The type of rotan fish is a little unusual, most of its body is made up of a large head and a huge mouth, it is not for nothing that it is called a firebrand. To many, the appearance of rotan seems unattractive, but its taste properties can compete with any other more noble fish. Let’s try to understand all the nuances of the life of this fish predator, describing its appearance, habits and disposition.
Origin of the species and description
Rotan belongs to the ray-finned fish of the firebrand family, it is the only one that represents the firebrand genus. Rotan — perch-like fish, it is also called grass or firebrand. Somewhere closer to the second half of the last century, such a name as the Amur goby was attached to this fish. Of course, rotan looks very similar to a goby, but it is wrong to call it that, because it has nothing to do with their family.
Not many people know how to distinguish a goby from a rotan, so you should focus on this. The differences are in the ventral fins: in the grass weed they are paired, rounded and small, while in the goby they are fused into one rather large sucker.
Rotana was brought from the East. He perfectly took root in the new conditions, literally, having occupied many reservoirs, displacing other fish. Perhaps this happened because the firebrand is very hardy, unpretentious in food, one might even say illegible, the vitality of this fish is simply amazing. If there are no other predatory fish in the reservoir, then voracious rotans can completely kill roach, dace and even crucians. Apparently, that is why they are also called live-eaters.
Rotana is distinguished by its huge head and huge insatiable mouth, they occupy almost one third of the entire body of the fish. Rotan is unpleasant to the touch, because. his whole body is covered with mucus, which often exudes a not very pleasant aroma. In general, this fish is not large in size, a standard rotan weighs about 200 grams. Specimens weighing half a kilogram are very rare.
Rotana can be confused with a goby, but it differs significantly from other fish, having an unusual appearance, the features of which we will try to figure out.
Appearance and Features
The body of rotan is very massive, knocked down, but not long, it is densely covered with medium-sized scales in addition to mucus.
The color of rotan is very variable, but the following tones prevail:
- dark brown;
- dark brown;
- black (in males during spawning).
In water with a sandy bottom, the rotan has a lighter color than the one that lives in the marshlands. During the mating season, the males turn completely black (they are not called “firebrands” for nothing), and the females, on the contrary, become lighter tones.
The coloring of the firebrand is not monophonic, it has characteristic lighter spots and small stripes. The belly of the fish is almost always a dirty gray color. The length of the body of the fish can be from 14 to 25 cm, and the largest mass can be up to half a kilogram, although this is a rarity, usually rotan is much smaller (about 200 g).
An oversized head with a huge mouth equipped with teeth as small as needles is the calling card of this fish predator. By the way, the teeth of the firebrand are arranged in several rows, and the lower jaw is slightly elongated. They (teeth) have the ability to change to new ones at certain intervals. The bulging eyes of the fish are set quite low (right at the very top lip). On the gill cover there is a spine-like process, looking back, which is characteristic of all perciformes. A characteristic feature of rotan is its soft fins that do not have spikes.
Two fins are noticeable on the ridge of rotan, the rear of which is longer. The anal fin of the fish is short, while the pectoral fins are large and rounded. The tail of the firebrand is also rounded, there are two small fins on the abdomen.
Where does rotan live?
At first, rotan had a permanent residence permit in the Far East of our country, in the territory of North Korea and in the northeast of China, then it appeared in the waters of Lake Baikal, which scientists accepted as biological pollution of the lake. Now the firebrand has spread widely everywhere, thanks to its endurance, unpretentiousness, the ability to stay without oxygen for a long time, adaptability to various temperature conditions and their fluctuations, and the ability to live in heavily polluted waters.
Rotan is found throughout our country in various bodies of water:
- wetlands .
Now rotan can be caught in the Volga, Dniester, Irtysh, Ural, Danube, Ob, Kama, Styr. The firebrand takes a fancy to floodplain water bodies, between which it settles during floods. She does not like too rapid current, she prefers stagnant water, where there are no other predatory fish.
