Salient Features :

The marine biomes, the biggest aquatic biomes in the world, support a great diversity of life and variety of habitats. They cover about 70% of the earth and include the Pacific, Atlantic, Indian, Arctic, and Southern ocean, as well as many smaller Gulfs and Bays. Mud flats, rocky and sandy shores, barrier islands, salt marshes, and mangrove forests also come under the category of marine biomes.

Coral Reefs: Corals are considered to be a separate biomes, even though they are located within the ocean. Most people mistake corals for plants, even though they are animals that are related to jellyfish. Reefs provide food, shelter and nursing grounds to the aquatic animals. Found mostly in tropical and subtropical oceans, corals are located in shallow areas at a depth of less than 150 feet. However, some coral reefs extend even deeper, up to about 450 feet deep such as the coasts of East Africa, South India, Australia, Florida, the Caribbean, and Brazil. In India, major coral reefs are found in Gulf of Mannar, Gulf of Kachchh, Andaman and Nicobar and Lakshadweep Islands.

Estuaries: Estuaries are semi-enclosed coastal bodies, where seawater mixes with freshwater, as they have the sea at one end and a river at the other. Estuaries are sometimes called bays, lagoons, harbours, or sounds. Freshwater and salt marshes, sandy beaches, mud and sand flats, rocky shores, and mangrove forests are few examples of the different types of habitats that are found in and around estuaries.

The main reasons for the formation of estuaries are rising sea level, movement of sand and sandbars, melting of glacial processes; and tectonic processes. Different types of estuaries have different water circulation, based on ebb and flow of tides, differences in the density of water, and wind. Estuaries experience rise and fall of waters once or twice daily due to the lunar tides. Most of India’s major estuaries are located on the east coast in the Bay of Bengal. The estuaries on the west coast are smaller, Mandovi and Zuari estuaries are two examples of estuaries on the west coast of India.

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Flora & Fauna :

Marine biomes provide habitat to corals, seaweeds, marine algae, sea grasses, and mangroves. Seals, whales, dolphins, dugongs, otters, walruses, and polar bears are some of the commonly found marine animals. The blue whale is the biggest animal on earth.

Coral reefs: Fish, turtles, sea snakes, sharks, and dugongs are commonly found in this biomes. Mangroves and seagrasses are the only two types of plants that are found within coral reefs. Seagrasses are often found in shallow, and sheltered marines. Mangroves are the only terrestrial plants that can tolerate direct immersion in sea water. They can survive in saline conditions due to their specialised salt-filtering roots and salt-excreting leaves.

Estuaries: Estuaries have soil that are rich in nutrients and a variety of plants grow here. Animals common to this biomes are sea birds, fish, crabs, lobsters, clams, and other shellfish, and lots of reptiles. Estuaries are often referred as the nurseries of the ocean. Sandpipers, great blue herons, great egrets, and green herons are few examples of birds found here.