Fisheries Science is a department of marine science that offers with studies on the existence history and state of fish stocks. The term ‘existence history’ refers to the widely wide-spread biology of a fish stock. The time period ‘state of a fish stock’ refers to the range and weight of fish in the stock i.e. current stock biomass in tonnes. 

Aquaculture is an important farming activity in EU. Farming of fish has increased in recent years and science to access welfare is evolving. Fish nurture in aquaculture systems faces numerous welfare challenges. The development and implementation of appropriate production facilities to ensure the well-being of growing numbers of farmed fish are critical. A key welfare problem for farm fish is infection by disease and parasite. To align welfare issues should follow some welfare rules for freedom fish like Freedom from hunger and thirst, discomfort, pain, and injury, from fear and stress.

Aquaculture and fishery are one of the important sectors in the economy. Sustainable aquaculture is a dynamic concept and sustainability vary with species, location and, state of knowledge and technology. Aquaculture should have environmental as well as economic sustainability. Sustainability of species depends on feeding and lifecycle habitats. Aquaculture can improve the sustainability of small scales farms. Multiple uses of water are an important aspect of the sustainable aquaculture system.

Aquacultures are simply defined as aquatic organisms. Fish require the same nutrients that all animals require for health and reproductive growth. It includes proteins, minerals, and vitamins. The main objective of aquaculture nutrition is to balance the food portion which should be composed of fish meal and fish oil at the average rate. Improved efficiencies in aquatic nutrition and aqua feed development are essential to the long-term development of local aquaculture industry.

Shellfish farming helps to improve sediment quality by loosening and dispersing silt and muck, and helps add oxygen to bottom waters and sediments. Filter-feeding bivalve molluscs are an essential link between the bottom-dwelling aquatic communities and phytoplankton production in the water column. Shellfish are highly efficient water filters that directly remove particulate material thus reducing turbidity and both directly and indirectly removing nitrogen and other nutrients. Via this process, these highly efficient water purifiers remove or reduce organic matter, nutrients, silt, bacteria and viruses, and improve clarity and light transmission which, in turn, improves the condition of critical habitat, including survival of critical habitat species such as sea grasses and other submerged vegetation.

Impacts of aquaculture on the environment are increasing. The main influence of aquaculture on water quality is to increase the suspended substances and the nutritional salts in water. It is an important issue as aquaculture expands globally. In South East Asia shellfish are produced heavily and poorly managed. Farmed fish are generally free from environmental contaminants such as heavy metals. Environmental impacts of aquaculture are dependent upon the species farmed.

The infectious disease poses one of the most significant threats to successful aquaculture. Negative environmental effects may occur serious oxygen shortage caused by disintegrating natural substances. There will be no treatment for viral diseases. Most of the fish diseases are restricted to fish and poses no risk to handlers. It’s essential to report any infections or diseases to fish as quickly as time permits. This leads to early administration and regulation of pathogens for the regular environment.

The Fishery Resource Analysis and Monitoring, monitors ground fish and halibut fishing activities in the Federal fisheries off Alaska and conducts research associated with sampling commercial fishery catches, estimation of catch and by catch mortality, and analysis of fishery-dependent data. The division is responsible for training, briefing, debriefing, and oversight of observers who collect catch data onboard fishing vessels and at onshore processing plants and for quality control/quality assurance of the data provided by these observers.

Aquatic Pathology studies infectious diseases of cultured and wild fin fish and shellfish, particularly those caused by viruses and bacteria, in order to reveal infection mechanisms and develop effective control measures of the diseases.

The variation in technologies is used to observe live fish in the industry and is limited. New techniques are for the treatment of diseases. The technologies used in aquaculture are relatively simple and based on modifications that improve survival rates of targeted species. Fish farming includes establishing fish in place of growth.

Aquaculture Economics and Management provides a detailed and specific set of guidelines for using economic and financial analysis in aquaculture production. By discussing key issues such as how to finance and plan new aquaculture business, how to monitor and evaluate economic performance, and how to manage capital, labor, and business risk, the book equips aquaculture professionals, researchers, and students with important information applicable to a wide range of business decisions. It address each stage of developing an aquaculture business, including financing, marketing, and developing a business plan to managing cash flows and analyzing financial statements. 

Marine ecology is the logical form of marine life population, surroundings among organisms including biotic and abiotic components. Marine ecosystems are vital for the overall health of both marine and land-dwelling environments. Biological oceanography shows the effect on organisms by oceanography systems. This is like marine biology. It focuses on the micro-organism, ecosystem and affects the environment.

Genetic biodiversity helps produce the variety of shapes, sizes, behavior, and colours that make aquatic species valuable and interesting. It also allows species to adapt to new farming systems and new habitats. Without genetic biodiversity there would be no special varieties or breeds of aquatic species eventually species would go extinct as they would be unable to cope with climate change and other changes to their environment. 

Aquatic resources and management provide the protein in income communities and ecosystem maintains agriculture and health. These resources and management are focused on aquaculture and oceanic region and related fields. It represents half of the aquatic creatures for better improvement. These aquatic resources and water management is done for further improvement of the environment.

Engendering security in aquaculture focused on multiple facets of the fish value chain and society. These facets include food security and nutrition, access to research, fair livelihoods, and safety within the household and climate change disasters. Genders equality champions should be supported, and women encouraged to speak up and act on their own behalf.

The Interaction between aquaculture and fishery is done in different unique ways. These two communications are different forms of man inventions in the life cycle and aquatic organisms. The relevance of interactions between two sectors became more evident as the process of transition from fishing to farming and has reached a point. Aquaculture is related to various aqua creatures. Natural connections can create distinct ways.

Fisheries biology and management is the study of marine environments and the monitoring and management of their living resources. The field includes ecological studies and analysis, population modeling, data collection, and working with communities to ensure sustainability.

Recirculating aquaculture systems operate by filtering water from the fish or shellfish tanks so it can be reused within the tank. This dramatically reduces the amount of water and space required to intensively produce seafood products. The steps in Recirculating Aquaculture Systems include solids removal, ammonia removal, Co2 removal and oxygenation. 

Aquatic Toxicology is a multidisciplinary branch which includes study of natural and synthetic toxicants and their effects that are leading to toxicity of aquatic systems. It is a field of Science that focuses on study of various chemical and physical toxins that effect biological living organisms. Source of aquatic toxicology may also include persistent toxins such as PCBs, DDT, TBT, pesticides, furans, dioxins, phenols and radioactive waste, by direct discharges via industrial and urban effluents, surface run off and indirectly from aerial fallout.

In recent years world aquaculture production has been increased with innovative and technological developments within fisheries sector and scaled up in world total fisheries production. This increasing aquaculture production quantity depends on production of new species in aquaculture, new raw material production and processing techniques in fish feed manufacturing, innovative production systems and technologies, biotechnological developments.