Population biology of the sea star Anasterias minuta (Forcipulatida: Asteriidae) threatened by anthropogenic activities in rocky intertidal shores of San Matías Gulf, Patagonia, Argentina

GREGORIO BIGATTI; MARIA BAGUR; L. P. ARRIBAS; PALOMO MARIA GABRIELA; MARIA BAGUR; PALOMO MARIA GABRIELA; GREGORIO BIGATTI; L. P. ARRIBAS

REVISTA DE BIOLOGíA TROPICAL

REVISTA DE BIOLOGIA TROPICAL

Lugar: Turrialba; Año: 2017 vol. 65 p. 73 - 84

0034-7744

In Patagonian coastal areas, intertidal benthic communities are exposed to extreme physical conditions.The interaction between harsh environment and anthropogenic pressure can generate changes in populationbiology of marine invertebrates, like density and reproduction. The oral brooding sea star Anasterias minutais a key organism in food chains of Atlantic Patagonian rocky intertidals, hence changes on its populationstructure can negatively affect shore communities. We studied the population biology of A. minuta and assessthe effect of environmental parameters and anthropogenic activities on its population on rocky intertidal shoresof San Matías Gulf, Patagonia, Argentina. Seasonal sea surface temperature, pH, salinity, water velocity, desiccationrate, boulders density, and anthropogenic influence (tourists and octopus fishermen) were recorded. In siteswith less tourist influence and high refuge, an increase in density was recorded, especially during the summer.Brooding individuals were found in fall and winter, while feeding individuals were observed in all seasons (12different prey, mainly the molluscs Tegula patagonica and Perumytilus purpuratus). Environmental variablessuch as boulders density and water velocity were the most important predictor of variation in population structure.Tourism and pH were the most important variables negatively correlated with density. Rev. Biol. Trop.65(Suppl. 1): S73-S84. Epub 2017 November 01.