Genetic diversity and population structure of the franciscana dolphin, Pontoporia blainvillei, in Southern Buenos Aires, Argentina

Abstract

The franciscana dolphin, Pontoporia blainvillei, is endemic to thecoastal waters of the southwestern Atlantic Ocean and the mostendangered dolphin in the area. Four Franciscana ManagementAreas (FMAs) are currently recognised; however, results of geneticstudies suggest the requirement for additional FMAs and highlightthe need for more detailed studies in the southern extreme of thespecies distribution. With this aim, we studied the genetic diversityand population structure of the species analysing an mtDNAcontrol region fragment (434 bp) in 44 individuals collected in foursampling sites located in Southern Buenos Aires. Haplotypediversity (H = 0.75 ± 0.05) was mostly higher than the observed inendangered or near threatened odontocetes. Population structureanalyses suggest that three different genetic populations should berecognised within FMA IV: Northern, Eastern and Southern BuenosAires. Altogether, these results should be taken into account infuture conservation plans for the species.