Investigation of population trends and evolutionary history of the SAi using genomic techniques to provide comprehensive findings on the Bryde’s whale (Balaenoptera edeni brydei)

Abstract

The dataset consists of the microsatellite data. The Bryde’s whale (Balaenoptera edeni) is characterised by a complex history of discovery, a currently unresolved taxonomy, and the occurrence of several discrete populations throughout its global distribution. These factors hinder the accuracy of conservation assessments and complicate the delineation of conservation units as well as recognised subspecies and species listings. In order to address these challenges, targeted research efforts are required into discrete Bryde’s whale populations to generate population-level information that can be used to inform the delineation of conservation units and broader taxonomic clarification. The South African inshore Bryde’s whale population (SAi) is one of these discrete populations with a restricted distribution to the country’s coastline. The study investigated the population trends and evolutionary history of the SAi using genomic techniques to provide comprehensive findings on these aspects. Mitochondrial genome data indicate that the SAi forms a unique genetic lineage, most similar to the Bryde’s whale subspecies Balaenoptera edeni brydei. Whole-genome analyses of phylogenetic relationships and differentiation tests show that SAi is genetically more distant from Eden’s whale (B. edeni edeni) than from Rice’s whale (B. ricei) and distinct from other Bryde’s whale populations in the southeast Atlantic (SEA) and northern Indian Oceans. This research emphasises the importance of targeted research into disparate Bryde’s whale populations which is essential in uncovering cryptic genetic diversity significant for conservation efforts regarding preservation and prioritisation.