| FAO/FIIT Fishing Gear Type Fact-Sheet |
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Boat seines [SV] | updated : 10-mai-2001 |
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ISSCFG Classification :
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> | Category : Seine nets |
> | Type : Boat seines |
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Profile |
General Description: The boat seines consists basically of a
conical netting body, two relatively long wings and a bag.
An important component for the capture efficiency of boat
seines is the long ropes extending from the wings, which are
used to encircle a large area. Many seine nets are very
similar in design to trawl nets. Frequently, however,
the wings are longer than on trawls.
Thegroundrope is usually a fairly
heavy rope weighted with lead rings or hanging lead ropes.
The seine ropes are made from synthetic fibre ropes with a
lead core or from a combination of ropes. |
Specific Handling Equipment: In medium and large sized vessels
special rope hauling (a small but
fastwinch)
andcoiling machinery is
installed on deck. The long ropes are often coiled in bins
(on or below the deck) but on modern seiners these
are stored on large hydraulic reels. For hauling the net
hydraulically operated power blocks are used. In smaller
boats seine nets are manually operated. |
Fishing Vessels using this gear:
Seine net boats range in size
from relatively small10 m up to about 30 m
in length. |
Fishing Operations: Seine netting as originally developed,
included setting of an anchored dahn
(marker)buoy from where a first
one drag line was set, followed by one of the wing, the
bagnet, the second wing and finally the second dragline when
the boat comes back to the anchored buoy simultaneously. The
whole gear is encircling a large area in more or less a
triangular pattern. The net is back by the anchored boat,
which is done by hauling the two drag lines simultaneously
with the help of the winches, first relatively slowly and
increasing to a larger hauling speed when the net is nearly
closed. The use of an anchor is often referred to
asDanish Seining. Fish inside
the ropes are frightened into the forward moving path of the
seine net where they are subsequently overtaken by the net
and captured. Another boat seine technique is similar, but
is not using and anchor. Instead the boat is keep stationary
during haul back with the propeller. This technique is often
referred to asScottish seining
ofFly dragging. |
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Features |
Target Species: Mainly demersal but to a lesser extent
also pelagic species. |
The Gear and its Environment:
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| Deployment Area: Seine nets are operated both in inland
and in marine waters. The catching area depends on the
length of the ropes; catching depth is shallower than 50
m in lakes and down till 500 m in marine waters. The
techniques is most efficient on flat and smooth bottom
when long ropes (2500 m) can be used. Boat seines are
also used in rougher grounds, but then with shorter
ropes. In some areas are boat seines used to catch
schooling fish off the bottom. |
| Impact on Aquatic Species: The impact on living resources are
similar to that for trawls as small meshes in the
codend may result in capture of undersized fish and
sometimes non-target species. |
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