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7885503 
Journal Article 
The importance of retention zones in the dispersal of larvae 
Largier, J 
2004 
Yes 
American Fisheries Society. Symposium
ISSN: 0892-2284 
AMERICAN FISHERIES SOCIETY SYMPOSIUM 
42 
105-122 
WOS:000223814600012 
Dispersal of young life stages is often the predominant connection between spatially separated populations. Thus, one can expect that dispersal plays a critical role in determining the effectiveness of aquatic protected areas as fishery management tools. This piece focuses on two primary aspects of dispersal that result in dispersal not being a simple product of mean flow and time in the plankton: flow features (retention) and behavior (swimming). Recently, increasing attention is being given to retention zones-regions where currents act to retain propagules (regions with limited exchange with surrounding waters). Both observations and models of meroplankton and of recruitment suggest the importance of retention zones in population dynamics and that these may be good sites for aquatic protected areas. Retention zones may occur in a variety of environments, each exhibiting specific circulation patterns, time scales, and opportunities for import or export. In addition, each type of retention zone offers a different habitat type and different exposure to external influences. The value of these retention zones to fisheries depends on the population of interest and the time scale, size, location, and "retentiveness" of the retention zone. Typically, retention zones are not "closed"-they are not isolated from the main flow. Nonzero exchange between retention zones and surrounding waters is critical for both dispersal of propagules and the nature of the habitat. Swimming can have a large influence on retention processes and how retention zones are used by early life stages. Even very weak behavior can exert control on export or import rates and timing. Age-specific behavior may be critical to populations using these retention zones to enhance local recruitment and spillover effects at the same time. 
Shipley, J. B.