Divergence and molecular variation in common whelkBuccinum undatum(Gastropoda: Buccinidae) in Iceland: a trans-Atlantic comparison

Abstract

The dispersal and history of species affects their genetic population structure at both small and large geographical scales. The common whelk, Buccinum undatum, is a widespread subtidal gastropod in the North Atlantic that has no planktonic larvae and has thus limited dispersal capacity. The snail, which has been harvested by humans for centuries, is highly variable in morphology. To evaluate the population structure in the rich fishing grounds in western Iceland and its divergence from samples across the Atlantic, genetic patterns based on sequence variation in two mitochondrial (mt)DNA genes (COI and 16S) and five microsatellites were studied and compared with variation in populations from both sides of the Atlantic. Significant differences in allele and haplotype frequencies were found among samples separated by short distances along the coast of Iceland. Partition of the variation showed larger variance among samples obtained from distant regions than from neighbouring sites and genetic distances were correlated with geographical distance among populations in Europe. Phylogeographic patterns in mtDNA reveal different monophyletic lineages on both sides of the Atlantic, which predate the onset of the Ice Age and which may constitute cryptic species. Similar micro-and macrogeographical patterns were observed for the mtDNA and microsatellite markers, despite high frequencies of null alleles. Bayesian skyline reconstructions of the demographic history and mismatch distributions suggest that, although sizes of some populations were unaffected by Ice Age glaciations, others show signs of expansion after the Last Glacial Maximum. These phylogeographical patterns are consistent with patterns expected for low dispersal species that have survived in allopatric glacial refugial populations on both sides of the Atlantic and in deep-sea refugia within each continent. The observed genetic structure has implications for conservation and sustainable management of the harvested populations.

Novel polymorphic microsatellite markers for Bellamya and their application in population genetics of three species

“…SSR markers have been widely used as highly effective DNA markers in the study of molluscan population genetics (Arthofer et al, 2011;Pálsson et al, 2014). In this study, 65 novel microsatellite loci were isolated and some of them were used to analyze the population genetics of Bellamya spp in China.…”

“…Microsatellite markers are a useful marker system for the analysis of the population genetics of many snail species (Arthofer et al, 2011;Pálsson et al, 2014;Rivero-Wendt et al, 2014). Gu et al (2012a,b) first developed SSR DNA markers for B. aeruginosa.…”

Anthropocene invasion of an ecosystem engineer: resolving the history ofCorophium volutator(Amphipoda: Corophiidae) in the North Atlantic

“…Although introductions from multiple sources can alleviate these bottlenecks, these mixed populations still exhibit a pattern of subsampling, with alleles identical to or closely descended from those found in more phylogenetically diverse indigenous populations (Geller et al ., ; Frankham, ; Hauber et al ., ; Lacoursière‐Roussel et al ., ; Cahill & Viard, ). By contrast, natural post‐glacial trans‐Atlantic dispersal is expected to result in a distribution including the intermediate landmasses of Iceland and Greenland and one or more monophyletic lineages on each side of the Atlantic (Krebes, Blank & Bastrop, ; Panova et al ., ; Palsson et al ., ) If C. volutator was recently introduced to the NWA from the NEA, we expect genetic diversity in the NWA to be a subsample from more phylogenetically diverse populations in the NEA. Consistent with this prediction, we found that all genetic diversity in the NWA was identical to or recently descended from that found in the NEA (Fig.…”

Whelk (Buccinum undatum L.) stocks around the Island of Jersey, Channel Islands: Reassessment and implications for sustainable management

“…The closed season has also resulted in some displaced effort, whereby French owners have expressed interest in buying Jersey-registered vessels to operate in Jersey exclusive waters during the French closed season, further increasing fishing effort upon Jersey whelk stocks. The recent study by Pálsson et al (2014) highlights the short larval dispersal and thus genetic difference of whelks populations on a relatively small scale and in turn, their sensitivity to overexploitation via displaced or concentrated fishing effort. We would thus suggest a joint closed season in both Jersey and France, at the same time of year.…”

“…However, studies in other regions around the UK and Europe have shown that once an area has been 'fished-out' it can take a relatively long time for the population to recover, if at all, as there is little inward migration of other whelks (Hancock, 1963;Himmelman and Hamel, 1993;Valentinsson et al, 1999). A recent study by Pálsson et al (2014) suggests that genetically different populations of common whelks can occur within small coastal areas, yet are independent of geographical or shortest distances on sea.…”