Fish and other aquatic creatures

Nereid, sea worm: description

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Nereis is another miracle that mother nature gave us. According to one of the legends, this creature was named after the Greek sea god Nerea, who in his whole life gave birth to fifty daughters-nymphs of extraordinary beauty. Apparently, the appearance of the worm is somehow similar to these mythical characters. But if you increase it many times, you can immediately recognize it in the nereis of the Chinese dragon. The same mustache, incomprehensible drawings throughout the body, the whole back is covered with thorns.

Nereid - Worm: Description of Appearance

Where does this species live? At the bottom of the sea live Nereids. These are not those who are called the daughters of the king of the sea in ancient Greek mythology. These are ordinary worms. The nereid polychaete worm belongs to the annulate.

His body consists of many rings, like we all know the earthworm. Nereid is a worm with a serpentine body structure. It has a head, metamerism (torso), anal lobe and lobed-like limbs. On the head of the Nereid there are eyes - two whole pairs. Also on the head section of the worm there are tentacles, two-segmented palpi. The extremities of the Nereid are littered with a multitude of bristles (hence the appearance of a polychaeta), with which it easily moves along the seabed at a speed that is good for the worm.

Metamerism - repetitive, absolutely identical parts of the body. In our case, these are rings. Nereid is a worm endowed with specially developed musculature. He can easily dig in the bottom of the soil to hide from danger, or lay eggs. Nereid is quite small, it rarely reaches four centimeters in length, mainly its height is two or three centimeters. But there are individuals in fresh waters up to 90 centimeters!

Such a "monster" can be found in the desalinated waters of Japan. It is called green Nereis. A nereid is usually a brown worm. It can sparkle with green, blue and red hues. The spectacle is truly a fascinating look. This worm is beautiful and absolutely safe for humans. Do not be afraid that he will bite you or decide to live in your body. Nereid lives in harmony with a person, and he has no interest in the quality of food for her.

Character and way of life of Nereis

Nereisy can live in the burrows on the seabed, but more often the worms simply burrowed in the mud. Often, while walking and searching for food, they float above the bottom surface. They can be called couch potatoes, since they do not move over long distances until the breeding season.

Recently, scientists have discovered a rather unusual, unusual for worms, feature of non-reis. They communicate with each other in the only language they understand. This happens with the help of chemicals that they release into the environment. They produce their skin glands, located on the body of polychaetes.

These substances are pheromones. They are different in purpose: some attract females, others scare off enemies, and others serve as a warning of danger to other worms. Their nereisy read using sensitive organs that are located on the head. If you remove them, it will lead to the death of the worm. He will not be able to find food for himself and will easily become the prey of the enemy. Several species of nereis behave like spiders on a hunt. They weave from special mucous threads of the network. With the help of which they catch sea crustaceans. Moving, the network lets the host know that she’s caught the prey.

The marine worm Nereis is considered an omnivorous invertebrate. He is able to eat algae, but meat food is preferable. Nereis eats:

  • shellfish,
  • small invertebrates,
  • organic residues

Worm nereis by nature endowed sharp and powerful teeth, but he is unable to cause any harm to the fish. The invertebrate picks up food debris after large predators that fall to the seabed. Often, sea worms in digging the underground bottom absorb sludge, which helps to strengthen the health of the invertebrate. It is precisely silt that contains organic compounds useful for Nereis.

Breeding nereisov

Nereis begin mass reproduction with increasing water temperature, while the mating period can be tied to the phases of the lunar cycle. Sea worms react to moonlight and float to the surface of the water. If the water is artificially illuminated using a spotlight, then this may cause a massive upwelling of marine worms. Scientists use this feature of the Nereis to lure rare species that are difficult to catch because they lead a bottom life.

The meaning of the conversion of nereisov in the breeding period is quite logical. When sea worms begin to swim, the chance of meeting the sexes and fertilization increases. Otherwise, inactive nereis would be difficult to find a mate for themselves. In addition, the active movement in the mating season contributes to the resettlement of the species. The reaction to moonlight and high temperature was developed in these worms just to carry out their mass swarming.

From the fertilized eggs the trochophores hatch. Their bodies are ringed with 4 ciliary rings. In appearance, trochophores are similar to insect larvae. They have not too long setae on the posterior margin of the head lobe, and from the sides of the body there are 3 lobes, with long tufts of segmented setae moving away from them, which resemble fingers of hands with long claws. Trochophores can independently obtain food, they grow very quickly.

Juveniles sink to the bottom, digs minks, and life goes on again. In certain species of sea worms, the larvae develop inside the egg, and young nereids immediately hatch from them. This progressive property contributes to a significant increase in the survival rate of the offspring, since a large number of predators attack the free-swimming trochophore.

