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					     DEEP-WATER SNAPPER FISHING GEAR AND TECHNIQUES USED
                    IN THE PACIFIC REGION
                                                              by
                                                       Lindsay Chapman

INTRODUCTION
Fishing for deep-water snappers in depths
from 100 to 400 m, and sometimes deeper,
has been practised for generations in some                                           Coconut fibre
of the remote island communities of the                                              mainline                       Wooden batten to hold hook
Pacific (Preston et al. 1999). Traditionally,                                                                             away from mainline
Polynesian fishermen used coconut fibre
line, with a stone as a weight, and several
                                                                   Coconut
wooden, bone or shell hooks attached
                                                                   fibre trace
(Figure 1) to fish for these species.                                                                               Hook (originally wooden,
                                                                                                                    bone or shell, now metal)
                        Figure 1: Traditional Polynesian
                                                                                                Stone sinker
                                deep-bottom fishing rig.



Since the introduction of more modern materials in the 1970s, Polynesian and other fishermen have
experimented with a range of gears throughout the region in an attempt to harvest deep-water snapper
species. From the late 1970s, SPC has assisted most Pacific Island countries and territories in the region
(Figure 2) to fish for these species using a range of fishing gears and methods.

                                                                 180˚                  Hawaii
                  Nothern
                  Mariana
                  Islands

                  Guam                    Marshall
                                          Islands
               Federated States of
               Micronesia
       Palau

                   Papua New                                                                                                         Equator
                   Guinea                Nauru        Kiribati
                                                                         Kiribati                Kiribati
                                                        Tuvalu
                                          Solomon                          Tokelau
                                          Islands                                Cook
                                                                   Wallis Samoa Islands
                                                                  Futuna     Am.
                                                          Fiji              Samoa
                         Australia          Vanuatu
                                                                                Niue                        French
                                     New                                                                    Polynesia
                                     Caledonia                          Tonga                                                   Pitcairn
                                                                                                                                Islands




                                                          New
                                                          Zealand

                             Figure 2: The Pacific Island countries and territories in the region


In addition to SPC’s work in the region, other development organisations, including FAO, UNDP,
USAID, Japan, the EU, etc., have funded fishing trials and development projects based on the harvest-
ing of deep-water snappers. This paper tries to summarise the different fishing gear and techniques tri-
alled or used over the last 25 to 30 years to target deep-water snappers in depths from 100 to 400 m,
and draws heavily on the information presented in Preston et al. (1999).
Handreels

The simplest reel introduced to the Pacific in the late 1970s for deep-water snapper fishing was the
FAO design Samoan handreel (Figure 3). The reel can be made from locally available materials and
allowed small-scale fishermen to make these up at minimal cost. The reel post was mounted to the side
of small-scale vessels, while the spool with line and the rocker arm were removable for ease of stor-
age.

                                                                               Rubber shock absorber
                                                                                 (cut from inner tube)


                                                                              Hardwood
                                                                              lever arm
                                                                              rockers
                                                                              stanchion
          Ceramic spike isolator
                                                                              cross-reel
          (electrical type)
                                                                              and handle



         PRINCIPAL DIMENSIONS (mm)           Marine
         Key: L = Length, W = Width,         plywood
               T = Thickness, ø = Diameter   washers                         Split pin
         Reel:
         Axle shaft: 191 L x 16 ø                                           Brass, bronze or steel
         Hardwood: 530 L x 90 W x 38 T                                      shafts for reel axle and
         Washers (ply) : 10 T x 125 ø                                       handle spindle
         Handle: 126 L x 35 ø
         Spindle: 254 L x 12 ø                                               Through bolts to
                                                                              retard splitting
         STANCHION:
         Post: 90 W x 38 T
         Lever arm: 910 L x 88 W x 38 T
         Rockers: 150 L x 90 W x 19 T
                                                Figure 3: FAO design Samoan handreel.



Other commercially made handreels have also been available for local fishermen. However, the cost of
these reels has limited their use in the Pacific region. Commercially manufactured reels have been
designed and built in Australia, Japan and the US (Figure 4) to name a few.




