Lacedra is a commercial fish from the horse mackerel family, it is especially consumed in Japan, where it is highly valued. It is distinguished by thermophilicity, most of the fish sent to the shelves of stores is grown artificially, as a result of which the damage to the natural population is low.
Origin of the species and description
Ancient creatures resembling fish and considered their ancestors lived on our planet more than 530 million years ago. The most famous of this group of jawless creatures is pikaya: a very small (2-3 cm) animal that did not yet look like a fish and moved in the water, bending its worm-like body.
Or pikaya, or creatures related to it, can be the ancestors not only of fish, but of all vertebrates in general. Of the later agnathans, which are close in structure to modern fish, the best known are conodonts. This is a diverse group of protofish, the smallest of them grew up to only 2 cm, and the largest – up to 2 m. They acquired an exoskeleton.
It was the conodonts that became the ancestors of the jaws, and the appearance of the jaw was the most important difference between the first fish and their ancestors. It was possessed by placoderms that lived on Earth in the Silurian period. During this, as well as two subsequent periods, fish reached a large species diversity and began to dominate the seas of the planet.
But most of these ancient species died out at the beginning of the Mesozoic era, and the rest at its end. They were replaced by new species, and some of them still exist. However, the scad family, to which the Lacedra belongs, appeared later: after the Cretaceous-Paleogene extinction, which marked the beginning of a new era. Lacedra themselves appeared among the first in the family, at the beginning of the Eocene, 55 million years ago. The species was described by K. Temminck and G. Schlegel in 1845, received the name Seriola quinqueradiata in Latin.
Appearance and features
The Lacedra is a fish quite large, it can grow to a maximum of 150 cm and reach a mass of 40 kg, but for the most part they catch specimens weighing 5-8 kg. Its body shape is torpedo-shaped, laterally compressed. The fish is covered with small scales, and its head is slightly pointed.
The color of the fish is silvery with a bluish tinge. The back is slightly darker, and the fins are olive or yellowish. A distinct yellow stripe runs through almost the entire body, starting from the snout itself.
You can also distinguish the yellowtail from other fish by the fins. On the first dorsal rays are short and prickly, there are only 5-6 of them, and all of them are connected by a membrane. There is a thorn in front of him. There are much more rays on the second fin – 19-26, and they are soft. The long anal fin has both a few hard rays and a lot of soft ones.
The most important feature of the lakedra for humans is that its meat is very tasty, similar to tuna. It is reddish in color, can be used both fresh (the Japanese make sashimi, sushi and other dishes from it) and processed. It becomes lighter when exposed to high temperature.
Interesting fact: Most of the lakedra for sale is raised in captivity, while the meat of wild fish is valued more because its diet is more varied, and therefore it is tastier. As a result, the difference in price between sea-caught and farmed fish can be as much as 7-10 times.
Where does the yellowtail live?
This species is widely distributed both off the eastern coast of Asia and further east, in the open ocean.
The main areas of its catch are coastal waters near:
- Kuril Islands.
Lacedra actively migrates, but usually moves over short distances. Depending on the population, migration routes may vary. The largest or, in any case, actively harvested population spawns in the East China Sea, but from there, almost immediately, young fish swim north.
Then they spend the first few years of their lives near the island of Hokkaido. In the summer, when the water warms up, the yellowtail swims further north, to the shores of Sakhalin and Primorye. In winter, it returns to the shores of Hokkaido – this fish is quite thermophilic. During migrations, it follows large schools of fish, which it feeds on, like anchovies or sardines. Such migrations continue for several years, by the age of 3-5, the yellowtail swims south, to the shores of Honshu and Korea, some swim further south, but they have the highest concentration of this fish.
In addition to seasonal migrations, schools of yellowtail they often make relatively short ones, simply moving after schools of smaller fish and feeding on them along the way. Because of this, they are often caught when fishing for other fish, for example, with mackerel or anchovies, as bycatch, a lot of the following lacedra catches.
Now you know where the lacedra is found. Let’s see what this fish eats.
What does yellowtail eat?
Only the newly born Lacedras eat plankton, then, growing up, they gradually begin to eat more and more prey. In food, this fish cannot be called particularly picky: we can say that it devours any living creature that it can catch up and eat. Adult fish, growing to a considerable size, can eat a lot of different prey, mainly smaller fish – and do it successfully.
Among the most frequent victims of this fish:
- sardine ;
- fry and roe of various fish.
Lacedra hunt in packs, surrounding the school of prey from all sides and gradually squeezing the ring. Fleeing from them, small fish try to spread in different directions, often even jumping out of the water – from above and from a distance it may seem that the water is boiling from the abundance of jumping fish. This activity attracts the attention of the birds of prey, which contribute to the chaos: they dive and try to catch jumping fish. Sometimes people, seeing such a cluster, go to fish there – so the yellowtail can turn into prey.
In captivity, the yellowtail is fed with a mixture of meat of low-value fish species. It receives the essential vitamins it needs and grows rapidly on this diet – the ease and speed of cultivation has made it one of the main cultivated species in Japan.
An interesting fact: With artificial breeding, fry are seated in special cages according to the time of their appearance, as a result of which the larger ones cannot eat those that are smaller – and this is the main cause of death of a newly born fish. In addition, they are not threatened by any predators – as a result, ten times more fish survive to adulthood.
Peculiarities of character and lifestyle
Lacedra leads approximately the same way of life as most of the other scad fish. This fish lives in large flocks: it is more convenient to hunt this way. In one place, the flock does not stay for a long time, constantly moving either in search of schools of smaller fish that can be eaten, or following such a school.
