Jimbeizame: Whale Shark

There are so many sea animals on Earth, for example, fishes and mammal. Rhincodon typus is the biggest of fishes on earth. It is called a Whale shark in English.

In Kaiyukan, Osaka

It is a most body length of about 13.7m and width of about 1.5m. The figure is a spindle-shaped, flat head and the teeth are 300 to 350. The skin tissue is thick, and the thickness is about 10cm. Tail fin of the adult are usually crescents. However tail fin of the young does not stand out the lower part, and have the feature with large only upper part. The color is light yellow into white check in body, is white in stomach but without stomach, is ultra marine. Marking of the whale shark is seen personality each individual. It is so useful to individual recognition when we observe. The whale shark is very timid and a quiet-looking. It acts basically alone however rarely by the flock. Female of the whale sharks tend to stay in a specific sea area, on the other hand male of them wander a wide sea area.

Genus name is Rhincodon and species name is typus. Rhincodon typus was classified and described by Andrew Smith biologist British based on the specimen captured in the Table Bay in Cape Town in South Africa in April, 1828. It is guessed that Rhincodon typus was born 60 million years ago.

Whale sharks live in a subtropical, tropical, temperate zone in the surface sea area around the world and wander. They are seen also in the vicinity of the mouth of river, a lagoon, a coral reef and among bays.

The whale shark makes small ecosystem. Why can this be said? Whale sharks are filter feeding and eat plankton. Small fishes also are eating it. Medium fishes flock for eating small fishes. Large migratory fishes flock for eating medium fishes. Namely, the whale shark forms a small ecosystem by one individual. People thought that it was a lucky of good catch between fishermen. So, Japanese does not eat it. But it is said that the whale shark had been decreased enough to put on the Red List of endangered species. Because a developing people that suffer from a food shortage hunts excessively. Once it had been believed that the whale shark was oviparous. But it was turn out that it was viviparous in 1995. After the spawn hatches in the interior of the womb, the fry is given birth while having grown up from 40 to 60cm. It matures in about 30 years and lives at about age of 70. We do not know breeding of the whale shark much. But we know that their propagating power is low. And today it is said that the protection of the whale shark is important. Otherwise, it might be exterminated.

We can see the whale shark in Ashizuri Cape in Kochi. It wanders to Tosashimizu from June to September. Or always are able to see it at Kaiyukan in Osaka, Tyuraumi Aquarium in Okinawa and Iburi center in Tosasimizu. In Iburi center, the living thing to exhibit in Kaiyukan is collected, bred and the surveillance study of the surrounding ocean area is done.

Kawauso: River Otter

The scientific name of the locally extinct otter is Lutra lutra whiteleyi. Taxonomy is Animalia, Chordata,Vertebrata, Mammalia, Carnivora. It inhabits Australia, waterside and the sea of a whole world except New Zealand. It is good at swimming and adapts myself to life in the water. It is an extinct species in the wild in Kochi. But it can be seen in Wanpak Kochi. Continue reading Kawauso: River Otter

Skipjack Tuna

Skipjack tuna is the English name. Japanese name is katuo. And scientific name is Katsuwonus pelamis. And there are seasonal Japanese namea, that for example is modorigatuo and kudarigatuo. The Skipjack tuna is designated as Kochi prefecture’s fish.

Skipjack tuna is eaten as tataki and sashimi in Kochi. And pole-and-line fishing of Skipjack tuna in Kochi is famous. And also raw Skipjack tuna in Kochi is very famous all over the country.

Skipjack tuna can grow to a body length of 1m of large size and to a body weight 18kg. Its form is spindle-shaped that has low hydrodynamic drag. Section is nearly ring shape.

Skipjack tuna belong to katuwonus of scombridae of scombroidei of perciformes of actinoptergii of vertebrate of chordate of animalia.

There are some varieties of scombridae; the striped bonito (Sarda orientalis), the Skipjack tuna (Katuwonus pelamis), the kawakawa (Euthynnus affinis).

Striped bonito is smaller than Skipjack tuna, but has a lot more of teeth than skipjack tuna, and also back color is different each other. Striped bonito’s color is blue, but Skipjack tuna’s color is deep indigo. The kawakawa, which range at over a large area of the tropical zone subtropical zone of the Indian Ocean, is heavier and has bigger withers weight than Skipjack tuna.

