The other way round: Ota Central Wholesale Market and Tokyo Port Wild Bird Park, I 東京港野鳥公園

 

This week, I divert a bit from Kanagawa to tell you my adventure in Tokyo. As long as I know, Kanagawa does not have such forest. I think not many forests with similar stories exist in Japan. Why is this place so unique? It’s because the forest is completely man-made, including its ground. Or, I should say at least the beginning of the place was artificial some 60 years ago. The climate of Tokyo gave ecological succession, which has given the biota there a “natural” forest. Don’t you think it’s interesting? It’s an ultimate “Nature Positive” place where a collaboration of nature and humans is still on-going. The name of the place is Tokyo Port Wild Bird Park 東京港野鳥公園.

First, the location. Tokyo Port Wild Bird Park is in Ota Ward of Tokyo, embracing Ota Central Wholesale Market which is more or less next to the Haneda International Airport. Toyosu Market is world-famous with lots of touristic attractions, but for ordinary Japanese living in coastal area of Tokyo, Kawasaki, and Yokohama, Ota Market is the place where vegetables, et al come from. As such Ota Market is BIG. The Park is encircling this huge wholesale market. The geographical feature is exactly due to the origin of the place. More to it later. To go there, please take a commuter bus from Shinagawa or Omori Station. From Shinagawa Station, take Metropolitan Bus Shina-98 品-98 and get off at Daitō-Ōi-Butsuryū Center (Mon-Sat) or Ota Market North (holidays) and walk 5-15 minutes. There are more services from Omori Station by Keikyu Bus, Mori 森 -24, 32, 36, 41, 43, 45, 47. Please get off at Wild Bird Park Stop or Tokyo Port Wild Bird Park Stop both of which stand 5 minutes’ walk distance from the Park Entrance. During your bus ride, you may feel uneasiness if this is the right way to visit a forest. Many passengers are working in Tokyo’s logistics center. The scenery from the bus window becomes more and more industrial. Never mind. Just get off the destination stop. Ota Market North, Wild Bird Park, and Tokyo Port Wild Bird Stops are facing the Park itself which suddenly appears as a mass of greenery within rows of warehouses. The journey may give you a very “Tokyo” experience.

One weekend winter morning,
I took a bus to the Park from
commuter bus gate 5 of Omori Station.
This Keikyu Bus route employs fuel cell cars.

Near the park, there is a huge warehouse of JR East.

Tokyo Port Wild Bird Park Stop.
The greenery on our right is the Park area.
The Park is circled by 8-lane industrial roads.

The notice board near the above stop says
“Park Entrance this way, 300m ahead.”
Just follow it.

We’ll find the gate.

The Wild Bird Park is now owned and operated by Tokyo Port Terminal Corporation. The entity’s origin was a public corporation for the development and management of Port of Tokyo. After several organizational transformations, in 2007 it became company limited. With this background, the entrance fee to the Park is free for kids in elementary school or younger. If a 7-9th grader studies in Tokyo, s/he can use the facility free of charge. Adults pay 300 yen at the ticket booth, but on every October 1 entrance is free for all as this is the day for Citizens of Tokyo. The management of the Park is done by Terminal Corporation, but the operation of Nature Centre in the Park is by Japan Wild Bird Society. So, the facilities here for bird watching is, I would say, excellent. The data gathered and published from Wild Bird Park is also very interesting. If you’re a birdwatcher and in Tokyo with some reason, this is the place you can come at least once. It is closed every Monday and New Year holidays. Otherwise, the place opens 9:00-17:00 (February - October) or 9:00-16:30 (November – January).

From the gate, walk up this slope,
which is, by the way,
a completely artificial geographical feature.

At the end of the entrance
there is an admin office with ticket booths.

The panel explaining how to for the usage of the park,
 with English translation.
The place has parking spaces.

Tickets are sold by vending machines.

Entering the Park.
Before going through the gate,
Park volunteers check your ticket.

