This project is inspired by the Global Invasive Species Database's  "One Hundred of the World's Worst Invasive Alien Species" list. Invasion biology is a rapidly changing field as new threat emerge and others are controlled, so this list is not meant to be the be-all-end-all of dangerous invasive species. As it appears that the database has not been updated since 2013, this list is presented while recognizing it may not be fully reflective of the current status of invasions. Ultimately, the goal of these guides is to spread awareness about the problem and make information about invasive species clear and accessible. Hopefully this will inspire you to learn more about the invasive species in your area! 

To learn more about how the species were selected for the list, see this description from the GISD website. 

"It is very difficult to identify 100 invasive species from around the world that really are "worse" than any others. Species and their interactions with ecosystems are very complex. Some species may have invaded only a restricted region, but have a high probability of expanding and causing further great damage (e.g. see Boiga irregularis: the brown tree snake). Other species may already be globally widespread, and causing cumulative but less visible damage. Many biological families or genera contain large numbers of invasive species, often with similar impacts.

 Species were selected for the list according to two criteria: their serious impact on biological diversity and/or human activities, and their illustration of important issues surrounding biological invasion. To ensure the inclusion of a wide variety of examples, only one species from each genus was selected. Absence from the list does not imply that a species poses a lesser threat. For any queries to do with this database, please contact:"

Photo credit (cover photo): Pixabay