FOCI Standard Operating Instructions
January 2002
3.2.8 Midwater Trawls - Marinovich, Rope, or Stauffer midwater
trawls may be requested for collecting fish. Midwater trawls will
be deployed using standard shipboard procedures. The Chief Scientist
or Watch Chief will decide trawl locations, times and depths. Midwater
trawls will be conducted day or night, and may depend upon the results
of other sampling, such as plankton catches or acoustic sign seen on the
SIMRAD EK500 Scientific Echosounder. When requested, the ship’s crew
will need to be activated quickly, with little time lost. Aside from orders
relayed from a scientist, deployment and retrieval of each trawl is the
responsibility of the ship’s crew. A Furuno wireless netsonde for
real-time monitoring of the headrope height is provided by the ship and
usually mounted on the center of the headrope. A Sea-Bird Electronics
SBE 39, provided by the scientists, is mounted alongside the netsonde to
provide a record of time, net depth, and ambient temperature.
allen.macklin@noaa.gov