The Park is “divided” by a wide industrial road coming in Ota Market from the north. Hmmm, I think this expression may give you an impression the human activity destroyed the original wild forest for economic activity … actually the story is completely the other way around. I tell you about it next week. Well, so, the Park has two sections: West and East. West Park is smaller and contains rice paddies and veggie patches where volunteers engage in organic farming. This section also allows kids to catch and release insects with nets lent by the management office at the entrance. i.e. West Park has more facilities for human activity, and, I would say, is “garden-like.” East Park has Nature Center where rangers of the Wild Bird Society are resident. East Park directly faces Tokyo Bay and has tidal flat. I had an impression the area is more “forest-like.”. Let me continue the next week why the East and West are like that. Please stay tuned!

Ota Market, a Sunday morning

West and East Parks are connected by
 a long bridge that goes over the Market.

Tokyo Port Wild Bird Park 東京港野鳥公園管理事務所

3-1 Tokai, Ota Ward, Tokyo, 143-0001
〒143-0001　東京都大田区東海3-1

Phone: 03-3799-5031
FAX: 03-3799-5032

You can send an enquiry to them by clicking the bottom line of their homepage at
https://www.tptc.co.jp/support/contact/park/yatyo

Cherry Blossoms along the Shore: drought in Kanagawa Prefecture, spring 2026

 

Cherry blossoms! On April 1, Yokohama Local Meteorological Observatory announced its indicator cherry tree reached full blossom. Since then, we have a couple of days for spring storm, but at least around my neighborhood they keep their best. Hurrah! They will be so beautiful even when they are scattering. I hope a couple of more days left for us to steep in their ephemeral splendor … That’s said, something strange is happening. For one thing, the Meteorological Agency announced their weather forecast for this week: it’ll be warm days including several “hot days” with the temperature at the level of June. Their next 3 months’ forecast also says “The average temperature in Kanto Region will be high, and rainy monsoon season could start earlier than usual.” Well, do you remember my “prediction?” Soon after cherry blossoms, summer will come.

The early coming of monsoon season should be welcome. Actually, this winter was so dry in the megalopolis Tokyo area. Kanagawa Prefecture was not an exception, nor Yokohama. Our reservoir lakes for water supply remain in critical condition. As of April 4th, the entire water storage rate for Kanagawa’s main water system, i.e. Sagami and Sakawa River Systems, is 39%. It’s after more than 2 weeks of on-and-off rainy days. The worst is Tsukui Lake with Shiroyama Dam (; my post on Oct 20, 2017). The lakeside Prefectural Park, Tsukui Shiroyama Park, is famous for its cherry blossoms. But … look.

When a reservoir is like this, so is upstream area. This is the recent Yadoriki Stream. The comparison tells obvious: water level is low.

At the end of March 2026.
Right bank is dry enough to become grassland.

Yadoriki Stream in standard March

Yadoriki Water Source Forest is for Sakawa River system whose reservoir lake, Lake Tanzawa, shows 46% of water storage rate, or 51% of average year on April 4th. Tsukui Lake, a reservoir lake for Sagami River, shows 16% of storage rate or 21% of average year. i.e. Yadoriki Stream has more water than the other water source forests in Kanagawa. It’s scary. Kanagawa Prefecture and Tokyo Metropolitan Government have a water sharing agreement, and in normal times the Prefecture diversifies 220 million m3 water per day to Tokyo from Sagami River. Since last month, Sagami River could not continue this, and the supply to Tokyo was reduced to 110 million, i.e. halved, per day. The rainfall from mid-March has not yet let reservoirs recuperate from the drought.

The water level immediately after
the water gate of Shiroyama Dam.
Could you see the water level is so low?