               Figure 4: Commercially manufactured handreels used for deep-water snapper fishing.




                                                       2
Other variations of more low-cost handreels have been developed in the region. In Vanuatu, a French
fisherman mounted a reel spool to a bicycle frame to come up with the ‘velo’ design (Figure 5). Other
designs were just a modification of the original wooden handreel, where it was made larger from steel
for larger boats (Figure 6), or smaller for mounting on traditional outrigger canoes (Figure 7).




   Figure 5: Velo design deep-water snapper reel.                Figure 6: Steel version of a handreel.




                       Figure 7: Modified handreel mounted on a traditional outrigger canoe.



                                                        3
Mainline and terminal rigs used for fishing.

The mainline used for fishing with handreels can be either monofilament or braided lines, such as
super-toto. The line is wound onto the reel, with usually 400 to 500 m used depending on the size of
spool and the depth of water to be fished. Onto the end of the mainline a terminal rig is attached. The
terminal rig can be made of wire or monofilament, and usually has three to five hooks attached (Figure
8). A chum bag can also be attached to the top of the terminal rig.

                                 Barrel swivel with
                                                                                                            Ball-bearing
                                  Coastlock clip
                                                                            Chum bag fixed                   swivel with
  End-loop                                                                   to attachment                        pigtail
  made using                                                                           clip
  double                                 End-loop made using
  figure-8 knot                          double-crimped
                                         Flemish eye

                                                                                                              Chum bag on
                                                                                   End-loop made               upper trace
                                                                                   using haywire          attachment point
                                                                                   twist and
  Nylon                                                                            wrapping
  monofilament
  terminal rig
                                     Trace attachment
                                     loop made using
                                                                                                             Cable trace
                                       harness knot                    Galvanised multi-strand
                                                                         cable terminal rig



 Sinker made                                    Cable trace                 3-way swivel
 from                                                                       used as trace
 concrete               Monofilament trace                                  attachment point
 filled can

                                                              Sinker made from
                                                                     heavy steel
                                                                 reinforcing rod                      Chain sinker


                              Figure 8: Terminal rigs used for deep-water snapper fishing.

Anchor gear and use

The anchor gear used when deep-water snapper fishing is simple in construction, and consists of a grap-
nel anchor made from rebar (Figure 9) and around 400 to 500 m of polypropylene rope. The size of the
rebar and rope used depends on the size and weight of boat using the gear. A large PVC balloon buoy
or float (Figure 9), or several longline floats tied together, are used in the retrieval of the anchor at the
end of fishing.
    60 – 70 cm diameter                                           5 – 15 kg grapnel anchor made from
    (70 – 120 kg flotation) inflatable                                 reinforcing rod and steel piping
    PVC baloon buoy



                                                                                  5 – 10 m of
                                                                             8 – 12 mm chain

                                         Galvanised wire barb whipped onto rope



                                                         10 mm polypropylene anchor rope

                              Figure 9: Anchor gear used for deep-water snapper fishing.


                                                           4
At the end of fishing a simple method is used to retrieve the anchor. The slack rope is pulled in until
the rope is taught and vertical in the water. The rope is then secured to the boat as it speeds up and over
the anchor, breaking it free from the bottom (Figure 10). As the rope streams out behind the moving
boat, the buoy is attached to the rope and allowed to slide back until it is trapped by the no-return barb
that is whipped to the rope. With the rope floating on the surface, the boat is turned and motored along
as one person pulls the rope in (Figure 10). When the anchor is reached, it is pulled onboard as well.


      a) Vessel anchored for fishing.         b) After fishing, anchor warp is secured to strong point
                                                 and anchor broken out by towing at low speed.




                                                                                      c) Anchor is then brought
                                                                                         to surface by towing
                                                                                         at high speed.




                                                                     d) When anchor is streaming behind boat,
                                                                        buoy is clipped onto anchor warp and
                                                                        release.




       e) Buoy is dragged back along warp, bringing anchor to surface.




       f) Boat turns around and warp is retrieved, anchor hangs at surface, suspended by buoy and ‘no-return’ bard.




                                    Figure 10: Retrieving the anchor after fishing.