Skipjack tuna’s rage is the temperate zone and the tropical zone area of sea all over the world. ;It exists between the north latitude of 40° and the south latitude 40°of the equator’s both sides. Skipjack tuna visit each the Pacific Ocean side to the south of Hokkaido and Kyushu west coast at Japan. Skipjack tuna’ rage is very large, so discovery skipjack tuna’s migration course is very difficult.

As the above-mentioned, Skipjack tuna is living at temperate and tropical zone. This reason is that Skipjack tuna had a liking for water temperature 17~30°. Principally Skipjack tuna swim by school at sea surface of coast confine.

Skipjack tuna’s back body color is deep indigo and abdominal color is silver white of plain. This back and abdominal color is defense method to so-called counter shadowing. In that connection let me say that a lateral stripe come up to the abdominal when it is excited, and when it die , a vertical stripe and disappear a lateral stripe rise up to the abdominal.

Skipjack tuna is flesh-eating fish. They eat small size fish, crustaceans and cephalopoda. And they are migratory species of fish, so they move during the season, in other words, they goes up north in summer and go down south in autumn.

Usually Skipjack tuna swim at 25~50 kilometers an hour, and at times they swim about 100 kilometers an hour. But they die when they stop swimming. The reason is that skipjack tuna get a lot of oxygen from gills while they swim at high speed. So they experience oxygen shortage when they stop. Skipjack tuna stand higher rank of food chain, but t hey make large school so-called nagura, and play group action.

Skipjack tuna migrate along the Japan Current, so we can see at open sea of the Pacific Ocean (the Japan Current,) in early in summer to autumn in Kochi.

Ruddy Kingfisher

“Akasyoubin” are kind of kingfisher and range over the forest and can be seen as a summer bird In Japan. Because they have a red bill like fire and red body, they are called “fire bird”. Then their English name is “Ruddy Kingfisher” and scientific name is “Halcyon coromanda”. Though their bodies and legs are red, they have the vertical lines of cobalt blue on waists. Their length is about 27cm. Continue reading Ruddy Kingfisher

Midorigame: Common slider

In Japan,Midorigame are sold in the stall at the festival. They are sold in the pet shop, and kept at a lot of homes. Midorigame in Japanese is called Common slider in English. Common slider of the scientific name is Trachemys scripta.Trachemys means Akamimigame in Japanese. In other words, Midorigame is Akamimigame. Continue reading Midorigame: Common slider

Autumn Darter

Typically red dragonfly refers to dragonfly belonging to Libelluidae Sympetrum,
but in the narrow sense it may point only to Akiakane. It is one of the most of popular dragonflies, and the name means of color and is found in fall. Other names of red dragonfly are Akanetonbo, Akane, Akanenba and Akatonbou. It is also called Tougarashitoubo and Kaminaritonbo in Tohoku. Continue reading Autumn Darter

Cabbage butterfly

Cabbage butterfly can be compared to other butterflies such as swallow tail etc. Swallow tail is bigger than cabbage butterfly, length is 80~120mm. Cabbage butterfly is about 55mm. Swallow tail is green, yellow and black spots color while cabbage butterfly is wing color is white but reverse side is thin black color. Front wing point is black and front wing and back wing have two black spots. Their eyes have compound eyes and heads have club feeler. Continue reading Cabbage butterfly

Wild boar

Wild boar is classified as Vertebrata Mammalia Artiodactyla Suidae Sus Scrofa. And they are one of popular mammals in Japan. They have 16 kinds in world, for example, “Babyrousa” which lives in Indonesia Sulawesi; “Phacochoerus” which called “Iboinosisi” in Japan, which lives in Africa and “Sus” is group which belong Wild boar. They are the ancestors of pig, so their character is similar. In Japan, two kinds boars exist, “Japanese wild boar” (S. scrofa leucomystax) lives in Honshu, Shikoku, and Kyushu. “Ryukyu wild boar” (S. scrofa riukiuanus ) which is called Yamashisi or Yamanshi- lives in Ryukyu Islands. Continue reading Wild boar


Insects are many many species, for example butterfly, moth, dragonfly etc. Mantises belong to the class insect. We think they evolved from cockroaches. They have scythe and are oviparous. Their head is triangle with compound eyes. Feelers are two and short. Also they have wings– there are front wing and back wing. The back wing is thin and clear. Ground mantises are degenerate and they can not fly. They menace to other animals. Continue reading Mantis