Flowers

High-rise Marsh Hidden in the Sea Fog
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The Yururi Island is impressive with its flat and long shadows, like a thin disk on the sea surface. The light emitted by the “Yururi Island Lighthouse,” which is built on a plateau, can reach all the surrounding areas because there are no undulations to obstruct it, making it a valuable guide for ships traveling offshore. At dusk and dawn, the faint light of this uninhabited lighthouse brings a poetic beauty to the eyes of those watching from the opposite peninsula. From near the foot of the lighthouse to the center of the island, there is a gently sloping high-rise marsh that defines the island’s vegetation, topography, and geology.

A high-rise marsh is where plant remains have piled up as peat until it rises above the surrounding area. High-rise marshes are formed in cold regions, highlands, or overly humid areas where microorganisms that decompose dead plants and fallen leaves cannot survive. Because they are higher than the surrounding area, there is no water flowing into the marsh. Therefore, high-rise marshes are usually maintained only by rainwater or snowmelt. The high-rise marsh on Yururi Island is also spread out on flat, undulating land. There is no river flowing into the marsh. However, in addition to rain and snow, the water in this marsh is also brought in by a different phenomenon than in other high-rise marshes.

That is sea fog. In the Nemuro peninsula area, especially from spring to the end of summer, we can see fog almost every day. This is caused by the warm air over the Pacific Ocean coming into contact with the cold sea surface off Nemuro, where the cold current passes through. According to some old data, 849 fog occurrences were reported in Nemuro in the five years from 1947 to 1951. If the probability of fog occurrence throughout the year is as high as 45%, it is not an exaggeration to say that in the summer, when the conditions are suitable for the fog to be generated, fog occurs every day. This sea fog that envelops Yururi Island has made the marshland grow. The reason why high-rise marsh, which is commonly found at high elevations, can be found on Yururi Island, which is only 30 to 40 meters above sea level, is because of the water carried by the sea fog.

This Nemuro’s unique sea fog also has a significant impact on the vegetation of the Nemuro Peninsula. For example, some “relics” can be seen in the marshes scattered around the Nemuro Peninsula. During the Ice Age, these plants were widely distributed but were left behind in the high mountains as the climate warmed. In Nemuro, these plants are still found in the lowlands. Sakaitsutsuji, which flowers at Cape Ochiishi on the opposite shore of Yururi Island, is a typical example. As such, the ecosystem of the Nemuro Peninsula is unique and precious. Of course, this is also true for Yururi Island. The high-rise marsh of Yururi Island, nurtured by the sea fog, could be called a treasury of such precious plants. Historically, there have been very few visitors to Yururi Island. So, it became the home to most of the typical northern plants. There are more than 300 species. Many of the wildflowers on Yururi Island are included in the Red List of the Ministry of the Environment, such as Bog orchid (EN), Vaccinium microcarpum (VU), Scirpus hudsonianus, and Pogonia (NT). In a sense, Yururi Island is a rare natural botanical garden where precious plants of Eastern Hokkaido are gathered in one place.

The clear water in the high-rise marsh of Yururi Island benefits more than just the plants. The water gathered here eventually flows out of the marsh and forms a series of streams flowing quietly down a very slight slope to the sea. The horses of Yururi drink water from these streams to keep them alive. The water of the high-rise marsh is the water of life for the horses living in an isolated world. The miraculous delicate balance created by the sea fog is the foundation of Yururi Island and the creatures on it. This is why Yururi Island had to be located off the Nemuro coast. Their lives are in the natural cycle of life existing only in this place.

Today, the island is still hazy behind the sea fog. It is truly a lost island. In the midst of the illusion, the flowers of the highland bloom, and the horses sleep secretly.