Survival probability estimates for large juvenile and adult green turtles (Chelonia mydas) exposed to an artisanal marine turtle fishery in the western Caribbean

The largest remaining green turtle (Chelonia mydas) population in the Atlantic is potentially threatened by the resurgence of a commercial artisanal green turtle fishery in Nicaragua. Nicaragua is the site of the principal feeding ground for adults from the Tortuguero, Costa Rica, rookery. Little is known about the life history parameters of this population away from the nesting beach. To better understand the potential impact of harvesting in Nicaragua on the Tortuguero population, we estimated survival rates of adult females tagged on the nesting beach at Tortuguero, and a mixed group of large juveniles and adults tagged at turtle fishing sites in Nicaragua. Based on band recovery analysis, large juvenile and adult green turtles tagged at Nicaragua turtle fishing sites have a very low annual survival probability, 0.55. Adult females tagged on the nesting beach, which may forage at a broad range of Caribbean feeding grounds, had an annual survival probability of 0.82. These survival rate estimates are likely too low to sustain the population and have important implications for the future of the Tortuguero rookery.