Comparison between Tropical Sea and Sea of Japan

 

Life in Tropical Sea

Tropical Sea is in tropic region, where the equator line across the earth. This includes all the areas on the earth where the sun reaches a point directly overhead at least once during the solar year. The ocean is the main influence in creating the tropical marine system climate. There are two main seasons in tropic areas, wet season and dry season. The temperature in tropic areas ranges from 25°C to 35°C. Fishes living in tropical areas are called tropical fish.

Tropical fish have bright vibrant colors on their bodies, and many have interesting patterns on their bodies as well. A typical tropical fish will have a caudal fin after their caudal region, the fin can be either truncated with rounded corners or be round. Most tropical fish have a laterally compressed body, which means they have a flattened shape from side to side. They include both freshwater and saltwater fish species. They are popular aquarium fish because of their bright coloration. Common examples of tropical fish are: Neon Tetras, Betta, Banded Rainbow Fish, Zebra Pleco, Guppy Fish, and Angelfish.

Sea of Japan

The Sea of Japan is a marginal sea of the western Pacific Ocean, between the Asian mainland, the Japanese archipelago and Sakhalin. It has almost no tides due to its nearly complete enclosure from the Pacific Ocean.

The average air temperature on January and February is −20 °C in the north and 5 °C in the south. The warmest month is August with the average air temperature of 15 °C in the north and 25 °C in the south. The sea waters have blue to green-blue color and a transparency of about 10 meters. They are rich in dissolved oxygen (95%), especially in the western and northern parts, which are colder and have more phytoplankton than the eastern and southern areas. This high concentration of dissolved oxygen results in the rich aquatic life of the Sea of Japan.

There are more than 800 species of aquatic plants and more than 3,500 animal species, including more than 900 species of crustaceans, about 1000 of fish and 26 of mammals. Pelagic (oceanic) fishes include saury, mackerel, Jack mackerels, sardines, anchovies, herring, sea bream, squid and various species of salmon and trout. The demersal (sea-bottom) fishes include cod, pollock and Atka mackerel. Mammals are represented by seals and whales, and the crustaceans by shrimps and crabs. Because of the shallow straits connecting the sea with Pacific Ocean, the Sea of Japan has no characteristic oceanic deep-water fauna.

Yet the freshwater fish fauna indigenous to Japan consists of about 115 species and subspecies. Of these, more than 60 species/subspecies of the Cypriniformes (carps, minnows and loaches) and seven species of the Siluriformes (catfishes) are primary-division freshwater fishes strictly confined to fresh water; one species of the Cyprinodontiformes (killifishes), the medaka, is the only representative of the comparatively salt-tolerant secondary division; and the remaining, including diadromous fishes and freshwater species derived from marine groups, such as the Japanese forms of freshwater eels, salmons and chars, ayu sweetfish, sticklebacks, perciforms, and sculpins, are freshwater fishes of the peripheral division.