Vertical and horizontal larval distribution of an offshore brachyuran crab, Monodaeus couchii, off the south coast of Portugal

Scientia Marina

Henrique Queiroga¹  Patricia N. Pochelon²  A. Miguel P. Santos³  Antonina dos Santos⁴ 

[1] CESAM, Departamento de Biologia, Campus Univeristario Santiago, Universidade de Aveiro;Instituto Português do Mar e da Atmosfera (IPMA) - CESAM, Departamento de Biologia, Campus Univeristario Santiago, Universidade de Aveiro;Instituto Português do Mar e da Atmosfera (IPMA) / CCMAR;Instituto Português do Mar e da Atmosfera (IPMA);

关键词: diel vertical migration;    crustacean;    deep sea;    invertebrate larva;    vertical distribution;    monodaeus couchii;    iberian peninsula;   

DOI  :  10.3989/scimar.03944.30F

来源: DOAJ

【 摘 要 】

A strong understanding of larval distribution and abundance is of major value in delineating the location and size of a breeding population of deep-sea species such as Monodaeus couchii. In this study, vertical distribution of the larvae of a brachyuran crab, M. couchii, was assessed during two week-long cruises conducted at the end of January 2006 and 2007 off the South Coast of Portugal. Larvae were collected by oblique plankton hauls with a Longhurst-Hardy Plankton Recorder from the surface to 300 m. Abundance and distribution of zoeae I and II were correlated during both years. For all stages, abundance decreased with depth during the day while it increased with depth at night; the larvae thus displayed reverse diel vertical migration. Abundance of zoeae I and II was correlated with chlorophyll a levels, whereas those of later stages were correlated with neither physical parameters (chlorophyll a, temperature or salinity) nor each other. An ontogenic shift in vertical distribution explained the results; earlier zoeal stages remain in the food-rich upper water column while later stages were not correlated with any physical parameters (i.e. chlorophyll a, salinity or temperature) and migrated to the bottom for settlement.

【 授权许可】

Unknown