The weather has been erratic lately – we’ve had glorious days with the maximum in the mid- to high- teens, and cold, wet and miserable days. The ground is covered with fallen leaves, only a few persimmons remain on my tree, and the days are becoming ridiculously short.
The azure-winged magpies are making their presence known with their calling out to each other and squabbling over fruit, but most other wildlife has switched off. The only praying mantises I’ve seen recently are dead ones, only a few jorogumo are left alive, and the vines that turn local forests into jungles in summer are rapidly dying and rotting.
I’ve also noticed that the number of visitors to Wild in Japan has petered off a little, but that my posts on raccoon dogs and snakes still seem to be the favourites… time to write about a snake!
I mentioned the Japanese keelback (Amphiesma vibakari vibakari) in my previous post, and would like to talk more about this fascinating animal. (I wanted more time to look at the specimen exhibited at the zoo, but got dragged away by the kids)
The Japanese keelback or Asian keelback is one of Japan’s smallest snakes. It has a natural range from Hokkaido to Kyushu and the immediately surrounding islands. A subspecies (Amphiesma vibakari danjoense) is found only on Oshima Island, Nagasaki Prefecture, while a third subspecies (A. v. ruthveni) is found in parts of China, Russia and the Korean Peninsula.
Growing to a maximum length of between 40 and 65 cm, the Japanese keelback feeds mostly on small fish, tadpoles, small frogs, and worms. They live in forests, and prefer areas around water – not at all surprising considering its diet. Japanese keelbacks are crepuscular – active around dawn and dusk – although they may become active during the daytime following rain.
Part of my interest in this snake was inspired by its local name, hibakari (日計 or sometimes 日量), which could be translated as “the measure of day” or “that day only”. Just as the tiger keelback was long thought harmless when it in fact possesses some of the most potent venom of any Japanese snake, the Japanese keelback was once believed to be venomous; a bite would cause the victim to die by the end of that day – hence the name. The Japanese keelback, in fact, does not possess venom.
I hope to get some photos to add to this post some day in the not-too-distant future.