國後島
Riga Zoo researchers have participated in various entomology expeditions since 1989. In 1989-1993 expeditions were made to various places in the former Soviet Union (Ukraine, Central Asia, Azerbaijan, Southern Siberia, Primorsk, Sakhalin and Kunashir Island). Since 1994, Riga Zoo has participated in six expeditions to Vietnam, where ten new species have been found during these expeditions.