Tidal zone (estuaries). Rocky coast ecosystem of salt marshes
The article describes the aquarium fish of the African continent:
Rivers of Congo, Nile, Malawia - Nyasa and Tanganyika
(transfer)
The western and central parts of the African continent are occupied by moist equatorial forests. The climate of Equatorial Africa is constant. It repeats day after day: cloudless morning, cumulus clouds gather in the afternoon, which after noon showers with thunderstorms, and then the evening dawn of all shades, from yellow to crimson, adorned with dark cirrus clouds. There is more water with rain than it evaporates, therefore there are evergreen forests, many rivers, streams and streams, between which there are swamps, stakes, just water pits, puddles. Here, on the East African plateau, the mighty Nile River originates, from the numerous tributaries, the deep Congo draws strength.
In the oxygenated, but cool for warm climate and organic water poor rivers, the animal and plant worlds are mostly poor. This is due to the fact that there is a rocky bottom, an insufficient number of food organisms and a strong current. In order not to lose each other at least during breeding, the little Cneria male (looser) is forced to stick to the female with special suction cups that have formed on his gill covers. The inner surface of the suction cup is embossed and helps the fish hold on tight. If it weren’t for this, the turbulent stream would spread milk and caviar instantly, and caviar would remain unfertilized in different directions.
A little lower the current slows down, numerous tributaries increase the river. The waters of the marshy tributaries are brown in color. Water hardness does not exceed 1-2 degrees. The bottom is covered with a thick layer of silt and half-rotten leaves. Such rivers are called "black". The water in them is sometimes so acidic that fish and plants avoid it, and only after floods on the silt green sprouts appear for a short time.
There are also “white” rivers. They flow in areas with clay soil, wash particles out of it and become cloudy yellow, reddish or whitish-gray. Water hardness in them is from 0 to 3-4 degrees. Through pollution, such rivers are also sparsely populated.
In the middle course of the river there are many simple, copepods, insects, as well as fish, amphibians, waterfowl and animals. Vegetation on the marshy shores approaches the water itself, the bent branches of trees hanging over the water. Among the fish, good swimmers predominate. These are representatives of the haracin and cichl families. Many in the rivers and barbs. At the bottom live catfish. Under the flooded tree trunks, there are flocks of flat fish-knives standing head to the stream, African glass catfish swim in ghosts.
Congo lives on the sandy reaches tetraodon myurus. This fish-ball buries itself right into the ground. Yellow - brown skin with dark spots is invisible against the background of the bottom. The body is angular, slightly inflated.
Striped fish fahakidistributed in Africa over a large territory - from the source of the Nile to the Gulf of Guinea. They live in fresh and sea water. They form a large number of subspecies and local forms. Fahaki from Lake Rudolph are up to 6 cm long, while usually fish of this species are up to 40 cm long.
The bulk of plants are hornwort, vallisneria, water fern, elodea. On the surface ricchia, pistia and duckweed swim.
Continuous fields form along marshy shores and in river deltas nymphs. There are many of their species. They are also distributed everywhere in Eurasia, Africa and America. In our country, one of the types of nymphs is called white water lilies. Brought dozens of colored varieties of nymphs for breeding in decorative ponds. The flowers are yellow, pinkish, light red, blue or slightly purple in color. Variegated nymphaeum is common and popular in aquariums. Its thin, wavy at the edges of the underwater leaves change color from green to green-purple, depending on the lighting. Gently red or brownish-purple spots are scattered throughout the plate. The underside of the leaves is pinkish-purple. The leaves of the red nymphaea are red. The flowers of a tropical water lily open at midnight. Unlike our water lily, aquarium nymphaea lack a thick creeping rhizome, and tuber forms. Propagate by lateral shoots.
In the shady forests of Africa, in the ponds grow fern bushes painbitis. Openwork, as if carved, dark green leaves of this fern depart from the creeping rhizome. The roots do not climb into the soil, but over time they can gain a foothold on the surface of underwater objects. Plant growth up to 30 cm. In the aquarium, it multiplies by dividing the rhizome.
Often found in aquariums and anubias- small marsh plants with dense glossy leaves of ovoid and oval shape. The yellow inflorescence of Anubias is shrouded in a white stripe. Anubias grow along the edge of the water. Their leaves remain in the air, and the roots are immersed in soft soil. Anubias grow slowly under water.
Clouds of mosquitoes fly over the water, and their larvae live in the water, they are collected with a wide mouth of fish - butterflies. With fast strong vibrations of the elongated rays of the caudal fin, they accelerate, jump out of the water and, spreading huge pectoral fins, fly out two or three meters in pursuit of insects. The catch is also strayed by splashes of water generated during the jumping of fish.
Near the bottom between the stems of plants and swim neolebias- fish of the suborder characiform. They are 3.5 cm long. The back is olive-brown, on the male the sides are brownish-red, closer to the abdomen - yellowish. A dark strip runs along the body, bounded above by a golden line. On the basis of the caudal fin there is a dark speck. Anal fin red with a narrow dark border. Tail and rectangular high dorsal fin cream. Female Neolebias are less brightly colored. The small adipose fin behind the dorsal, characteristic of most characiform fish, is absent in Neolebias. Their mouth is small, placed on the end of the head, so they need to choose a small food in size. The temperature in the aquarium should be 20 ... 24 C. Propagate in the same way as South American characiform fish.
Elongated, variegated, predatory fago - also representatives of characiform fish. In the thickets of plants, they prey on tadpoles, fry. At night, many ctenopomas - African labyrinth fish - change the phage.
In addition to labyrinths, a number of perch-like species are widely represented in African reservoirs by cichlids or cichlids. They look like labyrinths, but their body is a little more massive.
Cichlidsavoid strong currents and swamps. Many species are found in brackish waters of coastal ponds and in estuaries.
By behavior, cichlid fish are territorial. Each male, and occasionally a female, occupies a certain area among the dense thickets near the bush or the gap between the stones; they get food at the bottom. Fish longer than 5-6 cm prey on fry. Largest african cichlids - tilapiadig up and eat water plants.
In an aquarium, cichlids are best kept in not very fresh, but not in old water. 1 / 5-1 / 4 of the water every two weeks is replaced by a defended tap. Pots, driftwood, stone minks are placed at the bottom of the aquarium. Plants are placed so that subsequently thickets form. In the clashes for hiding places, the leader is determined - the owner of the largest site. Fish are fed a variety of live food, herbal supplements. Fishes often readily dig in the ground. Therefore, only good filters can provide purity of water.
In the forest lakes of South Nigeria live cichlids are parrots. The body of these fish is elongated. The male is yellowish brown with a blue or purple hue. Along the body and the rhomboid caudal fin is a black stripe. On the side, near the anal fin, there is a purple spot. The long dorsal fin is dark gray with a silver or golden top edge, in some fish with spots. The lower part of the caudal fin is gray, the upper part is pink, sometimes with several spots. The ventral and anal fins are blue. The body length of males is up to 9 cm. The body of the female is taller, fuller. The abdomen is fuller, rounded, purple. The golden stripe on the dorsal fin is wider, with one or two dark spots in the back. Gill covers violet, shiny. Body length up to 7 cm. In all cichlids, depending on the condition of the fish, living conditions, time of day, the presence of a leader or a person of the opposite sex, the color changes. Frightened or resting parrots are discolored.
It is better to keep parrots in a flock in an aquarium with a volume of at least 40-60 liters. Water temperature should be 22 ... 24 C, hardness up to 10 degrees. For breeding parrots, the water is partially softened, and heated to 26 ... 28 degrees C. It is better to place a couple of fish in a separate aquarium with a flower pot. A hole is made in the bottom or side of the pot into which adult fish could swim. In natural conditions, before breeding, fish dig a mink under a stone or snag. Aquarium fish carefully inspect and clean the pot. Such a ritual is simply necessary for the couple. At this time, their readiness for spawning is finally formed, the last changes in the body are ending. A joint clearing of a hole in the potted sand will strengthen the relationship between the male and the female.
