A freshwater wetland is an area of land covered or saturated with water for extended periods of time. The supply of fresh water can come from a nearby body of water, such as a creek or river. In some cases, the land mass may sit on an underground supply of water, called an aqueduct. Some of the most common types of freshwater wetlands include marshes, swamps, and bogs.
A marsh is a type of coastal freshwater wetland that may be periodically covered by less than 6 feet (1.83 m) of water. Most marshes are covered in grass, bushes, and flowers, and are not usually areas that promote tree growth. Marshes are attractive to a wide variety of birds including herons, egrets, and geese. Other animals that live in and around marshes are otters, muskrats, and minks. Marshes are also home to many varieties of frogs, snakes, and turtles.
Swamps are similar to marshes in many ways, but unlike marshes, they do promote excessive tree growth. In addition, unlike marshes, much of the land within a swamp may be fairly dry throughout the year. Swamps are host to many exotic types of animals including alligators, caimans, and nutrias. These wetlands are also home to many types of snakes and turtles, including cottonmouths, water moccasins, and snake-necked turtles. Bears, deer, and raccoons often live in the dense wooded areas that usually surround swamps.
A bog is a type of freshwater wetland that is saturated, but not completely covered by water. In most cases, bogs have soil compositions that are poor and do not promote plant growth. Most bogs are covered in grass, but seldom have shrubs, trees, or flowers. In general, a bog biome is not attractive to most animals; however, in this type of environment, insect life can thrive. Butterflies and dragonflies are often found in bogs, as are several different types of mosquitoes.
Freshwater wetlands can exist in most any type of climate, excluding deserts. They can be found in tropical areas well below the equator as well as in ice-cold polar environments. One of the most important factors in preserving a freshwater wetland is that whatever the climate, it should not drastically change. Extreme changes in rainfall amounts or temperature can have devastating effects on the biome of wetlands. Without favorable weather, the areas can dry up, losing much of the animal and plant life that live within the biome.