Summary
The Patagonian toothfish longline fishery in the Southwest Atlantic suffers from depredation of fish by sperm whales and high bycatch rates of seabirds. This study assessed depredation and seabird bycatch using a modified longline with an "umbrella" net sleeve system with stones for faster sinking. The "umbrella-and-stones" system was effective for preventing bycatch and appeared to restrict depredation, but catches were significantly reduced.