After spawning, 120 reddish eggs remain inside the pot. All cichlids worry about offspring. Parrots fan caviar with fins, peck eggs infected with bacteria. Three days later, larvae appear that hang on the walls of the pot. Five days later they become fry, swim, feed on grated food - ciliates, Artemia larvae, "live dust". Producers still inspect their fry for a long time. In the afternoon, small parrots swim near adult fish and eat small live food. If the family swims from place to place, then all the babies are held in a group behind an adult fish so that they can see it at a certain angle, that is, the larger the fish, the fries are kept farther from it. If necessary, adult fish grind food for fry, grind worms, larvae, insects. How long care should last, fry determine themselves, releasing odorous substances into the water. Feeling this smell, parrots parents rush at uninvited guests, do not swim away from the offspring.
Equal care for offspring is shown and distributed in Equatorial Africa. Chromis handsome. It is better to keep adult fish in pairs: in a common aquarium they start deadly fights with fish of their species and others. Beautiful chromies in natural conditions are 10 cm long, in aquariums - half as much. Fish 7 cm long can breed.
Despite the exorbitant aggressiveness, many lovers contain these fish due to their very beautiful color. Their body is purple-red. On fins, greenish-blue shining dots. On the gill cover, in the middle of the body and near the caudal fin, there is a black mark in the rim of blue glare. In females, the front of the body is more golden.
Adult cichlids communicate with fry using fins movements, various body postures. This is especially noticeable in bright chromises of handsome men. So the fry gather under the female in the trench dug at the bottom, when she quickly pulls the dorsal fin, then lowering it, then opening it. The blue glare of light disappears and flashes again. Malkov, who did not notice the female signal, is picked up by his father. Inspecting every nook and cranny of its territory, the fish searches for the kids and takes them into its spacious mouth. At the same time, in the fry, the swimming bladder reflexively contracts, they become heavier than water and lie motionless in the mouth. They also lie motionless in the nest.
And yet, no matter how cichlids are not worried about their offspring, they eat part of it after the end of the period of departure. It is simply necessary in nature to preserve the species. Hunting your own youth is the only way to survive in a closed pond, inherent not only for cichlids. After all, fry feed on microscopic animal and plant foods, which adult fish cannot eat.
Guelter's Pelmatochromisfound in water from Ghana to Cameroon. Males 20 cm long (in captivity - about 10). Females are smaller. The body of the fish is high, the head is large. The color of the male is grayish-brown. Three dark stripes stretch from the gill cover to the caudal fin. Gill covers with a blue metallic sheen. The pectoral fins are also blue, the other fins are gray. Dorsal fin with bright red border, tail fin with bright blue dashes. The coloration of the female is brighter. Brownish body, large bright red spot on the abdomen. Gill covers yellow with a blue tint. The pectoral fins are reddish-blue, the rest are gray, the tail is slightly blue. The upper third of the dorsal fin is golden, expressive black dots are scattered across the fin.
Gunter dumplings are aggressive towards other fish, especially during spawning. They can be kept with peace-loving large cichlids and barbs. Water should be the same as for all fish in equatorial Africa: softened, not very fresh.
Preparing for spawning, fish with their thick lips peel a flat stone and lay 150-200 yellowish-gray eggs on it. After fertilization, both male and female take eggs in their mouths. The skin on the lower jaw stretches to form a transparent bag. Through the skin, you can see how the fish constantly mixes eggs, providing access to them of oxygen, cleans microorganisms from their shell. If only one of the parents incubates the eggs, the other should be landed from the spawning grounds, because the fish is trying to take the eggs for itself. With the joint bearing of eggs during feeding, Gunter's pelmatochromis transmit eggs to each other. At a temperature of 26 ... 28C, fry appear from eggs after three days. Parents can no longer hold them in their mouths, and fry are spreading in search of food. Adult fish help them find larvae of insects and worms in the soil, chew them and spit them out to fry. After another 3-4 days, parents are recommended to be jailed. Youth begins to eat on their own.
Comparing the number of eggs in different species of fish, you can see that the less they care about their offspring, the more eggs they lay. Ctenopomas, for example, also belong to the labyrinth, but do not build nests. The eggs, which are supported by a large fat drop, float on the surface with the flow, scattered by the wind and waves. Caviar dies, falling into adverse conditions, it is eaten by birds, amphibians and insects. Fish spawn tens of thousands of eggs in a single spawning season. And this is far from the limit. Many species of marine fish that live in the open ocean lay tens of millions of eggs. Only a few fish survive to adulthood, the rest die for various reasons. In fish that care about their offspring, the number of eggs is much less.
When parents or one of them carries caviar in the mouth, then it practically does not die. All larvae come out of it. So, in Gunter pelmatochromis 150-200 eggs, and in chromis 80.
The branched river system forms, over time, numerical bays, elders, cut off parts of the channel from the river. Old water bodies begin to silt, overgrow and turn into swamps. Each reservoir has its own characteristic composition of living creatures, most adapted to life in it. So, in the rivers of Africa, especially its equatorial part, elephant fish live. They are well adapted to this. Elephant fish have a proboscis on the lower jaw. The mouth opens at the end of the proboscis. Proboscis they extract food from soft sludge, which sometimes settles in pits in a few - meter layer. Fish swim in complete darkness, so their eyes are small, they see poorly, they sense surrounding objects with the help of dowsing. Two hundred times per second, a special group of muscles on the tail of the fish produces a weak electrical impulse. An electric field is created around the fish. An object that appeared nearby bends the field lines of force, and the fish feel it.
Electric catfish It gives out powerful electrical impulses that jam small fish, frogs, and other small aquatic animals. So, catfish, moving relatively little, gets its own food.Among the catfish there are many interesting in structure and lifestyle. For example, catfish from the hairy family on the mustache have outgrowths and membranes. Like most catfish, they lead a nocturnal lifestyle, and relax during the day. Fishes of two species of this family sleep during the day at the surface of the water, belly up, so that it is more convenient to swallow air with the lower mouth. To prevent birds from noticing them on the surface, the belly of the catfish is black, and the back of the light is spotted. Also, having rolled over on their back, they swim and collect insects from the surface.
Thousands of flocks live in closed reservoirs, streams, swamps and pits with rainwater african carp-like fish: epiplates, aphiosemions, rolofey. The main food of the carp-like is insects flying over water, mosquito larvae and pupae, and small crustaceans. Small fish often themselves become the only prey of cichlids and catfish in enclosed bodies of water.
Fish of the great genus afiosemions most often fall into aquariums. Their body is cylindrical, slightly compressed laterally. Dorsal fin shifted back. Almost all colors of the spectrum are combined in the coloration of males. Often there is a geographical variation in the color of the species.
Afiosemion South the same size. Lives in the coastal swamps of Congo and Gabon. The color of the male is brownish - red, very dark, especially at night and during spawning. Behind the head, the scales are light blue with a green tint, shiny. Large red spots are scattered throughout the body. Along the elongated reddish-brown dorsal and anal fin, there is a cherry strip with greenish-blue on the dorsal and white rims on the anal fins. The caudal fin is lyre-shaped, bottom and top with white or pale orange stripes. The tips of the caudal, and sometimes the anal fins end with white pigtails. In some water bodies, fish have a blue tail pattern.
The females of the afiosemions are poorly colored, in brownish and olive colors. Reddish or brownish small dots are scattered throughout the body and rounded transparent fins.
