This study will use molecular markers to address a question about migration patterns in the in the Giant Amazon River Turtle of South America. These turtles are colony nesters (adult females emerge simultaneously to nest on specific beaches), and limited evidence suggests that females show high "homing" fidelity to the same beach each year. The goal of this project is to use molecular genetic markers to test the "natal homing" question, because it leads to unambiguous expectations about the distribution of genetic variability within and between river basins. River basins will be sampled throughout Brazil's portion of the Amazon watershed.
The intrinsic interest of this work derives from its application of new models gene flow to a widespread species whose migration routes constrained to a "rectilinear" grid (the rivers), but it will also have practical implications for ongoing conservation programs in Brazil. The government monitors and protects many of the most heavily used beaches, but management plans are not based on any knowledge of the genetic uniqueness of any of the populations. Further, the funds available for training of Brazilian investigators will enhance their understanding of the connection between the use of molecular genetic markers and applied ecological issues.
