FAD Structure Impacts
Purse Seine Guidebook
- Table of Contents
- Chapter 1
- Chapter 2
- Chapter 3
- Introduction
- Avoid Bycatch
- Minimize the Risk of Capture
- Reduce Bycatch Mortality
- Offset Unavoidable Bycatch Mortality
- 1. Sharks and Rays
- Sharks and Rays Commonly Encountered
- Reducing Shark and Ray Bycatch
- Target Large Schools
- Attract Sharks Out of the Net
- Fish Sharks in the Net to Release Them
- Modify Fishing Gear
- On Deck Safe Handling and Releasing Techniques
- Manual Handling Do’s
- Handling Medium Sharks
- Handling Stingrays
- Handling and Release with Bycatch Release Devices
- Light Equipment
- Shark Release Ramps with Hopper
- Mobulid Sorting Grids (with Vessel’s Crane)
- Releasing Whale Sharks
- Shark Handling and Release Do’s
- Shark Handling and Release Don’ts
- End Wasteful Shark Finning
- 2. Sea Turtles
- Most Common Bycaught Sea Turtle Species
- 3. Selective Tuna Fishing: Reducing Catch of Small Bigeye & Yellowfin Tuna
- Species Identification
- Yellowfin (30-45 cm)
- Bigeye (30-45cm)
- Yellowfin (46-110cm)
- Bigeye (46-110 cm)
- Yellowfin (>110 cm)
- Bigeye (>110 cm)
- Fisher Cooperation and Input
- Chapter 4
- Introduction
- International Organizations and Instruments
- Inter-American Tropical Tuna Commission
- Western and Central Pacific Fisheries Commission
- International Commission for the Conservation of Atlantic Tunas
- Indian Ocean Tuna Commission
- Commission for the Conservation of Southern Bluefin Tuna
- Further Notes on Data Reporting and Compliance
- Conclusion
- Credits and Citations
Drifting Fish Aggregating Devices (dFADs), which consist of a surface or subsurface raft and a submerged appendage, are most often made of plastic materials such as nylon canvas, plastic buoys, and polypropylene ropes.
The submerged appendages are typically composed of different material, including netting until recently, and can reach depths of up to 50 meters for some fleets operating in the Pacific Ocean. It was estimated that approximately 100,000 dFADs were deployed annually by fleets operating in the Indian, Atlantic, and Pacific Oceans (Gershman et al. 2015). The impacts of dFADs can be categorized into two major components:
- Ghost fishing due to entanglement (Filmalter et al. 2013) when FADs are constructed with surplus purse-seine netting, as was common in the fishery until recently
- Marine debris, including the accumulation of plastic at sea when dFADs are lost or abandoned, as well as their impacts on coastal habitats when stranded ashore