Caspian nereisy, as already noted, are the main source of food for valuable sturgeon fish that need protection and to be listed in the Red Book.

How to store Nereis

It is unlikely that someone will argue with the fact that it is best to use fresh, just bought bait, but it happens that you have to buy a worm in advance and keep it for several days, or even weeks. But the storage of the Liman worm is different from the storage of other baits: it does not need to be kept alive. It will be necessary to drive out all the water from the worm, that is, to actually “kill”.

The following storage methods exist:

  • fortification: Fishermen also call this method "drunken sea worm." Bait need to fill with vodka or alcohol and put in the freezer. As a result, the Nereis becomes as if silicone and retains the volume,
  • salting: Worms are washed, sprinkled with salt abundantly and left in this state for 30-40 minutes. After they are laid on a flat surface, which should be tilted slightly, and left for 2 hours. After that, they are removed in the refrigerator, leaving access to fresh air,
  • Some anglers prefer to keep worms in their native sludge in a cool place at a temperature of about 10 degrees, but this method allows you to save the bait for 1-2 days.

The first two methods make it possible not only to preserve the Liman worm, but also to improve its structure: the bait looks more appetizing and does not fall apart so much on a hook.

It is important to remember that the worm does not tolerate high temperatures and in the heat dies in just a couple of hours.

The internal structure of the nereid worm

The muscles in the body of the marine nereid form a skin-muscular sac. This is a structure that does not have an internal cavity. Organs are separated by loose connective tissue, or parenchyma. From above the body is covered with skin, and under it are several layers of muscles. These muscles are not located in separate bundles, but tightly adhered to the skin. This is the skin-muscle bag.

The intestine of the nereida consists of three compartments: the middle is endodermal, and the extreme (anterior and posterior) - ectodermal.

Where do nereids live?

Not all the depths of the sea can meet such polychaete worm. They live in the coastal zones of the Caspian and Azov seas, as well as in the waters of India. Rarely found in desalinated waters, mainly in the zone of Japan.

Nereids do not live separately, they inhabit, creating dense settlements. Water for their life should be a comfortable warm temperature.

So we met with this representative and the inhabitant of the seabed. There is nothing terrible in Nereid, she herself is afraid of everyone!

About Nereis (sea worm, Liman worm)

Nereis (from the Latin. "Nereis") refers to the genus of polychaete worms in the nereid family. Its name comes from the Greek name of the daughters of the sea king Nerea. Like the sea maiden, the worm is quite beautiful: it has a bright green color and bristles of red or orange on the sides. His body shimmers, as if covered with gasoline film.

Some species of marine worm (nereis green) can reach 70 cm in length, but shorter species are usually used in fishing - up to 10-12 cm in length. They live in the sea, preferring burrows or muddy soil at a depth of at least 15-20 meters. The Japanese Nereis live in fresh water. They feed on everything that comes across: plants, algae, remains of fish, mollusks and crabs. Some species are able to weave like a web of secreted mucous filaments. When the threads move, the prey is caught.

Not so long ago, it was discovered that sea worms have their own language - each species has its own, understandable only to them. They communicate using pheromones, which are released into the water from the skin glands.

The worm is included in the diet of many marine animals, including crabs and commercial fish. In the late 40s of the twentieth century, it was specially transported from the Sea of ​​Azov to the Caspian Sea, where sturgeon were starving. As a result, the nereises perfectly adapted to the new conditions: today about a million tons of worms live in the Caspian Sea, and they have become the staple food for local sturgeons.

Nereis as bait for fishing

For the angler, the Liman worm will be indispensable when hunting any marine predator. They are high in calories, meaty and very attractive in appearance. Some species of fish, for example, the Caspian sturgeon, and at all feed only on them, also fastidious sea mullet is caught in Odessa. This is a universal bait, using which you can always count on the catch.

Using Nereis, you do not need to feed the fish, otherwise you can spoil it. If you really want, you need to use meat feed: crushed mussels, clams or finely ground fish. It is important to remember that the vegetative lure of predators is not impressive - they can even leave the place completely.

It is best to get Nereis in the same place where fishing is planned, but they can also be purchased along the way. Depending on the bite and the duration of fishing, they will require a different amount. Usually the bait is sold in boxes.

How to get Nereis

The search for Nereis can be a definite problem, since these are marine inhabitants, that is, they need to be looked for near the seas. To dig up Nereis, you must go to estuaries, preferably salty, or estuaries, which flow into the sea. It is worth paying attention to the sediments of silt and shallows - since non-forests prefer a muddy bottom, it is likely to find them there.

Choosing a place, you need to arm yourself with a durable shovel or shovel. Having scooped up the silt, it is laid out in a thin layer on the shore and waiting. During this time, you can fill the container for storing the bait with silt or dirt from the same place. The worm will give out itself, having begun to move, after that it is carefully collected, washed with a sieve and put in a jar.

