As estuaries are areas where fresh and saltwater mix, they are made of many different types of habitats. These habitats include oyster reefs, coral reefs, rocky shores, submerged aquatic vegetation, marshes, and mangroves. Different animals live in each of these different habitats like fish, shellfish, migratory birds, and many more. This diversity makes the food webs complex, and they also rely on the ecosystem as a place to nest and breed. As the salinity of the water changes constantly over the tidal cycle, plants and animals that live in estuaries have developed adaptations to respond quickly to the drastic changes.
Animals survive in estuaries by adapting to the harsh conditions of their habitat. Estuaries either have salt water or fresh water. Animals survive by adapting to live in the different types of conditions and remaining in the regions of the estuaries where they are most comfortable and have consistency.
Fish lay eggs in estuaries because these habitats offer a great amount of food availability for the development of young fish while also providing protection from predators. Estuaries are often used as breeding grounds by many species of fish due to these factors and are considered highly valuable.
Estuaries are important for birds because estuaries offer a mix of nutrients from both the land and sea, creating a rich ecosystem. Since estuaries house numerous species of fish, they also create a food source for birds. Birds also use the beaches next to estuaries for feeding, resting, and breeding.