South African Tursiops aduncus ddRAD genepop file

Many marine species exhibit fine-scale population structure despite high
mobility and a lack of physical barriers to dispersal, but the
evolutionary drivers of differentiation in these systems are generally
poorly understood. Here we investigate the potential role of habitat
transitions and seasonal prey distributions on the evolution of population
structure in the Indo-Pacific bottlenose dolphin, Tursiops aduncus, off
South Africa’s coast, using double-digest Restriction-site Associated DNA
sequencing (ddRADseq). Population structure was identified between the
eastern and southern coasts and correlated with the habitat transition
between the temperate Agulhas (southern) and subtropical Natal (eastern)
Bioregions, suggesting differentiation driven by resource specialisations.
Differentiation along the Natal coast was comparatively weak, but evident
in some analyses and varied depending on whether the samples were
collected during or outside the seasonal sardine (Sardinops sagax) run.
This local abundance of prey could influence the ranging patterns and
apparent genetic structure of T. aduncus. These findings have significant
and transferable management implications, most importantly in terms of
differentiating populations inhabiting distinct Bioregions and seasonal
structural patterns within a region associated with the movement of prey
resources.