ICES Journal of Marine Science: Journal du Conseil Advance Access published online on June 16, 2008
ICES Journal of Marine Science: Journal du Conseil, doi:10.1093/icesjms/fsn093
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Dispersal of Munida gregaria (Decapoda: Galatheidae) larvae in Patagonian channels of southern Chile
1 Programa de Magíster en Ciencias con mención de Zoología, Departamento de Zoología, Universidad de Concepción, Concepción, Chile
2 Laboratorio de Oceanografía Pesquera y Ecología Larval (LOPEL), Departamento de Oceanografía and Centro FONDAP-COPAS, Universidad de Concepción, Concepción, Chile
3 Facultad de Ciencias del Mar, Universidad de Valparaíso, Av. Borgoño 16344, Valparaíso, Chile
Correspondence to R. León: tel: +56 41 220 4152; fax: +56 41 223 8982; e-mail: rleonl{at}udec.cl
León, R., Castro, L. R., and Cáceres, M. 2008. Dispersal of Munida gregaria (Decapoda: Galatheidae) larvae in Patagonian channels of southern Chile. – ICES Journal of Marine Science, 65.The dispersal of Munida gregaria larvae in Chilean Patagonian channels was assessed in spring 2002 and 2003, and winter 2003. In winter 2003, zoea I was the most abundant stage in all channels and there were no larval stages older than zoea IV. In spring 2002 and 2003, there were six larval stages in all channels, and the greater abundance of older larvae suggested that reproduction takes place in winter and larval development in spring. Further, analysis of spatial distribution by stage revealed that early zoeae moved seawards. Generalized Additive Models analyses showed that most larval stages were temperature-dependent, and that the salinity range of the youngest zoea was wider than that of older larvae and post-larvae, coinciding with an ontogenetic distribution change from estuary to shelf. Residual flows determined with an acoustic Doppler current profiler revealed two layers of opposite flow: the shallowest layer moved seawards and the deeper layer onshore. The surface layer was wider in spring than in winter because of seasonal increase in fresh-water input. The dispersal pattern of M. gregaria consisted of an inner channel larval release in winter, followed by an along-channel larval drift and subsequent export to the shelf in spring. The mechanism by which juveniles return to the channels seemed to be associated with the onshore subsurface flow.
Keywords: export strategy, larval distribution, Magellan Province, Patagonian fjords, squat lobster
Received 23 June 2007; accepted 25 March 2008.