Water source area is like this, and so is the downstream, i.e. Yokohama. We Niiharu Lovers worry if this spring frogs have enough water for their eggs. Next to Yatoda rice paddies in Asahi-Yato of Niiharu, there are two small ponds. They normally hold water for gelatinous frog eggs. If it’s tube-like, they are eggs for toads. If they are foamier, they are for Japanese brown frogs. This year, none. Reason? Both of these bonds are dried up. Frogs need water from February to March for their tadpoles. If there is no water, they do not lay eggs to begin with. “It’s sad.” “Yes. Oh, I’ve found some eggs in ponds next to Ikebuchi Open Space.” “Me too! They are brown frogs, aren’t they.” “But you see? The other day, I’ve been there in dusk and heard an owl hooted in a tree over the pond.” “What!? They are eating eggs and tadpoles.” “Oh yes.” Survival of the fittest. This is a harsh year for frogs in Yokohama.

Dried up

From rice paddies another stream goes to
the (artificial) pond next to Niiharu Community Centre
 in Satoyama Park.
It also has poor level of water.
As the pond in the park is man-made,
it keeps water somehow. But …

Tadpoles in Ikebuchi pond.

If monsoon comes earlier than usual with enough rain, it could give some respite for our water system. Yet, volunteers who nurture Yatoda rice paddies in Niiharu are seriously worrying the prospect of this year’s rice harvest. I guess it’s not a problem only for amateur farmers in our community. With soring energy cost (i.e. it’s more costly pumping from agricultural waterway), low or none water level is worse for agricultural production by pros. Last year’s harsh summer yielded poor crop of potato and onions in Hokkaido, and the cost of these is shooting up now in supermarkets in Yokohama. Let us keep crossing our fingers as the situation improves and we have sufficient water supply this summer. God willing …

Small flow for
Asahi-yato rice paddies this March.
Correction: No flow.

The flows from Niiharu Forest gathers in Umeda River,
then to Tsurumi River.
Inevitably, the water level for Umeda River is low now.
 It would be good news for Egretta garzetta
to procure meals in Umeda River. But …

If you find environmental issues in Kanagawa Prefecture, please make contact with

Kanagawa Natural Environment Conservation Center 神奈川県自然環境保全センター
657 Nanasawa, Atsugi City, 243-0121
〒243－0121　厚木市七沢657
Phone: 046-248-0323

You can send an enquiry to them by clicking the bottom line of their homepage at http://www.pref.kanagawa.jp/div/1644/

For the 21st Century Japanese Nature Positive: Meiji University Kurokawa Farm

 

Kurokawa in Aso Ward of Kawasaki is an old community. It was a typical Satoyama village where farmers cultivated rice and veggies. They tended their hills with deciduous broad leaved trees for procuring logs as fuel and fallen leaves as mulches for their farms. They hand-crafted bamboo baskets made of many kinds of bamboos taken from their land and sold it as “Made-in-Kurokawa” brand in the old market of Hachioji where many people gathered for trade in hilly part of Kanto region (; my posts for December 8 and 15, 2024). The place still preserves the atmosphere of such idyllic life of yesteryears. Yet, we encounter the big road when we enter Kurokawa Forest from Haruhino Station side and go north. It is Tokyo Metropolitan Road 158 administered by Tokyo, not Kanagawa. Kurokawa Forest is on the border between Tokyo and Kanagawa. The mass of condos beyond Route 158 is the show of the biggest housing project in Japan, Tama New Town.

The crossing which demarcate
the old Kurokawa community
and suburban housing area.

As this location tells, Kurokawa experienced many transformations from the days of Kurokawa-brand bamboo basket. After 1945, the end of WWII, a part of Kurokawa became a ground for the US troops for their mission, perhaps of security something. When the mass development of Tama New Town went on in the 1960s, American part of the forest was a property of Mitsubishi Heavy Industries, not farmers, which bought the land and used it for testing their gears in their product development. By the 1990s, the company concluded using the land for such purposes in the middle of housing development of Tokyo was the unnecessary burden of property tax. They decided to sell it to somebody. That somebody turned out to be Meiji University. The university has the campus for the Faculty of Agriculture in Ikuta, Kawasaki, and looked around nearby larger land for their experimental farm. In 2012, the former ground for mechanical heavy equipment was reopened as an educational space for young people who plan to be a part of food industry in near future. The entire area of Meiji University Kurokawa Farm is currently off limit for public. There is a gate at its entrance where the security people check a proper ID. This winter, I happened to have a chance to attend a course there for Satoyama management by Prof. Noboru Kuramoto. This week, I tell you my impressions from the experimental farm.