Rotan loves dark muddy waters, where there is a lot of vegetation. In those places where such predators as pike, asp, perch, catfish live in abundance, rotan does not feel comfortable, its numbers there are either completely insignificant, or this fish does not exist at all.
In the first half of the last century, a person launched rotans into reservoirs located on the territory of St. Petersburg, then they massively settled throughout the northern part of Eurasia, Russia and various European countries. On the territory of our country, the habitat of rotan runs from the border with China (Urgun, Amur, Ussuri) to Kaliningrad itself, the Neman and Narva rivers and Lake Peipsi.
What does rotan eat?
Rotans are predators, but predators are very voracious and insatiable, spending most of their time in search of food. Firebrands have very sharp eyesight, they are able to distinguish moving prey from afar. Seeing a potential prey, rotan follows it slowly, with small stops, helping itself only with small fins located on the abdomen.
On the hunt, rotan has tremendous calmness and equanimity, moving smoothly and measuredly, as if thinking about what maneuver to take, and his quick wit does not fail him. Newborn fry of rotan first eat plankton, then small invertebrates and benthos, gradually starting to eat like mature relatives.
The menu of an adult rotan is very diverse, it is not averse to eating:
- small fish;
Grasses do not refuse caviar and fry of other fish, which often causes great damage to its livestock. In small reservoirs, where there are no other predators, rotan breeds very quickly and can kill other fish, for which anglers do not like it. They do not disdain firebrands and all kinds of carrion, eating it with great pleasure.
Rotan often eats without measure, absorbing prey in huge quantities. Its huge mouth accommodates fish, the volume to match it. The gorged pot-bellied rotan almost triples in size, then it sinks to the bottom and can stay there for several days, digesting what it eats.
Cannibalism flourishes among rotans, when larger individuals eat their smaller counterparts. This phenomenon is especially developed where there are a lot of this fish.
It is worth noting that sometimes rotan is specially launched into a heavily stocked reservoir. For example, in a pond where crucian carp has become very bred and crushed, rotan reduces its population, thereby helping the remaining fish to grow to a more significant size. We can say that rotan is unpretentious in food and eats almost everything that it catches, literally overeating to satiety.
Character and lifestyle features
Rotana can be called an active, almost always hungry, and therefore aggressive predator. It would seem that he can adapt to any, even the most unfavorable conditions of existence. The unpretentiousness and endurance of rotan are simply amazing. Rotan remains alive even when the reservoir freezes to the very bottom. He also tolerates strong dry periods with success. This miracle fish avoids only fast currents, preferring secluded, overgrown, stagnant, often swampy waters with a muddy bottom.
Rotan is active all year round and continues to be caught both in winter and summer. Hunger overcomes him in any weather, his appetite falls slightly only during the mating season. If in winter cold many predators form flocks and set off in search of warmer places, then rotan does not differ in such behavior. He continues to hunt alone. Only severe frosts, leading to the freezing of a reservoir, can move rotans to unite in order to survive.
No ice is formed around such a flock of firebrands, because. the fish secretes special substances that do not allow it to freeze, it falls into a stupor (anabiosis), which stops with the first warming, then the rotan returns to normal life. Sometimes during wintering, rotans sink into silt and remain immobile for months. The same method of rattan is used during severe drought, being not only under a layer of silt, but also in a capsule of its own mucus, which helps them survive natural disasters.
All kinds of pollution also do not frighten rotans, even bleach and ammonia do not particularly affect them. In very dirty water, they not only live, but also continue to breed successfully. The survivability of rotan is amazing, in this regard, he was common even with an unpretentious crucian. Rotan can live for about fifteen years, but usually its life span is from 8 to 10 years. This big-headed predator is so exclusive and unusual.
Social structure and reproduction
Sexually mature rotan becomes closer to three years of age, spawning takes place in May-July. At this time, both females and males are transformed: the male turns into a noble black color, a certain growth stands out on his wide forehead, and the female, on the contrary, acquires a lighter color so that it can be easily seen in muddy water. The mating games can go on for several days.