                                                           5
An alternative to anchoring to fish for deep-water snapper is to use a controlled drift. To do this a para-
chute sea anchor is needed (Figure 11). The size of the sea anchor will be determined by the size and
weight of the boat it is used on. Bottom longlines
                        Float
                                             Haul-in line



                       Trip-line
                                                                               Anchor line
                                                                Swivel
     3-way
     swivel


      Sinker                                                Shrouds



                            Figure 11: Parachute sea anchor used for controlled drifting.

To set a sea anchor, it is simply lowered over the bow of the boat. The trip-line and float attached to
the apex of the sea anchor are also paid out as the sea anchor fills, and allowed to float free with no
tension. Once some resistance is felt, the anchor rope is paid out to the desired length and secured.
Hauling the sea anchor is the reverse of setting. The trip-line is hauled in to turn the parachute around
so it is pulled in by the apex. Once this is retrieved, the anchor line is pulled in.

Powered reels

In some locations, handreels have been replaced by powered reels. The same principle applies; how-
ever, electric motors or hydraulics are used to wind the reel, and hopefully fish, up to the boat. There
is a range of commercially made reels available. In the 1980s and 1990s, these reels were simple, with
either the line wound onto a spool (Figure 12) or a pinch-puller (Figure 13) used to haul the line, with
the line coiled into a basket.




                                                                                    Figure 13: Pinch-puller used for
        Figure 12: Electric and hydraulic reels used with spools.                       to wind the mainline on.

Powered reels are becoming more sophisticated by the
year, and newer versions have computer technology
where they can be programmed (Figure 14) to lower the
line to a specific depth, jig the line if desired, and auto-
matically haul up when weight is put on the line, such as
a fish being hooked. The reel will also stop winding
when the terminal rig reaches the surface, as this is all
programmed into the reel as well.

The types of terminal rigs used with powered reels are
the same as for the handreels. The anchor gear and the                   Figure 14: One type of programmable electric
sea anchor are also the same.                                              reel used for deep-water snapper fishing.

                                                            6
The next step up from using handlines is to use some form of longline, whether it be set horizontal or
vertical. With bottom-set longlines, the mainline and baited hooks are set along and in contact with the
ocean floor. The mainline is generally made from negatively buoyant rope so that it rests on the bot-
tom. Sometimes additional weights are attached along the mainline to reduce the chance of fish or cur-
rents moving the mainline and getting it tangled on the bottom (Chapman 1990). The mainline usual-
ly has a haul-in line on each end, with a float to mark the position and support the weight of the haul-
in line (Figure 15). The mainline is generally 250 to 350 m long, although this can be altered to suit the
operation of the boat and the depth of water being fished. A general rule is to have the mainline short-
er that the depth of water being worked, so that when the first hook reached the surface the fisherman
knows the last hook is off the bottom. The hooks are on individual snoods around 30 to 40 cm long,
with a longline clip on the other end. The snoods are snapped onto the mainline at around one-metre
intervals. This type of gear is generally used on a flat bottom with few obstacles, to reduce the chance
of the mainline becoming stuck on the bottom. This type of gear has not been very successful in the
Pacific due to the rough nature of the bottom being fished, which has resulted in considerable gear loss.




                                6 mm kuralon haul-in line


                                         Mainline of 6 mm kuralon,
                                         250 – 350 m long                     2 – 3 kg weight




              5 – 8 kg weight         2 – 3 kg weight
                                                                                                  5 – 8 kg weight


                      Figure 15: One type of bottom longline with a haul-in line at each end.


An alternative type of bottom-set longline is being used in some locations in the Pacific due to the
rough bottom being fished. In this case, a short mainline of 100 to 150 m in length is used, and the
mainline is made from polypropylene rope, which is positively buoyant (Figure 16). The snoods and
spacing along the mainline are the same as other bottom longlines, and there is generally only one haul-
in line as the mainline is so short. This type of gear has been more successful in the Pacific as it is short
and can be better targeted, and there is less chance of getting the gear snagged on the bottom, with less
gear loss.




