Roles of Sea Turtles in Marine Ecosystems: Reconstructing the Past
Populations of sea turtles have been drastically reduced since interactions between humans and sea turtles began. Although Caribbean sea turtle populations generally have been considered to be pristine when Columbus arrived in 1492, archeological research is now revealing that some sea turtle nesting aggregations in the Caribbean were extirpated or significantly reduced by Amerindians (Carlson, 1999; O’Day, 2001). Therefore, the roles that sea turtles played in the functioning of ecosystems in the Caribbean may have been substantially affected before European contact. Initially a result of directed harvest, population declines have more recently been driven by factors in addition to direct harvest, such as incidental capture in commercial fisheries, habitat degradation, introduction of feral predators on nesting beaches, and marine pollution (Eckert, 1995; Lutcavage et al., 1997; Witherington, in press). These population declines have produced a corresponding decline in the extent to which sea turtles fulfill their roles in maintaining the structure and function of marine ecosystems.