A wetland is land area saturated with water. This saturation of water determines the soil development and the types of plants and animals living there. Natural wetlands include marshes, billabongs, freshwater lakes, ponds, farm dams, swamps, lagoons and estuaries. Wetlands are important for many reasons. they provide the habitat for waterbirds, frogs, invertebrates and fish. Both natural and artificial wetlands are a refuge for many plants and animals.

Wetlands improve the quality of water in a number of ways. Still and flowing water filters sediments in deep areas, while the algae screens out pollutants. The recycling of nutrients in wetlands is a means of removing nutrients and stabilizing metals in water. Bacterial contamination is common in wetlands, the levels of these harmful contaminants can be reduced by the ultraviolet rays of the sun. A chemical process takes place in wetlands which encourages the breakdown of organic matter by tiny microorganisms, this encourages the binding of clay and soil.

Some wetlands are seasonal. The dry season may be essential to the life of a wetland. Too much water can encourage plant overgrowth. Plants may take overin ponds needed by some aquatic wildlife and birds. Preventive measures need to be taken to avoid loss of seasonal wetlands. When a wetland is stewarded by man, attention must be given to the importance of an adequate water supply.

Wetlands support plant life, insects, and provide the habitat for many birds.Worldwidee there is only an estimated 45% to 50% of former wetlands remaining today. In Hawaii, less than 10% of former wetlands exist. This loss of habitat endangers four species of birds found only in Hawaii, the Hawaiian Coot, Black Necked Stilt, Common Moorhen, and Hawaiian Duck (Koloa). Other migratory birds may also become endangered as the wetlands disappear. Today, many Hawaiian streams and marshes are dewatered, or low in water. People have taken water away from marshes and stream. Dewatered areas threaten the existance of water birds, insects, and plants.