Vampires Strike Back! … not yet Halloween

 

Finally, it seems to me, fall has begun honestly for Kanagawa Prefecture. It’s about time. Although flower cycles are still in confusion (that’s for next week), all creatures including humans are feeling respite from LONG, HARSH, BOILING summer. Yeah. It’s a good thing. Autumn. We should be fair for all living things around us enjoying easier weather. Yet … the same condition also gives OK for vampire leeches in Tanzawa to be active.

Somewhere here, vampires are waiting …

In Yadoriki Water Source Forest, especially after showers, the blood suckers are eager to paste on the skins of mammals and amphibians. We simply walk around the strolling courses off the paved path, and they appear here and there, trying to reach our bare skin for blood. Poor creatures. They must have been starved during the days of baking sunshine + occasional downpouring of summer 2024. I guess those which poke out from the crannies of trekking roads are survivors. They endured strong sunlight, laying down under the pebbles for 3 or so months. They escaped landslides when torrential rains attacked the water source forest and washed over the topsoil. Vampire leeches. Tough guys. Still, I think they are smaller than in the previous years.

An apparent scenery of landslide in Tanzawa

I would say such foggy trekking road is so beautiful.
But … be ware of vampires.

If during summer they had sufficient nutrients = blood, they should be 3+cm long in October. This year, nope. They are skinny. They are more or less 1cm long. They move almost frantically on our trekking shoes for finding skins, even when we drenched our gear with DEET or some leech repellent. In encounter with tiny blood suckers trying to reach my skin for blood, I unusually felt sympathy for them. Oh, so, you must be very hungry, aren’t you? Haven’t you noticed your entire body is absorbing strong venom, called DEET, which would be lethal for you? Are you OK? What a Faustian question …

Japanese skimmia are having lots of fruits
these days in Yadoriki Water Source Forest.
Caution:
the plant is poisonous from the root to the tip of head.
Their ripening red fruits are attractive
but lethal for kids when they eat them.

I haven’t heard any news reporting annihilation of vampire leeches due to climate change. Rather, they say their habitat range is expanding. Previously snow-covered mountains during winter are now snow-less or ice-less, which is easy for leeches to ride over the cold days. Then, there is a nation-wide exploding population of deer. They can move around in mountains carrying leeches between the nails. Now, leech problem is in Sizuoka, Tokyo, and Yamanashi which are surrounding prefectures of Kanagawa. No need for sympathy for blood suckers. Yup.

Nonetheless, I feel sorry for the animal who do not have any means of changing the course of climate. Or they could be wise enough not to fight a losing battle. They would be clever by adapting the changing climate and spreading their “home” … What will happen in 5 years’ time for Tanzawa and vampire leeches on boiling planet?

By the way, sweet osmanthus are at last opening in Yokohama. I think they are 2 weeks late. Still, it is the time when our ordinary suburbia is in sweet natural fragrance. Thank God, at least we have them flowering as previous years …

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/

Thinking the real meaning of Perpetual Summer: Summer 2024 in Kanagawa, Japan

 

In terms of earth’s revolution, tomorrow is autumnal equinox. Fall is supposed to conclude its run-up and our closet would be ready for jackets. Not this year. Yup. According to Japan Meteorological Agency, the final week of September in Japan could finally see the end of SUMMER, with temperature typical for the end of August until just a couple of years ago … Has the earth at last reached the tipping point of warming? I don’t know. One thing is for sure. Now the bugs in the forest are in full swing.

When I started posting this blog, activities in summer could not be done without insect-repellent. If that’s in the forests of Yokohama, I sprayed Icardin from head to toe. If it was for somewhere in and around of Tanzawa Mountains, applying leech repellent in lower limbs was the “Must.” We’re doing it now as before, but the power of the chemicals has been too powerful to be true this year. During high summer 2024, I had impression we did not have much problem with bugs. Instead, we’re welcoming bugs’ bites now in the equinox week. I guess bugs and leeches were baked in the hottest summer. They could not be active.

Normally uber-aggressive Black hornet. 
It was busy devouring nectar from Quercus acutissima
 in September.

Not only annoying mosquitos, but also birds were very subdued during high summer this year. Once in a month, normally in the first weekend morning, we’re recording fixed point observations of wild birds in Niiharu Citizen Forest. We had only a limited result this summer. Yeah, birds are descendent of cold blood dinos. They cannot control their own body against fluctuations of outer temperature. If it is too hot, their entire body is boiling. In such days, they stay somewhere in shade quietly. I imagine birds’ hot summer days would be like sick days of flu for us … Poor creatures. Our September observations this year only recorded crows and Chinese hwameis. It must have been a harsh and very LONG summer for birds. Are they OK?

