What is long line fishing?

What is long line fishing?

Table of Contents



Long-line fishing is a commercial fishing technique that involves the use of a long line with multiple baited hooks to catch fish. This method is widely used around the world and is particularly popular for catching certain species such as tuna and swordfish. In this article, we will dive deeper into the topic of long-line fishing, exploring its process, equipment used, environmental concerns, and its impact on marine ecosystems.

The Process of Long-Line Fishing

Long-line fishing involves deploying a long line, often several kilometers in length, with numerous baited hooks attached at regular intervals. The line is typically set at a certain depth in the water column, targeting specific fish species that inhabit that depth range. Once the line is set, it is left in the water for a period of time, allowing the bait to attract fish.

Fishermen then return to the line and retrieve it, manually removing the caught fish from the hooks. This process can be labor-intensive and time-consuming, especially when dealing with long lines that may have hundreds or even thousands of hooks. The caught fish are usually stored on board the fishing vessel and either processed on-site or transported to shore for further processing and distribution.

Equipment Used in Long-Line Fishing

Long-line fishing requires specific equipment to effectively catch fish. The main components include:

Mainline: The mainline is a long, durable fishing line that serves as the foundation for the entire setup. It is usually made of strong synthetic materials such as nylon or polyethylene.

Branch lines: Branch lines, also known as snoods, are shorter lines attached to the mainline at regular intervals. These lines hold the baited hooks and are often made of monofilament or multifilament materials.

Floats and weights: Floats are used to keep the mainline near the water’s surface, while weights are added to the bottom of the line to maintain its position and prevent it from drifting.

Baited hooks: Baited hooks are attached to the branch lines and are designed to attract and catch fish. Different types of hooks may be used depending on the target species and fishing regulations.

Environmental Concerns

While long-line fishing is an effective method for catching large quantities of fish, it also raises several environmental concerns. One of the main issues is bycatch, which refers to the unintentional capture of non-target species. Long-line fishing can result in the incidental capture of marine mammals, sea turtles, seabirds, and other fish species. This bycatch can have significant impacts on these populations, leading to population declines and ecological imbalances.

Another concern is the potential for habitat damage. Long-line fishing can cause damage to sensitive habitats such as coral reefs and seafloor ecosystems when the lines get entangled or dragged along the bottom. This can result in the destruction of essential habitats for many marine species.

Impact on Marine Ecosystems

The widespread use of long-line fishing has had significant impacts on marine ecosystems. Overfishing, driven by the high demand for seafood, has led to the depletion of many fish populations. Targeted species such as tuna and swordfish have experienced declines in their populations, affecting the overall balance of marine ecosystems.

Furthermore, the removal of large predatory fish through long-line fishing can disrupt the food chain, leading to cascading effects on other species. This can result in population explosions of certain prey species and the decline of others, causing imbalances in the ecosystem.


Long-line fishing is a commercial fishing technique that involves the use of a long line with multiple baited hooks. It is an efficient method for catching fish, but it also raises environmental concerns such as bycatch and habitat damage. The widespread use of long-line fishing has had a significant impact on marine ecosystems, leading to overfishing and disruptions in the food chain. It is crucial to find sustainable fishing practices and regulations to mitigate these impacts and ensure the long-term health of our oceans.


– Food and Agriculture Organization of the United Nations: www.fao.org
– National Oceanic and Atmospheric Administration: www.noaa.gov
– Marine Stewardship Council: www.msc.org