Catch and Release in Marine Recreational Fisheries

<em> Abstract.</em>—One component of the management regimen employed to rebuild the Atlantic coastal migratory stock of striped bass <em> Morone saxatilis </em>was the imposition of large size limits to reduce fishing mortality to zero, on the 1982 and subsequent year-classes, until 95% of the females had an opportunity to reproduce at least once. Such size limits introduce size-selective mortality that favors the survival of slower-growing members of the population and may select for slower growth in succeeding generations. Size-at-age data from the Hudson River population were used to examine the effect of alternative size limits on the length distributions of survivors by age using simulation. The results indicate that minimum sizes currently in use can cause profound changes in the size composition of the spawning stock. The mean asymptotic length of unfertilized eggs under equilibrium conditions was estimated as an index of the extent to which these changes may influence future growth. With the current best estimates of growth parameters and fecundity at size, this index was reduced by only about 3%. However, because of the size-selective mortality in the existing fishery and uncertainty arising from sampling difficulties, growth is probably poorly characterized by the existing data. Sensitivity analyses revealed that some reasonable combinations of growth and minimum sizes can induce changes in the mean asymptotic length of unfertilized eggs by more than 10%, which would be about 30% in terms of asymptotic mean weight. The extent to which this selective force might be expressed in succeeding generations is uncertain. However, reliance on minimum sizes to constrain catch has the potential to cause profound changes in growth and probably should not be adopted for long-term management of striped bass until this problem is better understood.

Catch and Release in Marine Recreational Fisheries

<em>Abstract.</em>—The Cooperative Tagging Center (CTC) of the National Marine Fisheries Service’s Southeast Fisheries Science Center operates one of the largest and oldest fish tagging programs of its type in the world. Since 1954, more than 35,000 recreational and commercial fishing constituents have voluntarily participated in the CTC, and this has resulted in tagging more than 245,000 fish of 123 species. Although some tagging activities have been conducted by scientists, most of the tag release and recovery activities were achieved by recreational and commercial fishery constituents. Five large highly migratory species have historically represented the Program’s primary target species, including Atlantic bluefin tuna <em> Thunnus thynnus</em>, blue marlin <em> Makaira nigricans</em>, white marlin <em> Tetrapturus albidus</em>, sailfish <em> Istiophorus platypterus</em>, and broadbill swordfish <em> Xiphias gladius</em>. Tagging equipment and procedures for catching, tagging, and resuscitation of species too large to be brought aboard fishing vessels have evolved and improved considerably over the years. This paper presents a review of the development of the most efficient tagging, handling, and dehooking techniques used on a variety of large, highly migratory species in the CTC. In addition, the results of a comparative tag retention study on billfish are presented, comparing stainless steel dart tags used for nearly 30 years with a hydroscopic nylon double-barb dart tag, recently developed in conjunction with The Billfish Foundation. Recommendations are made on the best techniques, procedures, and equipment for in-water tagging of large, highly migratory species.