Too strong sunshine …

Ditto for vampire leeches. Basically, they do not like dry environments. The way Tanzawa area received rain showers during summer 2024 may have affected the condition the bugs lived. Dry spells for several days, then, suddenly flood-level pouring came. The leeches must have confused. When we carelessly stomped in the bushes of Yadorii Water Source Forest this summer, we could often escape the attack of vampires. The shrubs were dry, and so was the soil. Not kind for leeches. i.e. All small creatures in the forests of Kanagawa Prefecture had difficult times this summer. They may find a respite now when the nights become longer than days. And, look! There comes prey (= we) for blood sucking!

I won’t be surprised if a vampire is in this photo, but …

So, in September the topic of conversations among forest volunteers finally becomes insects’ bites. It’s still damned hot, but (we hope) it’s milder now than in August. We notice bugs flying or crawling around us. Now’s the time for insect repellent to be useful. “I’m trying this new shirt made of high-tech material.” “What?” “It’s sold with a jingle the fabric itself had insect repelling function.” “Is it effective?” “I don’t know. And the fabric is too thick to wear during August. I have not tried it until now.” “Oh …” “ You know, I’ve also tried your kind of shirt before.” “Oh, then …?” “I was bitten by a black fly, and had a swollen arm. The fabric was too thin. The bug could insert his needle without directly landing on my skin.” “Heck” … It went like this. An earnestly important topic now! But just a couple of years ago didn’t we engage in such chat a bit earlier, during August, perhaps?

Parapodisma tenryuensis

Munch, munch … striped flea beetle

Meanwhile, the demanding mowing continues for months by now. In the weekend of equinox, we still made a heap of cut grass in Niiharu. I recalled my question to Lu Xun and really wanted to ask him how they mowed wild grass in China, if Chinese grass was “trampled upon and mown down, until it dies and decays as long as it lived it.” (My post on June 23, 2004) In fortnight, we will definitely feel the night is longer. Yet the wild grass is growing. Strange temperature …

Oh, so vigorous wild grass …

The Red Spider Lily is almost buried
in the other wild grass this weekend.
This is supposed to be the season of their one-man show …
 (; my post on September 29, 2023).

Summer Darter this weekend.
Yup, they fly around till the very late autumn for sure.
But they can be observed more commonly during summer.

A scene during a short break of mowing.

Even Japanese walnuts are still green.
They are supposed to be in harvest time!

There is also fun. Lots of beautiful butterflies are busy now recovering the lost opportunity. They stop wherever they find nectar and stay there longer. We can admire them with plenty of time, thinking if they are all right in these hotter September days. Summer is ending. We’re also exhausted …

Hestina assimilis is busy drinking from a sweat-drenched shirt
 from one of the seniors of Niiharu Lovers.
It needed salt, we guessed.
By the way, this butterfly is registered as
 an Invasive Alien Species in Japan.
 Basically, it is common in Southeast Asia and Continental East Asia.
 It suddenly appeared in Saitama Prefecture in 1995.
 In 2015 there is a record it was flying at the summit of Mt. Fuji.
 Experts are suspecting somebody
intentionally released the original brought from overseas.
Warming climate of Japanese megalopolis encouraged it to prosper.
This year, it was SOOOOOOOO ubiquitous in Yokohama.
Its lifestyle is like endemic Hestina persimilis japonica.
People are worrying it could compete ecologically
 and win over the natives.

A Straight swift on flowers of garlic chives

Beautiful Japanese oakblue

Nordstromia japonica is sleeping in the shade.

If you find a problem in the greenery of north-half of Yokohama, please make a contact with

Office for the Park Greeneries in the North
北部公園緑地事務所
Yokohama Municipal Government Green Environment Bureau
横浜市みどり環境局

Phone：045-353-1166
FAX：045-352-3086
mk-hokubukoen@city.yokohama.jp

Talking with Soil Creatures: counting soil animals in Yadoriki Water Source Forest やどりき水源林

 

Every July, we Forest Instructors for Kanagawa Prefecture do field research in Yadoriki Water Source Forest やどりき水源林. The main theme of this occasion is what kind of soil animals live underground of the Water Source Forest. We employ two approaches to collect tiny animals in the ground. One is collecting roughly 10cm deep dirt from 50cm*50cm square soil, sifting it by large sieve over a white plastic table cover, and inspecting the soil spreading over the cover to find out what comes out from the sieve. Another is using pitfall trap. 3 days before the research, we bury three medium-sized plastic containers with wide mouth. Each container has bites inside; chicken meat to lure carnivorous creatures, a banana for vegetarians, and for everybody crumbled kitchen paper drenched in brown sugar syrup. The opening of the boxes is at the surface level of the ground. It is covered by a lid with legs to shield the trap from pouring rain, but with wide enough gap for small living things visiting for bites. We make such instalments for two observation sites and go to see what’s inside 3 days after.

