Research Outputs

Now showing 1 - 4 of 4
  • Publication
    Non-indigenous species contribute equally to biofouling communities in international vs local ports in the Biobío region, Chile
    (Taylor & Francis, 2018)
    Leclerc, Jean-Charles
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    Viard, Frédérique
    ;
    ; ;
    Neira Hinojosa, José
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    Pérez Araneda, Claudia
    ;
    Silva, Francisco
    ;
    Growing coastal urbanization together with the intensification of maritime traffic are major processes explaining the increasing rate of biological introductions in marine environments. To investigate the link between international maritime traffic and the establishment of non-indigenous species (NIS) in coastal areas, biofouling communities in three international and three nearby local ports along 100 km of coastline in south-central Chile were compared using settlement panels and rapid assessment surveys. A larger number of NIS was observed in international ports, as expected in these ‘invasion hubs’. However, despite a few environmental differences between international and local ports, the two port categories did not display significant differences regarding NIS establishment and contribution to community structure over the studied period (1.5 years). In international ports, the free space could be a limiting factor for NIS establishment. The results also suggest that local ports should be considered in NIS surveillance programs in Chile.
  • Publication
    Bioenergetics of parental investment in two polychaete species with contrasting reproductive strategies: The planktotrophic Boccardia chilensis and the poecilogonic Boccardia wellingtonensis (Spionidae)
    (Marine Ecology, 2020)
    Doherty‐Weason, Daniel
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    Oyarzun, Fernanda
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    Vera, Luciano
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    Bascur, Miguel
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    Guzmán, Fabián
    ;
    Silva, Francisco
    ;
    ;
    The level of parental investment for larval nutrition may determine the life cycle in marine invertebrate species laying egg masses or capsules, where the food available for enclosed individuals would determine time and developmental stage of hatching. Most species show a unique type of larval development. However, few species are poecilogonous and combine more than one development type. Poecilogony, although scarcely studied, allows comparing different patterns of parental reproductive investment, without the phylogenetic effect of the species ancestral modes of development (phylogenetic inertia), to help to understand the factors determining life strategy evolution in marine invertebrates. The poecilogonous polychaete worm Boccardia wellingtonensis encapsulates and incubates its offspring, which then hatches as either planktotrophic larvae or benthic juveniles; while Boccardia chilensis shows a non‐poecilogonous reproductive type, producing only planktotrophic larvae. In this work, we estimated the bioenergetic and biochemical composition of brooding and non‐brooding females of B. wellingtonensis and B. chilensis to compare the costs of reproduction in these two species. Results showed that glucose, protein, lipid, and energy content were significantly higher in non‐brooding than in brooding females of B. wellingtonensis; but also contained significantly more glucose, protein, and lipid than females of B. chilensis (in absolute and relative dry weight values). The poecilogonous species showed higher energy content previous to laying offspring. Our results support the idea that the evolution of a certain reproductive and life history traits in marine invertebrates is related to adaptations in the female's reproductive investment.
  • Publication
    Development and characterization of microsatellite markers for the toadfish Aphos porosus
    (Springer, 2015)
    Silva, Francisco
    ;
    Hernández-Miranda, Eduardo
    ;
    The toadfish Aphos porosus is a coastal benthic-demersal fish from the Southeastern Pacific coast. This species exhibits parental care and low dispersal potential, and it is subjected to bycatch by artisanal and industrial fisheries, which make A. porosus a susceptible species in conservation terms. In this work we present 18 polymorphic microsatellite loci for this species. Allelic richness varied between 2 and 8 alleles and observed heterocigocity ranged between 0.026 and 0.737. Fourteen of the 18 loci were unlinked, polymorphic and in Hardy–Weinberg equilibrium. The non-exclusion probability over all loci was very low (0.0013). These loci show potential for population genetic analyses, for studying reproductive strategies and supporting conservation policies for this species.
  • Publication
    New polymorphic microsatellite markers for the pelagic fish Normanichthys crockeri
    (Springer, 2015)
    Silva, Francisco
    ;
    Hernández-Miranda, Eduardo
    ;
    The coastal pelagic fish Normanichthys crockeri inhabits the southeast Pacific coast and is a monotypic species of the Normanichthyidae family. Its ecologically and economic importance, and the high fishing pressure it is subjected to make N. crockeri an ideal target species for conservation. Here, we present 12 new hypervariable loci for this species. Allelic richness varied between 2 and 8 alleles, and observed heterozygosity ranged between 0.059 and 1.00. Two loci showed significant deviations from Hardy–Weinberg and revealed the presence of null alleles. These new loci have a high potential to be used in population genetics studies and fishery management plans.