Mesozooplankton sample data from R / V Pelican cruises PE 03-NGOMEX , PE 04-NGOMEX , PE 06-NGOMEX , PE 07-NGOMEX , PE 0905 in the Northern Gulf of Mexico from 2003-2008

CTD casts using a high-capacity, diaphragm pump were conducted during the R/V Pelican cruises PE03-NGOMEX, PE04-NGOMEX, PE06-NGOMEX, PE07-NGOMEX, and PE09-05 in the Northern Gulf of Mexico between 2003 and 2008. Plankton samples were collected from discrete depths during the CTD casts. Subsamples of sample contents were manually counted, identified, and measured in the laboratory. For a complete list of measurements, refer to the supplemental document 'Field_names.pdf', and a full dataset description is included in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: http://www.bco-dmo.org/dataset/746107

supplemental document 'Field_names.pdf',and a full dataset description is included in the supplemental file 'Dataset_description.pdf'.The most current version of this dataset is available at: http://www.bco-dmo.org/dataset/746107

Dataset Description
Subsets of these data were published in the papers listed in the "Related Resources" section.

Methodology:
Plankton samples were collected from discrete depths during CTD casts using a highcapacity, diaphragm pump with an intake hose mounted to the CTD Rosette.Subsamples of sample contents were manually counted, identified, and measured in the laboratory Sampling and analytical procedures: For each sample, the pump was run for a timed period of nominally 5 min.The flow rate of the pump was usually measured immediately prior to sampling, by recording the time required to fill a barrel of known volume.Samples were preserved and stored in 5% buffered formalin.
The laboratory protocol was to separate samples into two size fractions by passing them through large (200 or 500 μm) then small (64 μm) mesh sieves; split, dilute, and sub-sample each size fraction as needed; count and identify all plankters (minimum n = 50) in each subsample; and estimate the length and width of exactly 100 plankters (the first 50 from the large and small fraction, respectively) to the nearest 50 μm using a dissecting microscope.
Three replicate small size fractions per sample were processed starting in 2006.Nominal sampling time and depth were corrected by analysis of CTD upcast data.CTD pressure sensor measurements at depth were adjusted to compensate for non-zero readings on deck of the research vessel over the course of each cruise.Bottom depth was estimated from filtered CTD altimeter and pressure data.Longitude and latitude were taken from the vessel's MIDAS system or a separate GPS unit at the time the CTD was turned on.
Inconsistent taxonomic identifications (e.g., misspelled or misleading colloquial categories) were corrected by manually creating and automatically applying a lookup table.All data processing was performed using the R language and environment for statistical computing.

BCO-DMO
Data column "vol" was calculated as follows: vol = length(unique(replicate)*aliquot/beaker/2^splits*50/s_per_50l*d_min*60*1e-3 Data column "flag" contains the following codes: flag 1: length & width were not measured, but estimated from similar samples flag 2: shallow & deep samples not labeled, but deduced from sample contents flag 3: depth estimate less accurate than usual (± ~3 m) flag 4: time estimate less accurate than usual (± ~15 min) flag 5: pump flow rate estimated by nominal flow rate Processing Description Data processing: Temperature, Depth (CTD)  unit is an integrated instrument package designed to measure the conductivity, temperature, and pressure (depth) of the water column.The instrument is lowered via cable through the water column and permits scientists observe the physical properties in real time Instrument Description via a conducting cable connecting the CTD to a deck unit and computer on the ship.The CTD is often configured with additional optional sensors including fluorometers, transmissometers and/or radiometers.It is often combined with a Rosette of water sampling bottles (e.g.Niskin, GO-FLO) for collecting discrete water samples during the cast.This instrument designation is used when specific make and model are not known.a device that moves fluids (liquids or gases), or sometimes slurries, by mechanical action.Pumps can be classified into three major groups according to the method they use to move the fluid: direct lift, displacement, and gravity pumps [ Data Manager Processing Notes: table of contents | back to top ] Description 2007 Sampling cruise to the Northern Gulf of MexicoNote: Deployment Id and Chief Scientist assigned by BCO-DMO staff (not official) Websitehttps://www.bco-dmo.org/deployment/581212008 Sampling cruise to the Northern Gulf of MexicoNote: Cruise ID confirmed with R2R catalog Original cruise data are available from the NSF R2R data