Early last month, I had a chance to have a personal lesson with one of the rangers from the Wild Bird Society of Japan. They are keepers of Yokohama Nature Sanctuary 横浜自然観察の森 (; my post on January 22, 2016) and has done continuous survey of the place, especially for birds. The day was for one of the two regular line censuses per month. They very kindly allowed me to learn their way of doing on site. The route of the research is the same for these 30 years in the Nature Sanctuary. It makes possible for the Society to trace long-term changes of bird life in the South Forest of Yokohama. That early morning, very quietly I walked with Mr. Nakazawa for Wild Bird Society. We each carried binocular, recording forms and a map of the census route. First, we record the date, weather, humidity, etc., before starting the research, and wrote down the time when we began walking. All are vital info for the study … It’s a slow 1.5 hours walk, like 1-2km /h. The way for the research goes like this:
(1) Listen carefully the voice of birds coming within 50m radius of a researcher, I mean,
(2) Make it certain from where that voice comes, North, South, East, West, high, low, etc.
(3) Identify the species of the voice.
(4) If possible, use binocular to identify visibly the holder of the voice.
(5) Record the place and time we find the bird, then jot down species, number of individual, and if possible, male, female, adult, kids, what it was/they were doing etc.
After returning to the visitor center, we summarized our result in a standardized spreadsheet that makes further research easier. Mr. Nakazawa said “In this way, we accumulate the data and study the results several times a year. It can help to update our policy for nature conservation movement.” Indeed.
 |
| Early
morning in May for Yokohama Nature Sanctuary |
It was a very thrilling experience, but difficult one. Inside the forest was dark and birds were moving very quickly from bough to bough. At least for me, seldom came a chance to use a powerful binocular the Society kindly lent me. The main way to find a bird was by listening. Mr. Nakazawa said “Japanese tit has really many voices and ways to sing or call. So do the other birds. The only way to improve the identification is learning-by-doing. Let’s listen …” OK. We recorded not only tits, but crows, herons, swallows, brown-headed thrushes, brown-eared bulbul, woodpeckers, etc. etc. Since then, I became a sort of sensitive for bird voices. I even woke up at 4:30 when a Chinese hwamei declared its territory victoriously in our garden. What, what, what is it this early!!!?????
Actually, since last January it became a secret boom among some Kanagawa Forest Instructors intently listening bird “songs.” The beginning was a TV, called Science Zero series of NHK. On December 6th, 2021, they aired a special for the research by Dr. Toshitaka Suzuki of Kyoto University. He discovered Japanese tits have language with grammar. For example, according to Dr. Suzuki piercing JAAA JAAA screech of Japanese tits are emergency warning among them when they saw their predator … He published his research in Nature Communications, Current Biology, PNAS, Philosophical Transactions of the Royal Society B, etc. The tele was exciting, and we talked about it for months. A senior instructor actually did a mini-experiment as Dr. Suzuki. “You see? I was busy cleaning up bamboo forest and laid around the ropes over the ground to tie up the thinned bamboo branches. Then I noticed a tit was screeching ‘JAAAAA, JAAAA, JAAA.’ Soon the other Japanese tits gathered around me and started huge chorus of JAAAA! They mistook straw ropes for snakes and alerted each other their perceived danger. So, I pranked on them by coiling the ropes around the bamboos. Normally silent bamboo forest became a heavy metal concert!”
Naomi is a peace-loving person. I haven’t done such mischief for jumpy tits. Then, one early morning, I washed my forestry belt covered by dust and hung it on the backrest of a chair in the garden. I then returned kitchen for breakfast. Over my coffee, I noticed normally serene morning garden turned noisy with JAAA JAAA voices of Japanese tits. I returned in the garden and found out tits were surrounding the belt from the roofs. Oh, sorry. It’s a bit rude way of arranging a garden … Sure, tits are talking each other. Can we be multilingual to understand their chat, just like Dr. Dolittle?
 |
| It’s
not a snake. |
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 Creative Environment Policy Bureau
横浜市環境創造局
Phone: 045-311-2016 FAX: 045-316-8420
No comments:
Post a Comment