Great Divide: Haruhino-Kurokawa Forest 1

 

This year, Japanese map app YAMAP has rolled out a new product showing basins of rivers, large AND small, in Japan. The accuracy of the info shown there sometimes needs more refinement. (Example: why has Takigo Stream for Yadoriki Water Source Forest been cut into 2 in the middle?) But the creator of the app, Mr. Yoshihiko Haruyama, said the project is in its infancy. They welcome suggestions and new ideas from users with their new service. I found the app is very interesting. It’s often the case forests in our area spread along ridgs of hills and mountains. This means sometimes a forest which is considered as one unit can be divided into one or several areas when its valleys supply rainwater to different rivers. Unexpected borderlines can be found in YAMAP Basin Map. That’s what I found in Haruhino-Kurokawa Forest はるひ野-黒川の森.

We’re going up to the ridge of Haruhino-Kurokawa Forest.

Last month, Haruhino-Kurokawa Forest in Kawasaki City held an autumnal art show, their 9th. My impression from the recent show was not much different from the murmur in my previous post (on December 2, 2022). I’ve been there during its opening days and met several artists who installed their work. In sum, many of them found the wide-open space they could use attractive, and decided participating the project. OK. That’s that. May I mention they might not have thought much about communication with the multilayered ecosystem of the forest? … The artists approach would be similar to the newcomers to Western Nakagawa of Kohoku New Town (; my post on November 24, 2024). That’s unfortunate. The forest clearly shows the existence of people who care about the forest itself and engage in the maintenance works, not-so-flashy-as-art, continuously. Great Divide between two kinds of people, maybe …

Having said that,
this installation by Toshiyuki Tanaka
tries to capture mutual communication with the forest:
 "TANAKA Toshiyuki, Eyes in the woods."

“ISHIZAKI Kouji, Hope”

“TAKEMOTO Suguya, Floating Object in the Valley.”
This installation would be
from the same idea of Tanaka’s installment above.
But I was horrified to see this plastic seats floating
above the abandoned rice paddy.
Reason? Please wait till my next week’s post.

“SATO Hideyuki, Dinosaur Egg.”
Ditto for this fiber-reinforced plastic.

“LYU Dian, Fountain.” Ditto for this.

“TACHIKAWA Mariko, Surrounded by Delicious Sunlight.”

“HARADA Riito, Convey my heart.” This I like.

“MURATA Yuta, Place of Soil.”
His continuous work from the previous show.
I’d like to see how he develops
his way of communicating with the land.

“MACHI Kiiko, No!”
She emphasized she was strongly against all the wars of the planet,
and said NO in a large voice …
but why in this forest, I wonder.

“TSUKASA Kana, Scene.”

“UTSUMI Hitoshi, Secret Base.”
This one is also I like.
He tries to have a fun with the forest as a kid.

“ABE Yasumichi, Loop.”
He’s not the only artist of this show
who presented a sculpture made of stone.
In a sense, it’s a traditional way of humans in the relationship with nature.
What does it mean, I wonder.
Is it the beginning of gigantic stone palace of Versailles
with completely geometrical garden?
I suspend my opinion about this …

I have not yet met people from groups who engage in regular maintenance work for the forest. But according to this page, the area has lively communities, some of which do forestry works for the Forest. Moreover, they’re proud of their dirt-work beyond the desk theory. I had a feeling they are clearly succeeding in it. When I’ve been there last month, it was still a bit early for trees shedding leaves. Yet, the general impression Haruhino-Kurokawa Forest showed was bright with rustling sounds of leaves. The paths inside were well maintained for strollers to enjoy. People are controlling the undergrowth of the forest nicely and treating the damage by oak tree wilt. That’s something. As long as I know, the tenure of the land for Haruhino-Kurokawa Forest is a mixture of governmental, private and corporate entities. The teamwork of volunteers from many corners of Kawasaki and some help from pros hired by the City has done a really good job. Their endeavor in the end created the wide space the artists installed their work. Moreover, the success of such handiworks was scientifically measured in terms of basins.

When we check Yamap Basin Map, the ridgeway of Haruniho-Kurokawa Forest is the watershed between Tama River and Tsurumi River. The streams go down the north slope to the direction to Haruhino Station provides water for Tama River. The water from the south slope including an experimental farm of Meiji University goes to Tsurumi River. From 2015 this water to southward was checked by the group of researchers from Tokyo University of Science. The result was amazing. I tell you this next week. Please stay tuned!

