invazive

Invasiveness, or invazive in some languages, refers to the tendency of a species or other entity to spread beyond its origin into new areas, often with adverse effects. In ecology, the term usually describes non-native species that establish, spread, and cause harm to native ecosystems, economies, or human health. Not all introduced species become invasive.

Invasive species spread through natural dispersal and human activities such as trade, travel, release of pets or ballast water. They may possess traits that facilitate invasion, including high reproductive rates, broad environmental tolerance, efficient dispersal, and the ability to outcompete native species or resist local predators. The spread often involves a lag phase followed by rapid expansion and population growth.

Impacts of invasive species include ecological disruption—competition, predation, disease transmission, hybridization, and altered habitat structure—and economic costs such as crop losses, infrastructure damage, and expensive control programs. In some cases, invasive species also affect cultural values and biodiversity.

Management of invasives emphasizes prevention and preparedness: risk assessment, surveillance, and rapid response to new introductions; physical, chemical, or biological control methods; and ecological restoration. Policies commonly address quarantine measures, trade restrictions, and monitoring of introduced organisms; successful management requires coordination among scientists, policymakers, and the public.

In medical usage, invasive describes procedures that enter the body or tissues, in contrast to non-invasive techniques. It also describes pathogens or malignant cells that invade and spread through host tissues, contributing to disease progression.

Related terms include native, non-native, introduced, and established species, as well as eradication and containment strategies.