One of the most important reasons is the high phosphate and nitrate content of West Coast waters. This increases the production of plankton, which is the staple food of juveniles and juveniles. On the other side of the east coast and Bay of Bengal, circulation is less pronounced, and marine features are partially lost due to the occurrence of more rivers (Dias Carlos, et al 2006). This part of India's marine fisheries is still in the experimental stage. Several exploratory studies have been conducted on deep-sea fish abundance on both coasts, suggesting that deep-sea fisheries, like coastal fisheries, may have significant commercial and economic value (Drees, et al 2005). There are various deep-sea fishing bases in Bombay, Kerala, West Bengal and Visakhapatnam, some of which are operated with the support of the Japanese and US governments. To find ways and means to use deep sea water as a productive place. Marine fisheries relate to the breeding and catching of fish in waters. Fish, the most important components of the marine food web, provide food for marine mammals. Besides their role in the marine environment, fish also serve as an important source of protein in the human and animal diets for both rural and urban populations. The fisheries sector directly benefits millions of people (Durrani, 1995). It makes a significant contribution by directly and indirectly providing livelihood, generating income and providing fore. About 240 species contribute to marine fisheries. Examples: sardines, mackerel, ribbon fish, anchovies, groupers, cobia, tuna, etc. Not all marine fish are the same.
They are divided into herbivores, carnivores and omnivores, each requiring a different type of food.
Marine fish drink water Freshwater fish does not actively drink water, but rather absorb water through their skin and gills. Saltwater fish actively drink seawater (Heemels, et al 2009). Their gills process water and extract salt. Fish can drown in water fish need oxygen, and they can suffocate and drown as they require a consistent intake of oxygen to survive. Their gills absorb oxygen from water molecules as water passes through the gill membranes. Sharks are the only fish that have eyelids- All sharks have at least two eyelids, an upper lid and a lower lid; however, these eyelids can't move, which means sharks can't blink. Black tip female sharks are capable of self-reproduction this phenomenon is called Parthenogenesis and results in the production of female offspring. This happens only when a female cannot find a partner for reproduction (Ratschan, 2014).