When fishermen throughout India pull up a
trawl net, about 15-20 % of what they get is considered "bycatch" -- less valuable species they weren't looking for, according to CMFRI principal scientist Shyam Salim, who has studied climate change and vulnerability in India's coastal communities.
The
trawl net was an Aberdeen-type bottom trawl (NET Systems, Inc., Bainbridge Island, WA) with a 14.0-cm (5.5-in) stretch mesh and 3.8-cm (1.5-in) mesh liner that extended from the middle of the intermediate section to the codend.
As 15th April to 30th May being closed season for
trawl net along the coast of Tamil Nadu, One of the peak seasons has been recorded as March instead of May.
A General Oceanics flowmeter (General Oceanics, Miami, Florida), suspended inside the zooplankton net, was set at the start of zooplankton collection and net trawling, and then read when the zooplankton net and
trawl net reached the boat to estimate water flow through the zooplankton net and
trawl net.
This study measured the amount of time it took bottlenose dolphins (Tursiops truncatus) to arrive near a shrimp trawl vessel whether or not a
trawl net was deployed and the amount of time after a
trawl net was deployed before dolphins engaged in foraging from the
trawl net.
What name is given to the device which keeps the mouth of a
trawl net open?
The calculation of the fictitious area of the nets (At) showed that the semi-balloon
trawl net had a greater area (147.13 [m.sup.2]) than that of the Korean
trawl net (75.44 [m.sup.2]).
Southern California Trawlers Association members have continuously refined the halibut
trawl net to minimize by catch and any other potential effects on marine ecosystems.
1) and collected the scallops with a bottom
trawl net (mouth opening width, 2.4 m; mesh opening size, 90 mm) along the bottom for 200 m at each station in mid October between 2007 and 2010.
Using a standard plankton
trawl net with a sieve of 300 microns modified for the voyage, the crew regularly skimmed the surface for tiny, insidious fragments of plastic and had a 100 per cent recovery rate.
O'Neill, "Differential equations governing the geometry of a diamond mesh cod-end of a
trawl net," Journal of Applied Mechanics, Transactions ASME, vol.
* Manjubeira:
trawl net used in the water column, which presents bridle lines in its arms in order to keep it open, attached to cables that serve to tow it towards the river bank.