Integrative assessment of intraspecific diversification in Loggerhead Shrike (Lanius ludovicianus) provides insight on the geographic pattern of phenotypic divergence and process of speciation

Integrated studies of the geographical, ecological, and historical factors that shape intraspecific phenotypic and genetic variation can help us to decipher the processes leading to geographic patterns of population divergence and speciation. We quantify and compare morphological and genetic variation in the Loggerhead Shrike (Lanius ludovicianus Linnaeus, 1766), a broadly distributed passerine in North America with both migratory and non-migratory populations that occupy a diversity of habitats and topographies. The geographic distributions and patterns of differentiation among subspecies suggest that migration has strongly impacted population divergence, including the habit of migrating itself, but also dispersal. Patterns of mitochondrial and nuclear genetic differentiation can be attributed to female-biased dispersal and to increased dispersal rates and distances in migratory populations. Weak phenotypic differentiation among migratory versus migratory and non-migratory populations suggest that migration may more strongly affect morphology than adaptation to local habitats. Our results generally support previous subspecific designations with two notable exceptions. We found little genetic differentiation between two subspecies (Lanius ludovicianus gambeli Ridgway, 1887 and Lanius ludovicianus mexicanus C.L. Brehm, 1854), but identify a new, distinct subspecies, which we refer to as Lanius ludovicianus centralis ssp. nov.

Bridging science and law across jurisdictions in Canadian species at risk policy : four case studies

1.0 Introduction -- 2.0 Methods -- 3.0 Federal Legal Measures for Species at Risk in Canada -- 4.0 Provincial Legal Measures for Species at Risk in Ontario -- 5.0 Ontario Species at Risk: Two Case Studies -- 6.0 Provincial Legal Measures for Species at Risk in British Columbia -- 7.0 British Columbia Species at Risk: Two Case Studies -- 8.0 Policy Recommendations -- 9.0 Conclusions and Applications for Future Research. The purpose of this thesis is to evaluate the effectiveness of current legal measures for protecting species at risk in Canada through an interpretive qualitative method. Four species case studies were analyzed: The Eastern Loggerhead Shrike, Jefferson Salamander, Northern Spotted Owl, and Vancouver Island Marmot. Policy recommendations for reforms arising from the research are: i) inter-jurisdictional cooperation is imperative for protecting species at risk; ii) dedicated species at risk legislation is crucial, and it is recommended that such legislation exist at both federal and provincial levels; iii) flexibility instruments and exemptions to existing law should be scientifically informed and used cautiously; iv) private landowners are significant stakeholders and stewardship efforts are important; v) scientific information and the definition of critical habitat for species at risk are crucial. The thesis concludes that a science-based precautionary approach to species protection is fundamental to address the plight of species at risk in Canada.

Bridging science and law across jurisdictions in Canadian species at risk policy : four case studies

1.0 Introduction -- 2.0 Methods -- 3.0 Federal Legal Measures for Species at Risk in Canada -- 4.0 Provincial Legal Measures for Species at Risk in Ontario -- 5.0 Ontario Species at Risk: Two Case Studies -- 6.0 Provincial Legal Measures for Species at Risk in British Columbia -- 7.0 British Columbia Species at Risk: Two Case Studies -- 8.0 Policy Recommendations -- 9.0 Conclusions and Applications for Future Research. The purpose of this thesis is to evaluate the effectiveness of current legal measures for protecting species at risk in Canada through an interpretive qualitative method. Four species case studies were analyzed: The Eastern Loggerhead Shrike, Jefferson Salamander, Northern Spotted Owl, and Vancouver Island Marmot. Policy recommendations for reforms arising from the research are: i) inter-jurisdictional cooperation is imperative for protecting species at risk; ii) dedicated species at risk legislation is crucial, and it is recommended that such legislation exist at both federal and provincial levels; iii) flexibility instruments and exemptions to existing law should be scientifically informed and used cautiously; iv) private landowners are significant stakeholders and stewardship efforts are important; v) scientific information and the definition of critical habitat for species at risk are crucial. The thesis concludes that a science-based precautionary approach to species protection is fundamental to address the plight of species at risk in Canada.