Area two-lane afiosemioncovers a large area. He lives in stagnant bodies of water in forests and savannahs. Male up to 6 cm long. Body brownish-gray or reddish-brown. Numerous crescent-shaped spots merge into a red net. On the sides of the body, the scales have rows of small green dots with a metallic sheen. In fish from southwestern Nigeria, these points are bronze. Two parallel black stripes stretch along the body, one strip passes in the middle through the eye, the other a little lower. The bands are more distinct in fish from the western part of the range and almost disappear in fish from the eastern part of the range. The stripes may turn pale or blacken depending on the conditions: during spawning, males fight or from fright. The unpaired fins of the two-lane afiosemion are very long, especially the dorsal - orange with rows of black dots. The upper part of the dorsal fin is red-orange in fish from Nigeria or lemon-yellow in Cameroon. Black and blue lines run along the edge of the dorsal fin. Anal fin orange or light green at the base with a red stripe at the bottom. The shape of the caudal fin varies from rounded (Nigeria, Cameroon) to lyre-shaped with very long extreme rays. The upper part of the caudal fin is pale orange, the lower part is bright orange, the middle is covered with red spots or strokes. The pectoral fins are orange or yellow in fish from southwestern Nigeria and colorless in fish from the Niger Delta. Females of a two-lane afiosemion are brownish, with a white abdomen and two longitudinal stripes on the body.
The content of the afiosemions is simple. They feel good in a low aquarium with a large surface area, where there are many floating plants. From finely leafy plants for fish, it is necessary to create thickets where females and young males will hide. Coloring fish will benefit more with dim lighting and a dark background.
The water in the aquarium should be old, peaty and, if possible, soft. Poor African carp-like tolerate water purging. Water temperature should not be higher than 21 ... 23C. The warmer the water, the faster these fish develop, age and die. Too warm water in natural reservoirs tells them that the reservoir is gradually drying up and that offspring should be left sooner.
Afiosemions in natural conditions live in large flocks. The strongest male leads the pack. He first swims to food, has an advantage during spawning. If the substrate on which the fish lay eggs is small, then the leader considers himself the sole owner and fertilizes the eggs of all females. Other males at this time swim away and start fights among themselves. Establishing calm, the leader from time to time disperses the brawlers. If he is defeated by a young male, the old one hides in plants. For several days he will not eat, turn pale, and then stick to the pack as an ordinary member.
According to the method of spawning, afiosemions are divided into two groups: those that attach eggs to plants (southern and two-lane), and those that dig eggs in the soil (goulis, afiosemions filamentozum, Gardner, blue). Some species, the aphiosemion Alya, for example, spawn on plants during high water, and in the drying ponds into the soil. For fish of the first group, a spawning ground of 10-15 liters with old water from a common aquarium is needed, several small-leaved plants are thrown there. A pair is placed for spawning, or, if the male is very active, then two females and males. The male in this case is replaced every 10-12 days. Spawning lasts several weeks, sometimes fish lay several eggs daily throughout their lives. With age, the number of eggs in females increases.
The substrate with glued eggs is transferred to flat vessels, where a layer of water is 3-4 cm, the vessels are covered with glass. The eggs are yellowish or brownish, in some species with noticeable dark dots or a net. If the caviar dies, is affected by microorganisms, it is necessary to drip 2-3 drops of methylene blue per 1 liter of water into the spawning ground. At a temperature of 22 ... 24 C in 12-18 days, larvae appear from the eggs. If the larvae cannot tear the solid shell of the eggs, then fresh water should be added to the water, the vessel should be gently shaken or a pinch of dry food or several sugar crystals should be poured into the breeding ground. Bacteria will immediately appear in the water, which will tear the shell of the eggs. From the first hours of life, small afiosemions feed. Larvae begin to feed with ciliates and "live dust". Larvae grow quickly and reach a length of 3-4 cm in a month and a half, and after a month and a half they become sexually mature.
In the spawning ground for aphiosemions that lay eggs in the soil, the bottom is closed with a layer of digested peat 2-3 cm thick. Fish dig eggs with sharp blows of the tail. After spawning, water must be drained to the peat. The spawning grounds are kept closed in the dark at a temperature of 18. ..24 C. After 15-20 days, peat from the spawning grounds is carefully filtered through a sieve, laid out on a newspaper to remove excess moisture, and placed in plastic or flat glass jars. In this state, caviar can be stored for 4 to 9 months. At this time, the development of the embryo ceases. Under natural conditions, developmental delay - diapause occurs at a time when, at times, the body of water begins to dry out. After the pond dries, the caviar is stored in wet sludge. After rains or floods, soft water again fills all the troughs. The eggs come to life, development continues, but after a while it stops again. The embryo is already noticeable in the egg. Diapause occurs again due to lack of oxygen, which is absorbed in large quantities by rotting residues. The duration of the second period of calm is 6-8 months. The development of embryos continues only after the appropriate conditions in the reservoir resume, green plants appear. Then, with the first heavy rain from the eggs, larvae appear in 30-40 minutes. In captivity, the development of eggs of afiosemions is stimulated by the injection of soft water at a temperature of 18C to the level of 7-10 cm.
Nota Branhius Rakhova exported from the vicinity of the port of Beira (Mozambique). The glassy red body of 5-7 cm males is covered with blue spots on the scales. Dorsal fin blue-green, anal blue. The pattern consists of wide brown or black lines and stains. The tail fin has a complex pattern of black, green and orange stripes. A wide blue ribbon runs along the edge of the transparent pectoral fins. The female is smaller, gray-brown.
After spawning of notobranchiuses, 50-60 small eggs remain, protected by a strong shell. From July to November, their livestock will be trampled along the roads, people will walk along them, the earth will become solid as stone, and cracked by heat. But with the onset of rains in the water there will be a new generation of notobranchiuses.
Entangled in the thick fur of animals, glued to the paws of birds and amphibians, the caviar of the notobranchius spreads tens of kilometers from its pond. Sometimes birds carry them even in the hollows of trees, where there is rainwater.
Otherwise, African drought breathing protopters. Their thick body seems naked, because the scales are deeply hidden under a layer of mucus. Paired fins lost their rays and turned into some kind of elongated trickles. With the onset of the dry period, the fish dig into soft silt at the bottom, curl up and cover themselves with a cocoon of mucus. Protopters breathe atmospheric air through a small hole in the cocoon. A day or two passes by, and in place the rate remains only a cavity covered with viscous silt and thick herbs. Protopter hibernates. Locals at this time dig them with a shovel, looking for fish on small mounds with a conical hole at the top. In the protopter cocoon, you can transport and forward. Once in the water, the cocoon softens, and emaciated fish appears from it. On the body, wrinkles, pressure sores, imprints of their fins are noticeable. Gradually, the protopter begins to move. After a long sleep in the water through the gills, a number of metabolic products are released, because for many weeks and months the protopter lived, breathed, received energy from its own reserves of fat. Protopters gather locals for tasty meat.
Lakes Tanganyika and Nyasa are one of the deepest lakes in the world. The greatest depth of Tanganyika is 1435 m, and Nyashi is 706 m.
Unique living conditions have preserved for tens of millions of years the animal world, which is found only here and nowhere else. Such living organisms are called endemic. More than 242 species of fish live in Lake Nyasa, of which 222 are endemic, and in Tanganyika, 190 species are 173 endemic.
Lakes lie close to the equator. Therefore, on the surface, the water temperature ranges from 23 C to 28 degrees C. As in most lakes, there is no strong flow and mixing of warm water with cold. At the border of the waters, there is a border between life and hydrogen sulfide asphyxiation. Hydrogen sulfide bacteria are the only living creatures of the deepwater part of the great lakes. They exist due to dead organic matter. Oxygen is not needed for hydrogen sulfide bacteria.
The main sources of water that feed the lakes are rainfall (1/3 of the annual influx) and many large and small rivers that flow into them (2/3 of the annual influx). In total, for the year this amounts to 72 km3 for Nyasa and 65 km3 for Tanganyika. Less than 1/20 of this amount of water flows from Nyasa to the Shireya in the Zambezi and Lukukoy from Tanganyika to the Congo. The remaining water evaporates. Therefore, the salt content here is quite significant for fresh water - 0.5-0.8 g / l. The active reaction of water is slightly alkaline.
