Fishing Craft Technology

Unit 1 - History and development of fishing craft

1.3. Classification of fishing craft
The fishing crafts can be classified into various types based on different criteria like, depth of operation, duration of voyage, size of vessel , materials used in the construction, type of propelling system and in accordance with the actual operation.

a) Based on depth of operation:

• Inshore vessels – Vessels operating up to 10 fathoms depth
• Offshore vessels – Vessels operating in the depth range of 10-40 fathoms
• Deep sea vessels – Vessels operating beyond 40 fathoms depth

b) Size of the vessel and duration of voyage:

• Near water – Vessels of length up to 12 m which makes daily trips or trips of short duration
• Middle water–Vessels of length between 12 and 30 m having and endurance of 7 days or more but not exceeding 25 days.
• Distant water – Vessels of size over 30 m length with endurance exceeding 25 days

c) Construction of hull:

• Decked boats
• Half decked boats
• Open boats

d) Materials used for construction:

• Wooden
• Steel
• Fibre glass reinforced plastic
• Ferro- cement
• Aluminum
• Composite

e) Based on Gross – Registered Tonnage:

• 1-25 GRT
• 26-50 GRT
• 51-100 GRT
• 101-250 GRT
• 251 – 500 GRT
• 501-1000 GRT

f) Area of operation of the vessel:

• Large vessels – Operating principally in open sea.
• Medium vessels – Operating in the EEZ marine areas.
• Small vessels – Predominantly used in coastal and sheltered marine and brackish water.

g) Based on their function:

1) Trawlers – Vessels which use trawl as fishing gear

• Side trawlers – Trawler in which the trawl is set over the side and the warps pass through blocks hanging from two gallows, one forward and one aft.
• Stern trawler – In a stern trawler, the gear is set and hauled over the stern. The warps are led from the trawl winch through various lead blocks over the stern.
• Wet – fish trawler – The fish is kept in the hold in the fresh/wet condition in a wet fish trawler
• Freezer trawler – A trawler which is equipped with refrigerating plant and freezing equipment and in which fish is preserved by freezing.
• Factory trawler – A trawler equipped with processing plants including mechanical gutting and filtering equipment with freezing installation, fish oil, fish-meals and some time canning plants. The number of crew in such a vessel is large.
• Out rigger trawler – These make use of out rigger booms to tow the gear.

2) Seines:

The vessels using surrounding gear and seine nets. Because of the high maneuverability required for the operation of these gears, normally seiners are provided with lateral thrusters.

• Purse–Seiners: Vessels which operate purse seine and which are equipped with pursing gallows and pursing winches for hauling of purse lines.Based on deck arrangement, purse seiners are differentiated intoNorth – American type: Bridge and accommodation located forward

European type: Bridge and accommodation is located aft. Net is mostly carried on the upper deck.

Tuna purse–seiners: Arrangement similar to North American type. They are normally equipped with a skiff.

• Seine netters : These vessels operate seiners which are surrounding nets attached to very long ropes.

Dredgers: Vessels which are use dredges for collecting molluscs from the bottom. The vessel should have sufficient power to drag the gear.

Lift netters: These vessels operate large lift nets which are raised and lowered by means of out riggers.

Gill netters: Gill nets are operated either set or drift and the larger vessels are often equipped with net haulers or net drums.

Trap setters: This includes vessels not only setting traps and pots but also pound nets, fyke nets, stow nets and various kinds of barriers.

3) Pot vessels:

• These set the pots for catching lobsters, crabs, cray fish and other similar species.
  

4) Liners:

• These vessels use lines and hooks with or without bait or lure.

• Hand liners: Hand lines are operated from small boats without any special features for gear handling.
• Long liners: The length of these vessels depends upon the length of long line to be set.
• Tuna long line: These are generally medium sized vessels. Brine freezing tanks for preservation of tunas are normally provided on these vessels.
  

5) Pole and line vessels:

• These vessels are provided with special platforms on the sides on which the fishermen stand. Tanks with live bait and a water spray system for fish attraction are typical features of these vessels.
• Japanese type pole and line vessel: In this the platform is on the forward part of the vessel and the bridge is at the aft.
• American type pole and line vessel: In these the platforms are located at the aft.
  

6)Trollers:

• Equipped with troll lines fitted with lures. These are attached to trolling booms which are raised and lowered by topping lifts.
  

7)Vessels using pumps for fishing:

• These are provided with pumps of special type which are lowered under the surface of water.
  

8) Multipurpose vessels:

• These are vessels which are equipped for alternative use of two or more different fishing gear without major modifications to the vessel outfit and equipment.

h) Non fishing vessel:

• Mother ships: The term is used for vessels which provide fishing vessel at sea with supplies of fuel, provisions, fresh water and other consumable goods, transfer the catch from the vessels, process and preserve them fresh, render medical and social services to the crew. They also transport and land fish products in port. They also carry on board small fishing vessels which are launched on arrival at the fishing ground. The catch is transferred to the mother ship for processing and preserving.
• Salted fish mother ships: The wet fish are salted, cured and put into barrels on these vessels. These are then stored in dry or refrigerated holds, depending upon the degree of salting.
• Factory mother ships: In this, fresh fish transferred at sea from fishing vessels undergoes processing and preserving operations similar to those provided on factory trawlers.
• Mother ships with catching vessels aboard: These carry small tuna long liners on board. The catcher vessels are carried on the upper deck and they are lowered and raised by means of booms and derricks.
• Mother ships for two boat purse-seining: These carry small tuna long liners on board. The catcher vessels are carried on the upper deck and they are lowered and raised by means of booms and derricks.
• Mother ships for two–boat purse–seining: These vessels carry two purse- seiners at the aft part of the vessel. The purse seiners set and haul the gear. Subsequently, the mother ships come along side and the fish is brailed or pumped into the mother ship.
• Fish carriers: These are used for transporting fish in refrigerated holds.
• Hospital ships: These render medical services to the crew of fishing vessels operating offshore
• Fishery protection vessels: They perform the function of protection of the fishing grounds and surveillance of fishing vessels operating in a country’s territorial waters and in the EEZ area.
• Fishery research vessels: These are engaged in fish stock assessment, experimental fishing using various gear and in fish handling/storage experiments.
• Fishery training vessels: These are used for training future fishermen in navigating, seaman ship, fishing operations and fish handling.