Mechanically propelled spears for freshwater fishing are commonly used all over Thailand. Many craft these devices themselves, so there is a wide variety of principles, styles, and designs. Besides homemade spearguns, where every piece is unique, industrial manufacturing is also in place. Some individuals produce many spearguns, e.g., ten at once, and sell them locally and on the Internet.
Technological stages of mechanically propelled spears
The simplest fishing spears consist of a rubber band held by hand, which propels an iron rod forward.
The next technological step forward is a small pipe length with a rubber band at its backside. This pipe can be conveniently held in hand when the spear through the pipe gets drawn backward with the rubber band and will subsequently be released.
The next improvement step is the device mentioned before but with a pistol grip attached. This could also be called a ‘Slingshot speargun’. This way, aiming and releasing the arrow can be done with more natural human hand kinematics. Further devices can be added, like a laser pointer and a reel with a closed spool for the line.
Spearguns in the sense of the word
Further improvement is the stabilization of the holding device. Up to now, this ‘holding device’ was the human hand stretched forward, creating a counterforce to the tension of the rubber bands. By introducing a stock – like a rifle has got – the counterforce to the rubber bands will be consistently moved into the human shoulder. There is no moving wrist, forearm, elbow, or shoulder joint, only one stable piece of wood.
Due to this stable holding device, tensioning the rubber bands to shoot the arrow immediately before release is no longer necessary. The rubber bands can now be tensioned long before shooting and kept in this place. Spearguns with stocks, therefore, need a mechanism for safely holding and releasing the rubber bands, which is incorporated as part of a trigger mechanism similar to rifles.
The action of a particular set of rubber bands can either be increased by additional rubber bands or bow-like limbs for attachment of the rubber strings at the front. These limbs can either have the shape of longbows or recurve bows. Fishing reels or spool-holding devices will also be added to these long-shooting spearguns. Such a speargun is described here in detail.
Nowadays, this is the most technologically advanced stage of homemade spearguns for freshwater fishing in Thailand. Roller spearguns, using pulleys to increase the force of the rubber bands, are currently (2023) only used for speargun fishing in the sea.
Target fish species
In Thailand, every permanent water body is teeming with fish and shrimp. Therefore, a wide variety of fish species serve as potential targets for spearfishing. A study in the UK showed—see here—that fish with a length of below 30 cm have a very low mass and water resistance; therefore, arrows will not penetrate but deflect from them.
This may be the case for the classic use of spearguns in the sea, where the spear is shot through water. However, this does not correspond to the practical use of spearguns in freshwater fishing. Here, the spear is shot through the air and only hits fish swimming on the water’s surface broadside. The remaining energy is by far higher compared to underwater.
Therefore, two general types and shapes of fish will be targeted in Thailand:
- Flat-bodied species of minimum 20 cm / 8’’ length. That’s in most cases outside of fish ponds: Pla Nin (Oreochromis niloticus, Black Tilapia, Thai: ปลานิล) and Pla Ta-phian (Barbonymus spp., Silver barb, Thai: ตะเพียน)
- At least double as long, cylindrical body-shaped fish species. Preferably Pla Sawai (Pangasius hypothalamus, Striped catfish, Thai: ปลาสวาย).
Locations for fishing
Spearguns for freshwater fishing are always used from a location outside the water, that is, from a place elevated over the water’s surface; shooting distances are between 5 and 15 meters.
Preferred locations to position oneself are:
- Bridges,
- Elevated pipeline channels over water,
- Platforms of bridge pillar foundations standing in water,
- Dam walls,
- Sluice gates,
- Elevated riverbanks free of vegetation
- …. and similar places
Speargun fishing is also prevalent in Thailand during floods, which regularly occur along the Chao Praya River from the upper banks to the northern parts of Bangkok. During floods, there are many more locations available for fishing. The water during floods is often shallow, making spotting fish easier. Another advantage of floods (for fishing) is that murky water forces some fish to get to the surface to breathe additional oxygen.
Lessons learned about fishing with mechanically propelled spears in Thailand:
- The simplest method of using a mechanically propelled spear for freshwater fishing is using a rubber band spear.
- Further improvements are a sleeve for guiding the spear and a pistol grip for easier holding and aiming.
- Adding a reel and laser pointer can be beneficial for such slingshot spearguns.
- The next improvement step is to attach all these single devices onto a stock, which takes over the forces of the tensioned rubber bands.
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