From the Document: "An 'invasive species' is a nonnative species that does or is likely to cause economic or environmental harm or harm to human health. Invasive species impact terrestrial and aquatic--including marine and freshwater--systems. As society has become more connected, opportunities for the spread of invasive species have increased (e.g., navigation activities can transport species and introduce them to multiple different watersheds and waterbodies). After introduction, invasive species may become established and spread; it can be costly and difficult (or impossible, in some cases) to control or eradicate them. Many federal and nonfederal agencies managing land and water undertake efforts to prevent the introduction and spread of invasive species or, upon detection of an invasive species, devote resources to control and eradication efforts."
CRS In Focus, IF11666
Congressional Research Service: https://crsreports.congress.gov/