Landscape genetics of two declining North American aerial insectivores

Abstract

I used molecular markers to examine the population genetic structure of two declining North American aerial insectivores; barn swallows and bank swallows. Both species are long-distance migrants and have a wide distribution. The findings revealed similar overall genetic clusters corresponding to western, central and eastern regions of North America. Strong population differentiation of the eastern population in both species was observed making this population a priority for conservation, especially given the large decline in the region. The results provide evidence that both species inhabited multiple refugia during the Pleistocene and interplay between migratory pathways and geographical barriers also play an important role in shaping genetic differences between populations. This study provides insights into selecting appropriate genetic techniques in future studies of migratory species and assists with developing conservation strategies.