Cristopher Giovanny Avalos Castillo
This project will provide up to date scientific information of sharks and rays captured by fishermen at the Pacific coast of Guatemala. In general this project will provide biologic information: abundance and diversity of species, size composition, sex ratio for main species captured and determine possible spatial-temporal variations. Additionally we will estimate the catch per unit effort for each species as well as for the main fishing gear used to capture elasmobranchs in the study area, for both directed and incidental fisheries. Finally, we will evaluate the presence of neonates and juvenile organism of sharks and rays, indicating possible nursery areas on the continental shelf of the country.
Providing scientific information of the sharks and rays captured, the fishing effort, as well as information of its biology and location of nursery areas, will be an important step toward proposing recommendations towards possible management plans in the area, currently lacking. Having up-to date scientific information on elasmobranch species, its size composition and the fishery in the area are aspects necessary for proposing management actions, actions that may guarantee the recruitment of different elasmobranch species present in the area, which finally aims to help to maintain elasmobranch populations healthy and maintain people's livelihood
Sharks are vulnerable and susceptible to overfishing because they are characterized by low reproductive potential, have long gestation periods and slow growth, and require a long period to reach sexual maturity (Walker, 1992; Castro, 1993). Fishery biologists consider a stock, or population of a species, unsustainable when the rate of exploitation by fishermen reduces their recruitment, or abundance, to a level at which the catch rate cannot be sustained annually (Klimley, 2013).
In the Pacific of Guatemala, five species are identified as the main catches by the fishing fleet: Carcharhinus falciformis, Nasolamia velox, Carcharhinus limbatus, Sphyrna lewini and Alopias pelagicus (FAO, 1999). Of these species, C. falciformis, Alopias pelagicus and S. lewini are listed in CITES appendix II. This list include species that are not necessarily now threatened to extinction but may become so unless trade is closely monitored and controlled.
Previous research in the Pacific of Guatemala conducted by Márquez and Ruiz (1999) highlight the high incidence of juvenile and neonatal organisms of sharks and rays in the fishing catches, recommending future research efforts to search and locate sharks and rays possible nursery areas.
Providing up to date scientific information of elasmobranchs captured in the Pacific of Guatemala, as well as different aspects of their biology and the existence of nursery areas of sharks and rays may allow the creation of a protection plans to maintain the continuity of recruitment of the various species of elasmobranchs, which aims to helps maintain elasmobranch populations healthy and maintain people's livelihood.
This project will also generate information necessary for the country to contribute to global protection for sharks that were included in the list of endangered species of wild fauna and flora (CITES). In the case of Guatemala one of the most commonly species caught by the fishery fleet are
C. falciformis and S. lewini, both included in appendix II of CITES. It is necessary to contribute with the national guidelines to regulate its commercialization.