SCM 330 Ocean Discovery through Technology Area F GE

Sensors - Biological Traditional Approach Nets Bottles Sensors Fluorometers Optical Scattering (particle size) Flow Cytometers Acoustics VPR Light Sheets Molecular Tagging Theory Application Sensor

Video Plankton Recorders (Optical Plankton Recorders) The VPR is a video-microscope system used for imaging plankton and other particulate matter in the size range from a few micrometers to several centimeters.

The housing for a Video Plankton Recorder, with a very streamline shape, sits ready for deployment off the back of a research vessel.

A Video Plankton Recorder's instruments are given a check before use.

Optical plankton (or particle) counters work in a similar way to Video Plankton Recorders (VPRs), allowing a stream of ocean water to pass by a recording device that can count the number of plankton-sized particles in the water. When calibrated with the speed of the vessel towing the OPC, scientists can calculate the amount of water sampled to determine the number of organisms per volume of ocean water. In addition to counting the number of particles of different sizes, laser OPCs can record an image of the silhouette of particles passing through it, allowing for species identification of certain larger planktonic organisms such as krill and large copepods. Like VPRs, OPCs are generally housed inside a towed vehicle such as the Moving Vessel Profiler (MVP) or attached to trawls, etc., to allow for a more thorough investigation of the marine environment.

Laser Optical Counter (LOPC) Zooplankton distributions relative to physical features

Data collected during a 24 hour test deployment of the moored OPC in Emerald Basin in September Data were collected at 30 minute intervals. Histogram bars indicate counts of Calanus finmarchicus copepodite stages IV and V grouped.

LOPC specifics Size range: 100  m-20 mm Counting rate: 200 s -1

ECOshuttle LOPC ECOshuttle-LOPC Can also be attached with nets

CTD+OPC data coverage

Line Zooplankton (x10 4 #/m 3 )

Line 2 Zooplankton (x10 4 #/m 3 )

Line 3 Zooplankton (x10 4 #/m 3 )

Line 4

Line 5 Zooplankton (x10 4 #/m 3 )

A diagram of an Optical Plankton Recorder, showing the beam of light (in red) that shines across the path of water flowing through the center of the instrument, recording a simple image of any plankton in that water.

Underwater Video Profiler (UVP) The UVP uses high-resolution cameras and a powerful lighting system to record video of zooplankton and large phytoplankton as it passes through the water column. In addition to plankton, this instrument can study suspended particles and environmental conditions associated with the observed organisms. UVPs are lowered from a research vessel that has instrumentation on board to view the images being generated. The profiler's images are not quantitative like those from an Optical Plankton Counter, but this technology does provide a useful catalog of organisms found at different depths at a given research site. The profiler can generate spectacular images similar to those from a Remotely-Operated Vehicle or manned submersible, but at much less effort and expense.