M.Sc. Thesis, Graduate Program in Ocean Sciences and Limnology, National Autonomous University of Mexico (UNAM)
DIACHRONIC ANALYSIS OF THE EXPLOITATION, ABUNDANCE, AND SIZE OF CHELONIA MYDAS IN THE CENTRAL BAJA CALIFORNIA PENINSULA, 12,000 B.P.-2012.
Environmental history is valuable for assessing long-term baselines, which are highly relevant and applicable in conservation and management. Through the analysis of ethnographic, historica (18th-20th Century), and archaeological (12,000 B.P.-18th Century) data, I reconstructed fishing efforts and captures of the East Pacific green turtle, Chelonia mydas, over a broad time scale. Despite the fact that sea turtles have been an important food source for human populations in the peninsula for over 6,000 years and were the target of a large-scale commercial fishery during much of the 20th Century, little is known about their past abundance. Therefor, it is difficult to assess their decline or recovery. In order to reconstruct past human-sea turtle interactions, I compiled historical information which includes missionary reports, diaries of pirates and whalers, and scientific reports, among others. I also interviewed sea turtle fishermen (caguameros), cowboys, truckers, scientists, and divers in two communities in the central peninsula: Bahía de los Ángeles, B.C., and Guerrero Negro, B.C.S. Both towns were centers of an important commercial sea turtle fishery that operated during the second half of the 20th Century until a total ban was declared in 1990. Through the use of statistics and mathematical modelling, I reconstructed fishing patterns and sea turtle consumption from the late prehispanic occupation until the late 20th Century, and compared them with monitoring data obtained in both communities between 2001 and 2012.