Analysis of the Population Structure of Broad-snouted Caiman (Caiman Latirostris) in Santa Fe, Argentina, Using the Rapd Technique

Abstract

Caiman latirostris (Broad-Snouted Caiman) is one of two crocodilian species that inhabit Argentina. Wild populations of C. latirostris in Santa Fe Province are under management by Proyecto Yacaré (MAGIC-MUPCN), a program based on a ranching system whose goal is the sustainable use of the species, together with its habitat conservation. We used 233 random amplified polymorphic DNA (RAPD) markers to obtain preliminary data about population structure and genetic variation in four populations of C. latirostris in Santa Fe province, which may be used to provide a genetic framework of conservation units to evaluate, and perhaps to modify, current plans for its sustainable management. Our results suggest low to intermediate levels of mean heterozygosity (H), mean number of alleles per locus (A), and percentage of loci polymorphic (P). Furthermore, the values of Nm and FST seem to show low levels of gene flow and some population subdivision. Distance genetic analysis appears to reveal high similarity between Estancia El Estero, Costa del Salado, and Estero del Paraje 114 populations, and results of analysis of molecular variance indicate that nearly all variation exists within populations rather than among them, implying that a great number of alleles is shared among populations. New samplings and new measurements in parameters such as H, A, and P, should be carried out in future years to confirm the genetic structure and level of population differentiation and to make new decisions about the management plan that has been successful in the recovery and conservation of C. latirostris.