Nepedia
Back to Discover
Advanced Reader
💻

Fish trap

technology Maturity 5-7 Next article →

A fish trap is a specialized tool designed to capture fish and other valuable aquatic animals.

Fish trap at Lembeh Strait
Fish trap at Lembeh Strait

These devices are used globally to harvest food or for commercial purposes. Traps are almost universal in human culture. It appears they were invented many times independently across different parts of the world. They range from massive, permanent structures in rivers to small, portable containers. Using these tools helps people manage resources in both fresh and saltwater environments.

Most traps function through a specific mechanical design. One common method uses an inverted funnel to control movement.

うけ瓶の使い方02
うけ瓶の使い方02

This opening is wide at the entrance but narrows significantly as it leads into the trap. An animal swims through the wide opening, often attracted by bait. Once inside, the animal cannot navigate back through the narrow end. Modern cage traps often use a thick steel wire frame shaped like a heart.

Catching crabs
Catching crabs

Chicken wire is stretched around this frame and tapers toward the interior. This ensures the mesh opening bends back to its narrow state, preventing escape.

There are two primary categories of fish traps. The first type consists of permanent or semi-permanent structures. These are placed in specific locations like rivers or tidal areas to catch animals as they move. The second type includes portable bottle or pot traps.

Bubo fish trap - Philippines 09
Bubo fish trap - Philippines 09

These are often baited to attract prey and are periodically lifted out of the water by people. Some traps are specialized for specific habitats, such as the Bubu traps used in Southeast Asia. These are made of bamboo or rattan and are shaped to fit the uneven terrain of coral reefs.

Human history is deeply connected to the development of trapping technology.

Valkenburg De Woerd visfuik
Valkenburg De Woerd visfuik

In South Africa, some intertidal stonewall traps date back 3,000 years. Even older systems exist at Budj Bim in southern Victoria. Indigenous people there created an elaborate system of canals, some exceeding 2 km in length.

Lobster pots at Beer, Devon
Lobster pots at Beer, Devon

This system of aquaculture is at least 6,600 years old. This makes it older than the Pyramids of Giza. In Australia, the Brewarrina fish traps on the Barwon River were used to catch large numbers of migratory fish during floods.

Different animals require different trapping methods and structures.

蛸壺(明石)P5231862
蛸壺(明石)P5231862

In Japan and the Mediterranean, heavy earthenware pots are used to catch octopuses. These animals enter the pots seeking shelter and protection rather than being lured by bait. Lobster pots are often constructed in two distinct parts. The lobster enters a section called the "kitchen" to find bait. It then moves into a second section called the "parlour," where it becomes trapped. In the Philippines, Salambáw are raft-operated lift nets that use a crane mechanism to raise large nets.

While traps are effective, they can cause significant environmental challenges.

West Mediterranean sea topographic map
West Mediterranean sea topographic map

Lost or abandoned traps contribute to the problem of marine debris. In Bristol Bay, Alaska, fishers lost 31,600 crab traps during a two-year period. In the Chesapeake Bay, between 12 and 20 percent of crab traps are lost or abandoned every year. These abandoned traps can continue to catch animals unintentionally. They can also capture protected species, such as the platypus in Australia. Using biodegradable materials can help reduce these long-term impacts.

Some researchers look at the natural world as a giant version of these tools.

West Mediterranean sea topographic map
West Mediterranean sea topographic map

The Mediterranean Sea is sometimes described as the world's largest fish trap. It has an area of about 2.5 million square kilometers. The sea is shaped in a way that mimics a bottle trap. It is easy for fish to swim from the Atlantic Ocean into the Mediterranean through the narrow neck at Gibraltar. However, it is very difficult for them to find their way back out. This geological feature creates a massive, natural collection system for marine life.

621 words

Where will your curiosity go next?

Keep exploring at your chosen reading level.

🖼️ Images & Media (25)
File:Đó.jpg
Đó.jpg
File:Fish trap at Lembeh Strait.jpg
Fish trap at Lembeh Strait.jpg
File:Myles Birket Foster The Eel Traps.jpg
Myles Birket Foster The Eel Traps.jpg
File:West Mediterranean sea topographic map.svg
West Mediterranean sea topographic map.svg
File:Valkenburg De Woerd visfuik.jpg
Valkenburg De Woerd visfuik.jpg
File:NOR Cod Pot - Phillip Meintzer - Aug 2016.jpg
NOR Cod Pot - Phillip Meintzer - Aug 2016.jpg
File:うけ瓶の使い方02.png
うけ瓶の使い方02.png
File:Bubo fish trap - Philippines 09.jpg
Bubo fish trap - Philippines 09.jpg
File:Catching crabs.jpg
Catching crabs.jpg
File:Fuiken.jpg
Fuiken.jpg
File:Katiskaa kokemassa.jpg
Katiskaa kokemassa.jpg
File:Lobster pots at Beer, Devon.JPG
Lobster pots at Beer, Devon.JPG

+ 13 more

More to explore

🔬 Go deeper

More advanced topics to explore

🪜 Step back

Simpler topics to build understanding

What is Nepedia?

A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.