دانلود رایگان مقاله استراتژی مقابله با تهدید ناشی از حفاظت ورود ژنتیکی و هیبریداسیون

Abstract

Hybridization poses a complex problem for biodiversity conservation but there has been little discussion of strategies and guidelines designed to address it from a management perspective. In this article I review management approaches aimed at addressing hybridization while highlighting outstanding needs. Despite real-world efforts to manage systems in which hybridization is a concern, there has been little effort to develop broadly applicable guidelines or best management practices. Management programs would be enhanced by the characterization of the patterns and processes of hybridization in nature and integrating those into planning and policy. Doing so facilitates the development of holistic strategies that balance the importance of hybridization in many biological systems while addressing situations in which human-facilitated gene flow causes concern. The shift from reactive management to emphasizing measures designed to prevent hybridization from becoming a threat has been a positive development. Examples include assessing the genetic characteristics of populations used in translocation programs. Overlooked, however, has been the management of stable hybrid systems in which the goal is not necessarily preventing intermixing but protecting stabilizing mechanisms through policy and land use management. When hybridization emerges as a legitimate threat, activities such as culling, spatial isolation, targeted harvest, and de-introgression can protect threatened genomic units. Further experimentation of these techniques and collaboration among scientists and managers will provide lessons for establishing general guidelines for the conservation community. I hope this review stimulates discussion about approaches useful for addressing hybridization and promotes further development of new techniques and frameworks.

7. Conclusion

The challenges posed by hybridization have limited the development of tools and recommendations that can be exploited by managers and policymakers. There are few institutions with formal policies or action plans specifically addressing hybridization. Most that does exist focuses on prevention. For example, the IUCN Reintroduction Specialist Group has recommendations for using native sources for reintroduction and translocation programs (IUCN/SSC, 2013). Review of salmon hatchery practices in the Pacific Northwest of the United States promoted a series of propagation strategies to minimize genetic homogenization of wild salmon populations (Mobrand et al., 2005; Paquet et al., 2011). A limited number of government agencies and conservation organizations based in Canada and the United States have formal policies regarding hybrid management (Jackiw et al., 2015). Formal adoption of recommendations and policies regarding preventative hybrid management, especially in the context of natural systems, would enhance conservation efforts. Even more pressing is the need to develop guidelines for actually managing systems when hybridization is a conservation concern. Many tactics, such as culling and spatial isolation, have been implemented but there are few recommendations about their utility and feasibility under different scenarios.