Marine fish actively drink sea salt water, providing the necessary level of water for normal functioning, and excess salt is removed from the body. The exchange of chlorine ions, sodium, potassium between the organism and the environment both in freshwater and marine fishes occurs through special chloride cells located in the gills, but in freshwater they are used to remove metal ions from water, and at sea to remove them from the body. This process is connected with energy expenditure, as occurs against the gradient. Energy is provided by the involvement of sodium and potassium. “Gill pump” that creates the possibility of a permanent replenishment of salts in freshwater fish, has high efficiency and is able to extract sodium and chloride ions from water millimolar and even lower concentration. Table salt since ancient times used in feed for fish as a preservative, to increase the appetite of fish, improve the absorbability, promote growth, and juvenile anadromous fish in which to prepare for the marine period of life. Due to the active exchange of sodium and chlorine with the environment, their constant intake of fish and disposal along with a large volume of liquid fish not afraid of high content of sodium chloride in the feed. Continue reading
GLASS CATFISH (Indian glass catfish, Kryptopterus bicirrhis; Cuvier et Valenciennes) — in length reaches 10 cm Its second name — som-Ghost — fish received for the transparency of his body. Visible skeleton and all internal organs. Body strongly elongate and flattened laterally. The dorsal fin is extremely small and is located immediately behind the head; below the head is deeply cut almost to the caudal fin extends continuously oscillating, crystal clear anal fin. In the reflected light of the fish glisten all colors of the rainbow, at the same time, remaining so transparent that through them are visible for the fish items.
In addition to transparency, the glass catfish is distinguished by a long anal fin, a pair of long antennae on the upper jaw, small dorsal fin (from one beam) and the position of the head body to the surface.
Glass catfish (Kryptopterus bicirrhis Cuvier u. Valenciennes) lives in South-East Asia, the Great Sunda Islands, Java, Sumatra and Borneo. Continue reading
Part 4. Stabbing fish.
Resting on the sea and face under water with all its inhabitants, man can become damaged from some dangerous fishes, having on his body of the poisonous spines. In addition, eating particular fish, you need to be sure that the meat is not poisonous. While poisoning from meat fish, need to know how to neutralize him.
The Scorpion. Scorpion fish live in tropical and temperate zones, but are also found in Arctic waters. The family of skorinova includes about 330 species of fish. Most of the scorpaenidae are able to masquerade as the surrounding background, changing color, and use of poisonous dorsal spines for protection from enemies. Live in shallow waters, near rocky coasts, in shallow bays, at depths not exceeding $ 100 M.
Fish-dogs. Belong to the order skalozubov (Tetraodontoidea). More than 90 known species of these fish. Different from other the ability to swell. They swallow large quantities of water or air. Individual species are able to bite severely, but the main danger is the meat of the fish-dog. Prepared incorrectly, this fish can cause instant death, as in her skin and internal organs contain a strong neurotoxin. When gutting the insides emit a fetid smell. Continue reading