2. Introduction
• The tools used to capture the aquatic organisms
are collectively called as fishing gears
• Mainly two type
– Active gears
– Passive gears
• Various types are present.Each variety
determined by target species,availability of
materials,sea bottom,nature of the
coastline,level of mechanization etc..
3. Dredges
• Active gears.
• Used to capture the benthic and sessile organisms
• Usually in the form of metallic frame or cage to
which a strong netting is attached.
• Cage has a “mouth” presented to the sea bed
during fishing.
• It lower jaw usually metal bar teeth like structure
which are 9 to 15cm long.
4. • These teeth harrow the sea bed to disturb the
target species.
• the dredge is dredged ore a soft sea bed where
bivalve molluscs live in the surface mud, which
are trapped in the rear end of the dredge or net.
• Operation of dredges is harm to the nature by
considerably disturbing the sea bed.
6. • Traps large stationary nets or pots or barrier are
gears
Allowing the fish to enter the trap but making it
impossible to leave the catching chamber
• Traps are baited or not
• Traps & pots operate slightly differently from gill
net & entangling nets
8. .When the pot is set on sea
bed , their position may be
marked with surface float
attached to the pot by a line
.In some artisanal fisheries pots
are attached at intervals to a long line
.Design is adapted to target species
.Sometimes a pot will be baited to encourage a target
species to enter it
Crab pot prawn pot lobster pot
9. Advantages
Low cost
One man / family enough to operate
The species caught are economic value
Disadvantages
Sometimes non target species may caught /by catch
Captured species may die relatively quickly and start to decay , if left
too long in the pot
• The object /pot may be cylinder to which hooks are
attached
• These special gears used in spanish mediterranean
coast called ‘cadups’ / ‘cadufs’
• Car tire pieces are used to caught octopus
10. Traps usually bigger than pots
Traps fixed to the sea bed in
shallow or inshore sites
Traps may placed in coastal lagoons
A common type trap is staked to the sea bed &
perpendicular to shore it extends several
meters & the end is curved
11. .Low negative environmental
impact
.Some traps like pots may be
baited to attract species of interest
Baited octopus trap from japan
ff
Barrage trap from coastal flood plain floating- trap
of benin
.Special set nets are used as traps
Eg:- fyke net, stow nets ,pound nets, aerial nets
12. Fyke nets
set in shallow water particularly
in tidal zone
trap in anchored to sea bed
Interior part of fyke
13. Pound nets
.Elaborate structure
.Stake to sea bed in shallow water
.One part of pound net guides the
fish into main pound
.Bottom net shape is prevent
escape
Stow nets
.Usually form of an elongated
cone / pyramid with mouth
which opened by frame
.Stake in the sea bed
.Nets & traps placed with mouth
across current in rivers & estuaries
14. Aerial nets
.Special form of barrier
.set in shallow water between bottom & surface
.Designed to catch jumping fish
Eg:- flying fish
There are some other gears used in artisanal fishery
Eg:- karappu ,sirakuvalai,raal koodu, pari koodu
Karappu
Passive gear
Catch by place around the fish / other organisms
15. Raal koodu
.passive gear
.used for caught prawn &shrimps
.made by bamboo /wooden
Sirakuvalai
.Passive gear
.Very popular in shallow & near shore areas of north SriLanka
.It also known as kurukku valai
.stake net having complicated arrangement
17. • Structure is usually circle with small weights
distributed around its edge
• It is used in shallow water
• The net is thrown by hand in such a manner that it
spreads out on the water and sinks
• This technique is called net casting
• This net is used to catch the small bait and forage
fish
18. • Advantages of cast net are easy of use, value
for money, performs well and perfect cast
every time
• Disadvantages it can be used only in the
artisanal fishery
20. • Lift nets are horizontal netting panels or bag
shaped like pyramid with the opening facing
upwards, they are submerged at the certain
depth
• Lift nets are usually set more or less flat on
the bottom
• These nets are operated by lifting mechanism,
which is normally operated physically by
human
• Lift net is very common along the banks of
river estuaries
21. • Lift nets may be operated from boats or can be
portable and hauled by hand as with purse
seines
• Small pelagic species ,fish ,and squid are
captured by using this net
• Disadvantages relatively low catching power of
lift nets usually limits them to artisanal
fisheries
22. Seine net
• A seine net is a very long net.
