Answer:
Invasive species are usually defined as those species which, when introduced into an ecosystem becomes dominant at a faster rate. They does not belong to the native ecosystem. It directly affects the existing biodiversity in the marine as well as the aquatic ecosystem. For example, Zebra mussels, Burmese python and Green crab.
These species are sometimes added into the marine and other aquatic ecosystem due to the releasing of the ballast water through the ships in the oceans, and it takes place either intentionally or accidently.