Assessment of larval connectivity in a sandy beach mole crab through a coupled bio-oceanographic model

Published in	Estuarine, Coastal and Shelf Sciences, v. 246(5)
Authors	Meerhoff, E., Defeo, O., Combes, V., Franco, B.C., Matano, R.P., Piola, A.R.,
Publication year	2020
DOI	https://doi.org/10.1016/j.ecss.2020.107035
Affiliations	Unidad de Ciencias del Mar, Facultad de Ciencias, Universidad de la República, Montevideo, Uruguay College of Earth and Atmospheric Sciences, Oregon State University, USA. Centro de Investigaciones del Mar y la Atmósfera, Buenos Aires, Argentina Instituto Franco-Argentino sobre Estudios de Clima y sus Impactos, Buenos Aires, Argentina Departamento de Oceanografía, Servicio de Hidrografía Naval (SHN), Ciudad Autónoma de Buenos Aires, Argentina Departamento de Ciencias de la Atmósfera y los Océanos, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina División El Niño y Clima Oceánico, Instituto Oceanográfico de la Armada, Guayaquil, Ecuador. Instituto Milenio de Oceanografía (IMO), Proyecto IC 120019, Universidad de Concepción, Concepción, Chile.
IAI Program	CRN3
IAI Project	CRN3070
Keywords	Mole crab Larval connectivity Sandy beach Individual-based model
	Meerhoff_2020_CRN3070pip.pdf

Highlights

•Emerita brasiliensis larval connectivity was studied through individual-based models.

•12-year ROMS outputs were used to address connectivity in the coast of Uruguay.

•Connectivity changed drastically during La Niña event with intense northeasterly winds.

Abstract

The biophysical mechanisms influencing larval distribution and their impacts on the metapopulation dynamics of sandy beaches, particularly the connectivity patterns associated with larval dispersal, are poorly understood. Here, we identify larval connectivity patterns of the mole crab Emerita brasiliensis in the coast of Uruguay. A biophysical individual based model (IBM) of larval transport was coupled to a regional high-resolution physical model to estimate the monthly and interannual variation of larval connectivity, as well as the impact of the length of the reproductive period on it. Larval connectivity showed marked interannual variations, which were mainly related to interannual changes in seasonal winds and associated ocean circulation patterns, particularly during La Niña years. The southernmost area where E. brasiliensis occurs only received larvae from the nearest release area in November and January spawning events during a strong La Niña year, characterized by intense northeasterly winds. The Uruguayan coast constitutes the leading (poleward) edge of the distribution of E. brasiliensis, where climate change effects are projected to intensify. Extrapolation of these results to a climate change scenario with stronger La Niña events, suggest that larval transport to southernmost beaches will become more probable.