Life in the lakes is unevenly distributed. The most populated in these lakes is the coastline, which is very indented near Nyasa, in many places stone cliffs go up to the water, break off into the depths of 5-15 m. Throughout minks, caves and depressions, their owners peer out - bright cichlids. Africans call Lake Nyasa Malawi, so it is customary to call Nyasa fish Malawian.
Melanochromis auratus 11 cm long. The body is elongated, cylindrical. The adult male is brown-black with two pale blue stripes along the upper body. Almost all fins are black. The long dorsal and caudal fin margins are yellow, and the edges of the anal and ventral fins are blue, opaque. The female is smaller, golden yellow with two black longitudinal stripes. The third strip is on the dorsal fin. Anal and ventral fins are blue.
Pseudotrophyus zebra also 11 cm long, but his body is much taller. There are several color options for these fish, so it is difficult to determine the species. Of course, zebras are blue with dark transverse stripes. Sometimes there are no stripes, and the body color is very light, milky blue. There are fish completely white or with a reddish-pink hue. In females, sometimes on a blue or white background, the body is blackish, brown and orange spots.
Pindani12 cm long. Oblong body and fins of light blue color. Across the sides runs from a dozen narrow dark stripes. The front rays of the pectoral fins are milky white. In some places along the coast, the pindans have a black stripe on the dorsal fin. Such a black stripe runs along the lower edge of the anal fin, decorated with ten to twelve yellow releases. The female is very similar in color to the male, even there are releases, albeit pale ones.
Pseudotrophies Lombardo 10 cm long have a pronounced sexual dimorphism (the difference between male and female). The male is orange, sometimes with several transverse dark brown stripes. The female is blue with black and blue transverse stripes on the body.
In melanochromis Johann the females are yellow - orange, and the males are dark blue, almost black, with two shiny blue stripes along the body. As with all cichlids, the tips of the ventral, dorsal and anal fins of the male are longer and sharper than in females.
Their appearance has several dozen color options. We described a small part of the fish of two related genera - pseudotrophaeus and melanochromos. In the aquarium, these genera are represented by twenty species. Many of them are very similar in color. So, the male melanochromis of Johann can look after the orange male of the pseudotrophy of Lombardo, who reminds him of his female.
The indefinite species of Malawians are given a temporary designation. For example, the M7 pseudotrophyus means that it is the seventh Malawian (M) pseudotrophyus of indefinite form. From time to time, scientists conduct revisions of the genus and give the fish a scientific name. So, under the name M7 pseudotrophyus, petrotilapia or Mbuna kumva was introduced, which in the local language means "the one that attacks the rock." The name of the fish was for surrounded by thick lips, dotted with sharp teeth of the jaw, with which it removes algae from stones. Deprived of plant foods, petrotilapia ceases to multiply and grow, gets sick and dies. Petrotilapia are up to 20 cm long. The mouth is wide. Males are bluish-blue with orange-scarlet strokes on the fins. Females are smaller, brownish yellow, with dark transverse stripes on the body. Coloring of fish is inconspicuous and variable. There are also golden-colored specimens.
Long-bodied Labotrophaeusthe usual one is 12 cm long. It is distinguished by a large overhanging upper lip, for which it is sometimes called an ax fish. There are several options for coloring fish. Males and females are often blue with subtle transverse stripes. The dorsal fin is reddish-brown to orange. About half of the females are born with an orange-yellow body covered with red, black and blue spots. Very attractive color of orange females with a pink-red spot on each side scales.
Small (6-10 cm long) fish of the genus labidochromishave a blue color in all shades. The male blue labidochromis is whitish blue or light balt. A wide strip on the dorsal fin, spots in the front of the anal and ventral fins are black. All fins with milky white stripes are in front. Females are gray-blue. For liveliness of movements, brilliant color and small size of labidochromis, they are also called hummingbird cichlids.
At Freiberg's labidochromis male is light blue with wide transverse violet - blue stripes. Head and fins with a purple hue. The ventral fins are black with a milky white first ray; the anal fin has a black spot. The female is smaller in size, gray-blue, without a pronounced pattern.
Like most other fish, Malawians choose a certain interval of depths for their life, beyond which they try not to follow. With a decrease in illumination, algae disappear, so deep-sea fish feed mainly on mollusks and other invertebrates. Colors are lost at dusk, first red, then orange, yellow, green. The last to disappear blue and blue colors. That is how the deep-colored haplochromis is painted - blue with a metallic sheen.
A large role in the life of water bodies is played by sandy beaches. Wave after wave rolls onto clean, wet sand. Water seeps between the grains of sand. Along the surf, organic and mineral water-insoluble substances are retained by a layer of sand and decompose by billions of invisible bacteria, amoebas, and ciliates. Beaches are natural filters of lakes. In addition, rich food reserves are collected on the sandy shores, especially where a river flows into the lake. Rivers bring a lot of dead organic matter that settles in a layer at the bottom. About a quarter of the bottom of the river is occupied by thickets of Wallysneria, hornwort, Elodea, and sometimes nymphs. Reed and papyrus come into the water from the coast. In sandy biotopes per 1 m 2 there are a hundred larvae of mosquitoes and crustaceans, a thousand shell crustaceans (in the thickets of plants) and up to 10 thousand small mollusks (in clean sand). Willingly visit the shallow flocks of herons, flamingos, who filter the water in search of food. Bird feces become food for micro-organisms, support the rapid growth of green algae, especially in the dry season, when small cave islands and streamers cut shallow waters into separate bodies of water.
There are 16 species of cichlids. Fish in shallow water, where there are no shelters, live in large schools and have a mild, inconspicuous color. Of these, aquarists are only interested in haplochromises of Livingston, dolphins and Queen Nyasa, who live on the verge between sandy and rocky biotopes.
Males haplochromis livingstone blue - blue. The body and head are large, the lips are thick. The lower body is brownish, the sides of the head with a blue-green shine. On the anal, dorsal and ventral fins there is a white border. Female light, with brown spots on the body and fins. Fish are 20 cm long.
The so-called dolphin fish belong to the genus haplochromis. The name of the fish was given to the male’s steep forehead, the fat pad of which increases with each spawning. Males are blue with a greenish tinge on their sides. Four to seven dark blue stripes run across the body. Females are lighter, with two very pale black spots on the side and reddish dots on the caudal stem. Body length 12-15 cm. Haplochromis in search of food constantly digging in the ground.
In flocks, along with other mainly blue inhabitants of the sandy and rocky bottom, the Queen Nyasa fish is found. In its coloration, the associations are destroyed by blue and reddish colors. Males 13 cm long, blue, with a metallic luster, ventral fins and tails behind gill covers orange-yellow or reddish. There are 8-10 transverse dark stripes on the body. The sides, and especially the back and head, are covered with blue dots. The dorsal and anal fins are blue with a white rim, the caudal fin is reddish with blue veins. Females are brownish-bronze; transverse stripes darker.
Adult fish occupy a permanent mink-cache and aft area and do not allow anyone into their possessions. Bright coloring signals the strength and intentions of the owner. The Malawian cichlids of rocky biotopes never move away from their place of birth, form family groups. The constant crossings between individuals close in blood and sedentary behavior cause the appearance and consolidation of new signs. So, if on Likoma island the males of melanochromis Johann have two blue stripes on a black background, then for the fish living on the Makanjili coast, these stripes turned into rows of blue spots.
Many inhabitants of rocky shores form interspecific flocks and settlement colonies. This is especially true for pseudotrefeuses and melanochromises that are similar in body shape, size and color. Interspecies flocks are another confirmation that these types of formations appeared here, in Nyasa, from a common ancestor and relatively recently, because the fish did not lose common characteristics.
