An estuary is an area where a river meets the sea and fresh water mixes with salt water. They are usually semi-enclosed and are subject to the tides. However, it is possible to have freshwater estuaries in large bodies of water such as the Great Lakes. Although they do not contain saltwater, the different chemical and physical properties of the lake and river water make for a unique estuarine habitat.
Estuaries are home to a variety of unique plants and animals that have adapted to living in brackish (slightly salty) water. They are among the most productive ecosystems in the world and have even been called the "nurseries of the sea", as many animals rely on them for food, shelter, places to breed, and migration stopovers. For example, juvenile salmon and other species of fish rely on estuaries as a place to grow and become accustomed to brackish water before heading out to the open ocean.
|The Shearstown Estuary.|
The Shearstown Estuary is located between the towns of Bay Roberts and Spaniard’s Bay. The two municipalities signed a joint Municipal Stewardship Agreement in 1997 to protect and conserve the estuary and surrounding habitat. Conservation and stewardship initiatives in the estuary are managed by the Joint Management Committee of the Shearstown Estuary.
Why are estuaries important?
- Offer public access to our ocean-side playgrounds
- Protect shorelines from erosion and flooding
- Physical properties such as water filtration and the mixing of fresh and salt water
- Serve as nursery grounds for many species of birds, fish, and other animals
- Provide energy sources for nearby food webs
- Spawning and foraging habitat for many invertebrates
Estuaries are threatened by…
- Urban and agricultural development
- Poor water quality
- Chemical pollution
- Invasive Species
By understanding these threats we can help protect our estuaries from further damage and perhaps restore degraded estuaries back to flourishing sanctuaries. SAM is building an inventory of wetland restoration opportunities in Newfoundland and Labrador. If you know of a degraded estuary in your community that could benefit from restoration, please contact us.