Invasive alien species are second only to habitat transformation in documented severity of impacts on biodiversity. Species movements beyond their historic distributions will continue, driven largely by increased volumes of trade and increasingly complex trade routes. In many cases invasion and climate change interact to increase the likelihood of the establishment, growth, spread and survival of species. Assessing and monitoring species distributions and movements is therefore essential for understanding and tracking global change consequences.

Unlike the systematic evaluation and monitoring process in place for tracking the status of threatened species at multiple spatial scales, no such process in currently in place for invasive species. This is in spite of the fact that they arguably pose a greater risk for medium-term economic loss and negative impacts on human and animal welfare than species extinction. Not only is no systematic process in place for tracking the state of global invasion, the variables and metrics for doing so in a standardised way (necessary to underpin a robust observation system) have not been fully developed, widely agreed to, or adopted.

This site provides a framework, guidance and information resources for the development of national observation and monitoring systems for invasive alien species. It was developed using the concept of Essential Biodiversity Variables as a vehicle for identifying the building blocks for National Observation and Monitoring for Biological Invasion that can feed into global monitoring of biological invasion. Some of the tools and resources mentioned are themselves still under development. Nonetheless, there is much that countries can do in the short term to develop their own observation and monitoring systems and contribute to the global effort to better understand, track, manage and report on biological invasions that negatively impact biodiversity.