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Coral Reefs (2012) 31:11351148
DOI 10.1007/s00338-012-0937-5
REPORT
Fine-scale spatial genetic structure and clonal distribution of the cold-water coral Lophelia pertusa
M. P. Dahl R. T. Pereyra T. Lundalv
C. Andr
Received: 3 November 2011 / Accepted: 16 July 2012 / Published online: 2 August 2012 Springer-Verlag 2012
Abstract Determining the spatial genetic structure within and among cold-water coral populations is crucial to understanding population dynamics, assessing the resilience of cold-water coral communities and estimating genetic effects of habitat fragmentation for conservation. The spatial distribution of genetic diversity in natural populations depends on the species mode of reproduction, and coral species often have a mixed strategy of sexual and asexual reproduction. We describe the clonal architecture of a cold-water coral reef and the ne-scale population genetic structure (\35 km) of ve reef localities in the NE
Skagerrak. This study represents the rst of this type of analysis from deep waters. We used thirteen microsatellite loci to estimate gene ow and genotypic diversity and to describe the ne-scale spatial distribution of clonal individuals of Lophelia pertusa. Within-population genetic diversity was high in four of the ve reef localities. These four reefs constitute a genetic cluster with asymmetric gene ow that indicates metapopulation dynamics. One locality, the Sacken reef, was genetically isolated and depauperate. Asexual reproduction was found to be a highly important mode of reproduction for L. pertusa: 35 genetic individuals
were found on the largest reef, with the largest clone covering an area of nearly 300 m2.
Keywords Cold-water coral Clonality
Spatial genetic structure Genotypic diversity
Connectivity Conservation genetics
Introduction
Genetic diversity within and among populations is inuenced by the species mode of reproduction. Sexual reproduction resulting in recombination increases genetic diversity within populations, while dispersal of larvae connects populations. In contrast, clonal reproduction (asexual), which lacks sexual recombination, may decrease diversity, potentially hampering adaptation to environmental change (Lasker and Coffroth 1999). On the other hand, clonal propagation allows organisms to produce progeny without sexual reproduction and thus enables species to persist when unable to complete the sexual reproductive life cycle (Honnay and Bossuyt 2005). Clonal propagation also allows genetic individuals to spread out by clonal growth and to monopolize resources locally (Pan and Price 2002). Nevertheless, all species that are considered clonal have some level...