Collecting soil from 50*50

Three traps

Retrieved trap with chicken meat

This year, the team I joined was to check the soil creatures inside the fence before the toilet at the corner of the open space. The place is a mound made about 30 years ago when the water source forest was a commercial camping site. At that time, people made the heap there and planted seedlings of broad-leaved trees. They then enclosed the area by a fence in order to prevent deer came in and devour the baby trees. Now in 2024 surely we do not find droppings of deer inside the fence. But the trees remain lanky, and the entire ground is always dark as it is surrounded by tall coniferous trees. By simple guessing, we may expect there are lots of soil animals which in general do not like baking sun or drier soil condition … er, wait. Not so fast.

Surely, inside the fence is deer-free,
and rarely hosts vampire leech.
It’s a good place to install hammocks for nap.

First of all, there was an accident. We started our research from collecting the buried 3 boxes. In the box of chicken, there were lots of Anisodactylus signatus (in beetle family). Fine. In the box of syrup, there was not many bugs trapped. Syrup 3 days ago was almost dried up. The problem happened in the box of banana. This box was also almost empty, and above all, there was no banana, or the remnants of it. “Hmmmmmmmm. There must have been at least one thief.” “Indeed. It seems to me the thief came here early. May be immediately after we left this place. The box is so empty and clean.” “Wow.” “But how did it do it? The gap between the lid and the box is not wide, and it must have dug deep inside the box.” “No trace of pecking …” “It means the culprit was a mammal.” “But there is a fence!” “Somebody which is good at climbing up fences ...” Last year when we checked DNA from the water of Takigoh Fall 滝郷滝, near our soil study site, there were DNA bits of masked palm civet. It is a foreign species devouring commercial produce from farm fields. Also, the animal is good at climbing high, trees, roofs, etc. For it, penetrating inside the fence won’t be much problem. ***Sign*** We discussed how to make a lid of the trap from mammals. We have not reached the conclusion, but we must improve the design of the trap, for sure.

Empty bananas

Takigoh Fall.
Somewhere up there, masked palm civet is roaming.

Having said that, when we checked the number of families in the soil brought from the front forest for the toilet, it also was not much. Another location for the research was near the garage for forestry monorail. The number of creatures identified there this year was 53. The number we could identify from the artificial mound near the toilets was 45. Actually, such difference has been observed for several years.

Carrying collected soil for study

What’s there?

For example, here!
Geophilomorpha and earthworm.
Geophilomorpha can be found only in non-contaminated environments.
It’s good news we could encounter it.

Come to think of it, inside the deer fence in front of the toilets shows only a small number of fungi either. According to Dr. Taizo Nakamori (2022) for Yokohama National University, fungi is like a sweet shop for soil animals. People often misunderstand soil animals like worms make fallen leaves or twigs on the ground into nutrients for soil, like nitrogen. Nah. That’s the job done by bacteria, not soil animals. Of course, tiny bugs eat such leaves to survive. But they eat them and simply poop them afterword, which makes the fallen leaves into a smaller bit for bacteria to digest. Their contribution for soil creation is in this way. Fallen leaves are litter after the plants stopped supplying sugar et al from their photosynthesis. The level of nutrients in it is inevitably low, consisting of mainly cellulose = hard to chew. The soil creatures make do with this poor diet. However, if the soil has lots of fungi which will become mushrooms when the climate is right, the story is different. Fungi decompose plant litter with their enzyme and recompose the nutrients to become fungi. For soil animals, eating fungi allows them skipping their hard labor of chewing cellulose. When mushrooms come out, the soil animals swam such “candy” which is a mass of fungi hypha. They will move to the ground of mushroom. i.e. When there are lots of mushrooms on the ground, there will be lots of soil animals. If not much mushrooms found, the number of soil creatures would be smaller. 

* Taizo Nakamori, Soil Animals and Fungi, in Tomoyuki Shimano; Motohiro Hasegawa, and Yasuo Ogiwara (eds.) “The Topics of Soil Creatures,” 39-56, Asakura Publishing, Tokyo, 2022.

A mushroom we found in a previous fall inside the deer fence.

“Is it because the place is made of artificially brought soil?” “Possibly. But the construction was tens of years ago, wasn’t it?” “Yeah, the effect still continues, maybe.” “Oh, … hmmmmmmmmmm …” “Why?” It’s a mystery. There would be an explanation why the shady artificial mound does not show the same level of biodiversity as the next door natural soil. Curious.

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/