Selecting The Line
Almost any kind of line or twine can be used for a handline. However, there are several considerations to take into account before deciding upon the most suitable type. The first action is to decide what fish or type offish you want to catch. This decision may be determined by preferred taste or commercial or sale value, but it also involves the size and power of the fish concerned.
If the target fish is large, then a strong line is needed; if small, then a line with less strength is needed. Here the problem is in choosing the most suitable line. It must be strong enough to hold the fish and withstand the combined force of its weight, swimming power and determination to escape. (Some small fish fight hard and put up a lot of resistance to being caught, while others, sometimes large, give up easily and with only small resistance.) On the other hand, it should be as thin as possible to make it less visible to the fish and less likely to distract the fish from taking the bait. A thick line is more easily detected than a thin line and may disturb the fish or make it very reluctant to take the bait. A thin line is less disturbing and less easily detected.
You should keep in mind, however, that not all thick lines are strong and not all thin lines are weak. This is particularly true of the thin transparent nylon or polyamide lines which not only are difficult for the fish to see but are also very strong in relation to their size (see Tables 1 to 3).
Generally speaking, the lighter the line the more effective it is for catching fish, while the thicker the line in relation to the size of the fish, the less effective. It is for this reason that a large, strong line should not be chosen for catching small fish. A light line is also more sensitive to feel in the hand and helps the handliner determine whether the bait is being played with, nibbled at by very small fish or taken into the fish's mouth without being swallowed. Striking the line too soon to secure the hook in the fish's mouth will lead to its escape. The feel or sensitivity of the line is important to achieving a successful catch.
Most fishermen use nylon (polyamide) for their handlines. Three main types are suitable: braided, twisted and monofilament (Figure 2).
Figure 2. Types of twine: (a) braided; (b) twisted; (c) monofilament
In theory, the fish weighs very little when it is in the water, and the load on the line will depend on how large the fish is, how much it struggles and the speed with which it is pulled up.
Assuming that the maximum load you expect to pull is 15 kg, then considering the jerk you give to the line and the additional force the fish will give in trying to break away, you must use a line capable of taking three times that load without breaking, i.e. 45 kg. This means that the knotted breaking strength of the line must be 45 kg in water, as it has to be knotted to tie the line to the sinker and also to tie the branch lines or the snoods to the main line. The dry breaking strength of a line is the force measured in kilograms that is needed to break the line when it is dry and is pulled straight without a knot. When the line is wet and has a knot or knots, much less force is needed to break it.
Now look at Tables 1 to 3, which give the breaking strength of several thicknesses of twisted, monofilament and braided nylon twine. The wet knotted figure should be used in choosing the twine. The tables also show how many metres of such twine should be in 1 kg, so that the correct amount of twine can be purchased.
From Table 1 you will see, as an example, that twisted twine of 210/21 denier is 0.80 mm thick and when wet and knotted has only 18 kg breaking strength or breaking load. Monofilament twine of the same thickness, 0.80 mm, has less breaking strength, only 15 kg, when wet and knotted (Table 2). You will also note that if you purchase 1 kg of 0.80 mm twine you will get about 1 850 m of twisted twine (Table 1) but only 1 670 m of monofilament twine (Table 2).
Let us take another example. Look at a thicker twine suitable for larger fish and deeper water. Twisted twine of 210/60 denier is 1.5 mm thick and has a wet knotted breaking strength of 47 kg, but monofilament of the same thickness has only 46 kg breaking strength and braided twine of the same thickness 44 kg breaking strength.
You will also note that if you purchase 1 kg of each different 1.5 mm twine, then you will receive 590m of twisted, 490 m of monofilament but 740 m of braided twine. Therefore, if there is a choice, it is advisable to check the prices per kilogram and compare the costs of the desired length before deciding what to buy.
Originated by: Fisheries and Aquaculture Department
http://www.fao.org/
Text: B. A. Bjarnason
Illustrations: M. Carlesi
The designations employed and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of the Food and Agriculture Organization of the United Nations concerning the legal status of any country, territory, city or area or of its authorities, or concerning the delimitation of its frontiers or boundaries.
David Lubin Memorial Library Cataloguing in Publication Data
Bjarnason. B.A.
Handlining and squid jigging
(FAO Training Series, no. 23 )
ISBN 92-5-103100-2