Lecture building for Kurokawa Farm

The location of the campus is really at the end of Kawasaki City. We get off the Odakyu Tama Line at Kurokawa Station and walk to the Ceresamos Kawasaki farmers’ market. Walk around the Ceresamos ground and we find a road on our right which is an exit route when we visited art show in Kurokawa Forest (; my post for December 2, 2022). This time, we ignore the direction of art-show and proceed simply straight in rice paddies. Eventually, we meet a crossing of community roads. Take the left route which soon (10m or so ahead) returns straight road with a row of greenhouses on our right and bamboo forest on our left. The road curves gently to the right. We find white buildings over there beyond the hill which is Martial Arts Hall for Tama Campus of Kokushikan University where many athletes reside. And the gate for Kurokawa Farm is in front of us.

Ceresamos

Turning the corner of Ceresamos, please go straight.

In autumn,
the harvested rice was dried in a traditional way
in Kurokawa.

The crossing. Please take directions for green houses.

The road gently curves to the right.

The buildings for Martial Arts

The security gate for the farm.

From the gate, one paved road goes up a hill. When the university redeveloped the former testing ground of heavy industry, young Prof. Kuramoto was a person who was in charge of project management. At the beginning, he wished the slope would eventually invite fireflies dancing in June from a stream running on another side of the hill. According to him, such thing has not happened so far, as the stream on the other side was experienced the public works for flood control with U-shaped ditch, i.e. concreted. Anyway, the name of the slope is Firefly Slope. At the end of the slope are campus buildings such as Lecture Building, labs, and special warehouses for organic farming. These buildings are surrounded by experimental farming fields. Prof. Kuramoto said before these fields were mechanical testing ground for Mitsubishi enclosed by small hills with ups and downs. To teach students the recent mechanization in agriculture, such ups and downs were not desirable. So, the design of the place ordered the hills to be flattened. The excavated soil, by-product of civil engineering, was piled up as a new hill next to the security check point.

Firefly slope

Glass houses for experiments

Lecture rooms and labs

The experimental field after the excavation is surrounded by ridges of small hills that maintain old trees of Satoyama Kurokawa. They are mainly Quercus acutissima and Quercus serrata which before were nurtured for logs, charcoal baking, and fallen leaves for mulches. They are now very large trees as such utilization of them have stopped about 80 years ago when Americans came Kurokawa. A part of such old forest is utilized to search for the 21st century way of maintaining Satoyama forest. The constraint these days for such effort is labor shortage and proper utilization of knowledge for Satoyama ecosystems. In Satoyama restoration area of the university campus staff starting from professors to engineers in charge of the space experiment new gadgets (“mowing machine for USD 7000 a pop, anyone?”) and practical methods of restoration Satoyama forest that is tailor-made for Kurokawa’s climate.

Experimental cabbage patches, organic, of course.

The farmland is surrounded by old forests.

A mowing machine at the price of entry level of Porche.

