Lake Hinuma shore and Minami Oarai area

Lake Hinuma shore and Minami Oarai area

Lake Hinuma used to be a vast lagoon called "Atakana no Minato" in the Hitachinokuni Fudoki written in the Nara period. Now that the sea level has dropped and reclamation has taken place, the lagoon is divided into two separate parts, Lake Hinuma and Hinuma River. However, at high tide, you can see the sea water running up from the mouth of the Naka River to Lake Hinuma through the Hinuma River. It is also the only brackish lake in the Kanto region.

Lake Hinuma, is a brackish lake famous for shijimi clam fishing, which is done in the shallow areas of the Hinuma River and the east side of Lake Hinuma. The fisheries cooperative set a limit on fishing hour for four hours on weekdays from early morning to mid-morning throughout the year. Fishermen ride in small boats and use long poles with metal cages to rake shijimi clams of a certain size out of the sandy mud at the bottom of the swamp. The morning shijimi clam fishing offers an idyllic scene unique to Oarai visible from Onuki Bridge and Hinuma Bridge over the Hinuma River, where brackish water creates a village setting.

Lake Hinuma was registered under the Ramsar Convention in 2015 and is now an internationally important wetland preserved as a habitat for waterfowl. It is a wintering place for the endangered Steller's sea eagle and about 5,000 scaup ducks. The lake has a diverse ecosystem that is unique to brackish waters with shijimi clams, endangered Japanese eels, gobies, Japanese seabass, mullets, whitebait, and carp.

The lagoon around the Hinuma River was once Atakana no Minato, and is now a vast flat area of rice paddies that looks like a sea. You will cross vast rice paddy landscapes when you travel from Mito to Oarai by train or car. The paddy fields are filled with water from Golden Week holidays to early summer. The beauty of the clear paddy fields is viewed by students who commute from Oarai to Mito.