1、 https:/crsreports.congress.gov October 26, 2018Invasive Species: A Brief OverviewAn invasive species is a nonnative (also known as an alien) species that does or is likely to cause economic or environmental harm or harm to human health. The human-mediated spread of species has occurred throughout h
2、istory. However, as society has become more globalized, opportunities for the spread of nonnative and invasive species have increased (e.g., trade shipments can carry species and introduce them to many different regions of the world). In addition, changing environmental, ecological, and socioeconomi
3、c conditions could alter the risk for invasive species introductions in the future. Invasive species include terrestrial and aquatic plants, animals, and microbes. Their introductionwhether deliberate or unintentionalcan pose threats to native animal and plant communities, can lead to ecosystem disr
4、uptions, and may contribute to extinctions of native species. Invasive species also can directly cause or transmit threats to human health. The introduction and spread of invasive species also can result in significant economic costs related to damages as well as management, mitigation, and recovery