If you find environmental issues in Kanagawa Prefecture, please make a 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/

Good evening: birdwatching swallows in the mouth of Tama River II

 

This year, actually, city swallows chose a field of reeds near JR Kawasaki Station 川崎駅. Oh yes, that terminal station for industrial Kawasaki City 川崎市. The reeds are on Tokyo-side of the bank of Tama River, 多摩川 but watching birds from Tokyo side is blocked by the other vegetation like trees and plume grasses that love drier soil. Kawasaki-side is wide open and provides easier view for birdwatching in the reeds field spreading along the waterfront. That evening, we met at the north exit of Minatomachi Station 港町駅, the next stop from Kawasaki Station for Keikyu Daishi Line 京急大師線. The area was recently undergone a large “gentrification” development. Posh tower apartments are dominating the exit area of the station. Childcare facilities and indoor golf training gym are claiming their value with stylistic billboards. Very apt for city-slicker swallows waiting for an international flight, I thought.

Minatomachi Station

The tower apartments

Already in front of the station we could feel a wind of (relatively) cool evening air from Tama River and Tokyo Bay. We walk a couple of minutes along a boulevard between the modern skyscraper apartments, and the south bank of the River was just before us. Joggers and strollers enjoyed the evening after boiling heatwave of Tokyo. We took few steps up to the bank. The people of Wild Bird Society of Japan (WBSJ) are waiting for us with powerful monoculars focusing on the reed field on the Tokyo-side. At 18:15, the sun as not yet set, but the sky was definitely heading for night. The downstream of Tama River pours into the Bay at the right next to the Haneda Airport 羽田空港. It was busy evening and lots of airplanes coming and going over there. Huge bright lights of airplanes competing with the setting sun. The machine looked so near our position. I felt a wonder wild swallows make this scenery their home.

Boulevard. Could you see Tokyo-side over there?

People from WBSJ were waiting for us.

Lots of egrets were also there. This is Medium Egrets.

And airplanes.

We waited for several minutes. Somebody among us found tiny dots flying around above an apartment roof on Tokyo-side. “Swallows!” Murmur in a hashed voice spread among us. Just like us humans, evening swallows were heading home from their daily activities. The way they came home was also like us; individually. The birds were not a flock, but flied solo and looked like saying good evening as they encountered their neighbor in their bed town. In general, they flied around for a while before descending on the leaves to sleep. Many glided very near to the surface of the River where they could hunt bags for an evening meal. It’s like we dropping in supermarket for prep of evening meals. Several of them looked playing around with another swallows. Is it like enjoying happy hour in Izakaya?

Swallows made this area for their beds.

The first sighting was around here.
I couldn’t take a photo of them!

I thought I photographed the moment
a swallow flying over the water surface …

One by one they went “reed” home and made themselves comfortable to sleep. Some were staying “Tama River Izakaya” until the last (oh, yeah, literally) minutes before sunset. But in the end, they were in “bed” at the tip of reed leaves. It seemed to me they did not mind their neighbor swallow were there VERY near to their bed. … Like school dormitory, or, similar to us in apartment blocks with the neighbor’s door just next to us …?

In this photo, there are so many swallows.
Almost all the blackish dots at the end of reed are swallows ready to sleep.

At the sunset the event was over. WBSJ lent us very powerful binoculars to enjoy the birdwatching. They also explained us the lifecycle of swallows and shared their accumulated experience to watch swallows “Bedtime” event. They also gave us tips to take nice photos. I understood why this event was SO popular, with uber-competitive entries. Every year they start lottery entry for nation-wide events early July (; their HP is here). If you’re interested in nature watching, please try. It’s really worth experiencing it. Besides, having birdwatching on a cooler bank of Tama River after sweltering business day in Tokyo is really GOOD.

The binocular I borrowed.

People from WBSJ explains.

Wild Bird Society of Japan

https://www.wbsj.org/

Schooling days: birdwatching swallows before they leave Japan

 

Swallows are birds living near us. They build their nest under the eaves of our home, the walls under the roof, things like that. In late spring they come to Japan, decide where to raise their chix, mate, hatch the eggs, feed their kids, … then? If lucky, the chix should grow big enough to leave such a small estate of their nest (; my post on July 5, 2019). Come to think of it, we see their childcare days, but not afterward. What will they do? Returning straight to southern places, like Taiwan, ASEAN countries …? Can the teenager swallows take such a long-distance flight without learning how to feed themselves and gaining enough strength for a long haul? Unlikely. What then do they do before they leave Japan?

Busy holding eggs

According to the people for Wild Bird Society of Japan (WBSJ), swallows love to rear their chix in human settlement because of security reasons. Having their eggs near us could prevent onslaught by predators like snakes, mammals, etc., as we positively expel their approach. When the chix become big enough to leave their nest, young swallows fly around to learn feeding themselves first. Schooling days will last for about 3 to 4 months. When they think they have eaten sufficiently to maintain their stamina for returning to southern countries, they individually decide their departure. i.e. They do not build a flock like swans for migration. However, during their preparation days, they behave like a member of a group. Moreover, they do so only from dusk to dawn. They sleep in a particular place en masse. At sunrise and sunset, lots of lots of swallows congregate in a special place. In Japanese, such behavior is called “Bedtime for swallows つばめのねぐら入り.”

