Testing macroecological hypotheses in sandy beach populations: the wedge clam Donax hanleyanus in South America

RISOLI, MC; PIOLA, AR; DEFEO, O; LUZZATTO, D; CELENTANO, E; LOMOVASKY, BJ

MARINE ECOLOGY PROGRESS SERIES

INTER-RESEARCH

Lugar: Oldendorf/Luhe; Año: 2023 vol. 707 p. 43 - 56

0171-8630

Large-scale spatial and temporal variability in environmental conditions may result in differences in life history traits, population demography, and abundance of sandy-beach species. Here we analyze the effects of salinity, chlorophyll-a (Chl-a), and sea surface temperature (SST) on population parameters of the wedge clam Donax hanleyanus from 75 South American sandy beaches covering a 15°-latitude range. Generalized modeling results showed that between-beach differences in abundance, population structure, growth performance, productivity, mortality, and individual shell mass were mainly explained by salinity fluctuations, with Chl-a and SST as secondary contributors, overriding, in most cases, local habitat features (Dean’s parameter, grain size, slope). Our results provide valuable insights into macroscale ecological processes, setting a basis to delineate conservation guidelines at large spatial scales that respond to the potential effects of climate variability and change on sandy beach populations.