Origin of the Red‐veined Darter dragonflies migrating into the European part of Russia revealed by stable isotopes of hydrogen

Dragonflies are well‐known migratory insects, and stable isotopes have been used successfully to study their migrations in America and Asia but less so in Europe. Here we used the isotopic composition of hydrogen (δ2H value) in metabolically inert wing tissues of the dragonfly Sympetrum fonscolombii (Selys, 1840) to investigate migration patterns and likely origin of immigrants into the European part of Russia. During spring–summer, sexually mature dragonflies arrive to Russia for reproduction and individuals of the summer generation (descendants of immigrants) presumably migrate in the opposite direction in the fall. Analyses included 39 specimens of immigrant S. fonscolombii dragonflies, 11 specimens from 3 species of resident dragonflies (including S. fonscolombii) from the European part of Russia and 16 specimens representing 9 resident dragonfly species from Iran. The average δ2H values of the wings of immigrant S. fonscolombii (−71.9 ± 23.4‰) were significantly higher than those of resident dragonflies in European Russia (−121.7 ± 9.5‰) and similar to those of resident dragonfly species from Iran (−72.3 ± 18.4‰). Based on a geostatistical model of the global δ2H values in precipitation, and considering the distribution of S. fonscolombii, the most probable natal area of immigrants arriving in European Russia is located in Southwest Asia. The suggested migration zone covers regions located between approximately 26°–28° N in the south and 56°–58° N in the north, while the migration distance can reach 2000–4000 km.