Therefore, it is better to keep the Malawians in captivity in a common aquarium. In order to reduce the number of fights between males within their areas, one should avoid keeping fish of the same color, especially if they differ in size. It is better to pick one male of each species for three to four females. Interestingly, the aggressive attitude of males to females decreases in the general aquarium. During the pursuit, the female escapes to the neighboring site, the owner of which does not pay attention to her, but the male should never be allowed to enter his territory.
The general aquarium should be spacious - no less than 80-100 liters. When paired, smaller aquariums can be used. The total number of fish for the aquarium is determined by the rule: 2-3 cm of water should fall on 1 cm of the body length of the fish.
From limestones - sandstones, turtles, quartzites in the aquarium make multi-storey caves. The stones must hold tight so that the fish cannot drop them. You can peck them with silicone.
Often, to lighten the load on the bottom, they put flower pots, caves are made of pieces of opaque plastic or scraps of plastic pipes glued together. The aquarist must determine for himself what is important for him - the attractive appearance or practicality of the aquarium. When creating artificial shelters, it must be remembered that they should be without sharp edges and always with two exits. The plastic in the aquarium should not release any substances into the water. The best soil is coarse gravel. Crushed stone, which has sharp edges, can damage the lips and abdomen of fish. It is better to take gravel dark: fish on its background look brighter. Lighting, as in the lake, should be strong. Lamps are installed at the rate of 1 W per 1 liter of water. They place the lamps evenly, because the Malawians are afraid of their shadows at the bottom. From bright light, filamentous algae quickly appear on the surface of the stones, fish willingly clean them.
Malawian cichlids are very demanding on the purity of water and its saturation with oxygen. Water hardness is about 18 degrees; pH 7.5-8. To accelerate the biological purification of water, plants are planted in the aquarium: wallisneria, lemongrass, hygrophilus, echinodorus. They are placed in pots, and the roots are covered with stones, protecting them from being torn out by fish. Against the background of stones, the bright green leaves of the Thai fern look very beautiful. Small-leaved soft plants often eat cichlids, but it is these plants that quickly purify water. Therefore, elodea, najas, duckweed, etc. it can be placed either in the part of the spacious external filter, which is free from the filter element, or in a chamber 5 cm wide fenced off with glass from one of the walls of the aquarium. It is advisable to place an air atomizer here and connect the chamber to most of the aquarium with openings from above and from below. It will be a real biofilter. Every week, 1/4 of the volume of water in the aquarium must be replaced with fresh, settled tap water, the filters are regularly washed.
Malawi cichlids should be varied and nutritious. From time to time, fish are given a small amount of lean beef, heart, or liver. Fish develop well if they regularly feed sea fish fillets, shellfish, and shrimp.
With proper feeding and clean water in the aquarium, fish grow quickly and become mature at 9-12 months old.
Before spawning, males come to life, start skirmishes in the upper layers of water. Paired spawning takes place in a common aquarium. On a clean, stone-free bottom section, the female lays several large yellowish-orange eggs and immediately hides them in her mouth.
The caviar is fertilized with the milk of the male, on the anal fin of which orange release is noticeable. Female females do not have or are weakly expressed. Spawning lasts about an hour. During this time, the female lays 30-80, sometimes a little more or less eggs.
The development of eggs and larvae of Malawian cichlids takes place in the female's mouth in about three weeks. So that the female is not disturbed by other residents, she must be put into an aquarium with a capacity of 40-60 liters. with caves and the same water as in the general aquarium. Lighting should be calm, not very bright. The water temperature is 1 ... 2 C higher than in a general aquarium. Too warm water (29 ... З0С) is unsuitable, because it speeds up the metabolism in the body of the female and she is exhausted, becomes nervous, is scared of the slightest sounds and movements. There should be enough oxygen in the water. A decrease in the amount of oxygen in the water can cause the female to eat caviar, and weaken and injure the fry. It is better to carry the female in a plastic bag with water so that she does not get into the air. If the female remains in the general aquarium, it should not be affected by other fish. Feed the other inhabitants so that it does not bother her. Some fish, such as pseudotrophus, even with caviar in their mouth, eat a little every day. Since caviar develops in favorable conditions, almost all of its number leaves larvae, which is never the case with fish that do not care about offspring. But sometimes it happens that a fish eats its eggs. This happens when the female behaves very aggressively or when she is chased by a pugnacious male in a common aquarium. A hungry female should not see food, take foreign objects in her mouth.
With the extinction of maternal instincts, it is necessary to incubate artificially independently. The eggs are taken from the female only after the resting stage has passed, otherwise the development of the embryos will cease. At a temperature of 26 degrees C, this happens on the third day. For an incubator, a vessel with a capacity of 300-150 ml with a smooth inner surface is taken, washed with hot salt water and rinsed. Filling half with water from the aquarium, let the female. The body of the female, without taking it out of the water, is wrapped in a soft, clean cloth. Carefully opening the female’s mouth with a spoon, turn her head down and immerse it several times in the water of the incubator. Then the female is lowered into the net so that she calms down, and removed. Until the female calms down, one should not rush to transplant her into a common aquarium.
Fertilized caviar of the Malawian cichlids is oblong, opaque, evenly colored in light brown. At the sharp end there is a barely noticeable transparent drop of liquid. In the water of the incubator add 3 drops of a 1% solution of methylene blue per liter of water for disinfection. In the incubator, the caviar should lie on a plastic or glass mesh over which a spray is placed and a very weak flow is supplied. Once a day, water is completely replaced with water from the layer. Every 5-8 hours, the eggs are inspected and the eggs are removed with a pipette with a melted end and the eggs are affected by bacteria or fungi. The dead caviar has spots, dents, an unusual color. After catching dead eggs, water is replaced. Neglect of these rules can lead to the death of all caviar. Larvae are born large and pinkish. They are similar in color to females. The first two to three weeks, the fry eat cyclops, artemia, and small daphnia. If the female was carrying eggs, then she will look after the offspring for several more weeks, but it is better to plant it after the fry begin to eat on their own. For the correct development of artificially incubated fry, it is necessary to avoid a sharp pressure drop between the incubator (water level should be 5-8 cm) and the aquarium (water level З0-40 cm). The water level in the growth aquarium for two weeks should be low (10-20 cm). If you violate this rule, the swim bladder of the fry does not develop normally, the fry swim upside down, stagger. Under the influence of different composition of water and other adverse conditions, a 1: 1 proportion violation in the number of males and females is often observed, uncharacteristic colors appear. With proper feeding, regular replacement of part of the water, a sufficient volume of the aquarium, fry grow quickly and can be 4-5 cm long in four months. At this time, they must be fed with plant foods. Then the color of the fish changes. For example, the blue striped pseudotrophaeus of Lombardo turns into an orange male. Most Malawians gradually degenerate when closely related. Therefore, males must be replaced frequently. Quite often interspecific hybrids with an unusual color arise.
Tanganyika landscapes are similar to Malawian. The same cliffs, sandy beaches, placers of stones. Water is a little softer - 11 degrees of hardness. The waters of Tanganyika are populated by two types of herring, five types of glass perches, 11 species of trunks, coy catfish, barbs and haracin. The remaining inhabitants are cichlids. Similar conditions in the two East African lakes led to the formation of a group of fish with similar body structure, behavior and lifestyle. Many brightly colored fish species have been discovered recently in connection with the intensive study of the ichthyofauna of lakes and the export of fish. From 1963 to 1978 the number of known species of cichlids increased from 126 to 160.
