Terushima Cormorant Habitat

A Bare Rock 250 Metres Offshore

Terushima Cormorant Habitat is the whole of a small island off Izumicho in Iwaki City, Fukushima Prefecture, designated a national Natural Monument on 22 February 1945. The island lies about 250 metres out from the shore and stands about 30 metres above the sea, a bare cliff of tuffaceous sandstone.

What is protected is the island as a habitat and wintering ground for Japanese cormorants. Iwaki City records that the birds arrive around October each year and winter until March. A Fukushima Prefecture Board of Education source puts the arrival in mid-November and the return north between mid-April and early May, so the dates vary between accounts. Terushima Cormorant Habitat protects neither a building nor a view but a landing place on a migration route.

Why It Was Designated

The criterion applied was distinctive animals or animal communities in their natural environment. The cormorant as a species is not what carries the designation; the island where the cormorants gather is.

Two species come here, the Japanese cormorant and the pelagic cormorant, and Iwaki City records that they divided the rock between them, the Japanese cormorant on the upper part and the pelagic cormorant below. The city gives two reasons why the birds choose this place: the fish and shellfish they feed on are plentiful in the surrounding waters, and an isolated rock is hard for predators to reach. The prefectural source adds that the island is close to the southernmost point on the Pacific coast where Japanese cormorants can breed.

Appointing a custodian took an unusual turn. When the authorities moved to name one, Terushima proved to be state land that had never been entered in the national land register. It was registered in December 1959, and in March 1960 the city of Iwaki, then Iwaki's predecessor municipality, was appointed custodian. A municipal merger in 1966 passed the role to the present Iwaki City.

An Island Getting Smaller

This Natural Monument is shrinking. Tuff crumbles easily, waves and weather wear the rock down year by year, and Iwaki City states that the island now looks less than half the size it was when it was designated. Trees once covered the summit; hardly any remain.

Two collapses are on record. In June 2009 a storm surge brought down the western part of the island from a height of about 25 metres. In March 2011 the Tohoku earthquake, followed a month later by a shallow induced quake, broke off the island's tip.

A smaller island means fewer places for a cormorant to perch, and Iwaki City reports that the birds have been declining year by year as the rock shrinks. At Terushima Cormorant Habitat the thing being protected is visibly disappearing.

Visiting

Terushima Cormorant Habitat is an island offshore and is not somewhere to land. There are no opening hours and no admission fee.

The facing headland, once open for watching the birds from its tip, now lies within the grounds of the Onahama Ocean Hotel and Golf Club. Iwaki City records that since 1992 the Iwaki branch of the Wild Bird Society of Japan has held annual observation meetings at a viewing point set up inside those grounds under an agreement with the club. Anyone calling in individually needs to speak to the club before entering.

The nearest station is Izumi on the JR Joban Line, about fifteen minutes away by car. Terushima also appears in the Eight Views of Onahama, composed in the Edo period, as the island of the evening glow.