In any case, their tales are cute.

During the prep days for a long trip, swallows commute between such bedroom and their hunting sites daily. At dawn they leave home, hunt and eat during day time, then return to bed at dusk. Their bed is the top tips of reed leaves. The birds are so light that they can stabilize their body on such a delicate structure. Also, they do not use a pond with a handful of reeds. They sleep in a group to achieve a certain level of security by the power of numbers. So, they need a large field of reeds for Bedtime. i.e., If we plan birdwatching for Bedtime for swallows, we must go to a riverside with a sufficient colony of reeds.

It’s a scenery of Sagami River 相模川
where its downstream begins more or less.
Sure it has a bit of reeds on its bank,
but we don’t think it is “substantial.”
So do swallows. No hostels for them here.

WBSJ is yearly updating an introductory map for us to witness “Bedtime.” Some sites, like Watarase Yusuichi 渡良瀬遊水地 listed in the Ramsar list, the field of reed is large. For Watarase, they have 33 km2 of reeds and can accommodate constantly 30000-60000 swallows to sleep. Er, well, having said that, we do not have to plan a holiday travel for swallows, if we do not require the size of numbers for swallows. There are several spots in metropolitan Tokyo area where swallows sleep during summer. For example, Flood-ControlPark for Sakai River of Kanagawa Prefecture 神奈川県立境川遊水地公園 (; my post on January 28, 2022) has a size of field of reeds capable for being beds of 300-500 swallows. We can watch them come to sleep from late July to early August. A bit larger swallow hostel with good access (for humans) is near Haneda Airport. Yup. That International airport for Tokyo. It is in the estuary of Tama River 多摩川.

A beautiful sunset in Tama River, Tokyo

Every year, WBSJ holds a couple of “Bedtime” watching events near the airport. It’s a uber popular dusk and difficult to secure the seat, allocated through lottery. But, ta-da! This year, Naomi hit a Jack-pot, and had a chance to join the occasion! This week and the next, I tell you my adventure with swallows near Haneda, on the bank of Tama River. Due to hydrological reasons the fields of reeds normally appear on the Tokyo side of the bank, but it is easier observable from Kanagawa. So, in this adventure, I keep my foot in our home prefecture. 😉 The size of the field is definitely larger than that for Sakai River. The reeds along Tama River can host 3000-5000 swallows regularly. Oh, one caveat. Swallows and reeds do not stay in the same spot every year. People for WBSJ told us for 2024 they moved a bit upstream, away from Tokyo Bay. So, my report for this year may not exactly apply for the next year. Next week, I tell you where I’ve been. It was in 5 minutes’ walk from several stylish tower blocks. Lots of residents did their evening jog along the river. 😊

I think it’s a good place to sleep,
not only for swallows but also for humans.

Wild Bird Society of Japan

https://www.wbsj.org/

Survival Game: Lives and the Lingering Effects of Flood Threats from Rivers in Kanagawa Prefecture

Last fall, we live in Metropolitan Tokyo area were hit twice by Super Typhoons, Faxai and Hagibis. In Kanagawa Prefecture, several were killed by landslides and flood. Tama River, marking the border between Tokyo and Kanagawa, flooded to kill a person in Kawasaki. Very fortunately, though, the banks of large rivers flowing in Kanagawa Prefecture did not collapse. It kept the damage from the typhoons somehow lesser in our towns compared with the other places like in Chiba or Nagano. In any case, it was a terrible experience. (For the photos about the disaster by Hagibis in Kanagawa, you can find them here, the site by Kanagawa Shinbun Newspaper Co.) 

A scenery showing how close it was for Sakawa River.

One of my seniors of Kanagawa Forest Instructors lives in Hiratsuka City 平塚市 along Sagami River 相模川. The bank of the river has been for her relaxed strolling. Then on 12^th of October, the city issued an evacuation order to her neighborhood because of the torrential rain, and the warnings from 4 dams, Doshi Dam 道志ダム, Miyagase Dam 宮ケ瀬ダム, Sagami Dam 相模ダム, and Shiroyama Dam 城山ダム, for imminent release of water to Sagami River. “You see, our 50-inch TV was brand-new, and it was on the first floor. So my husband and I brought it first to the second floor. Then, my son came home. We all three frantically moved our furniture to the second floor. Gosh, how heavy our microwave was! Finally, only the refrige remained. We discussed if we can carry it to the second floor. It was impossible. We decided to let go the machine and the food if the flood comes …” Then, they got into the car with few items of their belongings and headed for the designated shelter that was a nearby elementary school. “We found the place was damned full. No room was left for our family. In any case, the school was also near the river so that we moved on to another school that was in higher elevation. It was full again. We drove around for some time to find a safer place, and ended up in a school not in a walking distance from our home, but on a hill safely away from the river.” Her family stayed in the gymnasium of that elementary for the night of October 12th. They were distributed 2 blankets per person to sleep on a hard wood floor. “You see? I don’t know why but I grabbed my yoga mat when we evacuated our home. It turned out to be a jackpot-move. At least I could lay on the floor more easily. It was hard to sleep at that night. Many kids started to cry, and lots of elderly people had hard time to get up to go to toilet …” Thank God. Sagami River held up even with the discharge from four dams.

