All habitats have four important components (parts) for wildlife: shelter, water, food, and space. Most of the time, people only think of shelter when considering habitat, but the other three components are just as important, and an organism cannot survive without all four.
Shelter describes the structures which an organism lives near, around, on top of, or inside. A home can be considered shelter, such as a burrow, tree cavity, or space beneath an old log. A nest is also shelter, such as a bird's nest or beehive. Another type of shelter is "cover." Cover may not be a home or nest, but simply an arrangement of plants, rocks, dead leaves, water, or shade that an organism can hide in or move undetected by other organisms. Shelter can also be anywhere that an organism uses to escape weather or other dangerous conditions.
Water is important to all forms of life, and without getting enough water in some way, an organism will die. Water is therefore an important part of any habitat.
Food is also essential. Food comes in many forms for many different organisms. Food may be a plant that a rabbit munches on; or, to a hawk, the rabbit is the food. Nutrients in the soil are food for plants.
Space is often overlooked as a component of habitat, but all organisms must have it to be healthy. If too many of one kind of animal lives in the same area eating the same kinds of food, using the same shelter, and drinking the same water, these things will soon be used up and none of the animals will survive. The same goes for plants, which crowd each other as they reach for light (with branches), water (with roots), and nutrients (also with roots).
Below are links to ten different types of habitats found in Northern Virginia and other parts of the world. Click the habitat you want to learn more about. Remember, these are just some examples of habitat. Other kinds exist, and often habitats blend together; for example, a river may flow through a meadow or a forest, a marsh may have a pond in it, or a neighborhood could contain many flower gardens.