However, many anglers, going to the sea, prefer to buy fresh worms from local residents. Also in the shops you can find silicone imitation of Nereis: it does not crumble and serves longer. But not all fishermen can agree with the latter option, since live sea worms are still preferable for fishing.

How to put Nereis on the hook

Since childhood, many anglers have dealt with earthworms and believe that there will be no problems with the Limansky worm. But they are mistaken: in contrast to the earth’s “brethren,” the Nereis are too soft and easily broken when pressed hard.

To hook it, use hook No. 7 and a special thin metal tube, hollow inside. First, the worm, like a stocking, is put on a tubule, then a hook is threaded into one end of the tubule and pulled out, dragging the worm onto the hook. This helps to keep the nozzle intact, in addition, the worm will look as natural as possible. I pull the worm on the hook from the head so that it does not slip off.

In order not to be mistaken, it is best to watch a video about this in advance:

For catching small fish, you can use pieces of a worm, for catching large ones, it is better to pull the bait in the manner indicated above or pierce with a hook in several places. You can also use worms for fishing, putting them "beam", puncturing them in several places for better retention.

The only significant drawback of Nereis is its softness: it easily falls to pieces even with little pressure or too sharp a throw. Handle them with extreme care.

Nereis is a popular bait for sea fishing. Predators peck on it well, but the handling of worms will require some caution, otherwise they will fall apart even before hooking.

Habitat Nereisov

Wrapped nereisy on the seabed, in burrows. They are eaten in large quantities by various commercial fish, Kamchatka crabs and other marine animals.

Nereisy very high in calories. They are the basis of the sturgeon diet, which is found in the Caspian Sea. For this purpose, they were even specially brought there.

Several tens of thousands of Nereis were delivered from the Sea of ​​Azov to the Caspian Sea in special refrigerators. And they are well adapted to the new conditions and multiplied in large quantities. Today the mass of these creatures in the Caspian Sea reaches millions of tons. As a result, Caspian sturgeon almost completely switched to food with non-reis.

Nereisy - feed for sturgeon.

These creatures are omnivores, that is, they can eat plants and predators, sometimes they eat rotting remains. Researchers have noticed how non-insects actively nibble decaying green algae, in which holes remain behind. These worms are collected in large numbers near the bodies of crustaceans and mollusks. That is, they are, in fact, hyenas of the seabed. Some species are able to secrete mucous filaments, which are used as a net for catching marine crayfish. When the network starts to move, the owner realizes that the prey is caught, that is, in this they are similar to the spiders.

The researchers found out one interesting fact, it became known that non-reises have their own “language”, which is understandable only for individuals of a particular species. These marine worms communicate with each other using a variety of chemicals secreted by skin glands and entering the water. These substances are called pheromones.

Nereisy - polychaete worms.

Some pheromones are used to attract individuals of the opposite sex, while others, on the contrary, have an unpleasant smell, they are used to scare off enemies. There are still pheromones that warn colleagues about the danger, as a result of which worms crawl away and hide in burrows. A small amount of pheromones in the water, these creatures instantly capture with the help of special sensitive organs. If this organ is lost in Nereis, it loses its ability to detect food and cannot hide from enemies. Observing the behavior of nereis, scientists managed to unravel the nature of many pheromones.

During the breeding season, the appearance of the nereises changes dramatically. The eyes become much larger, and the crystals are more pronounced. The blades expand and take the form of oars. Ordinary bristles are replaced by swimming ones, they are flatter and wider, and new tufts of bristles appear. Body segments expand, their number may even vary. Muscles become stronger. As a result of such transformations, nereises begin to swim and transfer to plankton feeding.

During breeding, these sea worms rise to the surface from the seabed and begin to look for a pair. As a rule, males are engaged in more active search. They move along the trail of pheromones that give off females. Some types of nereis do mating dances. Females swim near the surface, curving like snakes, while males circle around their chosen ones. At this moment, the worms are easy prey for fish and birds, which gather in the areas of mating of Nereis in large colonies and feed on these high-calorie worms.

Nereis multiply once in life.

The main feature of nereisov is that they can reproduce only 1 time in a lifetime. And after they fulfill their destiny, they perish. But one kind of nereis is an exception.Individuals of this species first develop as males, they find females mink, climb into it, fertilize its clutch, and then eat it. But the males do not abandon their offspring, and begin to take care of the clutch. Inside the mink, the males create an incubator, driving their parts of the body through the clutch with a stream of water and providing it with oxygen, which is very important for the developing embryos. Justice prevails and over time, the males turn into females, and when they lay eggs, the next generation males eat them just as well.

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