. Most of the extensive damage caused by nutria is a direct result of feeding and burrowing, but nutria are also capable of transporting parasites and pathogens transmittable to humans, livestock, and pets. Although several past regional and local nutria research and management projects have been identified, there is a shortage of nutria information from the Pacific Northwest considering that the species has been present in the region for approximately seventy years. The Center for Lakes and Reservoirs (CLR) at Portland State University (PSU), in partnership with several local, state, and federal agencies, has taken the lead in addressing the regional nutria problem. Activities completed to date include a regional nutria management workshop, the ongoing development of a regional nutria distribution/density map, and a research project to analyze the impact of nutria herbivory on regional riparian wetland habitat restoration projects. In addition, the CLR at PSU is participating in the development of the national Aquatic Nuisance Species Task Force nutria management plan. This initial assessment of the current nutria situation in the Pacific Northwest conducted by the CLR at PSU has revealed that regional nutria problems are more extensive than previously realized. Nutria sightings have now been confirmed from the Canadian border to near the southern border of Oregon, confirming a larger range than was previously known. It was also found that the main nutria issues in the Pacific Northwest differ from the main nutria issues in Louisiana and Maryland. For example, the most significant category of regional nutria damage appears to be the destruction of water control structures and associated erosion caused by nutria burrowing, as opposed to nutria herbivory damage in Louisiana and Maryland. Another unique situation in the Pacific Northwest is the high density of nutria populations in urban areas, increasing the potential for conflicts between nutria and humans. Nutria attacks have been reported in isolated cases, and nutria are rodents that carry a variety of transmittable parasites and pathogens. It has also been confirmed that significant regional nutria herbivory damage does occur at some locations. Fortunately, it has become evident through the course of this assessment that a strong regional interest to address the nutria problem exists. A wide variety of agencies and organizations across the region are being negatively impacted by nutria, and these entities are ready to move forward to develop a feasible solution. To date, small-scale nutria management and eradication efforts have been somewhat effective temporarily, but a more permanent solution requires that the situation be addressed on a much larger scale. Due to the long period of time since the initial nutria introduction, the extent of current regional nutria populations, and the changing climate patterns, a long-term effort will likely be required to effectively address the regional nutria issue. The most immediate management need is to develop an official regional nutria management plan with the focus of greatly reducing the amount of damage being caused by this invasive rodent and preventing further population growth and expansion. The effectiveness of initial management efforts will shed light on how to adapt management strategies in the future and whether or not regional eradication is a feasible option. Continued nutria research and the development of coordinated management efforts at the regional scale are vital in order to bring the current regional nutria problem under control. The CLR at PSU has developed initial recommendations to help guide the process of determining how to most effectively manage nutria in the Pacific Northwest. First and foremost, funding sources for continued work on the regional nutria problem must be found. Once funding is secured, the development of an official nutria regional management plan is crucial. Priorities connected with the management plan would include creating an early detection rapid response plan, identifying best management practices, initiating a pilot eradication program, and identifying priority research needs. Potential research studies include a long-term pilot eradication project at the watershed level, relationships between climate change and regional nutria dispersal, and the dynamics of nutria-muskrat interactions. It is also evident that further coordination between local, state, and federal agencies is necessary to delegate responsibilities and keep all parties updated. The creation of a central regional database and appropriate agency protocols could be used to collect information about nutria damage and associated economic impacts. Current laws and regulations pertaining to nutria should be enforced and possibly updated so that Oregon and Washington laws are uniform. Finally, it is important to inform the public about current nutria issues and utilize resources the general public can potentially provide.