                                       6 – 10 mm polypropylene haul-in line


                                               Mainline 6 – 10 mm polypropylene rope, 100 – 150 m long




                     Figure 16: Alternative bottom longline using polypropylene rope mainline.




                                                            7
Setting a bottom set longline

The most common and safest way to set bottom longlines from small craft is to use a shooting rail. The
rail is a piece of aluminium ‘U’ or channel beam or equivalent. The snoods are prepared by baiting each
hook and placing it in the ‘U’ or channel beam. The snap is allowed to hang down from the beam
(Figure 17). The snap of each snood is then attached to the mainline in order, with around one metre of
mainline between snaps (Figure 18). When all the snaps are attached to the mainline, it is ready for set-
ting. The anchor or weight at the end of the mainline is let go and it starts to pull the baited hooks of
the shooting rail in order as the boat motors forward. When all the snoods are set, the mainline is tied
off and the boat stretches the mainline out to stop in settling in a pile on the bottom. When the main-
line is stretched, the second anchor or weight is released and the haul-in line paid out. The float is then
released and the gear allowed to settle and soak.




      Figure 17: Baited snoods lined up in the ‘U’            Figure 18: Snood snaps attached to the mainline
                   or channel beam.                                     ready for shooting the gear.



Hauling the gear

The gear is easily hauled using a line hauler that
is mounted close to the side of the boat (Figure
19). The float is retrieved and the haul-in line
passed over the line guide (Figure 19) or block
and onto the hauler. The rope is then closely
monitored as it is hauled until the first anchor or
weight is reached. The hauler is stopped, the
anchor or weight removed, and the hauling con-
tinued slowly with each snap being removed
from the mainline as it comes into reach. When
larger fish are on the line, the hauler is stopped
to allow the fish to be gaffed and boated.

                     Figure 19: One type of line hauler
                         used to haul bottom longlines.




                                                          8
Trotlines

Trotlines are an alternative to bottom-set longlines. The main difference is that the mainline is sus-
pended horizontally above the bottom, so it does not come in contact with the ocean floor and become
stuck. There have been several types of trotline arrangements used or trialled over the years in the
Pacific.

The ‘Florida fish stick’ uses short lengths of
PVC tubing with a weight on one end and a
pressure float and snap attached to the other
(Figure 20). Holes are drilled through the PVC
and a snood is passed through and secured,
with a hook placed on each end. The fish sticks
are then attached to the mainline as it is paid
out during setting, so that each stick’s weight is
on the bottom with the pressure float keeping it
vertical in the water (Figure 20). Although this
method has been used in several locations in
the Pacific, it has not been successful as the fish
sticks are costly, easily broken, and very diffi-
cult to handle on the boat, so they are no longer
used in the region.                                                 Figure 20: The ‘Florida fish stick’ type of trotline.


                                                          Surface
                                                          float           Other trotline arrangements have the
         Radio transmitter buoy surface float
                                                                          trots or droppers made of monofilament,
                                                                          wire or light cord rather than PVC pipe.
                                                                          The basic design is the same; however,
                                        Haul-in line
                                                                          the trots are much easier to handle on the
                                                                          boat and easily stored. Another small
                                        Pressure floats                   difference is that the weight at the bot-
                        Mainline
                                                                          tom of each trot is usually sacrificial, and
                                                                          is attached to the trot by a light cord.
                                   Droppers
                                                                          This is to allow it to break off if it gets
                                                Snoods
                                   or trots                               stuck on the bottom. Figures 21 and 22
                                                                          show two trotline arrangements.
Figure 21: A trotline arrangement with the mainline attached to
the anchor or weight.
                                                                                Longline clip
                                                                                with swivel




                                                                          20 – 30 cm of
                                                                          80 – 100 kg test                      1.5 m of
              0.5 – 1.0 kg lift                                           monofilament                  130 – 150 kg test
              pressure float                                              with hook                        monofilament
              400 m depth

                                                                                                         Light break away
                                                                                                            in case weight
                                                                                                              gets stuck on
                                                                                                                     bottom
                                                                                    Weight of
                                                                                    1 kg

                   Figure 22: A trotline arrangement with the mainline attached to the haul-in lines


                                                            9
The length of each trot is usually around 1.5 to 2 m, so that the three to five hooks are kept relatively
close to the bottom. Trotlines are set and hauled in the same manner as bottom-set longlines. The main
difference is that the trots are generally attached to the mainline as it is being paid out (no shooting rail
used). Like bottom-set longlines, the length of the mainline is shorter than the depth of water being
fished. These types of trotlines are still used in a few locations in the Pacific, especially some
Melanesian countries.

