Previously found in freshwater springs of hypersaline littoral Lake Techirghiol (south of Constanta). Has been extinct due to the hybridization with Gasterosteus aculeatus. Springs inhabited by Gasterosteus crenobiontus were previously separated from habitat of Gasterosteus aculeatus by a hypersaline lake that served as a barrier between the species. Irrigation activities transformed the lake into a brackish one which was invaded by migratory Gasterosteus aculeatus (Ref. 59043).

Status of threat: extinct (Ref. 59043).