環境

Reports from our Seasonal newsletters

Special Edition on the Annual Report about the Foundation’s Projects

No. 124 “Viewing Mount Fuji from Tamakawara Bridge”

The Foundation Newsletter, Tamagawa (English Version)

Wildlife around the Tama River

■Viewing Mount Fuji from Tamakawara Bridge ■

Alighting at Yanokuchi Station on the Nambu Line, and turning left onto nearby Tsurukawa Kaido Street, I walked on to the Tamakawara Bridge over the Tama River. Halfway up the bridge I looked back, and my eyes were struck by the sight of Mount Fuji, with the pure-white snow adorning its peak that makes it truly worthy of the term “sacred mountain”.
Expecting to see the full view of the mountain, I crossed the bridge and continued to walk upstream alongside the river’s left bank. Then across the Tama River, I saw the majestic view of Mount Fuji rising high above the peaks of the surrounding Tanzawa Mountains. The view of the snowcapped summit of Mount Fuji is probably best in the morning on clear, sunny days from the end of October until the beginning of March.
On the opposite bank (the right bank), there is a long avenue of black locust trees (robinia pseudoacacia), which is known as Acacia Street. In May, the pretty white flowers bloom, with their sweet scent drifting all around.
Photo ＆ Text Hidehiko Endo

Opening Article
I Want to Meet Fish

Sakana-kun
Fish Life Co-ordinator
Visiting Associate Professor, Tokyo University of Marine Science and Technology
Ministry of the Environment “Life on the Earth” Supporters Club

Various issues relating to the environment are conveyed through the media, such as global warming and environmental pollution. I have been given opportunities by fishermen across the country to sail on their boats so that I can meet fish. Fishermen have told me that the types of fish caught and the seasons when they are caught are changing. Even fish that have never been previously seen are being caught. I have personally had many opportunities to see these changes as they happen. These kinds of phenomena make us think that they are due to the impact of environmental changes.

In some marine areas, the seabed is found to be quite dirty and there is an accumulation of sludge, which makes it look like a bottomless swamp. I occasionally participate in marine environmental activities. Each year, the Sea Beautification Society of Kanagawa Prefecture organizes seabed clean-ups around the ship Hikawa Maru in Yamashita Park, Yokohama. More than 100 people participate, along with divers, in this cleanup. A variety of garbage is picked up during this event. In Tokyo Bay, activities aimed at cultivating sea wrack and wakame seaweed are being carried out. Seaweed absorbs nutrients in seawater as it grows. The seaweed that has grown well is eaten and enjoyed by everyone.

There are known to be more than 4,000 species of fish in Japan. Many species of fish live in the sea, but there are also fish that travel between the sea and rivers, such as eels, salmon and sweetfish. Each fish has its own idiosyncrasies. Once, when I was on a television program, I was very surprised to see that shoals of Arabesque greenling engage in strange behavior that one sees only around Okushiri Island in Hokkaido; in order to eat plankton near the sea surface, the Arabesque greenling form a big underwater “greenling column.” A more familiar fish species, the flathead mullet has also a unique behavior. Usually fish are captured once they are caught in a net, but the flathead mullet is able to jump out and escape back into the sea. It is a mysterious fish that can make a narrow escape when in danger. When I was a small child, I was watching from a breakwater when I saw a flathead mullet jump, and I mistook it for a flying fish. There are fish that croak; Anemone fish and nibe croakers make a noise to intimidate predators or when engaging in courtship behavior. Fish such as the striped beak perch, the thread-sail filefish and the forktail bullhead, a variety of catfish, also make a noise. The saw-like dorsal fin of the little redfin velvetfish, which is just 5cm long, has a strong poison. There are many more fish with unique behaviors, such as fish that can change their color in an instant, to provide protective coloration, and fish that dive into the sand.

When I was a small child, I was brought up in Ayase, Kanagawa Prefecture, and I have few memories of the Tama River. The year before last, I participated in an event organized by a group involved in the conservation of the river basin area, which involved catching juvenile sweetfish in a fixed net, counting them, and then returning them to the river. When I was shown around the area from the upper reaches of the river to the source, I saw how the river was surrounded by the abundant verdant beauty of nature, and I was greatly moved by the fact that one would hardly think that this place was in the Tokyo metropolitan area. Near Ayase is the Sagami River. When I went there with my family to play when I was a child, I once fell in the water and was swept away. The river was fast-flowing and there was nothing I could do. I thought that that was it for me, but fortunately an angler fishing for sweetfish nearby kindly rescued me. In addition, my cousin and I were once swept away when we went fishing in a river at Shirahama in Chiba Prefecture, so I have had two scary experiences in rivers. Even now, I still remember my experiences of the terror of rivers, together with the memories of the beauty and fun of rivers.