Swims quickly, can catch up with almost any fish that is inferior to it in size. Due to its solid weight and body shape, it cuts through the water well, and therefore hunts especially successfully in dense layers of water, which slow down small fish. It has a swim bladder, so it can swim far into the open ocean.
But it is often found along the coast, in particular, there is a great chance that it will be possible to find it without swimming far into the sea, sometimes even near the coast, at dawn. Lacedra at this time often swims very close to capes and islands in search of prey. They fish for it since the morning.
Sometimes the yellowtail is mistakenly classified as a tuna, because it resembles them both in its appearance and behavior, and it feeds mainly on the same fish – which means that it can most often be found in the same places. But yellowtail with tuna are not close relatives. You can distinguish tuna by crescent-shaped fins: the lacedra does not have them. This fish does not live long, 10-12 years, a long-lived individual is considered to have reached 15 years, and there are few of them.
Social structure and reproduction
By 3-5 years, the Lacedra becomes sexually mature and goes to the first spawning – then it will be repeated annually. Spawning begins in May-June and stretches until the very end of summer: in order to spawn, fish need warm water and good weather, so the process can take a long time. Therefore, the yellowtail goes to the very south of its range to lay eggs: to the Japanese islands of Kyushu and Shikoku, as well as to the coast of South Korea. Moreover, she goes not just into the sea that washes these areas, but directly to the very shores: females throw eggs at a distance of 100-250 meters from the shore directly into the water column.
Nearby at this time there are males releasing milk, and thus fertilizing caviar. The eggs themselves are very small, even less than a millimeter, but each female releases hundreds of thousands of them, and does not die. Not all are fertilized – the remaining unfertilized eggs serve as food for those who are more fortunate.
However, the fertilized ones are also eaten by fry that hatched earlier: the incubation of eggs lasts about 3.5-4 months, and therefore, if two females went to spawn in approximately the same place, the fry that appeared earlier will simply eat all the eggs of the second female. Fry live in the water column, but close to the shore, not sailing far from the place where they were born. They feed not only on caviar and plankton, but also on each other – only the strongest and fastest survive, especially since they also have to escape from numerous predators. They also eat a lot of algae.
They look like an adult fish from the very first days, grow very quickly at first and become more and more formidable predators from potential prey: they demonstrate the corresponding habits from the very first days of life. With artificial breeding, they grow to a selling weight of 3-5 kg in just a year, in natural conditions it takes twice as long – but the maximum weight in them is higher.
Lacedra’s natural enemies
For adults, there are few threats in the sea: they are too large to become prey to marine predators. The main exception is sharks, there are quite a lot of them in those seas where the lacedra live, and they eat everything that is in sight, and they especially love large fish.
Despite this, if the lacedra managed to grow , its chances of living all the measured time and dying of old age increase by an order of magnitude, since there are much more threats to young individuals: they are of interest to both large predatory fish and birds. And the smaller they are, the more predators threaten them.
Accordingly, fry and eggs die the most. Both are eaten by predatory fish – mostly small and medium, other fry, including relatives, adults of the lakedra. Many species that will become the prey of the grown yellowtail eat its fry and caviar – for example, herring and sardine.
Because of all this, only a very small percentage of the eggs that were once swept out become adult fish. After that, their main enemy will be people who actively catch this fish; although most of the lacedra sold in stores is grown artificially, and not caught at all.
There are much fewer threats to her in captivity, because she is reliably protected from predators. But still, these threats exist: these are parasites and diseases, especially dangerous bacterial damage – vibriosis. These threats are also present in the fish’s natural habitat.
Interesting fact: In Japan, it used to be believed that a person becomes older on New Year’s Day. This was celebrated with a festive fish dish called “toshitori zakana”. If in the eastern part of Japan they used salmon for this dish, then in the western part of Japan they used lacedra. This tradition has continued into modern times.
Population and species status
Nothing threatens the lakedra population: although industrial fishing is underway, its volumes have significantly decreased due to the fact that a lot of this fish is grown artificially. And even in those years when the catch reached peak values, there was no significant decrease in the population.
The largest number of this fish is concentrated in the East China Sea off the coast of Japan and Korea. The population of the yellowtail is stable, it is mainly limited by the amount of food in the habitats of the fish. There is less data on the abundance of this fish in the depths of the Pacific Ocean, where it is practically not caught.
They catch lacedra mainly at a small distance from the coast, the total catch in all countries reaches several tens of thousands of tons per year, most falls on Japanese ships. Previously, in some years, the catch reached 130-180 thousand tons.
It is artificially grown both in cages and in fenced offshore areas. The main share of fish farms where lacedra is grown is in Japan and Korea, the total production of this type of fish on them reaches 150 thousand tons per year. Increasingly, production is intensifying in China and Taiwan, where conditions are also suitable.
Interesting fact: The Japanese have come up with many names for this fish – they differ depending on the region and the age of the yellowtail. So, in the east, in Kanto, the smallest choice is called wakashi, slightly grown up – inada, then warasa, the largest – buri.
In the west, in Kansai, the names are completely different – tsubasu, hamati and mejiro, only the last one coincides – storms. Adults caught in winter are called kan-buri and are believed to become tastier after each snowfall.
Lacedra is one of the rare species of fish that does not suffer from active fishing, and is therefore very valuable. In addition, it is very easy to breed in captivity, which makes it even more useful. In Japan and Korea, it is highly valued, and in fact, in terms of taste, it is comparable to other delicacy, but much more vulnerable species, such as salmon.