What is an estuary?

Estuaries are bodies of water in which salt and fresh water mix.
Estuaries have been called the "nurseries of the seas because they provide a safe area for fish, birds, and other animals to raise their young.

Estuaries can be classified based on their geographical features. The four main types include bar-built , coastal plain, tectonic esturary, and
fjord type estuary.

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