VIETNAM

CONTENTS

Marine Fishing

Explanatory Notes

Trawls

Sourrounding Nets

Seine Nets

Gill Nets

Hook and Lines

Lift Nets

Traps

Cast Nets

Scoop Nets

Miscellaneous

Fishing Gear Monograph

 

REFERENCES

Home

 

Explanatory Notes

       This volume is a result of the surveys on marine fishing gear and methods in Vietnam from January 1997 to December 1999. The survey locations are selected from provinces where fisheries developed and are shown in Figure 1 . The abbreviations and symbols used in illustrations and the surveys are in accordance with the use as in the first, second and third volumes ( Thailand , Malaysia and Philippines ). The number of surveyed fishing gear types is shown in Table 6 . The data, which are introduced in this monograph, were based on the data contained in reports of Vietnamese Ministry of Fisheries and the data from practical surveys conducted by the Research Institute of Marine Products.

llustrations :

     1) Drawing of the horizontal length of surrounding nets, seine net and gill net depends on the length of the float line, and the vertical depth depends on the vertical hanging ratio of netting. In the case of gill nets with side lines, the depth of the side line is drawn same scale to float line. The width of netting panels, or sections of trawl are drawn as a half of the stretched netting width, and the depth or length according to the vertical hanging ratio of netting. Some

Table 6. Amount of fishing gear designs and technical papers collected from the surveys in Vietnam .types of fishing gear are shown by schemata or overall sketches with the dimensions indicated applicably.

                        Group of Fishing gear

Amount of designs

Beam trawl

8

Bottom otter trawl

8

Bottom oter trawl with booms

8

Bottom pair trawl

19

Purse seine

22

Beach seine

2

Drif gill net

22

Bottom gill net

22

Trammel net

9

Hook and line

21

Lift net

12

Traps

14

Cast net

3

Scoop net

6

Dredge

1

 

Total

177

      2) General outline drawings, such as of the rig of a complete gear, and detailed drawings of components, are not to scale, but the main dimensions are given.

     3) Dimensions are given only in meters (m) and millimeters (mm). The units are not indicated but can be easily be recognized, as follows:

Meter : Length of footropes, headlines, floatlines, etc. used with decimals of hundredths (e.g., 5.25, 90.20).

Millimeter : Mesh size (stretched), diameter of ropes, floats, etc. used without decimal or with decimals of tenths (e.g., 15; 325 or 2.5 ; 15.8)

     4) Mass and weight are indicated in the units of kilogram (kg) and gram (g). Buoyancies of floats and sink load of net yams or ropes are shown by kilogram-force (kgf) or gram-force (gf).

     5) Materials are indicated by abbreviations listed in Appendix 1.

     6) The size of net yarns is shown in the denier unit.

     7) The mesh size given in millimeters (mm) is understood to be the distance between the centers of two opposite knots in the same mesh when fully stretched.

     8) The number of meshes in a straight row along the edge shows the width and length or depth of net panels or sections.

     9) The shape of netting section is indicated by the cutting rate at its edge. A tabulation of common cutting rates for a practical rang of taper ratios is shown in Appendix 2 .

   10) The term hanging ratio (E) designates the ratio between the length of a given portion of the mounting rope and the length of the stretched netting hung on this portion of the rope.

   11) When there are two or more variants in the construction of gear or manner of use, there are indicated in the title and opposite thedrawing by Roman numerals (I, II,...). Where these variants refer to only one component part of gear, other possible ways of making this part are shown with the abbreviation ALT.

   12) Sequence in fishing operation is shown by sketches with circled Arabic numerals (1, 2,...) which indicate the sequence of operational stages.

   13) Parts of gear drawn in detail are indicated by circled capital letters (A B...).

Figure 1. Location of fishing gear and metfod survey in the Vietnam       

 

Appendix 1: Abbrivations and symbols used in illustrations

Loa

Length of over all fishing boat

GT

Gross tonnage

Hp

Horse power

EG

Electric generator

LL

Luning lamp

BAM

Bamboo

BR

Brass

CEM

Cement

CLAY

Baked clay

COMB

Combination rope

Fe

Iron

Fp

Foam plastic

MAT

Material

MONO

Monofilament

PA

Polyamid

Pb

Lead

PE

Polyethylene

PL

Plastic

PP

Polypropylen

RUB

Rubber

S

S Twist

SST

Stainless steel

SW

Swivel

WD

Wood

WIRE

Steel wire rope

Z

Z Twist

o/

Diameter

Upper panel

Lower panel

 ll

Side panel

Purse ring

ll

Thichness

Approximately

Circumference

 xxxxx

Braided

   zzzzzz

Twisted

Current

Wind

Apppendix 2: Common Cutting Rates and Taper Rations

 

1

2

3

4

5

6

7

8

9

10

1

AB

1T2B

1T1B

3T2B

2T1B

5T2B

3T1B

7T2B

4T1B

9T2B

2

1N2B

AB

1T4B

1T2B

3T4B

1T1B

5T4B

3T2B

7T4B

2T1B

3

1N1B

1N4B

AB

1T6B

1T3B

1T2B

2T3B

5T6B

1T1B

7T6B

4

3N2B

1N2B

1N6B

AB

1T8B

1T4B

3T8B

1T2B

5T8B

3T4B

5

2N1B

3N4B

1N3B

1N8B

AB

1T10B

1T5B

3T10B

2T5B

1T2B

6

5N2B

1N1B

1N2B

1N4B

1N10B

AB

1T14B

1T7B

1T4B

1T3B

7

3N1B

5N4B

2N3B

3N8B

1N5B

1N12B

AB

1T14B

1T7B

3T14B

8

1N2B

3N2B

5N6B

1N2B

3N10B

1N6B

1N14B

AB

1T16B

1T8B

9

4N1B

7N4B

1N1B

5N8B

2N5B

1N4B

1N7B

1N16B

AB

1T18B

10

9N2B

2N1B

7N6B

3N4B

1N2B

1N3B

3N14B

1N8B

1N18B

AB

11

5N1B

9N4B

4N3B

7N8B

3N5B

5N12B

2N7B

3N16B

1N9B

1N20B

12

11N2B

5N2B

3N2B

1N1B

7N10B

1N2B

5N14B

1N4B

1N6B

1N10B

13

6N1B

11N4B

5N3B

9N8B

4N5B

7N12B

3N7B

5N16B

2N9B

3N20B

14

13N2B

3N1B

11N6B

5N3B

9N10B

2N3B

1N2B

3N8B

5N18B

1N5B

15

7N1B

13N4B

2N1B

11N8B

1N1B

3N4B

4N7B

7N16B

1N3B

1N4B

16

15N2B

7N2B

13N6B

3N2B

11N10B

5N6B

9N14B

1N2B

7N18B

3N10B

17

8N1B

15N4B

7N3B

13N8B

6N5B

11N12B

5N7B

9N16B

4N9B

7N20B

18

17N2B

4N1B

5N2B

7N4B

13N10B

1N1B

11N14B

5N8B

1N2B

2N5B

19

9N1B

17N4B

8N3B

15N8B

7N5B

13N12B

6N7B

11N16B

5N9B

9N20B

 

Row: Number of meshes depth

Column: Number of meshes lost ( or gained )