Species introduced on purpose or accidentally from other places can invade Alaska and harm the economy, environment, and even human health. Once these invaders arrive, it can be extremely difficult to control them without also hurting native species. The sooner you find them, the better chance there is to control them. That is why we keep a sharp eye out for new invaders and work with the State and other partners to prevent invasions.
Each species evolves in the presence of others and develops a natural pattern of relationships with these other species – as competitors, predators, disease organisms, and so on. Most often species are also limited by physical or other barriers. For example, land is a barrier to the spread of aquatic species just as water can be a barrier to the spread of many land animals. Within these barriers, natural systems (ecosystems) begin to form.
