Dear nature lovers,

Greetings from oikos !

The rivers meet the sea either through an estuary or a delta. Estuaries are tidal mouths of rivers at the sea. The word ‘estuary’ comes from the Latin word ‘aestuarium’ which means the tidal inlet of the sea. This word is further derived from the ‘aestus’ which means a tide.

The estuary is a transition zone between freshwater and marine waters. With the tides and currents, the river gets an influx of marine water from one side and sediments from the other. There is a continuous supply of nutrients to the water column and the sediments, in this zone. This makes it one of the most productive ecosystems on the planet.

Thus, estuaries offer a home to unique plant and animal communities that have adapted to brackish water—a mixture of fresh water draining from the land and salty seawater. Thousands of birds, mammals, fish and other wildlife use estuaries as places to live, feed and reproduce. Migratory birds use estuaries to rest and feed during their journey. Many species of fish and shellfish use estuaries as nurseries to spawn. The estuary offers better security for their young ones to grow.

Like its ecological value, estuaries have an economical value, being used for transport, industries, commercial fisheries and for sand dredging. Moreover, they are great tourist attractions.

However, being located at the tail end of the river, estuaries receive the final impact of human activities throughout the catchment – the garbage, sewage and industrial effluents flow in here. Efforts to reclaim land for urban and industrial development and recreational pressures have a huge impact on estuary and subsequently on the biodiversity it harbours. Considering the ecological and economic importance of estuaries, they are in urgent need of protection and rejuvenation.

Regards,

Ketaki & Manasi

With Team oikos !