A fishing net is a porous, mesh-based device designed to capture fish and other aquatic organisms. Nets act as passive or active capture systems: they may entangle, encircle, surround, or scoop targets. Historically simple in concept, modern nets are engineered tools made with attention to mesh size, twine strength and buoyancy. For a basic definition and comparison with other capture devices see trap and net distinctions.
Construction and components
Most nets consist of interlinked meshes formed from twine or filament. Key components include the mesh (the repeating opening), the twine or strand material, floats to provide buoyancy, and sinklines or weights to keep parts of the net at the desired depth. Mesh size and knotting method determine what species and sizes are retained; many fisheries use mesh selection to reduce juvenile capture. Common materials range from natural fibers to synthetic filaments — consult sources about materials and durability at material choices.
Common types
- Gillnets: set to entangle fish by the gills as they try to back out.
- Seine nets: used to encircle and then close around schools of fish.
- Trawls: towed nets that sweep the water column or seabed.
- Cast nets and dip nets: handheld, used by small-scale or recreational fishers.
Each type has distinct deployment methods, gear requirements and target species. Vessel size, habitat and legal restrictions all influence which net is appropriate.
History and development
People have used woven nets for fishing for many millennia. Early nets were made from plant fibers and animal sinew; with the industrial era came cotton and then synthetic polymers such as nylon and polyethylene, which offer greater strength, resistance to rot and consistent mesh sizes. Technological advances also introduced mechanized hauling, acoustic locating and design refinements to reduce unwanted catch.
Uses, impacts and management
Nets are essential to both commercial and artisanal fisheries because they can efficiently harvest large volumes. However, net use raises ecological concerns: bycatch of non-target species, habitat damage from bottom trawling, and lost or abandoned nets that continue to catch animals (known as ghost fishing). Fisheries management, mesh regulations, seasonal closures and gear-selectivity measures are widely used to mitigate these impacts; see regulatory guidance at regulations and best practice.
Proper maintenance extends net life and reduces hazards: inspect for tears, replace floats and weights, store dry to avoid rot, and mark gear to aid recovery. Detailed handling and repair techniques are covered in many fisheries guides and training resources such as best-practice manuals.