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Escape gaps are a tool commonly used to reduce the catch of sublegal-size animals and bycatch in crustacean trap fisheries. In Florida's Caribbean spiny lobster (Panulirus argus) commercial trap fishery, traps are baited with live, sublegal-size lobsters, which precludes the use of escape gaps sized to exclude capture of undersize lobsters. Both wood and wire traps are used in the fishery, but wire traps capture more fish as bycatch than do wood traps. This project was developed and executed cooperatively with commercial fishers to evaluate, for wire lobster traps, the effect of escape gaps on catch rates of bycatch and harvestable lobsters. We tested five wire-trap configurations that included a control trap without escape gaps (i.e., an unmodified commercial trap) and four configurations consisting of a narrow (3.81 cm) or wide (5.40 cm) escape gap, oriented either vertically or horizontally. All traps were fished in the Atlantic Ocean at a deepwater site (ca. 30 m) and a shallow-water (ca. 10 m) site. Control traps and traps with a narrow escape-gap configuration were baited with a live, sublegal-size lobster; traps with a wide escape-gap configuration were baited with a live, legal-size lobster. We compared the number of lobsters caught and coral reef fish bycatch, as well as size frequency distributions of lobster and compressiform fish species, which include fish in the snapper and grouper families, in each trap configuration. Escape-gap traps caught statistically similar numbers of legal-size lobsters in all configurations except the wide horizontal configuration at the deep site. The catch of sublegal-size lobsters was significantly reduced in the wide horizontal and wide vertical escape-gap trap configurations at both sites. Fish bycatch was dominated by compressiform fish of the Haemulidae family and fish bycatch was significantly reduced in all escape-gap trap configurations. Our results suggest that the wide vertical escape-gap configuration maximized both the retention of harvestable lobsters and the escape of sublegal-size lobsters and fish bycatch. Inclusion of any of the escape-gap configurations tested could reduce discard mortality of fish and undersize lobsters, but baiting and trap fishing methods may need to be adjusted to maximize lobster harvest. • Escape-gap traps can maintain legal-size lobster catch while reducing fish bycatch. • Fish bycatch was significantly reduced in all escape-gap configurations. • Wide escape-gap configurations significantly reduced sublegal-size lobster catch. • Fish bycatch was dominated by Haemulida e and Ostraciidae. [ABSTRACT FROM AUTHOR]

Ghost fishing is the capacity of lost traps to continue to catch and kill animals. In the spiny lobster (Panulirus argus) fishery in Florida, the effects of ghost fishing are of particular concern, given the estimated 10s of 1000s of traps lost annually. We distributed 40 each of the three types of lobster traps (wire, wood–wire hybrid, and wood slat) at three locations in the Florida Keys to simulate ghost fishing. Divers monitored these traps biweekly for 1 year then monthly for two additional years, recording the time ghost traps remained intact and continued to fish, as well as the number of live and dead lobsters and other animals in each trap. Wood slat and hybrid traps remained intact and fished for 509 ± 97 (median ± median absolute deviation) and 480 ± 142 d, respectively. Wire traps fished significantly longer (779.5 ± 273.5 d, p < 0.001), and several fished until the end of the experiment (1071 d). Traps in Florida Bay fished longer (711.5 ± 51.5 d) than traps inshore (509 ± 94.5 d) and offshore (381 ± 171 days; p < 0.001) in the Atlantic Ocean. More lobsters were observed in hybrid traps (mean = 4.81 ± 0.03 s.e.) than in wood slat (3.85 ± 0.16) or wire traps (3.17 ± 0.03; F = 40.15, d.f. = 2, p < 0.001). Wire traps accounted for 83% of fish confined overall and 74% of the dead fish observed in traps. Ghost traps in Florida Bay and Atlantic inshore killed 6.8 ± 1.0 and 6.3 ± 0.88 lobsters per trap annually, while Atlantic offshore traps killed fewer (3.0 ± 0.69) lobsters, likely as a result of lower lobster abundance in traps. The combined effects of greater lobster mortality and greater abundance of lost traps in inshore areas account for the majority of the estimated 637 622 ± 74 367 (mean ± s.d.) lobsters that die in ghost traps annually. [ABSTRACT FROM AUTHOR]