Characteristics of Red Sea fisheries
Purse seine fishery in the Red Sea:-
Purse seine is one of the most important fishing gears in the Red Sea fishery of Egypt. A purse seine is made of a long wall of netting frame with float line and lead line usually, of equal or longer length than the former and having purse rings handing from the lower edge of the gear, through which runs a purse line made from steel wire or rope which allow the pursing of the net. For most of the situation, it is the most efficient gear for catching large and small pelagic species that is shallow (FAO,2013). purse seine is a preferred technique for capturing fish species which aggregate, close to the surface: such a sardine, mackerel, anchovies, herring, certain species of tuna and others. There is impact on the bottom habitat except when the water depth is less than height of purse seine during the fishing operations and that the lower edge of the gear wipes the sea bottom (FAO, 2013). However purse seine fishing can have negative impacts on fish stocks because it can involve the by catch of non-target species and it can put too much pressure on fish stocks. More than 46% of the total Egyptian Red Sea catch is taken from the purse seine fishery, and more than 87% of the total purse seine fishery catch are around scad, sardinella and anchovy.
Trawl fishery in the Red Sea:-
Trawl systems are playing very important role in commercial fishery and in resources survey. The trawl consists of the warp, otter boards, ropes and trawl net. The mid-water trawl system on a commercial fishing vessel can be managed efficiently by crew (Park, 2007). Trawl nets that are towed behind a boat to collect organisms have been used by fisheries for centuries. Trawls can be divided into three categories based on where they sample the water column: surface, midwater, and the bottom. More than 24% of total Egyptian Red Sea catch is taken from the trawl fishery, and more than 62% of total trawl fishery catch are brush tooth lizardfish and trieadin breams (GAFRD, 2011).
Longline fishery in the Red Sea:-
Longline fisheries are a commercial fishing technique. It uses a long line, called the main line, with baited hooks attached at intervals by means of branch lines called Snoods or Gangions (Method and Apparatus, 2008). A snood is a short length of line, attached to the main line using a clip or swivel, with the hook at the other end. Longlines are classified mainly by where they are placed in the water column. This can be at the surface or at the bottom. Lines can also be set by means of an anchor, or left to drift. Hundreds or even thousands of baited hooks can hang from a single line. In some unstable fisheries, such as the Patagonian Tooth fish, fishermen may be limited to as few as 25 hooks per line. In contrast, commercial longliners in certain robust fisheries of the Bering Sea and North Pacific generally run over 2.500 hand-baited hooks on a single series of connected lines many miles in length (Rice et al., 2006). More than 16% of total Egyptian Red Sea catch is taken from the longline fishery, and more than 79% of total longline fishery catch are groupers and emperors or scavengers (GAFRD, 2011).
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