A demonstration for moving heavy logs by mechanization

Having said that, Prof. Kuramoto and his team are facing budget constraints of the university. The administration requires long-term stability of the farm’s management. It means the faculty has to choose sooner or later to keep the forest of deciduous trees with frequent mowing, thinning, etc., OR to let evergreen Quercus myrsinifolia dominate the farm. Climax forest for the climate of Tama Hills is of Quercus myrsinifolia. As it is evergreen broadleaved tree, the forest of them is dark. Its forest floor starves for sunshine and ground vegetation has hard time to thrive. Money wise, the maintenance of such climax forest is economical due to its relatively poor ecology. Moreover, before humans started to manage the forest probably thousands of years ago, the forest of Kurokawa area must have been dark forest of Quercus myrsinifolia. The choice the faculty faces is an ultimate kind searching for the meaning of “Nature Positive.” The life cycle of a forest is far longer than for humans. This choice is difficult …

The current forest for Satoyama experiment.
With deciduous trees,
during fall and winter lots of sunshine come to the ground.

The newly created hill by the excavated soil next to the security check point encloses a small semi-dried valley. Its old water source is to the west somewhere on the hill surrounding the university farm. The valley is now sandwiched between the artificial mound to its north shore and the original hill of Satoyama time for the south bank. The university is hoping to make this part of their land public “park” where local people can come and enjoy strolling. At the moment, the plan is yet at a “hoping” stage. The end of the valley is a holding basin gathering water of the valley (a bit) and of the experimental field upstairs (the majority of the water). There is a discussion among faculty members how to proceed for the “park.” Prof. Kuramoto is an expert for Satoyama ecosystem. University also has professors for civil engineering and hydrology. As this is the matter of academia, the discussion keeps on going …

The entrance for the would-be park.
The depression on the left of the photo is a holding basin.

The inside of the “park” site has
lots of such trees with divided trunks.
It is evidence this place was once
a ground of procuring logs for fuel.
Normally, people regularly cut trees of
about 20 years old with 20cm or so diameter.
It was a nice size
to make logs and bake charcoals.
Such tradition was stopped
some 80 years ago in Kurokawa.
 Trees were left on their own devices
and have become tall trees like this now.

The forest floor of the planned “park.”
When the place was working Satoyama,
the floor was swept completely by
gathering leaves and twigs by farmers.
They used them for mulches over their farm land
 and for starters of their hearth fire.
 It made the Satoyama forest floor
 relatively nutrition-poor,
and hence with high biodiversity by lots of sunshine
 directly on the soil.

In addition to such technical discussions for Satoyama restoration, the university also thinks how to establish a solid connection with the traditional Kurokawa community. The community itself undergoes generational change now with the transfer of ownership from the landlords of 2012 to their descendants. As Kurokawa is designated as an Urbanization Control Area, and there is happening a renaissance for urban farming in suburbs of Tokyo, new and young landlords are constructive for managing Kurokawa area for the 21st century agriculture. But it is a different matter if they regard the closed area of academia is a part of their community ... Maybe, the forest of Kurokawa Farm stands at a unique position as a 21st century Satoyama Forest. Satoyama is Japanese way of achieving Nature Positive = cooperations of human life and Mother nature. Let us wait for the conclusion the academia of Meiji University will reach.

Could you figure out
a trace of some “campfire” on the ground?
It is at the end of January
on a rice field near the Kurokawa Farm.
This is a sort of “sacred” place
where the Kurokawa community holds a ritual
 called Sagicho 左義長 for the end of New Year’s festival
 for many many years as long as they remember.
 The tradition is living in Kurokawa community.

Kurokawa Farm of Meiji University 明治大学黒川農場
2060-1 Kurokawa, Aso-ku, Kawasaki, 215-0035
〒215-0035 神奈川県川崎市麻生区黒川2060-1
TEL ： 044-980-5300 

E-mail : noujou@meiji.ac.jp

Why are you here? Strange DNA finding for 2025 Yadoriki Stream

 

The eDNA study for Yadoriki Stream 寄沢 completed the 4th year in 2025. The species found in the specimen indicated nice environment for the source of Kanagawa’s tap of water. The aquatic creatures which left their DNA in the stream were the ones that could live mainly in unpolluted water. It’s good news. Several interesting things came up. Mr. Hasebe for Kanagawa Environmental Research Center, who analyzed the specimen, found the amount of nucleobase was larger from the water collected in April, compared with that for November. Though humans love to dive in fresh water in mid-summer, the amount of nitrogenous base during summer is smaller than for April and November.

