Coastal Area 12103 Adjacent waters of Isumi River mouth

Basic Information References

Reason(s) for selection Criteria

Characteristics References

These are the waters in the vicinity of the Isumi River's mouth. Like the Ichinomiya River's river-mouth tidal mud flats, the area around the mouth of the Isumi River is home to some of the few tidal mud flats including salt-water marshlands between Kujukuri Beach and Sotobo and serves as an important settlement ground on the Pacific coast of the Kanto Region for creatures that live in tidal mud flats. Species that have been confirmed here include Clithon retropictus, Assiminia japonica, Nuttallia olivacea, Sesarmops intermedium, Cerithidea rhizophorarum, Helicana japonica, Clithon retropictus, Angustassiminea castanea, Assiminea parasitologica, Assiminea hiradoensis, Asian clam, Arthritica reikoae, Tylorrhynchus heterochaetus, Laonome albicingillum, red claws crab, Helice tridens, Acmaeopleura toriumii, Macrophthalmus japonicus, Ilyoplax pusilla, and Masago goby (Ministry of the Environment Biodiversity Center, 2013b), and the Sotobo area retains highly unique and diverse tidal mud flats (Yuzuhara, Taru, personal communication).