The native range of the blue crab Callinectes sapidus spans Nova Scotia to northern Argentina. In the US, it constitutes a keystone species in estuarine habitats of the Atlantic coast and Gulf of Mexico (GOM), serving as both predator and prey to other species, and also has historically represented a multi-billion dollar fishery. Knowledge relevant to effective management and monitoring of this ecologically and economically important species, such as levels of population genetic differentiation and genetic diversity, is necessary. Although several population genetics studies have attempted to address these questions in one or more parts of its distribution, conflicting results and potential problems with the markers used, as well as other issues, have obscured our understanding on them. In this study, we examined large-scale genetic connectivity of the blue crab in the US, using 16 microsatellites, and genotyped individuals from Chesapeake Bay, in the US Atlantic, and from nine localities along the US GOM coast. Consistent with the high long-distance dispersal potential of this species, very low levels of genetic differentiation were detected for the blue crab among the ten US localities examined, suggesting it constitutes a large panmictic population within this region. Estimations of genetic diversity for the blue crab appear to be high in the US, and provide a baseline for monitoring temporal changes in this species. Demographic analyses indicate a recent range expansion of the US population, probably during the Holocene. In addition, capitalizing on published microsatellite data from southern Brazil, our analyses detected high genetic differentiation between localities in the US and Brazil. These results point to the need for examination of genetic diversity and differentiation along the area spanning the US to southern Brazil.
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The Convention on Biological Diversity (CBD) currently serves as the multilateral environmental framework for protecting biodiversity. Parties to the CBD are required to develop and submit National Biodiversity Strategies and Action Plans (NBSAPs) and National Reports. These documents serve as the instruments used by governments and stakeholders to identify their priorities, implement, and track progress to the CBD. The International Union for Conservation of Nature (IUCN) has produced biodiversity and conservation knowledge products that are fundamental for tracking the progress of targets such as the Aichi Biodiversity Targets. We examined if countries in the Americas are using knowledge products based on IUCN standards to help construct their documents; 234 documents were analyzed for knowledge product keywords. The IUCN Red List of Threatened Species was mentioned in 91.8% of keyword-coded segments. IUCN publications, Protected Areas Categories, Key Biodiversity Areas, the Red List of Ecosystems and World Database on Protected Areas had 8.2% of the remaining segments. Further studies should investigate awareness of knowledge products among national focal points for the CBD to determine their limited use in document development. IUCN knowledge products should continue to form an integral part of future indicators during this critical moment for biodiversity conservation.
The Global Mammal Assessment (GMA) evaluates the risk of extinction for all species of mammals, providing important data on their status to national and global conservation agencies and conventions. We assessed all of the species of Brazilian rodents as part of the GMA activities of the International Union for the Conservation of Nature Species Survival Commission (IUCN SSC) Small Mammal Specialist Group. A total of 234 species were evaluated against the IUCN Red List Criteria and placed into one of eight categories. Although rodents do not have elevated extinction risk compared to mammals as a whole, several families of caviomorph rodents have high levels of either threat, data deficiency, or both. The family Echimyidae has a large number of species and one-third of those either are species of conservation concern or data deficient. The family Ctenomyidae also is of concern in this regard. There are also strong geographic patterns to threat and poor knowledge. The focal areas for conservation effort are the Atlantic Forest and the Cerrado, and for Data Deficient species Atlantic Forest, Cerrado, and Amazonia, in particular the eastern Amazon. The results highlight the need for targeted field research and the application of ecological and spatial data to the development of conservation actions.
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