This project seeks to evaluate franciscana dolphin population structure and stock identity along the species distribution range, with a focus on its southernmost portion located off the coast of northern Argentina. Furthermore, we are interested in identifying those environmental features that may be, at least in part, responsible for coastal cetacean population structure. Our analysis uses cutting-edge genetic tools, which allow an unparalleled level of accuracy on population identification and gene flow estimation. In order to assess both maternal and bi-parental lineage structure, such tools are used on a combination of nuclear and mitochondrial DNA. This genetic information is evaluated in an explicit environmental framework, taking into account a suite of oceanographic and ecological features.
        Our results to date support the previous proposition of two franciscana populations in Brazil, and further suggest the existence of at least two previously unidentified populations in Argentina, to the south of the La Plata River estuary. Contrary to what is common for many cetacean species, franciscana population structure does not respond to a pattern of isolation by distance, by which the further apart populations are, the greater their genetic isolation. Rather, abrupt breaks in oceanographic conditions seem to play a major role on the genetic structure patterns of this species.
        Understanding population structure patterns is key for conservation strategies, as it aids in the identification of important areas to preserve demographically independent groups of individuals or populations. In fact, effective management strategies require the identification of such populations and population areas. Further, by adding the environmental dimension, we will be able to gain a better understanding of how the environment influences the structure of franciscana populations, and hence how potential environmental changes may impact such structure.
        This work would not be possible without the invaluable support of the entire Fundacion Aquamarina staff and volunteers, or without the collaboration of the local wildlife authorities. Funding for this project comes from Wildlife Trust and the Cetacean Conservation and Research Program at WCS and the AMNH.