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Fishing traps and hooks

  1. Fishing gear (traps, hooks and lines, spears etc.
  2. Traps are fishing devices into which fish or shellfish are enticed by bait or shelter spaces or enclosures where they are guided to enter, because of an obstacle placed in their normal migration path and from which their escape is made difficult by constriction, retarding valves or labyrinths. Trap fishing is a passive fishing technique of ancient origin. There is extraordinary variety in their design, fabrication and operation. Fish Traps
  3. Traps of Bangladesh Generally, there are 26 types of traps are seen in Bangladesh. • Ahuka • Anta • Benki • Bhair • Chak jal • Charo • Chata • Chouka • Chunga • Darki • Dhair • Dhak • Doar • Guchi • Ichha chai • Jhalanga • Jhurka • Katya • Kholson • Paor • Paron • Polo • Shinghi chai • Shol chai • Thui • Thusi
  4. The diagram shows barramundi being guided to the mouth of the fish trap by the fences
  5. Advantages of trap fishing • High species and size selectivity • High potential for survival of discarded non- target species • Low energy requirement in operation • Low environmental impacts during operation • Excellent condition of the catch which are usually alive when caught • High market value of the catch • Traps can be made from locally available materials
  6. Disadvantages of trap fishing • Traps are usually bulky and occupy considerable space on board and are relatively difficult to operate and haul during rough weather • High loss rate during operation • Ghost fishing by lost traps leading to unwanted fishing mortality
  7. Line fishing Fishing by means of hand or long lines with baited hooks is known as line fishing. A fishing line is a cord used or made for angling. Important parameters of a fishing line are its length, material and weight. Principles of line fishing: Fish are attracted by a natural/artificial bait (lure) placed on a hook fixed to the end of a line on which they may get caught/hooked. When fish swallow the bait including the hook then after dragging the hook it is attached with the jaw of the fish.
  8. Materials of hook • Hook is made of metal • Usually steel is used • Iron and copper is also used Structure of a hook • Eye • Shank • Bend • Point • Barb
  9. Types of line fishing 1. Hand line 2. Short line 3. Long line 1. Hand line Usually hand line is used for catching small amount of fish.  Structure (hook and fishing rod)  Mode of operation  Where placed
  10. 2. Short line (20-30 m))  Structure (strong cord, snood with hooks, float)  Mode of operation  Where placed 3. Long line (50-100 m)  Structure (strong cord, snood with hooks, float)  Mode of operation  Where placed
  11. Classification of line fishing on the basis of mode of placing 1. Floating line 2. Hand line 3. Drift line 4. Trawl line 5. Set line
  12. 1. Floating line • Used for catching surface water fish • Float is used for placing line • Boat or bamboo pole may be used • Nylon cord is used Catchable species Wallago attu, Bagarius bagarius, Silonia silondia, Pangasius pangasius, Channa straitus, Mystus aor, Channa marulius, etc.
  13. 2. Hand line This line is usually operated by hand. a) Hand line without wheel When fish get stuck with the hook it is pulled on by hand. Mainly used in rural areas. Catchable species: Puntius spp, Heteropneustis fossilis, Clarius batrachus, Channa straitus, Mystus tengra, Anabus testudineus, etc. b) Hand line with wheel This line is operated by wheel. When fish get stuck with the hook, the wheel is operated to coil the cord. The length of the cord may be 50-60 m. Catchable species: Labeo rohita, Catla catla, Cirrhinus mrigala, Labeo calbasu, etc.
  14. 3. Drift line This line is used to catch fish from the bottom layer. The length of main line may be hundreds meter. The distance between the side line is 0.6 to 1 m. It is used both in shallow and deep water and operated by motor boat. 4. Trawl line Hooks are placed in different depth with the help of trawler. Float, anchor, marked flag, etc. used for placing trawl line. 5. Set line a) Surface water set line b) mid water set line c) bottom water set line
  15. Trolling • Trolling is a method of fishing where one or more fishing lines baited with lures or bait fish are drawn through water. • This may be behind a moving boat or by slowly winding the line in when fishing from a static position or even sweeping the line from side to side. • Trolling is used to catch pelagic fish such as salmon, mackerel and king fish
  16. Spears A spear tip is generally fitted on a bamboo shaft of 1.50 to 2.0 m and operated by throwing on the target from a boat or standing on the bank. 8 types of spears are seen in Bangladesh 1. Aro 2. Chal 3. Ek-katya 4. Juti 5. Pecha konch 6. Tenta 7. Sat-pahla 8. Thur kunch
  17. Float and Buoy • Floats are used to keep a fishing net in a proper shape in water, whereas, buoys are attached to the fishing gear to show its location. • Wood, cork, bamboo, glass ball, iron ball, rubber ball have been used as material of float since old age • Now floats are made of synthetic resin; principal material for floats and buoys are polyvinyl chloride • Floats are cylindrical, globular or oval • floats are mainly porous type and buoys are hollow type or balloon type.
  18. Required properties of float and buoy: - Great buoyancy - Less decrease in buoyancy under high water pressure - Long age - Ease of manufacturing and modeling - Ample supply and low cost
  19. Buoy
  20. Sinker • Sinkers for angling as well as for ground line of nets are made of lead or iron with higher specific gravity. • They are cheap and easy to make. • They are globular, conical and cylindrical in shape