In aquariums, the most common fish are rocky and rocky biotopes - yulidochromis and lamprologus. In a medium-sized aquarium, it is better to contain yulidochromis, similar to fry of auratus. The masked, pearly yulidochromisph and yulidochromis ornatus (gold parrot) live at a depth of 4-5 m, hiding among piles of stones. Their color is similar: three black longitudinal stripes on a yellow body. In mask yulidochromis, bands in some places are connected. To correctly determine the type, it is necessary to pay attention to the drawing on the caudal fin. In a golden parrot, the lower strip forms a black spot on the tail. Egg-yellow fin bordered by a light and then a dark stripe. Masked yulidochromis also has black spots at the base of the fin, but there are two dark stripes that are around the perimeter. There is a dark spot at the back of the anal fin. The pearl ylidochromis has a dark rim of the caudal fin which is very slurred, but on the caudal and dorsal fins there are blue luminous dots. The anterior part of the ventral fins, the upper edge of the dorsal, the upper part of the eye are also blue. The length of the fish is 6-8 cm.
Numerous minks in the rocks at a depth of 20-25 m will be occupied by the net and ordinary yulidochromis. An ordinary yulidochromis (yulidochromis Regen) has a body 12 cm long. Four black-brown stripes pass along it. The caudal fin crosses four to five transverse sinuous black stripes.
The conditions for keeping Tangan fish are the same as those in Malawi. Only water is replaced with small portions (1/20 part twice a week). Replacing a large volume of water with fresh can cause an aggressive attitude of adult males even to fry. Juvenile Yulidochromis fry live in flocks. They play among themselves, eat together, swim. Fishes of their species are peaceful. The fight ends with one of the fish turning upside down with its tail at the surface, and they cease to pester it. By eight to ten months, the fish become sexually mature, one after another from the pack pairs are allocated. It is impossible to distinguish a female from a male by color, males are only slightly smaller and thinner. A couple must stand out from the pack itself. Forced pairing in most cases ends in the death of the female. Pairs are formed constant. The opposite can be called Malawian cichlids, whose males form entire harems.
Fishes are spawned by the addition of fresh water. While laying eggs, the female swims in front of the male, turning sideways to him, and the male, with his head hitting the female’s back, begins to beat out the eggs from her. Then the female quickly turns upside down and glues eggs on the ceiling of a cave or ceramic flower pot. A few eggs, 50-60, in ordinary yulidochromissometimes 300. Spawning takes place at night or early in the morning. Parental care is shown by the male and female. The male, guarding the laid eggs, pounces on everything living, nervously reacts to loud sounds, movement near the aquarium. At a temperature of 25 ... 26 degrees, the larvae appear on 11-12 days. After 5-7 days, the yolk sac dissolves, and they begin to eat cyclops, artemia, rotifers, and then small daphnia, coreret, bloodworms. Adult fish are ready for spawning again after three to four weeks. Yulidochromis live in the aquarium for 10 - 12 years, retain the ability to reproduce up to 4 - 5 years.
Kind lamprologusrepresented by forty species in Tanganyika and four in Congo. Sizes of fish from 3.5 to 30 cm. Fish live from coastal shallows to a hundred meters
depths, some of them eat insect and mollusk larvae, others - vegetarians. Some eat small fish.
In aquariums, the most common are orange lamprologus and fragile fish - the Princess of Burundi. Orange lamprologuses reach 12 cm in length, their body is elongated, slightly compressed laterally, fins lemon or orange. Sometimes gray-brown specimens are found. The only spot of a different color on the body is a blackish eye. Males are larger from females, brighter colored. The behavior of fish is the same as in yulidochromis. Orange lamprologuses also form constant pairs. It should be remembered that the male’s extremely aggressive attitude towards the female and other fish of its species occurs in fresh water. The orange lamprologus opens its mouth so that in a few attacks with its teeth it kills the opponent. Fights can be prevented by keeping fish in old water and the presence of various species of fish in the general aquarium.
Double spawning in caves. Females of orange lamprologus lay 150 eggs each, which at a temperature of 26 degrees develop in two days. After 7-8 days, the fry begin to independently feed on rotifers and cyclops larvae.
It consists of living organisms, the environment in which they live, inanimate structures and how they all interact and influence each other. Marine ecosystems are found in salt water or in the immediate vicinity of it, which means that they can be found from a sandy beach to the deepest parts of the world's oceans. An example of a marine ecosystem is a coral reef with its inhabitants (fish, sea turtles, algae, etc.), as well as water, rocks and sand in the area.
Ecosystems can vary in size, but all of their components depend on each other - so if one part of the ecosystem is removed, it affects everyone else.
The ocean covers 71% of the planet, so marine ecosystems make up most of the Earth. This article provides an overview of the main types of marine ecosystems with examples of habitats and marine organisms that are found in each of them.
Rocky shore ecosystem
Cliffs, small and large boulders, rocks, and tidal pools that can support incredible diversity can be found along the rocky shore. There are also tidal zones - coastal areas flooded by sea water during the tidal season.
Rocky shores are extreme habitats for marine life. They are characterized by powerful waves, strong winds, as well as constant tides, which can affect the availability of water, temperature and salinity. During low tide, the threat of predation to marine animals increases significantly.
Rocky Shore Marine Life
The specific types of marine life depend on the geographical location, but in general, some types of flora and fauna found on a rocky shore include:
- Seaweed;
- Lichens
- Birds
- Invertebrates such as crabs, lobsters, starfish, hedgehogs, mussels, snails, saucers, ascidians and sea anemones;
- Seals and sea lions.
Sandy Beach Ecosystem
Sandy beaches may seem lifeless compared to other ecosystems of the seas and oceans - at least for marine life. Most sandy beaches are exposed to humans! However, they have an amazing variety.
The animal ecosystems of the sandy beach, as well as on the rocky shore, must adapt to an ever-changing environment. They need to deal with tides, wave impact, water currents that are able to sweep animals from the beach and move sand with stones.
The marine life of a sandy beach can be buried in the sand or quickly move away from the waves. Within this ecosystem, tidal zones are not uncommon. Although the landscape is not as dramatic as on a rocky shore, you can still find tidal pools left after the ocean recedes at low tide.
Sea life of sandy beaches
Sometimes on sandy beaches you can meet sea turtles, which are selected from the water to lay eggs, as well as pinnipeds such as seals and sea lions resting on the beach.
Typical marine life types include:
- Seaweed;
- Plankton;
- such as amphipods, isopods, flat shield-shaped hedgehogs, crabs, mollusks, worms, snails, flies and plankton;
- Fish in shallow water along the line of the beach. These include skates, sharks, flounders, etc .;
- Birds such as plovers, gerbil, membranous snail, godworms, herons, terns, stone-fronds and curlews.
Mangrove Ecosystem
Areas consisting of salt tolerant plant species. They are usually located in warmer areas between 32 ° degrees north latitude and 38 ° degrees south latitude. Mangrove trees have roots hanging in the water, providing shelter for various inhabitants, and important shelters for young marine animals.
Marine life of mangroves
Species that can be found in mangrove ecosystems include:
- Seaweed;
- Birds
- Invertebrates such as crabs, shrimp, oysters, snails and insects;
- Dolphins;
- Manatees;
- Reptiles such as sea and land turtles, alligators, crocodiles, caimans, snakes and lizards.
Ecosystem of salt marshes
Salt marshes provide a buffer between the ocean and the mainland. These areas are flooded at low tide and contain salt tolerant animals and plants.
Salt marshes are important in many ways: they provide a habitat for marine life, migratory birds, are important nursery zones for fish with various invertebrates, and also protect the rest of the coast by buffering wave action and water absorption during tides and storms.
Marine life of salt marshes
Examples of flora and fauna of salt marshes include:
- Seaweed;
- Plankton;
- Birds
- Sometimes marine mammals such as dolphins and seals.
Coral reef ecosystem
Healthy ecosystems of coral reefs are filled with an amazing variety of life: from hard and soft corals to invertebrates of various sizes, and such large animals as sharks and dolphins.
The main part of the reef is the coral skeleton, which consists of limestone (calcium carbonate). It supports tiny organisms called polyps. When the polyps die, they leave the skeleton behind.
