Population genetic structure of the snow crab (Chionoecetes opilio) at the Northwest Atlantic scale

Marine species with planktonic larval durations of several months (teleplanic larvae) can potentially maintain demographic connectivity across large geographical distances. This perspective has important fundamental and applied implications, notably for the understanding of evolutionary and ecological processes in the marine realm, the implementation of marine protected areas, and fisheries management. Here we present, at the scale of the Northwest Atlantic, a spatial analysis of snow crab (Chionoecetes opilio, Majoidea) population genetic structure, a species that has a planktonic larval phase of 3 to 5 months. Eight microsatellite markers analysed on 847 C. opilio samples from 13 locations revealed an absence of significant genetic structure along the west coast of Greenland and within Atlantic Canada from southern Labrador to Nova Scotia. These results are consistent with a scenario of extensive demographic connectivity among C. opilio populations and have implications for the management of this species, which supports one of the most important Canadian and Greenlandic fisheries in terms of economic value. A genetic break is nevertheless identified between Greenland and Atlantic Canada, showing that genetic structure can develop within seas (the Labrador Sea in this case) despite the occurrence of very long planktonic larval stages.

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Defining conservation units in a rich and fragmented flora: implications for the management of genetic resources and evolutionary processes in south-west Australian plants

Australian Journal of Botany ◽

10.1071/bt99018 ◽

2000 ◽

Vol 48 (3) ◽

pp. 329 ◽

Cited By ~ 63

Author(s):

David J. Coates

Keyword(s):

Genetic Structure ◽

Species Diversity ◽

Population Genetic Structure ◽

Population Genetic ◽

Conservation Strategies ◽

The South ◽

Conservation Units ◽

Ecological Processes ◽

South West ◽

Australian Flora

The south-west Australian flora shows a diverse array of evolutionary patterns and exceptionally high species diversity. A significant component of this flora consists of relictual species which often have naturally fragmented and geographically restricted distributions. Many of these species appear to apportion significant levels of genetic diversity among populations. Diversity at both the population and species level presents a major challenge to the development of appropriate conservation strategies for this flora. To be effective these strategies should not only aim to preserve current levels of species diversity, but also consider intraspecific variation and the evolutionary and ecological processes associated with the generation and maintenance of that variation. The identification and characterisation of conservation units, based on population genetic structure and phylogeographic patterns within species, provide a useful basis upon which more general conservation principals can be developed for the maintenance of these processes. Population genetic structure and phylogeographic studies are used to show how conservation units can be identified in Lambertia orbifolia, Acacia anomala, Stylidium coroniforme, Stylidium nungarinense and Banksia cuneata, and taxa from a range of other genera. Determining conservation units in these taxa defines not only suitable units for their conservation but also the appropriate geographical scale for management. These findings indicate the potential this approach can have in determining strategies and priorities for the conservation of the south-west Australian flora.

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