How larval traits of six flatfish species impact connectivity

Abstract

Connectivity and dispersal are important factors for ecosystem dynamics, conservation, and resource management. Dispersal and recruitment success are determined in early life for many marine species. For those larvae that are pelagic, transport from spawning to nursery grounds is driven by hydrodynamic processes. Other environmental factors such as temperature and biological factors such as ecophysiology, behavior, and reproductive strategy (spawning period and spawning grounds) influence the final dispersal pattern and larval survival. We utilized a Lagrangian particle tracking model coupled with a three-dimensional hydrodynamic model (Larvae&Co) to assess the connectivity patterns between spawning and nursery grounds of six commercially exploited flatfish species in the North Sea over a 10-yr period (1997)(1998)(1999)(2000)(2001)(2002)(2003)(2004)(2005)(2006). Standardized analyses have highlighted how spawning and nursery grounds are connected under the combined pressure of environment and life-history traits. Results showed that the six flatfishes can be divided in two groups, each with their specific connectivity patterns. Turbot, common sole, and brill live in two subpopulations in the North Sea; common dab, European flounder, and European plaice represent a single mixed population. In general, the modeled and genetic patterns match, hence showing the strong impact of larval connectivity. The large overlap in connectivity for species that spawn during the same period and the seasonal change in hydrodynamics highlight the strong impact of a summer front in larval dispersal. Our results prove that individual-based modeling is a powerful tool to guide resource management, even in cases of limited biological information.

Fine‐scale seascape genomics of an exploited marine species, the common cockle Cerastoderma edule, using a multimodelling approach

“…Geographic proximity certainly favours gene flow, but oceanographic currents aiding larval transport are also major drivers of population structure (Barbut et al, 2019 gene flow between these populations is low, seemingly contradicting the larval transport model's prediction of high connectiv-…”

Population genetic structure of turbot (Scophthalmus maximus L., 1758) in the Black Sea

“…S. maximus produce pelagic eggs. The mean larval duration of turbot is estimated as 44.7 ± 5.3 days and the mean dispersal range during the pelagic stage was estimated as 102 ± 9 km in the Baltic Sea (Barbut et al ., 2019). Compared to other flatfish species, turbot shows an intermediate dispersal capacity.…”

“…S. maximus produce pelagic eggs. The mean larval duration of turbot is estimated as 44.7 ± 5.3 days and the mean dispersal range during the pelagic stage was estimated as 102 ± 9 km in the Baltic Sea (Barbut et al, 2019). recently evaluated with a limited number of specimens using microsatellite and mtDNA markers, and genetic differences were found between sampling sites (Turan et al, 2019b).…”

The hemoglobin Gly16β1Asp polymorphism in turbot (Scophthalmus maximus) is differentially distributed across European populations

“…However, interspecific differences have been found in the tolerance to high temperatures and hypoxic conditions that seem to be associated with differences in gill ventilation, oxygen uptake, and functional properties of hemoglobins (Weber and de Wilde 1975 , 1976 ; Steffensen et al 1982 ; van den Thillart et al 1994 ; Taylor et al 2007 ). Moreover, larval dispersal and connectivity among populations were recently shown to vary among six flatfish species in the Northeast Atlantic Ocean (Barbut et al 2019 ), and local adaptation and genetic divergence between populations have consistently been reported in several species, including common sole ( Solea solea ) (Diopere et al 2018 ), European flounder ( Platichthys flesus ) (Hemmer-Hansen et al 2007 ; Pédron et al 2017 ), and turbot ( Scopthalmus maximus ) (Vandamme et al 2014 ; Vilas et al 2015 ; do Prado et al 2018a ).…”