title: A tale of two seas: contrasting patterns of population structure in the small-spotted catshark across Europe.
abstract: Elasmobranchs represent important components of marine ecosystems, but they can be vulnerable to overexploitation. This has driven investigations into the population genetic structure of large-bodied pelagic sharks, but relatively little is known of population structure in smaller demersal taxa, which are perhaps more representative of the biodiversity of the group. This study explores spatial population genetic structure of the small-spotted catshark (Scyliorhinus canicula), across European seas. The results show significant genetic differences among most of the Mediterranean sample collections, but no significant structure among Atlantic shelf areas. The data suggest the Mediterranean populations are likely to have persisted in a stable and structured environment during Pleistocene sea-level changes. Conversely, the Northeast Atlantic populations would have experienced major changes in habitat availability during glacial cycles, driving patterns of population reduction and expansion. The data also provide evidence of male-biased dispersal and female philopatry over large spatial scales, implying complex sex-determined differences in the behaviour of elasmobranchs. On the basis of this evidence, we suggest that patterns of connectivity are determined by trends of past habitat stability that provides opportunity for local adaptation in species exhibiting philopatric behaviour, implying that resilience of populations to fisheries and other stressors may differ across the range of species.
authors.affiliation: School of Environment and Life Sciences , University of Salford , Salford, Greater Manchester M5 4WU, UK.
authors.forename: Chrysoula
authors.initials: C
authors.lastname: Gubili
authors.affiliation: Marine Biological Association of the United Kingdom, The Laboratory, Plymouth PL1 2PB, UK.
authors.forename: David W
authors.initials: DW
authors.lastname: Sims
authors.affiliation: CIBIO-U.P., Centro de Investigação em Biodiversidade e Recursos Genéticos, Campus Agrário de Vairão, Rua Padre Armando Quintas, Vairão 4485-661, Portugal.
authors.forename: Ana
authors.initials: A
authors.lastname: Veríssimo
authors.affiliation: CNR-IAMC Località Sa Mardini, Torregrande 09170, Italy.
authors.forename: Paolo
authors.initials: P
authors.lastname: Domenici
authors.affiliation: Centre for Environment, Fisheries and Aquaclture Science (CEFAS), Pakefield Road, Lowestoft, Suffolk NR33 0HT, UK.
authors.forename: Jim
authors.initials: J
authors.lastname: Ellis
authors.affiliation: Cretaquarium, Thalassocosmos, Hellenic Centre for Marine Research (HCMR), PO Box 2214, Heraklion Crete 71003, Greece.
authors.forename: Panagiotis
authors.initials: P
authors.lastname: Grigoriou
authors.affiliation: Center for Marine Biodiversity and Conservation, Scripps Institution of Oceanography 0202 , University of California , 9500 Gilman Drive, San Diego, CA 92083-0202, USA.
authors.forename: Andrew F
authors.initials: AF
authors.lastname: Johnson
authors.affiliation: Marine and Estuarine Ecology Unit , School of Biological Sciences, University of Queensland , Brisbane, Queensland 4072, Australia.
authors.forename: Matthew
authors.initials: M
authors.lastname: McHugh
authors.affiliation: Marine Scotland-Science, Marine Laboratory, PO Box 101, Aberdeen AB11 9DB, UK.
authors.forename: Francis
authors.initials: F
authors.lastname: Neat
authors.affiliation: CNR-IAMC Località Sa Mardini, Torregrande 09170, Italy.
authors.forename: Andrea
authors.initials: A
authors.lastname: Satta
authors.affiliation: ISMAR-CNR-Istituto di Scienze Marine, Consiglio Nazionale delle Ricerche, Largo Fiera della Pesca 2, Ancona 60125, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Scarcella
authors.affiliation: Departamento do Mar e Recursos Marinhos, IPMA , Instituto Português do Mar e da Atmosfera , Av. Brasilia, Lisboa 1449-006, Portugal.
authors.forename: Bárbara
authors.initials: B
authors.lastname: Serra-Pereira
authors.affiliation: Department of Marine Studies , University of Split , Livanjska 5, Split 21000, Croatia.
authors.forename: Alen
authors.initials: A
authors.lastname: Soldo
authors.affiliation: School of Biological Sciences , University of Bristol , Bristol Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK.
authors.forename: Martin J
authors.initials: MJ
authors.lastname: Genner
authors.affiliation: Marine Biological Association of the United Kingdom, The Laboratory, Plymouth PL1 2PB, UK ; School of Biological Sciences , University of Bristol , Bristol Life Sciences Building, 24 Tyndall Avenue, Bristol BS8 1TQ, UK.
authors.forename: Andrew M
authors.initials: AM
authors.lastname: Griffiths
keywords: Scyliorhinidae; elasmobranch; fisheries management; lesser spotted dogfish; sex-biased dispersal