The land area from which fresh water drains into the estuary is its watershed. Significance Estuaries are significant to both marine life and people. They are critical for the survival of fish, birds, and other wildlife because they provide safe spawning grounds and nurseries. Marshes and other vegetation in the estuaries protect marine life and water quality by filtering sediment and pollution. They also provide barriers against damaging storm waves and floods.
Estuaries also have economic, recreational, and aesthetic value.
People love water sports and visit estuaries to boat, fish, swim, and just enjoy their beauty. As a result, the economy of many coastal areas is based primarily on the natural beauty and bounty of their estuaries. Estuaries often have ports serving shipping, transportation, and industry. Healthy estuaries support profitable, commercial fisheries. This relationship between plants, animals, and humans makes up an estuary's ecosystem.