• Seines are designed to surround school fish.
• This is active gear
• There are four general type
• Such as :-
• Beachseine
• Lampara net
• Danish seine
• Purse seine
23. • The 1st two now use in artisanal fisheries
• The last two are generally too large to be
operated successfully by artisanal fisherman
• A Seine is with or without a bag , which set
either from the shore or from a boat for
surrounding certain area , and is operated
with two long ropes fixed to its ends
24. • Fish operation
– Seine are usually set from a boat to surround a
certain area and hauled either from the shore or
from the boat its self
25. • Target Species :-mainly demersal species, less
frequently for pelagic species
• Seine nets are operate both in inland and marine
water
• The potential negative impact may consist in the
by catch and results from the use of a large net
with frequently too small meshes in coastal of
water
26. Beach seine
• The beach seine consist essentially of a bag
with along rectangular and relatively narrow
to the bag on either side of the mouth with
cork line and lead line to keep it vertical in the
water for fishing
• It is usually staked at one end to the beach
then from a boat set around a school of fish
.the other wing is then hauled onto the beach
27. Lampara net
• The lampara net is relatively loose and open
net bag with two wings
• It is fished from small boats or along the
beach to catch fish
• Large lampara nets are also operated from
large fishing vessels
28. Danish seine
• The danish seine is smillar to a trawl , a big net
bag with two wings, though fished in a
different way
• It is used to catch fish living just over the
bottom
• It is operated from fishing boat
29. Purse seine
• The purse seine is basically a rectangular en circling
net. with float line and with metal rings attached to
its footrope and threaded onto the purse string
• It is set around the school of fish usually offshore
and off bottom
• Sometimes this gears is used in combination with
night light which encourage schooling fishes to
congregate and become more accessible to a
fishery
30. Gill net
• Gill netting is a common fishing method used
by commercial and artisanal fishermen of all
the oceans and in some freshwater and
estuary areas.
• Gill nets are vertical panels of netting normally
set in a straight line
32. • Fish may be caught by gill nets in 3 ways.
1] wedged-held by the mesh around the body
2] gilled-held by mesh slipping behind the opercula
3]tangled-held by teeth , spines, maxillaries or other
protrusions without the body penetrating the mesh.
• Most often fish are gilled
33. • A fish swims into a net & passes only part way
through the mesh, when it struggles to free
itself, the twine slips behind the gill cover&
prevent escape.
• Gill nets have a high degree of size selectivity.
Most salmon fisheries in particular have an
extremely low incidence of catching non-
target species
35. Types Of Gill Nets
• 1) Set Gill nets
• It consist of a single netting wall kept vertical
by a float line & a weighted ground line.
• By adjusting the designs these nets can fish in
surface layers, in mid water or at the bottom,
targeting pelagic ,demersal or benthic species.
• They are popular with artisanal fisheries ,
because no specialized gear is needed & it is
low cost based on the relationship fuel/fish
36. 2)Encircling gill nets
• These are set vertically in shallow water, with
the floating remaining at the surface so they
encircled fish.
• Small open boats or canoes can be used to set
the net around the fish. Once the fish are
encircled.
• These are commonly used by groups of small
scale fishers, &does not require other
equipment.
37. 3)combined gill nets
• Trammel nets
• This bottom set gear has 2 parts
• The upper part is a standard gill net where
semi demersal or pelagic fish can be gilled.
• The lower part is a trammel net where bottom
fish can entangle.
38. • These are maintained more or less vertically in
the usual way by floats on the floating&
weights on the ground line.
• Traditional combined nets were hauled by
hand, especially on smaller boats.
39. 4)Drift Nets
• It consist of one or more panels of webbing
fastened together.
• Drift nets drift with the current while they are
connected with the operating vessel ,the drift
netter or drifter.
• Usually used to catch schooling forage fish
such as herrings &sardines &also larger
pelagic fish such as tuna, salmon& pelagic
squid.
41. Problem with gill net fishing
• Gill nets work By trapping the fish in the net’s
holes. The fish is able to fit its head through
the holes in the net,but the wider body will
not go through.
• When they try to go to back out,their gils
become hung on the net& fishermen haul
them in. Unintended consequences have
made this method of fishing questionable in
the eyes of many people.
43. It is under nets
Active fishing gear
Cone shaped body
Most versatile fishing technique.