Marine life of coral reef
- Invertebrates: hundreds of species of coral, sponges, crabs, shrimps, lobsters, anemones, worms, bryozoans, starfish, hedgehogs, nudibranchs, octopuses, squids and snails;
- : A wide variety of fish, as well as sea turtles and marine mammals such as seals and dolphins.
Algae forest
Algae forest is a fairly productive ecological system. The dominant life form in this underwater forest, you guessed it, is algae. They are found in cooler waters, the temperature of which varies from 5 to 22 ° C, at depths of 2 to 30 meters. This ecosystem provides food and shelter to a number of organisms.
Sea life in a seaweed forest
- Seaweed;
- Birds (gulls, terns, waders, cormorants, etc.);
- Invertebrates such as crabs, starfish, worms, anemones, snails and jellyfish;
- Fish, including sardines, garibaldi, perch, sea bass, barracuda, halibut, mackerel and sharks (for example, horn shark and leopard shark);
- Mammals such as sea otters, sea lions, seals and whales.
Polar marine ecosystem
Polar ecosystems are extremely cold ocean waters at the poles of the Earth. These areas are characterized by both low temperatures and temperature fluctuations depending on the amount of sunlight.
Marine life in polar ecosystems
- Seaweed;
- Plankton;
- Invertebrates: One of the most important invertebrate animals in polar waters is krill;
- Birds, for example, penguins known for their cold resistance, but they are found only in the Southern Hemisphere;
- Mammals such as polar bears, various species of whales, as well as seals, sea lions and walruses.
Deep sea ecosystem
The term "deep sea" refers to parts of the ocean whose depth is more than 1000 meters. But compared to some areas of the ocean, this is shallow, as the deepest areas reach about 11,000 meters in depth.
Lack of light is one of the main problems for the marine life of this ecosystem, but many animals have adapted so that they can see in low light conditions, or do not need vision at all. Another problem is pressure. Many deep-sea creatures have soft bodies, so they can easily tolerate high water pressures.
Deep sea life
The depths of the ocean are difficult to study, so we still learn about the types of marine life that lives there. Here are some examples of the inhabitants of the deep sea:
- Invertebrates such as crabs, worms, jellyfish, squid and octopus;
- Corals
- Fish such as anglerfish and some species of sharks;
- Mammals: sperm whales and marine elephants.
Hydrothermal vents
Although hydrothermal vents are typically found in the deepest parts of the ocean, they serve as their own ecosystem.
These holes are underwater geysers that spew mineral-rich, very hot water into the ocean. Hydrothermal vents are located along tectonic plates, where there are cracks in the earth's crust. The sea water in the cracks is heated by terrestrial magma. Under pressure, water erupts and cools, and minerals are deposited around the vents.
It doesn't seem like a very cozy place to live, does it? Despite the darkness, heat, water pressure, and chemicals that are toxic to most other marine creatures, some organisms thrive in hydrothermal ecosystems.
Marine life of hydrothermal vents
- - microorganisms that carry out chemosynthesis, which means the conversion of chemicals around hydrothermal vents into energy. They are the basis of the hydrothermal ecosystem;
- Invertebrates such as rifties, sea saucers, shellfish, mussels, crabs, shrimps, lobsters and octopuses;
- Fish such as beluga fish;
- Colorful coral reef near Similan islands, Thailand.
Such shores are the best place for photographing the inhabitants of littoral, because they differ in the richest variety of living forms, and, in addition, in this case there are no problems characteristic of photography on silty and sandy shores. The best time to visit the rocky shores is spring, since then the low coast is open at low tide and the photographer is given a rare opportunity to see and photograph the usually hidden life of the sea.
The most interesting thing for the photographer on the rocky shores is in the bays. On the rocky shores of these natural aquariums, you can usually find a rich set of living forms. Masses of brown algae, such as vesicular fucus (Fucus vesiculosus) and dentate fucus (Fucus serratus), can cover large boulders that open at low tide. These large algae are best taken under natural light, as a flash usually causes unwanted intense light flare. Seaweed, which becomes available for photography at low tide, is best photographed on a bright sunny day with an almost cloudless sky. You can use a tripod to get maximum depth of field at slow shutter speeds and small apertures. The presence of algae often indicates a change in plant associations offshore. Using a wide-angle lens, one can demonstrate how some species replace others as they approach the shore. It would be nice, showing a continuous cover of plants on the rocks, to give a close-up of their interesting details, for example, air bubbles on certain fuchsian ones.
On most rocky shores, you can find a huge number of sea ducks, "encrusting" the rocks, as well as mollusks, such as saucer (Patella spp) and litorina (Littorina spp). They can be photographed in a group, as well as alone close-up. For photographing organisms having a shell, natural lighting is best suited, as it emphasizes the furrow and overall relief of the shell. To be able to take advantage of sunlight, you must select objects that are in open places. If necessary, you can mount a tripod. Since some mollusks prefer shady spots, a flash may be needed. The shaded sides of boulders or rock ledges often provide shelter for fouling animals such as sponges.
Rocky shores are also rich in certain types of crabs. In temperate regions, they are quite small, rarely found and you need to look for them in crevices of rocks or under boulders and large algae. In the tropics, the situation is completely different. In Kenya, as night falls, coral rocks are covered with many striped crabs; in the growing darkness, the rustling of the legs of the crabs moving through the rocks is clearly audible.
During the day, thousands of these crabs can be seen under the ledges of the cliffs. The author received several photographs using a zoom lens and flash, and even a number of close-ups at a distance of several centimeters, photographing with a 55-mm lens.
Black Sea, rocky shore: right from the edge of the water, dense thickets of cystozira brown seaweed begin. The branches of its huge bushes, up to one and a half meters high, stretch to the surface with special bags filled with air. Bearded cystosiraCystoseira barbata - the main macrophyte alga of the coast in the Black Sea, a landscape-forming species. Epiphytic algae grow on its branches, fouling animals settle - sponges, hydroids, bryozoans, mollusks, polychaetes sedentary worms; small snails and crustaceans feed on the dying cells of its bark, fish nests hide and twist among its branches, and a marble crab and a crab mask under its colorinvisibility Macropodia longirostrisand numerous coastal fish of the Black Sea, and the snail of tricolium - all who live in this underwater jungle, stretching along the rocky bottom of the Black Sea from the surface of the water near the shore to a depth of 10-15 meters.
Greenfinch above the cystozira forest
The greenfinch male, having fertilized the clutch, protects it - drives away other fish from the entrance, ventilates the nest with a wave of pectoral fins. Such paternal care for offspring is a feature of most local fish -goby fish, whose masonry can be found under stones and large empty shells, behave the same way.
Greenfinchs eat, gnawing from the branches of algae and the surface of the stones the crusts of fouling animals - mollusks, worms, sea acorns. To do this, their fangs are pushed forward, and the mouth turns into solid forceps-tweezers to clean the underwater rocks - with their help they pull out the crabs and shrimps hidden in the cracks, crumble the shells of the mollusks and the tubes of the worms. Greenfinch live to the lowest boundary of rocky soil - 25-40m.
Graceful prawns of shrimp live in the crowns of cystozira Palaemon eleganssmall snails creep along the branches - tricolias, bittiums - and many other animal species that feed on dying bark cells and periphyton on the branches of the host alga. There are also small predators here - for example, the polychaete worm Nefis Nephthys hombergii. The crown of each large algae is a whole world, a community of animals adapted to live together, epiphytic macroalgae and the mass of microscopic organisms: these are bacteria, unicellular algae of periphyton (mainly diatoms), amoeba and ciliates; small crustaceans - sea \u200b\u200bgoats and other amphipods; isopods crayfish - sea cockroaches idotheas Idothea sp., harpacticides, balyanus larvae and others.