In order for the rotan to start active reproduction, the water must warm up from 15 to 20 degrees with a plus sign.
The number of eggs spawned by one female reaches a thousand. They have a yellowish tint and a slightly elongated shape, equipped with a very sticky filament leg to firmly fix on aquatic vegetation, snags, stones lying on the bottom. For spawning, the female chooses a secluded place so that as many fry as possible can survive. The male becomes a faithful guardian, protecting the eggs from the encroachments of any ill-wishers.
Seeing the enemy, the rotan begins to fight, ramming him with his massive forehead. Unfortunately, rotan is not able to protect its future offspring from all predators. For example, with a large perch, he can rarely cope. In addition to security duties, the male performs the function of a kind of fan, fanning the eggs with the help of fins, because. they need much more oxygen than mature individuals. Thus, a current is created around them, and an influx of oxygen is carried out.
Despite the fact that the male takes care of the eggs so tirelessly, when offspring appear from them, he himself can eat them without a twinge of conscience, this is due to the struggle for the survival of the strongest and the practice of cannibalism among rotans. It is worth paying attention to the fact that the grass can live in lightly salted water elements, but spawns only in freshwater. The predatory breed of rotan is immediately visible, already on the fifth day after birth, the larvae begin to feed on zooplankton, gradually increasing the size of their prey and switching to the diet of adults.
Growing fry hide in dense underwater growth, because they feel which can become a snack not only for other predators, but also for their closest relatives, including their parents.
Natural enemies of rotans
Despite the fact that rotan itself is a voracious and always active predator, it also has enemies are available and do not dormant. Among them are pike, catfish, snakehead, asp, perch, eel, pike perch and other predatory fish. In those reservoirs where one of the listed predators is found, rotan does not feel at ease and its numbers are not at all large, in these places the firebrand rarely grows more than two hundred grams.
Do not forget that the rotans themselves eat each other with pleasure, acting as enemies of their own relatives. Naturally, the eggs and fry of rotan are the most vulnerable, which often serve as a snack for all kinds of water beetles, especially predatory bugs, which are difficult for even mature fish to cope with.
Of course, among the enemies of the rotan, one can also name a person who not only hunts for him with a fishing rod, but also tries to take him out of many reservoirs where the rotan has bred heavily. Many commercial fish suffer from rotan, which can completely force them out of their inhabited territory. Therefore, experts take a variety of measures in order to reduce the number of rotan in a particular reservoir, thereby protecting other fish. Scientists believe that if no measures are taken on this occasion, then there will be no one to catch on the bait except for rotan.
Population and species status
The population of rotan is numerous, and the range of its settlement has expanded so much that now the firebrand can be found in completely different regions. This is explained by the unpretentiousness, endurance and enormous vitality of this voracious predator. Now rotan has been ranked among weedy fish that threaten the population of other (more valuable, commercial) fish. Rotan has bred so much that now scientists are looking for more and more effective ways to reduce its numbers.
To combat rotan, measures such as the eradication of excess vegetation, the collection of caviar in places where fish spawn are used. To destroy rotans, special traps are used and artificially created spawning grounds are established, and chemical treatment of water bodies is also used. Any one method is not so effective, so they are used in a complex way, so that there is really a visible and tangible effect.
Oddly enough, but the amount of rotan restrains such a characteristic phenomenon as cannibalism. Usually, where there are a lot of firebrands, there are practically no other fish, so predators begin to devour each other, reducing their population. So, there are no threats to the existence of rotan, on the contrary, it itself poses a threat to the existence of many commercial fish, so people who have settled it so widely now have to fight tirelessly with it.
In the end, it remains to add although rotan looks unprepossessing, its appearance is unpresentable, but it has an excellent taste if it is prepared by skillful and experienced hands. Many anglers like to hunt for rattan, because its bites are always very active and interesting, and the meat is tasty, moderately fatty and very healthy, because rich in valuable nutrients, so necessary for any human body.