Genome-wide DNA reveals decades-long genetic stability and intra-familial migratory site fidelity in an Asian population of Common Redshanks

We investigated the population genetic trajectory and genetic diversity of a wintering population of Common Redshanks (Tringa totanus) in Southeast Asia. Using ~ 23,000 genome-wide single nucleotide polymorphisms (SNPs) harvested by double-digest restriction-site associated DNA sequencing (ddRADseq) of Common Redshanks collected in Singapore across 28 years, we uncovered evidence for long-term genetic homogeneity that points to sustained migratory connectivity of individuals found in Singapore. Our population genetic analyses also revealed that Singapore’s Common Redshanks have harboured persistently low levels of genetic diversity throughout the temporal sampling regime. We further furnish, for the first time in shorebirds, genomic evidence for migratory site fidelity within closely related familial pairs across multiple seasons. Our findings are consistent with population genetic stability and support past results on the species’ exceptional site fidelity, with ramifications for the population’s conservation status and management strategy. Our work highlights the utility of genome-wide DNA techniques in combination with robust longitudinal sampling regimes for effective genetic monitoring programs targeted at highly mobile avian taxa, with broad applicability and relevance to highly dispersive taxa in general. We recommend that future studies expand the current sampling regime to achieve a comprehensive phylogeographic overview for insights into the genetic and migratory connectivity of the species.