Purse seine fishing is a commercial fishing method that uses large circular nets to encircle schools of tuna swimming near the ocean’s surface. The net forms a wall around the fish, then closes at the bottom like a drawstring purse to trap the entire school. This technique is one of the most efficient ways to catch tuna that travel in groups, making it a dominant method in commercial tuna fishing operations worldwide.
What is purse seine fishing and how does it work?
Purse seine fishing operates through a systematic process involving multiple vessels and specialized equipment:
- School detection and positioning – Fishing vessels locate tuna schools using sonar technology, helicopter spotting, or visual identification from the crow’s nest
- Net deployment and encirclement – The main vessel releases one end of the massive net while circling the fish at high speed, with a smaller skiff boat holding the opposite end
- Purse closure activation – Steel rings along the net’s bottom allow a cable to run through them, which when pulled tight closes the net like a drawstring bag
- Net retrieval and fish collection – The entire net is hauled aboard using powerful winches, bringing the trapped tuna with it
The net can stretch over a mile long and reach depths of several hundred feet. The purse closure prevents fish from escaping downward during retrieval, ensuring maximum catch efficiency.
Why do fishing companies choose purse seines for tuna?
Commercial fishing operations prefer purse seines due to several advantages:
- High-volume catches – A single deployment can capture dozens of tons of tuna, far outperforming hook-and-line methods
- Species-specific targeting – Tuna naturally form dense surface schools during feeding and migration, making them ideal for seine fishing
- Operational efficiency – Successful operations can be completed in hours, reducing fuel and crew costs
- Cost-effectiveness – Large-volume captures translate directly into higher profit margins in global markets
This combination of natural fish behavior and technological capability has made purse seining the dominant commercial method for tuna fishing worldwide.
What types of tuna are caught using purse seine methods?
Seine net fishing targets specific tuna species based on schooling behavior and market value:
- Skipjack tuna – Largest global catch volume due to dense surface schooling and active daylight feeding
- Yellowfin tuna – Often caught in mixed schools or around floating objects, commanding higher market prices
- Bigeye tuna – Frequently found near seamounts and FADs, valued for premium sashimi markets
- Regional variations – Pacific operations target mixed-species schools while Atlantic fishing focuses on seasonal migration concentrations
Skipjack are particularly well-suited to purse seining due to their large, dense surface schools, while yellowfin and bigeye often provide higher-value catches that improve overall trip profitability.
How does purse seine fishing impact tuna sustainability?
Modern purse seine practices increasingly address environmental concerns through:
- Bycatch management – Gear modifications and selective FAD fishing reduce unintended captures of dolphins, juvenile tuna, and other species
- Quota compliance – Regional Fisheries Management Organizations establish science-based catch limits to prevent overfishing
- Certification programs – MSC and ISSF standards provide frameworks for sustainable fishing with regular monitoring
- Technology improvements – Advanced monitoring systems enable more selective targeting of mature tuna schools
The industry increasingly recognizes that long-term profitability depends on healthy fish populations, with regulatory frameworks ensuring purse seine fishing can meet global demand while maintaining ecological balance.
How SmarTuna helps with purse seine fishing traceability
SmarTuna provides comprehensive traceability for purse seine operations by capturing real-time vessel data from the moment fishing begins, using satellite VMS and AIS tracking for complete visibility into where and how tuna are caught.
Key capabilities include:
- Real-time vessel monitoring – Continuous satellite tracking of fishing vessel movements throughout operations
- Unique batch identification – Raw material IDs assigned at port discharge link each catch to verified origin data
- Regulatory compliance verification – Automated checking against 15+ databases including RFMO registries and IUU blacklists
- Sustainability certification integration – Seamless compatibility with MSC CoC and ISSF PVR systems
- Comprehensive documentation – Digital storage of vessel records, discharge volumes, and certification documents for audit-ready traceability
Built on GS1-EPCIS standards and fully GDST compatible, SmarTuna enables seamless data exchange throughout the tuna supply chain. This first-mile traceability approach reduces regulatory risks and supports premium market positioning for responsibly caught tuna.
Discover how SmarTuna transforms tuna supply chain transparency with comprehensive vessel-to-shelf traceability for your purse seine fishing operations.
