Zooplankton and Ichthyoplankton of the North Western Portuguese Coast in May 2002

The objective of this data collection was to analyze the daily vertical migration of decapods larvae in the water column in the northwestern Portuguese coast and to assess its correlations with environmental parameters. In order to do this plankton samples were collected with Bongo nets, LHPR multi-sampler and Neuston net in an area between the north western Portuguese coast and the 10° W and between the 40° and 42° N and, additionally at a fixed location during a 67 hours period, every two hours. In the fixed sampling point a plankton trap was also deployed. The data set presented corresponds to the zooplankton analyzed in all the samples taken. This work is part of the ProRecruit project, which aimed to describe the spatial and temporal variability of the recruitment of coastal invertebrate species that show a planktonic larval phase in their lifecycle, and understand the impact of environmental variables which may control its supply to the coastal systems.

From the analysis of the results, it has been concluded that decapods larvae perform vertical daily migrations from the layers near the bottom to the neuston layer, being present in the superficial layers from 10PM to 02AM and that this behavior enhances their retention in the area together with the upwelling season. On the other hand, the cypris larval phase of Cirripedia was shown to perform vertical migrations and that have occurred in more abundance between 20 m and 35 m of depth.