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The fishery for Panulirus argus (Latreille, 1804) in The Bahamas, which is the largest in the Wider Caribbean Sea, was historically trap-based, but casitas surpassed traps as the primary fishing gear in the 1990s. Casitas are artificial shelters that aggregate lobsters for ease of capture, but they are unregulated in The Bahamas and their effects on fishery sustainability are unknown. Concerns about whether overcrowding of lobsters within casitas detrimentally alters lobster growth, disease, or mortality prompted our study. Tethering and videography were used to compare lobster mortality and predation risk at casitas and in the natural environment, whereas nutritional condition, growth, injury, and prevalence of disease were compared for lobsters within casitas and traps. We found no difference in predation on subadult or adult lobsters in casitas compared to natural areas, although predators were more abundant near casitas. Lobsters in casitas had higher blood protein indices and fewer had shell disease than those in traps; the PaV1 virus was absent from lobsters we sampled. Starvation experiments in which lobsters were held in "ghost" traps during the closed season revealed a significant decline in lobster nutritional condition and an increase in shell disease after 3 wks, with nearly all lobsters afflicted after 6–12 wks. In summary, we found no evidence that casitas negatively affect subadult and adult P. argus in The Bahamas. Juvenile lobsters were rare in our study so potential effects of casitas on them were not investigated. Traps, however, pose a risk to the fishery if not properly managed.

The pathogenic virus Panulirus argus virus 1 (PaV1) was first discovered in Caribbean spiny lobsters Panulirus argus from the Florida Keys (USA) in 1999 and has since been reported in Belize, Mexico, and Cuba; its distribution in the wider Caribbean is unknown. We col- lected tissue samples from adult spiny lobsters from 30 locations in 14 countries bordering the Caribbean Sea and used molecular diagnostics to assay for the presence of PaV1. PaV1 occurred primarily in the northern areas of the Caribbean, where its prevalence was highest. The virus was not found in lobsters from the southeastern Caribbean, and its prevalence was lowest in the south- western Caribbean. DNA sequence analysis was performed on a fragment of the viral DNA to examine the genetic diversity of PaV1 on a Caribbean-wide scale. Sequence variation in the viral DNA fragment was high, with 61 unique alleles identified from 9 areas. The sharing of viral alleles in lobsters from distant locations supports the hypothesis of a strong genetic connectivity among lobsters within the Caribbean, and further supports the hypothesis that postlarvae infected with PaV1 may serve to disperse the virus over long distances.