Droplines

A few species of deep-water snappers are known to school up and rise off the bottom. For these species,
a dropline can be used. A dropline is a single line (haul-in line and mainline) set vertically, with a
weight on the bottom and a marker float on the top (Figure 23). From 5 to 50 snoods can be spaced at
50 to 80 cm intervals along the bottom portion of the line, from the bottom up (Figure 23). Just above
the top hook, a small pressure float is attached to ensure the mainline is kept vertical and the hooks are
kept off the bottom.

                Large marker float supporting line                          Dan buoy with flag




                   Small float attached to mainline
                   to keep the line taught
                                                            Snoods made from heavy twine or monofilament
               6 to 10 mm mainline around 300               25 to 30 cm long with a longline clip attached to
               to 500 m long with snoods                                   one end a circle hook at the other
               attached every 50 to 80 cm




                          5 to 10 kg weight



                                          Figure 23: Dropline arrangement


Droplines are generally set using a shooting rail the same as described above for bottom-set longlines.
The difference is that the boat is stationary so the weight takes the hooks straight down so the mainline
is vertical. A rope line hauler is used to retrieve the gear, with the hooks unsnapped from the mainline
as they come aboard. This method has been trialled in the Pacific, but has not caught on and is rarely
used at present.

Traps

The ‘Z’ trap (Figure 24) has been trialled in several coun-           Lifting bridle
                                                                                                  Rebar steel frame
tries in the region with limited success. The design of the
trap is such that it guides fish to one of two entrances in
the wire mesh cage. Once inside, the fish find it difficult
to find a way out. Although the catch rates for deep-water
snappers have been low, it has been reported that in some
locations large numbers of nautilus have been caught as
well as some deep-water shrimps (when fine wire mesh is                                                   Galvanised
                                                                                                           wire mesh
used). This method is not used in the Pacific at present                       Two entrances
due to the high cost of the gear, the low catch rates, and
the potential for gear loss.                                                Figure 24: Basic ‘Z’ trap design.


                                                       10
Trawling

Trawling in the Pacific for deep-water snappers has been trialled on a couple of occasions, especially
on offshore seamounts where the trawl just passes over the top of the seamount where the fish tend to
congregate (Figure 25). This is a method that is not used in the Pacific at present for fishing deep-water
snappers. However, several countries in the region are looking at the possibility of deep-water trawling
in depths of 500 to 2,500 m for other species, and this may occur in the future.


                            Trawler




                                            Warp


                                                                 Otter board
                                                                        Bridles

                                                                                  Trawl




                                  Figure 25: Trawling the top of a seamount.

Conclusions

The main gear used in the Pacific region for deep-water snappers continues to be the handreels and
powered reels. This is due to the low cost of the equipment, the ease in maintaining and repairing the
equipment, and the generally limited fishing area for these species. This type of gear would be used to
some degree in all Pacific Island countries and territories.

Bottom longlining and trotlining are the next most common methods used in the region for deep-water
snappers, although these are mainly used in some of the Melanesian countries where there are larger
fishing areas for these species. The boats used are equipped with hydraulics and the gear is more expen-
sive. In these locations the markets, local and export, will pay a high price for the fish, which warrants
the increased cost of the boats and gear used.

References

Chapman, L. 1990. Certificate in Fishing Operations — fishing technology course notes for year one.
      Australian Maritime College, Launceston, Tasmania. 220 p.

Preston, G., P. Mead, L. Chapman, and P. Taumaia. 1999. Deep-bottom fishing techniques for the
        Pacific Islands — a manual for fishermen. Secretariat of the Pacific Community, Noumea,
        New Caledonia. 82 p.




                                                     11