ALAT TANGKAP IKAN JARING INSANG GILLNET

Summary

Gillnet fishing is a popular, passive, and eco-friendly method used by Indonesian fishermen. It is a versatile tool that can be deployed in various water depths and types, such as coastal, oceanic, and deep-sea environments. The gillnet works by trapping fish by their gills, with specific materials and textures that ensure smooth and elastic netting. The net operates vertically, passive in nature, capturing fish based on their size by adjusting the mesh size. It is typically deployed using a variety of boat types, from small sailboats to large motorized ships, with some gillnets spanning kilometers.

Takeaways

• 😀 Gillnets (Juned) are widely used by Indonesian fishermen to catch fish in different water layers, from the surface to the bottom.
• 😀 Gillnets are passive and selective fishing tools that are eco-friendly and designed to trap fish by their gills.
• 😀 The mesh of the gillnet must be smooth, elastic, and round to ensure fish are trapped effectively.
• 😀 Gillnets are typically rectangular in shape and are supported by ropes (called 'ris') that regulate the net's size and depth.
• 😀 The top part of the net is attached to flotation devices (buoys), and the bottom is weighted with sinkers, enabling it to stay in the desired water layer.
• 😀 Gillnets are used to capture fish of various sizes, but mesh size can be adjusted to allow smaller fish to escape, promoting sustainable fishing.
• 😀 The fishing net operates passively, waiting for fish to swim into it and become trapped, which is influenced by water currents and fish movement.
• 😀 Different types of gillnets are used based on the depth of the water: surface nets have greater buoyancy, mid-water nets have equal buoyancy and sinking power, and bottom nets sink more due to their higher weight.
• 😀 Small fishing boats (usually up to 50 GT) use gillnets, but large boats (over 50 GT) can deploy nets that extend for tens of kilometers in open seas.
• 😀 Fish species commonly caught by gillnets include mackerel, tuna, sharks, and marlin, though occasionally larger fish may also get caught in the net.
• 😀 The passive nature of gillnets allows them to be used with minimal manual effort, making them efficient for a variety of fishing environments.

Q & A

What is a gillnet and how is it used in fishing?

A gillnet is a passive, selective, and environmentally friendly fishing tool used by fishermen in Indonesia. It is designed to catch fish by entangling them through their gills. The net operates at various depths, from surface waters to the seafloor, and can be used in coastal, sea, and oceanic waters.

What makes gillnets a passive and selective fishing method?

Gillnets are considered passive because they do not actively chase or hunt fish. They trap fish that swim into them, specifically targeting fish based on their size. This makes them selective, as smaller fish can escape if their size is smaller than the net’s mesh size.

What are the key features of a gillnet's design?

A gillnet typically has a rectangular shape, with four ropes attached to its sides. The top and bottom ropes are called 'risks', while the vertical sides are 'side risks'. The top has floatation devices (pelampung) and the bottom has weights (pemberat) to regulate the net's position in the water.

How do the floatation and weighting systems in a gillnet work?

The floatation devices (pelampung) are placed at the top of the gillnet to keep it afloat at the water's surface. The weights (pemberat) at the bottom help the net to sink and remain at the desired depth, allowing the gillnet to be used effectively at various water layers.

What determines the position of a gillnet in the water?

The position of the gillnet in the water is determined by the floatation and weighting systems. If used near the surface, it has more buoyancy than weight. In mid-water, buoyancy and weight are balanced. In deeper water, the net has more weight than buoyancy to ensure it sinks properly.

How does a gillnet trap fish?

A gillnet traps fish by entangling them in the mesh, especially around their gills. If the fish’s body size is larger than the mesh, it becomes trapped. If the fish is smaller, it can escape. This selective trapping allows control over the size of fish caught.

What role does the mesh size of the gillnet play in its operation?

The mesh size of a gillnet is crucial in determining which fish are caught. If the mesh is large, only larger fish will get trapped, while smaller fish can swim through. This allows fishermen to control the size of the catch and avoid capturing juvenile fish.

What types of fish are commonly caught using gillnets?

Gillnets are typically used to catch fish such as mackerel, tuna, and snapper, as well as smaller fish like sardines. Larger species like sharks and marlins can also get trapped in the net, but they usually do so by becoming entangled.

How does the size of the fishing vessel impact the use of gillnets?

The size of the fishing vessel influences the scale of the gillnet operation. Smaller vessels may use nets of smaller lengths (10-50 meters), while larger ships, such as those over 530 GT, can deploy nets that stretch over several kilometers, especially in deeper waters or international waters.

Why are gillnets considered environmentally friendly?

Gillnets are considered environmentally friendly because they selectively trap fish based on their size, allowing for the release of smaller fish and reducing bycatch. Additionally, the passive nature of the net means it does not actively chase marine life, minimizing disruption to the ecosystem.