Genome-wide DNA reveals genetic provenance and intra-familial migratory site fidelity in Common Redshanks
We investigated the genetic provenance and population genetic trajectory of a wintering population of Common Redshanks (Tringa totanus) in Southeast Asia. Using over 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 of historic and contemporary migratory connectivity with breeding populations in the Qinghai-Tibetan Plateau. Our population genetic analyses revealed that Singapore's Common Redshanks have harboured persistently low levels of genetic diversity throughout the temporal sampling regime. We also demonstrate, for the first time in shorebirds, evidence for migratory site fidelity within closely-related familial pairs across multiple seasons. Our findings are consistent with population genetic stability and past findings on the species' exceptional site fidelity, results which are reassuring for the population's conservation status and shed insights into potential vulnerabilities and conservation 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. We recommend future studies to expand the current sampling regime to achieve a comprehensive phylogeographic overview for further insights into the genetic and migratory connectivity of the species.