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Sometimes on the cystozira bushes you can find amazing fish - seahorses. Their caudal fin is turned into a tenacious tail, which they wrap around the leaves of sea grass or branches of algae, and they are quickly moved by a fluttering dorsal fin, so the skates swim very slowly and stand upright in the water. Black Sea Seahorses they look after the females beautifully - this happens in still cool spring water - two males, fluttering with dorsal fins, slowly swim around the female, weaving and unwinding their tails, snuggling up on their cheeks, pushing and flying apart, again drawing closer and colliding ... A bewitching mating dance of seahorses can lasts a week. Males demonstrate to the female overgrown brood bags, and she chooses who is better. In the bag of one of the contenders, she will eventually lay eggs - and the male, having fertilized, will carry it until the tiny skates hatch. The same thing happens with relatives of seahorses - sea needles: both of them and others - males become pregnant! |
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Tireless divers who can observe carefully can be rewarded with a meeting with an unusually beautiful fish - probably the brightest in the Black Sea - a red troper. The tropera females are colored the color of algae, but the males guarding their territory on the sides of large underwater boulders are red like arterial blood! These fish prefer to live on vertical rocky walls overgrown with algae, on which they cross on their “paws” (each of the “three feathers” - separated by rays of pectoral fins). |
male guarding |
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Here you can meet large stone crabs. Erifia verrucosa- True, there are not many of them on the very shore - souvenir manufacturers and vacationers are catching. Each stone crab has a favorite shelter and its own territory around, which it protects from neighbors. Although, like the other crabs, the stone, by the way of feeding, is also predominantly scavenger, it is so strong and agile that from time to time it manages to grab careless fish, or crumble the shell of a living mollusk - even an almost invulnerable rapeRaapana venosa (up to 5 cm in size). His carapace is strong, covered in spikes and sharp hairs. The eyes, like the whole body of the crab, are covered with cuticles - and even sharp hairs stick out from his eyes. At any depth here - lie masked among algae, variously colored scorpion; meandering, swim from stone to stone the ubiquitous ordinary sea dogs. |
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Flocks of mullet swiftly sweep at a shallow depth, above the very crowns of algae - these are large fish with silver scales. During seasonal migrations along the shores of the Caucasus and Crimea (in spring - for feeding in estuaries, Azov, river mouths, in autumn - for wintering under the Caucasian, Crimean, Anatolian shores) they move in huge masses - hundreds of fish in one school. That is why in April-May and in October we most often see dolphins off the coast - they pursue shoals of mullet. In the Black Sea, several species of mullet live, but on the coast we are most often found mullet single Lisa aurata - not the largest - up to 30cm, the appearance of these fish, which is easy to identify by the orange spot on the "cheek" - the gill cover. Mullet is a great swimmer, but she finds food at the bottom - she simply eats silt and even sand, raking the ground with her lower jaw, like a shovel. What is edible will be digested and assimilated, and everything else will pass through the fish, and again will be at the bottom. Fish that eat this way are called soil eaters, or detritophages. Since an unlimited amount of detritus is formed in the Black Sea, the food supply of mullet is inexhaustible. All types of mullet are able to live in sea and fresh water (euryhaline fish), which gives them a huge advantage - juvenile mullet is kept in river mouths and in shallow water right on the shore, where they are not threatened by marine predatory fish - bluefin, horse mackerel, larkfish; they walk in estuaries and estuaries rich in nutrient silt, where the differences in salinity are very large; mullet winters at a depth of more than 50 m under the steep shores of the Black Sea - in the most stable conditions. |
 Mullet singil Lisa aurata Other types of mullet in the Black Sea: which became small pointy Mugil saliens; larger mullet loban Mugil cephalus, widely distributed along coastal areas around the world. Very successfully propagated in the Black Sea estuaries and Azov, introduced by Soviet ichthyologists to the Black Sea in the 1980s, a large Far Eastern mullet pilengas Mugil sojui. In recent years, Pilengas in the Black Sea has been the main fishing site offshore - especially during its spring migration.
Pilengas spring course near the beach VDC Orlenok, depth 1-2m. The dark mass of hundreds of 30-50-centimeter fish is visible from the shore. |
Flora and black Sea underwater cliffs - 40 meters down
Wandering along the shore, you probably noticed a bluish mucous film on the water, stones and moorings. Along the coast of the United States, “mermaid hair” is often found — dark, fleecy, like felt, algae, covering stones and piles. These blue-green algae are the simplest, most primitive of marine plants. Some algae belonging to this group are not blue or green at all, but orange or reddish in color. The Red Sea is so named because it is inhabited by algae from the blue-green class - Trichodesmium erythraeum. The size is much smaller than its name, this plant periodically blooms; at the same time, huge sections of the sea acquire yellow, orange, and occasionally red hue.
In temperate and tropical latitudes, in the lower layers of the tidal zone to a depth of about 9 meters, you can find many varieties of green algae. The most common is a large, luxurious sea salad - Viva lactuca and Viva latissima. It reaches a length of 1.3 meters and grows just below the low tide mark. [Maximum sizes are indicated.] Here you can also find grassy, \u200b\u200btubular Enteromorpha, lacy, fluffy Bryopis sea moss that looks like a sponge, branched Codium and a strange Penicillus algae called a "water brush".
Green algae.
To see most varieties of brown algae, you need to have diving equipment or a boat with a transparent bottom (the water, of course, must also be transparent). The scientific name for this class of algae, Phaeophyceae, means “shadow” or “twilight” plants. They grow at depths of about 30 meters near the rocky shores at all latitudes - from the tropics to the polar countries. True, the cold waters of high latitudes are more to their liking.
Brown algae has more than 1000 species, very different in size and structure. These include tiny, threadlike plants such as Ectocarpus, a 4.5-meter long “chorda line” plant, as well as giant brown algae. A small sea palm tree (Postelsia) grows near the open west coast of the United States, where it has to withstand the blows of powerful waves of the surf. Masses of brown fucus with their characteristic "berries", or air bubbles, bloom large sections of tidal zones with a rocky bottom north of central California and South Carolina.
Gigantic brown algae include kelp, or “damn apron” (Laminaria), which reaches 4.5-6 meters in length, 30-meter sea pumpkin (Pelagophycus) and 40-meter bubble seaweed (Nereocystis) 1. The largest of all plants and the longest of algae, Macrocystis, sometimes attaches to the bottom at a depth of 80 meters, and with its crown touches the surface of the sea. These sea trees form whole underwater forests, and under the thick canopy of their “trunks” with wave-like “leaves” (thalli) they find food and shelter of a myriad of animals.
Rich thickets of brown algae near the Pacific coast are used to produce food, fertilizers and livestock feed. Since time immemorial, these plants have served as food for millions of inhabitants of densely populated coastal regions of Asia and Pacific islands. Currently, residents of these areas eat about 100 varieties of these algae.
Brown algae, as rich in minerals as manure, has long been used, whether fresh or half seasoned, as a fertilizer by farmers in Scotland, Ireland and France. Several factories have been built on the west coast of the United States to process these algae into fertilizers. Not so long ago, at a dairy farm, where algae accounted for 10 percent of the diet, a world milk record was set.
With increasing depth, brown and green algae are replaced by red algae with a length of 1 to 130 meters. They love dim light, which makes them an important source of food for the inhabitants of the mainland shallows. Distributed throughout the oceans, most often these plants are found in temperate climates and in the tropics. These are the most beautiful and amazing representatives of the marine flora, their color is bright and bizarre: orange, red, purple, olive, purple and rainbow.
Red algae.
The purple alga Porphyra looks a lot like a sea salad. This flexible plant is not afraid of blows from the waves of the surf. Indigenous people of North America, Indians, ate algae Porphyra tenera, which is still found in abundance along the coast of America from California to Alaska Bay. In the UK, the crimson Rhodymenia eagerly eats cattle, and the sheep even prefer its grass and go down to the tidal zone to feast on it. People consume this seaweed raw; they chew it like chewing gum or eat it with fish and butter. In many countries, it is poured with milk and served as a seasoning for stew.
