Optimization of Hook Size to Reduce Discards and Injury in the New Jersey Summer Flounder Hook-and-Line Fishery

Catch-and-release angling introduces potential mortality in discarded fish, yet their survival is essential for maintaining fish stocks. Regulation of hook size in the hook-and-line fishery for Summer Flounder Paralichthys dentatus can reduce the number of discards as well as hook injury associated with catch and release. The objective of this study was to determine the effects of different J-hooks on discards and the effect of hook set location in Summer Flounder. We evaluated the influence of eight different-sized J-hooks (2/0-9/0) on Summer Flounder (N=7,764) catch composition in coastal NewJersey during the spring and summer of 2014. Fish TL and thehook location were recorded for each Summer Flounder. Hookset locations included lip, mouth, eye, gill, gut, and externalfoul (i.e.,viscera or muscle). Larger J-hooks (6/0-9/0) caught larger fish (381-406mm TL) than 2/0-5/0 hooks (365-381mm TL). In addition, larger J-hooks (6/0-9/0) decreased the total number of fish caught and the number of discards, with no reductions in legal-sized fish caught compared to smaller hooks (2/0-5/0). The majority of fish were hooked either in the lip or in the mouth. Larger hooks decreased hooking in the gut and increased external foul hooking compared to smaller hooks. We conclude that larger J-hooks outperform smaller hooks by catching larger fish, reducing the number of discarded fish, and reducing the incidence of fish hooked in the gut. Therefore, the use of larger hooks has the potential to reduce discards and the discard mortality rate related to catch and release in the Summer Flounder hook-and-line fishery.