Catch-and-Release Mortality of Spotted Seatrout in Texas

—Catch and release is becoming more common as a management tool in marine recreational fisheries. Clearly, a critical factor in determining different management scenarios that use this strategy is postcapture survival. We investigated the mortality associated with catch and release in the fishery for spotted seatrout Cynoscion nebulosus in south Texas. Specifically, this study investigated the mortality for hook-andline-captured spotted seatrout as a function of bait type, hook type, angler skill level, and fish size. Using a variety of angling techniques, we captured 448 spotted seatrout ranging from 250 to 760 mm total length (TL) and assessed mortality in replicate field enclosures. The overall short-term mortality for all treatments was relatively low (11%); the majority of fish survived. The exception was angler skill level. Angling by novices produced a significantly higher mortality rate than angling by skilled anglers; however, mortality averaged only 18% even for inexperienced anglers. To evaluate long-term mortality, we monitored 27 spotted seatrout held in a laboratory facility for 30 d; the fish showed no signs of long-term mortality. We observed 11% mortality during the first 48 h and no mortality during the subsequent 28 d. In an attempt to increase the abundance of ‘‘trophy’’ (.635 mm TL) spotted seatrout, Texas has adopted new slot limit regulations that allow only one trophy-size fish to be kept per person per day. We targeted larger (635–736 mm TL) fish to assess the mortality associated with this size-group. Regression analysis showed no size-related mortality. The location of hook-related injuries may be the most important factor in determining catch-and-release mortality. Anatomical hooking location was not a factor in the analyses but was treated as a component of experimental treatment level; however, we observed that mortality was typically associated with hooking location rather than angling method or bait type. These data suggest that management options involving the release of spotted seatrout, including those larger than 635 mm TL, are viable tools. Growing competition in our marine fishery resources has led fisheries managers to consider a number of management alternatives. Catch and release, a widely used management tool in freshwater systems, is becoming more accepted in marine recreational fisheries (Muoneke and Childress 1994). Clearly, a critical factor in determining the success of size-related management strategies (e.g., slot limits) is postcapture survival. Despite the rapid integration of catch and release into many marine fish management programs, the data available to predict the success of such regulations are often limited (Matlock 2002). The spotted seatrout Cynoscion nebulosus is one of the most sought-after recreational fishes landed in the southeastern USA. In the Gulf of Mexico, approximately 3.3 million anglers spent 23 million days fishing in 2003 and the most commonly captured species was the spotted seatrout (Van Voorhees and Pritchard 2004). Texas has an abundant spotted seatrout population: 1,000,000 individuals are harvested annually (Green and Campbell 2005). A long-term monitoring program (1982–2000) conducted by the Texas Parks and Wildlife Department (TPWD) suggests that the abundance and spawning biomass of spotted seatrout are at an all-time high (MartinezAndrade et al. 2005). Despite the apparent health of the spotted seatrout population, managers are concerned over decreasing availability of spotted seatrout larger than 635 mm total length (TL). Texas has regulated the spotted seatrout fishery since 1978 using lower length limits (Hegen et al. 1987). From 1990 to 2003, the minimum size limit was 381 mm TL (Blanchet et al. 2001). In response to recent declines in the availability of trophy-size spotted seatrout (.635 mm or 25 in TL), the TPWD instated a somewhat controversial slot limit regulation. The lower size limit of 381 mm TL was retained, but an upper slot of 635 mm TL was added. Anglers are currently allowed to retain only one trophy-size fish per person per day. Controversy surrounding this regulation has arisen from anecdotal information supplied by recreational anglers, indicating that spotted seatrout exceeding the upper limit did not survive after release. There have been few studies on catch-and-release mortality of inshore recreational fisheries (see review by Muoneke and Childress 1994), and the literature is inconclusive about the spotted seatrout mortality (0– 70%) elicited by this management method (Murphy et al. 1995; Duffy 2002). The new spotted seatrout * Corresponding author: [email protected] Received October 25, 2005; accepted March 17, 2006 Published online November 6, 2006 843 North American Journal of Fisheries Management 26:843–848, 2006 Copyright by the American Fisheries Society 2006 DOI: 10.1577/M05-181.1 [Article]