the time between when an alien species arrives in a new area and the onset of the phase of rapid, or exponential, increase. Multiple factors are frequently implicated in the persistence or dissolution of the lag phase in biological invasions, including an initial shortage of suitable sites, the absence or shortage of essential mutualists, inadequate genetic diversity, and reduction in competition or predation (due to other alterations in the resident biota)

animals, plants or other organisms introduced directly or indirectly by people into places out of their natural range of distribution, where they have become established and dispersed, and generating an impact on local ecosystems and species (IPBES, 2016); see Chapter 1 for further discussion). Invasive alien species are a subset of established alien species that have negative impacts.

the amplification of impacts of invasive alien species through community-level processes in which there is a cascade of effects, positive feedback loops, arising from the interactions amongst species, in this case alien species, which ultimately affect ecosystem functions

stages (transport, introduction, establishment, and spread) that a species must pass through on the invasion continuum from native to (invasive) alien species, recognising the need for a species to overcome the barriers (geography, captivity or cultivation, survival, reproduction, dispersal and environmental) that obstruct transition between each stage

areas of high alien species richness relative to other regions with similar biogeographic characteristics (O’Donnell et al., 2012). Biodiversity hot spots of diversi?cation and species richness are defined as geographic regions with high diversi?cation rates or high species richness, respectively, while conversely cold spots are geographic regions with low diversi?cation rates or species richness

the potential increase in biological invasions at a site over a particular time frame in the absence of any interventions (Rouget et al., 2016). It is composed of the number of new species that will be introduced (introduction debt), the number of species that will become invasive (species-based invasion debt), the increase in area affected by invasions (area-based invasion debt), and the increase in the negative impacts caused by introduced species (impact-based invasion debt)

depiction of the different stages of invasive alien species management from prevention to early detection and eradication, containment and adaptive management (Invasive Species Centre, 2021). The curve shows that eradication of an invasive alien species is less probable and more costly as it spreads over time. Choosing a management action relies on where a species is on the invasion curve.

areas of low alien species richness relative to other regions with similar biogeographic characteristics (O’Donnell et al., 2012). Biodiversity hot spots of diversi?cation and species richness are defined as geographic regions with high diversi?cation rates or high species richness, respectively, while conversely cold spots are geographic regions with low diversi?cation rates or species richness

a suite of processes that result in the introduction of a species from one geographical location to another. It means: 1) geographic routes by which a species is moved outside its natural range (past or present); 2) corridors of introduction (e.g., road, canal, tunnel); and/or 3) human activity that gives rise to an intentional or unintentional introduction. More than one vector (see definition of vector below) within a pathway may be involved in a transfer of species

an integrated approach to planning and implementing future options to reduce the spread and limit the impact of biological invasions considers the fact that (1) multiple levels of governance are relevant, (2) diverse actors and decision-makers are involved, (3) the invasion process is multi-staged, and (4) drivers of invasion are multiple and interacting