Ocean Report Home Estuaries Recognize the value of our nation's estuaries, and protect and restore them for current and future generations. Estuaries, where fresh water from rivers mixes with salt water from the oceans, are among the most productive environments on Earth.
Estuaries are also popular places to live, work, and enjoy outdoor activities.
Increasing pressures from inland activities and coastal development are causing habitat loss and degradation, fisheries declines, and overall reductions in estuarine health and productivity. Associated physical alterations, such as dredging, damming, and bulkheading, change the natural flow of fresh water to estuaries, affecting water quality, fish spawning, and the survival and distribution of living resources. Removal of vegetation can also affect water quality by causing increased erosion and siltation. Toxic substances and excess nutrients contribute to fish diseases, algal blooms, and low dissolved oxygen and can pose a threat to the health of humans and estuarine wildlife. The introduction of nonindigenous species is also affecting the ecological diversity of many estuarine environments, eradicating naturally occurring species and destroying essential habitat.