With regard to fish, rather than desperately trying to study and remember what I have learned, I have greatly enjoyed reading illustrated books and have remembered information naturally. For example, when checking names, I have noticed that the Chinese emperor fish is called fuefukidai (whistle-blowing bream) in Japanese because it looks like it is blowing a whistle. Furthermore, when looking at these illustrated books, I get a strong feeling that I would like to meet those fish, and so I have been greatly moved when I have finally met the fish that I wanted to meet. When I was taking home a fish that I had caught in a river and I was thinking about how to look after it, I paid attention to ensuring that the tank where I was keeping it matched as closely as possible the environment where I caught it, recalling the scenery around the river, the current, depth and temperature of the water, whether the riverbed was sandy or muddy, and what waterweed was in the river.Among the pollution in the sea and rivers is a variety of things that people have thrown away and which are not broken down by nature, so they just drift in the water forever, or accumulate on riverbanks or in inlets. I have seen birds and fish eating or swallowing these by mistake, and fishhooks getting stuck in their bodies. I feel very sorry for them. At the Marine Science Museum of the Tokai University Social Education Center in Shimizu, Shizuoka Prefecture, as part of the lessons for elementary school pupils, classes are conducted to open up the stomach of a longnose lancetfish to see what comes out of it. Apparently, various things that have been thrown away emerge when it is opened up. You can imagine how polluted the sea must be. In addition to the visible pollution, there is invisible pollution, due to various things that have dissolved in the water. In previous decades, pollution-related diseases caused by wastewater from factories were a serious social problem, but now it is said that 60 ? 70% of the pollution in the sea and rivers is caused by domestic wastewater from ordinary homes. For example, if one dissolves one spoonful of soy sauce in water, it takes 600 liters of water to dilute the water sufficiently for fish to live in it. When I heard this, I was so surprised. This is the equivalent of three times the quantity of water held by the average bathtub. Soy sauce is irreplaceable in cooking. Soy sauce brewery makers also put a great deal of time and effort into its manufacture. So we must value every single drop of soy sauce! It is scary to think that soy sauce in as small an amount as a spoonful, or other contaminants in such small amounts, must be constantly discharged from households across Japan. I think that it is necessary for us to do our utmost to reduce waste and try hard to find other ways of using things such as soy sauce left over from eating sashimi, and eating things up rather than throwing them away in general.

Japan is blessed by a rich natural environment, with clean water and delicious food. I believe that it is important that we do not take them for granted, and that we are conscious of and grateful for them. We may not immediately know how to protect nature; we will not understand until we actually look at beautiful views of nature. I believe that the desire to take good care of the natural environment grows in one’s heart by playing energetically outdoors in rivers, in the sea, and in the fields, and coming into contact with animals, beginning when one is a small child.

An abundant fishing ground provides a diverse range of fish species, so diverse that we almost don’t need to go to far away oceans to fish, and such fishing grounds tend to be surrounded by a rich, verdant land. Mountains and rivers supply the nutrients of nature to the sea, like the blood flowing in the bodies of humans. The important thing is that they are linked. If we actually sail on boats and go to rivers or the sea, we gain a true sense of how they are all interlinked.

When I was a small child, the word “eco” was not as pervasive as it is today. Serious initiatives relating to the environment were not flourishing as they are today. Various events such as abnormal climatic conditions and natural disasters are happening in many parts of Japan and around the globe, and as we observe them, we have begun to seriously think that we must do something in earnest to tackle them. In our homes, conversations about reducing waste and separating the waste that is created, as well as striving to ensure that electrical items are switched off when not in use, which are carried out by every family member from children to adults, will further promote communication, nurturing the desire to take good care of nature. I think it is wonderful that such good practices will gradually spread throughout society.
Together with everyone else, I, Sakana-kun, will also continue to consider the environment, and to lead an eco-friendly lifestyle!
Thank you for your continuing cooperation.

