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Wetlands and Estuaries. What is a Wetland?. Wetlands are areas where water covers the soil, or is present either at or near the surface of the soil all year or for varying periods of time during the year, including during the growing season. Why are Wetlands Important to Animals?.
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What is a Wetland? • Wetlands are areas where water covers the soil, or is present either at or near the surface of the soil all year or for varying periods of time during the year, including during the growing season.
Why are Wetlands Important to Animals? • Wetlands are among the most productive ecosystems in the world, comparable to rain forests and coral reefs. • They provide great volumes of food that attract many animal species. • Form the base of the food web and feed many species of fish, amphibians, shellfish, and insects. • Many species of birds and mammals rely on wetlands for food, water, and shelter, especially during migration and breeding. • Wetlands retain excess nutrients and some pollutants, and reduce sediment that would clog waterways and affect fish and amphibian egg development.
Why are Wetlands Important to People? • Filter water that we swim in and get food from. • Form a “sponge” to absorb excess water and control flooding and help control erosion. • Food Supply: Wetlands are nurseries for food we eat such as fish, shrimp, crab and oysters. • Jobs: Many people in our area support their families fishing, shrimping and oystering. • Local Economy: Many local businesses depend on the seafood industry for their revenue. • Tourism and sport fishing tournaments also rely on these wetland areas to provide us with recreation, hunting, fishing, photography and bird watching, just to name a few.
Types of Wetlands • Swamps • Marshes • Bogs
Swamps • A swamp is a wetland that is dominated by trees and shrubs. • Swamps are often near rivers or streams. • These rivers and streams sometimes flood, and the water from the flood carries nutrients to the swamp.
Marshes • A marsh is a type of wetland which is distinguished from other wetland varieties by having an assortment of grasses, reeds, and sedges, without large bushes and tall trees. • A marsh can be salt or fresh water, and often has large spaces of open water which are heavily colonized by birds. • A marsh provides vital habitat to many plant and animal species as well as protecting neighboring areas of land from flooding, and in the case of saltwater marshes, excessive salination.
Bogs 1. A bog is a wetland type that accumulates a deposit of dead plant material. 2. Pitcher plants are also found in bogs.
ESTUARIES • Fresh water from the Mobile-Tensaw River Delta is mixed with saltwater from the Gulf of Mexico. • Our Mobile Bay is an estuary. • Estuaries are partially enclosed bodies of water where freshwater meets salty ocean water. • Brackish water is a mix of fresh and salt water. • Estuarine environments are among the most productive on earth.
Why are Estuaries Important? • Habitats for a variety of marine life, birds and mammals. Safe place for small creatures to grow to maturity, such as fish and shrimp. • Migrating birds often make estuaries their winter homes and resting spot. • Plants help against erosion. • Filter water • Absorb Flood water • Valuable natural laboratories for scientists and students.
Human Impact on Estuaries Human impact on estuaries includes reclamation of tidal land by: • pollution from sewage • solid waste • increased sedimentation filling the estuary • Humans are the #1 threat to estuaries.
Alabama Red-bellied TurtleAlabama State Reptile • Found only in areas along the causeway in the upper bay and lower delta.
Gailliard Island: Located in Mobile Bay • Created from the dredging of the Theodore Industrial Canal. • Became a home for brown pelicans • Brown pelican were endangered • Gaillard Island helped bring back populations by giving the birds a place to lay eggs and raise young
