Mass migration of crabs has hit the waters of Primorye Region. Although not quite an unusual event, this year's migration startles both fishers and ecologists with the sheer number of crabs. Fishers unwillingly catch them, although crab hunting is banned in Primorye waters.

      No exact reason for such movement has yet been found. It is possible that crabs have been set free by poachers, but the cause of migration may lie in some climatic or natural circumstances. At any rate, ecologists are concerned for the state of Primorye sea fauna because crabs are likely to modify it.