Special Article

The River Culture Created by Local Citizens
An Introduction to Citizens’ Activities in the Yamoto River (Tsurumi River), Yokohama

Hiroshi Watari
Secretary-General, Aoba-ku River Enjoyment Society

Establishment of the Aoba-ku River Enjoyment Society
The Tsurumi River is a Class 1 river that runs for 42.5km from its source at Oyamada in Machida City to its mouth at Namamugi in Yokohama’s Tsurumi-ku. The basin adjoins the Tama River and the whole of the river basin is a densely-populated area, so it can be described as a typical urban river. In the northern part of Yokohama, it is called Yamoto River and is close to the hearts of local people. In 1988, there was a voluntary screening of the documentary Yanagawa Horiwari Monogatari (The Story of Yanagawa’s Canals) (1987, produced by Hayao Miyazaki, directed by Isao Takahata) in what was then the ward of Midori Ward. In 1989, desiring to turn the Yamoto River into a river signifying the hometown and to preserve a good natural environment, the members of the executive committee for the screening formed the Midori-ku River Enjoyment Society (following reorganization of the wards in 1994, the Aoba-ku (ward) was created and the name was changed to the Aoba-ku River Enjoyment Society).

Holding the Playing Around on Rafts on the Yamoto River Event
The majority of the members were housewives, many of whom based their activities on their strong interest in diet, the soap movement, acid rain, atmospheric pollution and garbage separation. Desiring to “stop being a threat to the environment and cherish our natural environment,” their activities began with the observation of the waterfowl and plants of the Yamoto River, the surface of which could not be seen due to high fences and thickets. Then, as they wondered increasingly whether it might not be possible to have fun on the river that they had enjoyed when they were children, this idea developed into “playing around on rafts.” The materials for the rafts were moso bamboo obtained nearby, and the members’ husbands were roped into making a trial raft. Members progressed through trial and error. As there were no water-related amenities then, members had difficulties lowering the raft down a concrete river wall and getting onto the surface of the river to check whether the raft floated. Finally in 1989, the members were able to hold the first “playing around on rafts” event beside the annex of the Aoba Ward Office, upstream from the Ichigao overpass on the Den-en-toshi Line. The following year, they asked the Kanagawa Prefectural Government to build a facility to provide easy access to he river, so the Yokohama Flood Control Office was kind enough to install water-related amenities that made it possible to get to the surface of the river. By the time of the seventh event, it became difficult to hold it under the sole auspices of the Aoba-ku River Enjoyment Society, so we invited various groups in the Tsurumi area to participate. The event then came to be run by an organizing committee and this year we held the 21st event. It has become firmly established as a summer feature of Yokohama’s Aoba Ward, and the children of the area enjoy the first days of the summer holiday on the surface of the Yamoto River.

Towards the Spread and Enhancement of the Group’s Activities
As members have participated in various workshops, the focus of their interest has spread to life, rivers and water, greenery, living creatures, environmental education and clean-up activities. While conducting regular activities in the form of the restoration work of natural vegetation in flood channels, and surveys of the living organisms and water quality in springs and the Tsurumi River, the group has also engaged in a wide range of activities such as support for learning at nearby elementary and junior high schools and walking trips around the river basin.
What we must not forget is the existence of the organizations that support our activities, including the Keihin River Office of the Ministry of Land, Infrastructure, Transport and Tourism, the Kanagawa Prefecture Yokohama Flood Control Office, the Tsurumi River Watershed Council and the non-profit organization Tsurumi River Basin Networking (commonly known as Npo TR Net; Chief Representative: Professor Yuji Kishi, Keio University). TR Net, above all, provided tremendous support, from the provision of new knowledge to cooperation in our activities. The Tsurumi River Watershed Master Plan, which was signed by local governments within the Tsurumi River basin, including the governments of the Tokyo Metropolis, Kanagawa Prefecture, Yokohama City, Kawasaki City, Machida City and Inagi City, is a key pillar supporting our activities.
The average age of our members is increasing, but we will continue to emphasize the importance of continuing to diligently undertake even small activities, based on the approach of “welcome those who arrive, do not pursue those who go”, which is a way of supporting the citizens’ culture of Tsurumi River without getting carried away.

Full Text

Download PDF　(Japanese Only)