DOI: 10.17882/106872
title: Marseille bay Copepod Time series Dataset (2006-2020)

description: This series is part of the long-term planktonic monitoring of Marseille Oceanographic Laborarories (successively Centre Océanographique de Marseille, Laboratoire d’Océanographie Biologique, Laboratoire d’Océanographie Physique et Biogéochimique, and presently Mediterranean Institute of Oceanography / OSU Pytheas). It aims at describing the dynamics of the mesozooplankton community in term of abundance per taxonomic groups from binocular observation.
The zooplankton time series was initiated in 2002 by F. Carlotti and was linked with the on-going SOMLIT monitoring program. The sampling of zooplankton was carried out before 2012 mainly by F. Carlotti's students as part of their PhD or MSc work, V. Riandey, E. Dieval, A. Nowaczyk, K. Morsly, N. Neffati, A. Dron, S. Martini, then after 2012, mainly by L. Guilloux, sometimes supported by PhD students K. Donoso, G. Feliu, C-T Chen and T Garcia. Before 2005, sampling was not completely regular. 
The sampling is carried out twice a month at a fixed station in the center of the bay of Marseille (43.2417°N; 5.29167°E) with a depth of 60m (see  https://www.somlit.fr/marseille/). The WP2 net (200μm mesh) is hauled vertically+ from 55 m to the surface. Sample preserved in 4% buffered formalin and stored over the long term at the MIO. This dataset contains the planktonic organisms collected by a WP2 net (Diameter 55 cm; Length: 3 m; Mesh size: 200μm mesh) and therefore covering zooplanktonic organisms from 200µm to ~2cm. 
The observation protocol is the same for the whole series: Sample were rinsed to remove formaldehyde, and then separated into two size classes: 200-1000 µm and &gt; 1000 µm, with a 1000 µm sieve. Then, using a Motoda box, sub-samples were prepared to have around 500 organisms identified and counted for each size class.
Taxonomic identification was realized by the same expert, Loic Guilloux, IE, CNRS. The level of taxonomic determination may have changed with the acquisition of expertise over time. For this taxonomic identification and counting, samples were observed under binocular. Among the 86 taxa found, 94 were identified to family or higher level, 59 to genus and 113 to species. The taxonomic name refers to the WoRMS taxonomy. Species/genus identification was done according to Rose (1933), Tregouboff and Rose (1957), and Razouls et al. (2005–2017). Since 2017, these observations are carried out as part of the Microscopy and Imaging Platform (MIM) of MIO.
The data set is not fully continue over the time series period, and contains between 2 and 21 values per year for the year 2006, 2007, 2008, 2009, 2011, 2012, 2013, 2015, 2016, 2017, 2018, 2020, 2021 and 2022 (until September). The samples of years before 2016 were processed after 2017 on the archived samples.
The data collection and processing has been funded by several FC’s projects over its lifetime. 
 
The archive contains one excel file (2024.07.15_SOMLIT_comptages_ind_m3_FC2.xlsx), one comma separated values (2024.07.15_SOMLIT_comptages_ind_m3_FC2.csv) file with the same values as the excel one containing all data per taxa for the different dates between 2006 and 2022, and one text file (alphabeticalListOfTaxa.txt) with the alphabetical list of taxa .
The taxonomic name refers to the WoRMS taxonomy. Taxa are identified either to family or higher level (order, class) or to genus or to species                                                                       
For copepods, C1-C5 refers to undifferentiated copepodite stages between C1 and C5.                                     
For copepods, nauplii refers to undifferentiated naupliar stages.                                                             
For copepods, female or male denote a differentiation between sexes. No mention of sex means undifferentiated adults.                            
Taxa highlighted in blue: copepods                                                             
Taxa highlighted in orange: other organisms than copepods