The 200-mile fishing limit has changed fishing patterns and, in recent times, fishing boats are becoming more specialised and standardised. In the United States and Canada more use is made of large factory trawlers, while the huge blue water fleets operated by Japan and the Soviet-bloc countries have contracted. In western Europe, fishing vessel design is focused on compact boats with high catching power.
Commercial fishing is a high risk industry, and countries are introducing regulations governing the construction and operation of fishing vessels. The International Maritime Organization, convened in 1959 by the United Nations, is responsible for devising measures aimed at the prevention of accidents, including standards for ship design, construction, equipment, operation and manning.
According to the FAO, in 2004 the world's fishing fleet consisted of 4 million vessels. Of these, 1.3 million were decked vessels with enclosed areas. The rest were open vessels, of which two-thirds were traditional craft propelled by sails and oars. By contrast, nearly all decked vessels were mechanized. Of the decked vessels, 86 percent are found in Asia, 7.8 percent in Europe, 3.8 percent in North and Central America, 1.3 percent inAfrica, 0.6 percent in South America and 0.4 percent in Oceania. Most commercial fishing boats are small, usually less than than 30 metres (98 ft) but up to 100 metres (330 ft) for a large purse seiner or factory ship.
Commercial fishing vessels can be classified by architecture, the type of fish they catch, the fishing method used, or geographical origin. The following classification follows the who classify commercial fishing vessels by the gear they use.
Fishing gear
Drum winches mounted at the stern of an Irish trawler
Trawlers
Drawing of a trawler.gif
Drawing of a large trawler.gif
Main article: Fishing trawler
A trawler is a fishing vessel designed to use trawl nets in order to catch large volumes of fish.
* Outrigger trawlers - use outriggers to tow the trawl. These are commonly used to catch shrimp. One or two otter trawls can be towed from each side. Beam trawlers, employed in the North sea for catching flatfish, are another form of outrigger trawler. Medium sized and high powered vessels, these tow a beam trawl on each side at speeds up to 8 knots.
* Beam trawlers - use sturdy outrigger booms for towing a beam trawl, one warp on each side. Double-rig beam trawlers can tow a separate trawl on each side. Beam trawling is used in the flatfish and shrimp fisheries in the North Sea. They are medium sized and high powered vessels, towing gear at speeds up to 8 knots. To avoid the boat capsizing if the trawl snags on the sea floor, winch brakes can be installed, along with safety release systems in the boom stays. The engine power of bottom trawlers is also restricted to 2000 HP (1472 KW) for further safety.
* Otter trawlers - deploy one or more parallel trawls kept apart horizontally using otter boards. These trawls can be towed in midwater or along the bottom.
* Pair trawlers - are trawlers which operate together towing a single trawl. They keep the trawl open horizontally by keeping their distance when towing. Otter boards are not used.
* Side trawlers - have the trawl set over the side with the trawl warps passing through blocks which hang from two gallows, one forward and one aft. Until the late sixties, side trawlers were the most familiar vessel in the North Atlantic deep sea fisheries. They evolved over a longer period than other trawler types, but are now being replaced by stern trawlers.
Commercial fishing is a high risk industry, and countries are introducing regulations governing the construction and operation of fishing vessels. The International Maritime Organization, convened in 1959 by the United Nations, is responsible for devising measures aimed at the prevention of accidents, including standards for ship design, construction, equipment, operation and manning.
According to the FAO, in 2004 the world's fishing fleet consisted of 4 million vessels. Of these, 1.3 million were decked vessels with enclosed areas. The rest were open vessels, of which two-thirds were traditional craft propelled by sails and oars. By contrast, nearly all decked vessels were mechanized. Of the decked vessels, 86 percent are found in Asia, 7.8 percent in Europe, 3.8 percent in North and Central America, 1.3 percent inAfrica, 0.6 percent in South America and 0.4 percent in Oceania. Most commercial fishing boats are small, usually less than than 30 metres (98 ft) but up to 100 metres (330 ft) for a large purse seiner or factory ship.
Commercial fishing vessels can be classified by architecture, the type of fish they catch, the fishing method used, or geographical origin. The following classification follows the who classify commercial fishing vessels by the gear they use.
Fishing gear
Drum winches mounted at the stern of an Irish trawler
Trawlers
Drawing of a trawler.gif
Drawing of a large trawler.gif
Main article: Fishing trawler
A trawler is a fishing vessel designed to use trawl nets in order to catch large volumes of fish.
* Outrigger trawlers - use outriggers to tow the trawl. These are commonly used to catch shrimp. One or two otter trawls can be towed from each side. Beam trawlers, employed in the North sea for catching flatfish, are another form of outrigger trawler. Medium sized and high powered vessels, these tow a beam trawl on each side at speeds up to 8 knots.
* Beam trawlers - use sturdy outrigger booms for towing a beam trawl, one warp on each side. Double-rig beam trawlers can tow a separate trawl on each side. Beam trawling is used in the flatfish and shrimp fisheries in the North Sea. They are medium sized and high powered vessels, towing gear at speeds up to 8 knots. To avoid the boat capsizing if the trawl snags on the sea floor, winch brakes can be installed, along with safety release systems in the boom stays. The engine power of bottom trawlers is also restricted to 2000 HP (1472 KW) for further safety.
* Otter trawlers - deploy one or more parallel trawls kept apart horizontally using otter boards. These trawls can be towed in midwater or along the bottom.
* Pair trawlers - are trawlers which operate together towing a single trawl. They keep the trawl open horizontally by keeping their distance when towing. Otter boards are not used.
* Side trawlers - have the trawl set over the side with the trawl warps passing through blocks which hang from two gallows, one forward and one aft. Until the late sixties, side trawlers were the most familiar vessel in the North Atlantic deep sea fisheries. They evolved over a longer period than other trawler types, but are now being replaced by stern trawlers.
* Stern trawlers - have trawls which are deployed and retrieved from the stern. Larger stern trawlers often have a ramp, though pelagic and small stern trawlers are often designed without a ramp. Stern trawlers are designed to operate in most weather conditions. They can work alone when midwater or bottom trawling, or two can work together as as pair trawlers.
* Freezer trawlers - The majority of trawlers operating on high sea waters are freezer trawlers. They have facilities for preserving fish by freezing. They are medium to large size trawlers, with the same general arrangement as stern or side trawlers.
* Wet fish trawlers - are trawlers where the fish is kept in the hold in a fresh/wet condition. They must operate in areas not far distant from their landing place, and the fishing time of such vessels is limited.
http://www.runescape.com/kbase/guid/the_fishing_trawler
* Freezer trawlers - The majority of trawlers operating on high sea waters are freezer trawlers. They have facilities for preserving fish by freezing. They are medium to large size trawlers, with the same general arrangement as stern or side trawlers.
* Wet fish trawlers - are trawlers where the fish is kept in the hold in a fresh/wet condition. They must operate in areas not far distant from their landing place, and the fishing time of such vessels is limited.
http://www.runescape.com/kbase/guid/the_fishing_trawler
