During the 2017/2018 school year, three high school students participated in a nationally funded program to characterize the diversity and density of fish species in Punta Chame Bay, Panama. Temporal data will quantify the importance of this region as a nursery for juvenile and neonate sharks. Sharks in Punta Chame Bay have experienced a precipitous decline (75% over the last ten years) due to artisenal fishing practices. By quantifying the importance of this bay as a nursery, and informing fisherman of the costs of their fishing practices to local shark populations, we hope to establish a minimum catch size and institute seasonal fishing restrictions to better protect the shark population. Students participated in monthly sampling trips where they learned to identify and measure potential prey species and tag neonate sharks as part of a mark-recapture program to quantify current populations and estimate mortality due to fishing. Students experienced the cost of science via shark mortality as we characterized the bay, and they were able to reflect on the process of science as sampling parameters and techniques evolved in response to low catch rates, variability in water temperature and pH, and disappointing results from sediment collected for analysis.
Results/Conclusions
Monthly gill netting was conducted in various locations throughout the bay. All catch were identified to species, measured, and released. Any sharks caught were tagged prior to release. The lead scientiest, Dr. Yehudi Rodriquez from Ramsar Regional Center for the Western Hemisphere explained the purpose of the study to local fishermen and asked them to report any marked or unmarked sharks caught during the course of their fishing excursions. Catch rates declined from a high of 604 representing 39 species in the wet season to a low of 106 representing 28 species in the dry season. Dry season ocean temperatures and pH were lower with offshore wind creating localized upwelling events. While the species remained similar across the months, the community structure changed in terms of species dominance and abundance. Shark capture rates were the highest in the months with the greatest fish diversity but not density. Currently, at the midpoint of the project, there are 45 neonates and juveniles tagged and two fishermen have reported catching previously tagged sharks. The students participated in all aspects of the work, and were able to experience the process of science as the parameters of the study shifted to accommodate unexpected results.