The Caspian sea should be considered a sea or a lake? Because it is not connected directly with the ocean, according to the strict requirements of geography, therefore, is the lake. But the water in this lake is salty, marine. Therefore, we call this the closed reservoir of the sea. Lake Baikal is a lake or the sea? Baikal is also considered the lake as it is fresh water.
Fish who spend their lives performing in high salty waters of the sea; fish, living from birth to death in fresh water – freshwater.
And the fish that live in the coastal parts of seas, where flow of fresh water rivers? They are usually considered as brackish.
In the Caspian sea is the real sea herring, which live and breed in the sea and in fresh water will never enter. All three groups of Caspian herrings that peacefully exist in one place, related to each other, but they differ in their appearance and biological features: first marine, second is saltwater, third freshwater.
There are species of herring, living in the sea for spawning going far in the river. These fish have a characteristic title: “diadromous fishes”. Continue reading
Rear Admiral Viktor Dygalo Ananiyovich — a man who was born by the sea, and then gave him most of his life. In 1944, eighteen-year-old boy, he participated in the fighting at the ships of the black sea fleet, in 1945 — the Victory Parade. Then there were twenty years of service on submarines, command of a division, composed tragically died in March 1968 at the Hawaiian Islands missile submarine K-129.
Experienced sailor extensively in the seas and oceans, visited ports in Indonesia, Malaysia, Africa and Europe, twice crossed the equator. He watched not only marine animals in the open ocean, but in the gigantic aquariums in Singapore and Suez.
Knowledge of the underwater world and the impressions reflected in the article about those ocean creatures that should be feared.
Candidate of naval Sciences, Professor V. DYGALO.
When people talk about the dangers hidden in the ocean, people think of sharks. The mere mention of them evokes fear, before my eyes immediately gets the image of a giant shark from the famous American movie “Jaws” filmed in the early 1970s, based on the novel by Peter Benchley.
Actually shark, includedirectory species, and a total of more than 250, do not attack people. Just behave and other toothy predators of the sea-giants. But we are not talking about them. Continue reading
Som is a major accesata fish that live in fresh water. Belongs to the family of catfish. This species is widely distributed in Europe. The habitat covers the majority of European countries except Spain, the UK, Italy, Norway. In the North the fish can be found in the southern water area in Sweden and Finland. In the South area of distribution reaches the coastal waters of the Black and Aegean seas. In Russia fish is spread up to the Urals. It is also found in Asia. The Aral sea basin. Members of the species and swim in the salty waters of the Black, Caspian and Baltic seas. The highest concentration observed at the mouths of large rivers and reservoirs. In the upper reaches of rivers is rare.
Body soma long. In front of it is rounded, and the rear part is compressed laterally. The head is broad and flat, eyes small and shifted to the frontal area. In the mouth has many small teeth. In the upper jaw are long whiskers one on each side. In the lower jaw there are 2 short whisker on each side. A long anal fin which reaches almost to the caudal fin. The dorsal fin is small, sharp and shifted towards the head. The pectoral fins are broad. Their fish creates a vortex in the water to disorient the victim. The skin is slippery and smooth. Scales out of it.
Body colour not monochrome. Back cantenna, almost black. The flanks are greenish-brown and diluted by lighter spots. The belly is light gray. It is more correct to call it off-white. In waters with flowing water the fish is lighter colored, and in stagnant waters it is much darker. Continue reading