Invasive alien species (IAS) pose a significant threat to forest ecosystems by disrupting ecological networks and competing with native species. Forest habitat patches and corridors designed to enhance connectivity and biodiversity can unintentionally promote the dispersal of IAS, further compromising the ecological integrity of the forest ecosystem. This chapter discusses two main aspects related to IAS and forest connectivity: (1) the spread of IAS in the landscape and their impacts on native species and (2) the consequences of IAS on forest connectivity. Effective management of IAS is crucial to improve connectivity for native species while restricting the spread opportunity for aliens and preserve biodiversity. Ideally, a site-specific risk analysis should precede conservation or restoration efforts, determining the potential impact of IAS on the respective habitat patch’s structural and functional connectivity, and vice versa. Furthermore, this chapter explores management strategies to control IAS, including physical removal, biological control, and monitoring. Citizen involvement and remote sensing play vital roles in supporting management actions, IAS detection and long-term monitoring, and habitat connectivity. Including stakeholders such as forest owners and managers in such actions ensures a collaborative approach to safeguarding forest ecosystems from the threats posed by IAS.
