title: Consequences of variable larval dispersal pathways and resulting phenotypic mixtures to the dynamics of marine metapopulations.
abstract: Larval dispersal can connect distant subpopulations, with important implications for marine population dynamics and persistence, biodiversity conservation and fisheries management. However, different dispersal pathways may affect the final phenotypes, and thus the performance and fitness of individuals that settle into subpopulations. Using otolith microchemical signatures that are indicative of 'dispersive' larvae (oceanic signatures) and 'non-dispersive' larvae (coastal signatures), we explore the population-level consequences of dispersal-induced variability in phenotypic mixtures for the common triplefin (a small reef fish). We evaluate lipid concentration and otolith microstructure and find that 'non-dispersive' larvae (i) have greater and less variable lipid reserves at settlement (and this variability attenuates at a slower rate), (ii) grow faster after settlement, and (iii) experience similar carry-over benefits of lipid reserves on post-settlement growth relative to 'dispersive' larvae. We then explore the consequences of phenotypic mixtures in a metapopulation model with two identical subpopulations replenished by variable contributions of 'dispersive' and 'non-dispersive' larvae and find that the resulting phenotypic mixtures can have profound effects on the size of the metapopulation. We show that, depending upon the patterns of connectivity, phenotypic mixtures can lead to larger metapopulations, suggesting dispersal-induced demographic heterogeneity may facilitate metapopulation persistence.
authors: School of Biological Sciences, Victoria University of Wellington, PO Box 600, Wellington, New Zealand jeffrey.shima@vuw.ac.nz.
authors: Jeffrey S
authors: JS
authors: Shima
authors: Department of Biological Sciences, Florida Atlantic University, 3200 College Avenue, Davie, FL 33314, USA.
authors: Erik G
authors: EG
authors: Noonburg
authors: Department of Zoology, University of Melbourne, Melbourne, Victoria 3010, Australia.
authors: Stephen E
authors: SE
authors: Swearer
mesh_terms: D063147:Animal Distribution; D000818:Animals; D001823:Body Composition; D007814:Larva / Q000254:growth & development / Q000502:physiology; D008055:Lipids; D009520:New Zealand; D009792:Oceans and Seas; D010037:Otolithic Membrane / Q000737:chemistry; D010473:Perciformes / Q000254:growth & development / Q000502:physiology*; D010641:Phenotype; D011157:Population Dynamics
chemical_list: D008055:Lipids
keywords: connectivity; demographic heterogeneity; individual variation; larval dispersal; metapopulation; phenotype