The greatest threat to biodiversity today is habitat loss. The habitat for wild plants and animals is shrinking at alarming rates. Human needs, often overrule the needs of wildlife. It is obvious that our species depends on the health of other species. If you think about the fact that nearly half of all U.S. wetlands, which are destroyed over the last 200 years, where considered useless. In reality they did not only provide essential habitat for many species, but also act as buffers against flooding and erosion and help to filter sediments and pollutants from the water. We have wasted a lot of important habitat.

Species that are brought to an area where they naturally do not occur, are called alien, introduced, or exotic species. These plants can have devastating effects on existing biodiversity, as they compete with, and sometimes destroy, the native species. For example, native plants are literally contravened and eaten by introduced animals, such as goats and pigs. Therefore these plants are now extinct in Hawaii, and some other parts of the country. Introduced plants, like kudzu, can have the same impact. They can overcrowd , and destroy the native species. Although Hawaii appears very lush and green, most areas tourists see, do not contain native species anymore.