A goal post for soccer turned into a jumble of scraps
 thanks to the inundation from Sagami River last fall.

One of my pals as Forest Instructor is an officer working for Kanagawa Water Supply Authority 神奈川県内広域水道企業団. They are in charge of Doshi Dam, Sagami Dam, Shiroyama Dam, Miho Dam and water intake weirs in Sagami and Sakai Rivers. On that night they were on an emergency night shift. “You see? We did not want to discharge water but the speed of rising water level was abnormal. In the end, the gate of Shiroyama Dam was opened 5 minutes before the final warning was issued by the Prefecture. It was a close call. Thank God, Sagami River did not overflow … That was a super night.” Well, even though, the water of rivers in Kanagawa, Sagami, Sakawa, Tsurumi, et al rose quite close to the limit. My instructor senior went to the river bank several days later. “You see? Only the top 10cm of tall reeds kept its green, and the rest was covered by mud. In addition, quite many of them were completely beaten down to the same direction. The power of flood water was horrible …”

Could you see in this photo at least
 the water reached to that level from Sagami River?

The phot was taken on the bank of Sagami River early January.
 The vegetation was recovering to green,
 but those flatten muddy reeds tell the power of water.

It could be indeed miraculous the only death by flood of rivers in Kanagawa Prefecture was on the border with Tokyo. I’ve heard several communities received substantial damage in their rice paddies and tangerine orchards in the west of the Prefecture. Water of the rivers kept muddy for more than a month after Hagibis. Humans are still struggling to recover from the weather incidents. Having said that, to some extent, it would be an evidence the Prefecture does well to control rivers in the territory. Yeah, on October 13^th, a Rugby World Cup match between Scotland and Japan was held in Nissan Stadium even though the flood basin of Tsurumi River inundated the sports park surrounding the Stadium. It was thanks to a very good civil engineering design for flood control. Still, the power of Tsurumi River from 12^th of October was shocking. It extirpated many forests that existed along the Tsurumi River before Hagibis.

Sakawa River in the middle of November 2019.
 The water was still raging.

This photo of Tsurumi River was taken last August
 before super typhoons came.

This is for the same place as above
 after the typhoons in November.
 Frankly, I was shocked.

Then, what happened for wildlife along the river? In January, the waters of rivers have finally returned non-muddy. But the effect is still lingering. I knew there was a large Japanese walnut tree on a bank of Tsurumi River that was a home for lots of pacific reef herons. Then, the flood uprooted the tree, and these days I cannot find black herons there … The birds have received the damage too. Still, the place near Sagami-Ozeki Weir 相模大堰 on Sagami River has welcomed many migratory water birds as usual this winter. In the area, we have found accumulation of poops by Japanese raccoon dog family, and feces of wild Japanese hare. A peregrine falcon perched high-up on the power transmission tower near railroad bridge for Odakyu Line. Aster kantoensis, which is an endangered species (CR+EN in Kanagawa) were survived … Whatever happens by super typhoons, they are resilient at least for now. Is there anything we can do to ride on this strange series of weather with them together in 2020?

102140: This is also the photo of last August
in the bank of Tsurumi River where
 pacific reef herons returned before sunset.

Immediately after the typhoons,
 the tree itself stood with herons.
 But could you figure out
 the back of their nest is in a mess with uprooted trees
 and garbage from the river?

The city cleared the space for further riparian maintenance.
 No tree in January 2020. No herons.
 But could you see a Eurasian coot in the middle?
 Life goes on after the storm …

Poops of Japanese raccoon dogs
 on the dusty bank of Sagmi River this month.

Humans are busy to restore the bank for Sagami River.

I was a sort of impressed with these
 as hare was so resilient to leave their dropping here
 on the riverbed after the flood.

Sagami-Ozeki Weir in early January 2020.
 It withstood with the flood water
 which left such muddy vegetation and sandbags around.

But goose came to the Weir as usual this winter.

A nice couple of Eurasian teal,
 regulars for winter at Sagami-Ozeki Weir.

Somewhere in this photo,
 there must be a peregrine falcon …

If you find environmental issues in Kanagawa Prefecture, please make a 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/