Fish Encyclopedia: Getting to Know the Classification Features and Aquaculture Value of Fish

Fish are a group of cold-blooded vertebrates that live in water. Their main features are breathing with gills and swimming with fins, and most have scales covering their bodies. As one of the most species-rich groups among vertebrates, fish are widely distributed in rivers, lakes, reservoirs, oceans, and other types of waters. The Fish Encyclopedia is a section that systematically organizes knowledge about the classification, habits, aquaculture, and uses of these organisms.

From the perspective of habitat, fish are usually divided into two major categories: freshwater fish and saltwater fish. Common freshwater fish include black carp, grass carp, silver carp, and bighead carp, while saltwater fish include many groups such as mackerel, trevally, and grouper. It should be noted that not all aquatic animals with "fish" in their name are actually fish. For example, whales breathe with lungs and give birth to live young and nurse them, so they are mammals, not fish. This kind of easily confused issue is exactly the important content that readers care about in the Fish Encyclopedia.

In recent years, some wild fish resources have been threatened by overfishing or changes in the aquatic environment, and some freshwater fish have been included in assessments as endangered or regionally extinct. Reasonably limiting fishing and protecting aquatic ecosystems have become topics of fisheries management and public concern, and they also remind people to pay attention to the sustainable use of fish resources.

In terms of applications, fish are an important source of protein, and models such as pond aquaculture and cage aquaculture are commonly carried out in various places. Scientific feeding techniques and water quality management directly affect aquaculture results and the water environment. Whether they are farmers engaged in aquaculture production or hobbyists who enjoy ornamental fish, mastering basic knowledge about fish helps people understand, use, and protect these aquatic organisms in a more scientific way.