Yadoriki Stream in autumn

When we remember the life cycle of water insects, it would be a predictable conclusion. Many of them, including EPTs (Ephemeroptera, Plecoptera, Plecoptera; their existence can suggest the level of water quality), leave water by the end of spring as adult mayfly, stonefly, caddisfly, dragonfly, … They spend hot summer on land to find partners, to mate and to lay eggs in water for the next generations. When humans enjoy specimen “hunting” in summer, many waterborne bugs have already left their cradle water.

Yadoriki Stream in mid-summer.
Surprising, it contains the smallest nucleobase.

In autumn, tiny nymphs come out of the eggs. As they move around in water, they will leave tiny bits of their DNA in the stream. Since the absolute number of such water bugs is larger during fall than for summer, we can catch their DNA bits more. But they are still babies if not remaining in eggs. In April, many of them are now bigger final-instar larva ready for the launch pad to leave water as adults. The amount of DNA they shed in water would be bigger than for fall or summer. Mr. Hasebe said the next research agenda would be to verify these hypotheses and to think about the meaning of it for the evolving ecosystem under climate change. We citizens keep on draining water in regular way and send it to the lab. Easy. Let us see how it will turn out.

A larva of Nemoura is eating
a larva of Tipulidae.
And we made them fixed
in alcohol …

Having said that, there is a strange finding. This year, Yadoriki Stream contained DNA for Japanese crucian carp. It’s an endangered species, endemic to Japan, nay, to Lake Biwa 琵琶湖 and to Yodo River 淀川. These two large water systems in Kansai 関西 are, I would say, not mountain streams, but have relatively gentle flow. The carp should love such environment and must be perplexed by rapid current of Yadoriki. Why there? We naturally concluded somebody has introduced them from far Kansai Area. The carp is important ingredient for traditional meals in Kyoto 京都 and Osaka 大阪. People farm them for culinary reasons. Endangered ones are the fish in wild environments. Biologically speaking, wild and cultivated ones are the same species. It’s easy for somebody to bring it to mountainous Yadoriki beyond Hakone 箱根. Maybe that person expected fun to fish crucian carp in Yadoriki. (By the way, to fish in Yadoriki Stream, you need an official license. Otherwise, you’ll be defined as “thief” by the police.) Or, s/he may have nobler intention of “restoring the population of endangered species.” Er, well.

Fishing carp here? No way!

From the fish’s point of view they have moved in an environment VERY different from their ideal home. We can simply expect many will die out quickly before leaving the next generation. Let us pray for them … Or there might be stronger individuals that could survive quick water flow. The next question is, does Yadoriki Stream have sufficient ecosystem that could sustain voracious appetite of the carp? The fish can grow 30cm long within 3 years and reach 60cm or more at the adult stage. If they eat up all the algae and the other animal-based feed, what would happen to the local tiny creatures of Yadoriki stream, such as mayfly, et al? It may not happen, but we must be watchful in any case.

Eggs for montane brown frog
recently in Yadoriki Stream.
They would be gorgeous meal
for carnivorous larger animals, such as carps.

If the release turns out to be successful, it will contribute to saving endangered species in wild. But there is a high possibility in such a case the ecosystem of Yadoriki would be different from the place before the arrival of the carp. Is this a desirable outcome for environmental management in water sources? I simply wonder …

If you find environmental issues in Kanagawa Prefecture, please make contact with

Kanagawa Natural Environment Conservation Center

神奈川県自然環境保全センター
657 Nanasawa, Atsugi City, 243-0121
〒243－0121　厚木市七沢657
Phone: 046-248-0323

You can send an enquiry to them by clicking the bottom line of their homepage at http://www.pref.kanagawa.jp/div/1644/