FOR AGES 3 YEARS TO 18 YEARS
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Kidadl provides inspiration to entertain and educate your children. We recognise that not all activities and ideas are appropriate and suitable for all children and families or in all circumstances. Our recommended activities are based on age but these are a guide. We recommend that these ideas are used as inspiration, that ideas are undertaken with appropriate adult supervision, and that each adult uses their own discretion and knowledge of their children to consider the safety and suitability.
Kidadl cannot accept liability for the execution of these ideas, and parental supervision is advised at all times, as safety is paramount. Anyone using the information provided by Kidadl does so at their own risk and we can not accept liability if things go wrong.
The ayu fish, scientifically known as Plecoglossus altivelis, is a fish species that is the sole member of the Plecoglossus genus and belongs to the Plecoglossidae family. It is also known as the ai or ayu sweetfish in Japan because of its flesh's sweet taste. It is a highly popular food in East Asia. This sweetfish (Plecoglossus altivelis) is a delicately flavored fish that is grilled and skewered over fire and is considered to be one of the most delicious river fish. It is indigenous to East Asia and occurs across the northwestern Pacific Ocean near the Hokkaido coast in Japan, and spreads southwards to China, the Korean Peninsula, Vietnam, and Hong Kong. It can be found inhabiting rivers that are very clean and fast-flowing. It is one of the most important fish species among Japanese freshwater fisheries. Increasing environmental awareness among Japanese people is helping this fish, as the habitats of this fish in Japan have been disappearing due to dam-building.
It is a fish species that is quite small in size and ranges between 6–12 in (15.2-30.4 cm) in length. The unique ayu sweetfish is olive or light yellow in color and is distinguishable from other fish due to its sail-like dorsal fin, teeth arrangement, and ridged tongue. It feeds upon water weeds, algae from rocks, crustaceans, sponges, worms, and aquatic insects. Their teeth marks can be spotted easily on the rocks they fed upon. Japanese fish of this species will attack any intruder and this behavior of the ayu sweetfish is exploited by some Japanese anglers who use this behavior to lure and catch the fish. This tends to work like a charm with the fish getting caught easily. This fish does not have a long lifespan, and adults might only live for two to three years. Adults swim down to the river in March to spawn. The larvae of the Plecoglossus altivelis enters the sea and preys upon plankton during the winter, and then in spring, it returns to the river. Keep reading to get to known more exciting facts about the unique ayu fish!
If you enjoyed reading our ayu fish facts, you must check out our bumphead parrotfish surprising facts and shortfin mako shark fun facts as well!
The ayu fish, Plecoglossus altivelis, is a fish that belongs to the family Plecoglossidae and is the sole member of the Plecoglossus genus. Smelts are relatives of the ayu sweetfish as both of them belong to the same Osmeriformes order. The sweetfish (ayu or ai) is a marine animal that is eaten as food and has an exquisite taste when seasoned with sea salt. It is eaten commonly in the summer season, particularly in the Asian continent.
Plecoglossus altivelis fish belong to the class Actinopterygii.
The population of this species has not been evaluated yet. However, we do know that their population trend is declining. The major threats that they face are fishing, harvesting, dams and water management, and pollution
This fish is indigenous to East Asia and can be seen across the northwestern Pacific Ocean near the Hokkaido coast in Japan. Its range spreads southwards to China, the Korean Peninsula, Vietnam, and Hong Kong. Some populations also reside in the lakes of Japan, like Lake Biwa. This species has also been introduced in Taiwan. It can be found inhabiting rivers that are fast-flowing. It is a migratory sea animal that migrates upstream in clear river waters in order to spawn.
The typical ayu fish habitat varies as it matures. It is an amphidromous creature that migrates to freshwater rivers and lakes with clean water from coastal marine waters after it matures. As Japanese streams are not of great depths, this species is found in shallow waters only.
It can be spotted swimming in small schools at the river mouth.
It lives for two to three years. In a river, they are likely to only survive up to one year but in a lake, they can survive for two to three years!
