Stable carbon and nitrogen isotope data for Siberian barn swallow subspecies collected during the breeding season
This dataset includes stable carbon and nitrogen isotope values for the inner tail retrices of three subspecies of barn swallow (Hirundo rustica rustica, H. r. tytleri, and H. r. gutturalis).  Sampling was conducted in Russia (summer 2013), China (summer 2014), Mongolia (summer 2014), Japan (summer 2014), and western …