Trawl nets can be operated at
The surface
Mid water
Bottom
Seawater >freshwater bodies
Not used in artisanal fisheries. WHY????fishing gears 43
44. Classification of
trawls
1. Based on mouth opening device
a) Beam trawl
b) Bull trawl
c) Otter trawl
2. Based on the depth of operation
a) Bottom trawl
b) Mid water trawl/Pelagic trawl
3. Based on the construction pattern
a) Two seam trawl
b) Four seam trawl
c) Six seam trawlfishing gears 44
45. • Beam trawl
– Trawl towed on the sea bed in which the net is held open by a wood /steel
beam.
• Bull trawl
– The boat which shoots or hauls the net in bull or pair trawling i.e. by using
two vessels.
• Otter trawl
– Trawl towed on the seabed, held open by a pair of otter boards. It is much
larger net than a beam trawl.
• Bottom trawl
– Trawl towed along the seabed. Those dragged along the bottom.
• Mid water trawl
– Trawls can be towed be in mid water to catch the pelagic species .
• Twin rig trawl
– Method of towing two otter trawls side by side
• Multi rig trawl
– Method of towing two/more otter trawls side by side
fishing gears 45
47. Structure & operation
• Made up from two shaped panels(top & bottom) of netting laced
together at each side to form an elongated ,
• Funnel shaped bag.
• This funnel tapers down to the cod -end .
• Cod- end-:where the fish are collected until the net is hauled.
• The rope at upper edge : headline : has floats
• Side rope : wing lines/gables : weighted ground gear
• Wings connected by bridles/sweeps(length of single wire )
• Doors : steel / wood: attached to boat by warps.
fishing gears 47
48. The mouth of trawl is kept open using devices such
as,
Frame
Beam
Otter board
Kite besides
Floats
Sinkers
Some time trawl net is kept open by two
vessels.
fishing gears 48
The mouth is kept wide opened by long wings
50. Sri - Lanka
• Introduced in 1960s
• 350 Mechanized trawlers in SL.
• Among them 180 trawlers in Gurunagar and rest
are in Mannar, Kalpitiya and Uswattakettiyawa.
• Over 5000 Indian trawlers entering SL’s territorial
waters illegally (north & east)
• Problems: over exploitation
Destroy marine resources
Conflicts among both fishermen(injury, death)
Using monofilament trawlers
Damages the boats, nets
Reducing the local fish production and
increased cost for local fish productionfishing gears 50
51. The countries banned
trawlers
1. Indonesia
2. United states
3. Atlantic waters( >500,000 square miles )
4. New Zealand
5. Mediterranean(Europe& North America)
Reasons
» Increase catches and income for local fisherman
» To end conflicts with industrial trawlers
» Conservation of corals
» To reduce discards
» Protects the nature(seamounts, hydrothermal
vents, corals)
fishing gears 51
52. Advantages
1. Effective
2. Large scale fishing operation
3. Can catch bottom,demersal and
pelagic species
4. Commercially profitable
fishing gears 52
53. Disadvantages
1. Disturbs and destroy the seabed including
seagrasses,coral reefs,rockgardens where fishes hide
from predators, spawning grounds.
2. By catches & discarded valuable fishes(
turtles,seabirds,marine mammals), unwanted fish
caught & thrown away.
3. Compete directly with traditional nets.
4. Overfishing gear is nonselective and discards a lot of
sea fish
5. Direct threat to local fishing communities ,tourism
and sport fishing
6. Illegal fishing in deep sea.
fishing gears 53
54. Mitigating
methods
• Using larger meshes in the cod – ends
• Devices in the trawl that reduce the capture
of small and unwanted organisms.
• TED- Turtle Excluder Device( turtles& sharks)
• Legislation and implementations.
fishing gears 54
56. • A Fishing gear is a tool with which aquatic resources are
captured.
• Same fishing gear can be used in different ways.
• Mainly 5 types
• Nets(trawlers, dredges,gillnet,liftnet,castnets,seines)
• Hook and line
• Traps
• Grappling devices
• Stupefying devices
• Structure/ operation /advantages /disadvantages
fishing gears 56
57. Perform only the ecofriendly
methods to blue sea and do not
disturb the nature and provide
resources to future generation
and improve fishermen socio
economics.
fishing gears 57