Adults swim to the river in March (spring) to spawn. The larvae of this species swim to the ocean where they remain throughout winter and feed on plankton. They return in spring to the river. A few survive for two to three years and are able to spawn each year, while others spawn only once. When breeding this fish in captivity, scientists have successfully produced a transgenic ayu that carries a gene from a rainbow trout which helps the ayu to be two times heavier and live 1.3 times longer.
The conservation status of the ayu has not been evaluated by the IUCN yet. It is officially listed as Data Deficient. This fish is threatened by fishing, harvesting, dams and water management, and pollution. The ayu is classified as threatened in Taiwan. Interestingly, these Japanese fish are extremely territorial and will attack any invader. This trait of this species is exploited by Japanese anglers to catch these fish and it works really well as these fish are caught easily. Tame cormorants are used in Japan to catch ayu fish. Other methods for capturing ayu fish are fly fishing, using a fish trap, and fishing with a decoy.
This fish is quite small in size and ranges between 6–12 in (15.2-30.4 cm) in length. The unique ayu sweetfish is olive or light yellow in color and is distinguishable due to its sail-like dorsal fin, and ridged tongue. Its teeth are arranged at the side of the jaw on saw-edged plates.
*Please note that this image is of a delta smelt, a close relative of the ayu fish. If you have a picture of an ayu fish, please let us know at [email protected]
These sweet-tasting fish that are very common in Japan are quite cute and attractive, especially when young. Their coloration is quite interesting as well.
Like their relatives, they communicate using motion, electrical pulses, bioluminescence, and chemicals.
It is quite small in size and ranges between 6–12 in (15.2-30.4 cm) in length. It can grow up to the same length as the rockmover wrasse!
The speed of juveniles can range between 0.5-1 m/s (1.8-3.6 kph).
It ranges between 0.01-0.82 lb (4.5-371.9 g) in weight. The lower end of their weight range is the same as the weight of a female rainbow shiner.
Males and females of this species do not have specific names.
A young ayu sweetfish is called a fry!
The ayu fish feeds upon water weeds, algae from rocks, crustaceans, sponges, worms, and aquatic insects found in rivers. The ayu fish itself is one of the most highly prized food fish. This food fish is consumed in the summer season.
Yes, the ayu is very territorial about its feeding sites and will attack any creature who enters its territory in the river or sea. One sweetfish defends 107.6-215.3 ft2 (10-20 m2). Some anglers in Japan exploit this territorial trait. They introduce a live ayu on a hook into another ayu's territory, leading to the territorial ayu attacking the introduced ayu. These fish are largely harmless to people.
There are no known instances of the sweetfish being kept as a pet. However, given their territorial nature, an ayu should not be kept in a tank with any other fish.
Many people say that the ayu emanates a watermelon-like fragrance!
The term 'endemic' is used to refer to a creature that is found in one specific area regularly. The ayu is endemic to East Asia.
The ayu, Plecoglossus altivelis, can be seen across the northwestern Pacific Ocean near the Hokkaido coast in Japan, southwards to China, the Korean Peninsula, Vietnam, and Hong Kong.
Here at Kidadl, we have carefully created lots of interesting family-friendly animal facts for everyone to discover! Learn more about some other fishes from our salmon interesting facts or rock hind facts for kids pages!
You can even occupy yourself at home by coloring in one of our free printable Ayu Fish coloring pages!
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At Kidadl we pride ourselves on offering families original ideas to make the most of time spent together at home or out and about, wherever you are in the world. We strive to recommend the very best things that are suggested by our community and are things we would do ourselves - our aim is to be the trusted friend to parents.
We try our very best, but cannot guarantee perfection. We will always aim to give you accurate information at the date of publication - however, information does change, so it’s important you do your own research, double-check and make the decision that is right for your family.
Kidadl provides inspiration to entertain and educate your children. We recognise that not all activities and ideas are appropriate and suitable for all children and families or in all circumstances. Our recommended activities are based on age but these are a guide. We recommend that these ideas are used as inspiration, that ideas are undertaken with appropriate adult supervision, and that each adult uses their own discretion and knowledge of their children to consider the safety and suitability.
Kidadl cannot accept liability for the execution of these ideas, and parental supervision is advised at all times, as safety is paramount. Anyone using the information provided by Kidadl does so at their own risk and we can not accept liability if things go wrong.
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