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Zooplankton
Zooplankton
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CalCOFI Zooplankton data are available through NOAA IchthyoDB, SIO DataZoo, and the Cooperative Zooplankton DataspaceNOAA Technical Memorandum which describes At Sea Methods and Lab Procedures. |
IchthyoDB is a queriable database of egg and larval counts from CalCOFI net tow samples that have been sorted by personnel at the Southwest
Fisheries Science Center. This database spans from 1950 to present.
- Header Definitions and query filter filter suggestions from the Ichthyo-Database are described on the NOAA Website.
- At Sea Methods and Lab Procedures are described in a 1999 NOAA Technical Memorandum.
- Nets Deployed on CalCOFI cruises are described on an informational webpage on the CalCOFI website with links to NOAA Fisheries.
DataZoo, through Ocean Informatics, provides a web-based interface to a database storing multidisciplinary data, metadata, and study information.
- Fish Egg and Larvae Volumes - Vertical Tows: Counts of 17 species of ichthyoplankton for CalCOFI crusies. Contains data from vertical (CalVET and PairoVET) tows.
- Fish Egg and Larvae Volumes - Manta Tows: Zooplankton counts and volume from net tows for fish, sardine, and anchovy eggs and larvae. Contains data for Manta tows.
- Fish Egg and Larvae Volumes - Oblique Tows: Zooplankton counts and volumes from net tows for fish, anchovy, and sardine eggs and larvae. Contains data for starboard oblique tows (CALBOBL and CAL1MOBL).
Cooperative Zooplankton Dataspace; Mark Ohman Lab, Scripps Institution of Oceanography provides a web portal in which several databases
are made available to query and or plot from net tow samples collected by NOAA Fisheries on CalCOFI cruises.
- SIO Pelagic Invertebrates Collection. Searchable datbase of the SIO Pelagic Invertebrates Collection.
- ZooDB - Zooplankton Database - A queriable interface to extensive zooplankton data from the California Current System, 1951 through present.
- Brinton Euphausiid Plot Gallery - Geographical distributions of selected species, illustrated by Dr. Edward Brinton.
- BTEDB - Brinton and Townsend Euphausiid Database - A queriable interface to extensive euphausiid data, 1951 through present.
- MEDB - Marinovic Euphausiid Database - queriable interface to extensive euphausiid data, 2001 through 2007, from the central sector of the California Current System.
- CEQuI - A comprehensive euphausiid data module which provides an interface that queries across the Brinton and Townsend Euphausiid database and the Marinovic Euphausiid Database.
NOAA Fisheries Nets and Tow Techniques (photo gallery)
- Bongo or CalBOBL Net - two circles, 0.71 m in diameter, with a central yoke which connects to the towing cable. The nets are 3 m in length, a 1.5 m cylindrical portion joined to 1.5 m conical portion tapering to a detachable cod end. At least one (starboard net), the principal ichthyoplankton sample net, is made from 0.505 mm square mesh nylon. The sample from the port side net is used for other purposes; the mesh size is either 0.505 mm or 0.333 mm depending on requirements. The cod end of each net is constructed of 0.333 mm mesh. The ratio of mesh aperture area to mouth area is 4.8:1 for the 0.505 mesh net.
Plankton samples are obtained by retrieving the sampler at an oblique angle. A 22 kg weight is attached to the bottom of yoke frame. While the survey ship is making 1-2 knots, a fixed amount of towing cable is paid out, the net is held at depth for 30 seconds and then retrieved at a constant rate (20 m/min). Ship speed is adjusted to maintain the towing cable at a constant angle to the vertical ( 45 degrees +/- 3 degrees). During each plankton tow 300 m of towing cable is paid out; thus the vertical depth sampled is approximately 210 m. In shallow areas the amount of towing cable paid out is adjusted so that the net fished to approximately 15 m off the bottom.
- Pairovet or CalVET- 0.25 m in diameter pair; the nets are 1.5 m in length, a 0.8 m cylindrical portion joined to 0.6 m conical portion tapering to a 0.1 m cod end.
- 1980 - 1982: net was 0.333 mm square mesh nylon;
- 1983 - 1985: net was 0.150 mm square mesh nylon.
The ratio of mesh aperture area to mouth area is about 8:1.
Egg samples are obtained by vertically retrieving the net. A 45 kg weight is attached to the end of the towing cable, a few meters below the sampler. With the survey ship holding a stationary position, 70 m of towing cable was paid out, the net was held at depth for 10 seconds and then retrieved vertically at a rate of 70 m/min. The angle of stray from the vertical was not allowed to exceed 15 degrees
- MANTA -The twin winged continuous-flow surface tow, is used for samples on the ocean surface minimizing wake disturbance from the ship. The MANTA Net is an improved design from the Neuston Net and is capable of continuous-flow collection of organisms at the ocean surface. The frame is supported at the ocean surface by a pair of aquaplanes projecting at right angles from the paravanes. The net is towed by a wire yoke with one short bridle and one long bridle in order to angle the net from the ship. The net is nylon, nominally .505 mm square mesh with a 333 codend.
- Other Nets:
- CAL1MOBL - standard CALCOFI plankton sampler from 1951 through 1978.
1-meter in diameter, net (approximately 4 m) was attached. - MOCNESS - is used for specialized tows for zooplankton. The MOCNESS or Multiple Opening/Closing Net and Environmental Sensing System is based on the Tucker Trawl principle and is manufactured by Biological Environmental Sampling Systems (B.E.S.S.). M1 is a 1 meter frame with 10 nets. M2 is a 10 meter frame with six nets.
- CAL1MOBL - standard CALCOFI plankton sampler from 1951 through 1978.




