Comprehension of spatial distribution and structure of marine population is a key tool to optimize the design of marine protected areas. Marine populations are usually structured as metapopulation. The connection between sub-populations depends on the exchanges of individuals, and dispersal is an important notion in population connectivity. As many organisms are sessile, a significant source of dispersal is the larval dispersal. The pelagic larval duration (PLD) varies over a broad range from hours to months. During this time larvae are transported and influenced by oceanographic features. The aim of this project is to study the impact of directionally biased dispersal, due to current, on persistence of marine organisms and further on the design of marine protected areas. One of the common assumptions is that asymmetry will increase with the PLD and that longer PLD will lead to greater dispersal distance. Our results, obtained with different models, showed that dispersal distance is not increased, nor the asymmetry when PLD is increased, in eddies formation areas. In most of the cases persistence is overestimated in symmetrical dispersal compared to asymmetrical dispersal (due to the importance of connectivity on persistence). However in some cases (large network of reserves) current has a beneficial impact on persistence due to increased connections among the reserves. Our results also present insight for dispersal pattern in eddy formation areas.
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