2017 alien invasion drivers#

However, in the second call, besides stressing the need to respond to indirect drivers of biodiversity loss (e.g. With respect to biodiversity, the 1992 warning explicitly highlighted deforestation, species loss, and climate change but did not mention invasive alien species (IAS). The original 1992 call was supported by more than 1,700 scientists, while 25 years later over 15,000 scientists added their signatures to the recent declaration (Ripple et al., 2017).Ĭomparing the two documents reveals an important difference in focus as regards biodiversity loss and species extinctions.

Indeed, they concluded that most of these problems had worsened. ( 2017) evaluated the human response based on their analysis of time‐series data and concluded that humanity had failed to make sufficient progress over that period in dealing with the environmental challenges. They cited concerns regarding ozone depletion, freshwater availability, marine life depletion, ocean dead zones, forest loss, biodiversity destruction, climate change, and continued human population growth (Union of Concerned Scientists, 1992). Nearly three decades ago, a community of eminent scientists warned that humans were on a collision course with the natural world. (1) Relevance to Scientists' warning initiative Countries can strengthen their biosecurity regulations to implement and enforce more effective management strategies that should also address other global changes that interact with invasions. Improved international cooperation is crucial to reduce the impacts of invasive alien species on biodiversity, ecosystem services, and human livelihoods. However, in many countries, invasions receive little attention. There have been long‐term successes, such as eradication of rats and cats on increasingly large islands and biological control of weeds across continental areas. For some nations, notably Australia and New Zealand, biosecurity has become a national priority. Scientific evidence has identified policy strategies to reduce future invasions, but these strategies are often insufficiently implemented.

These biodiversity and ecosystem impacts are accelerating and will increase further in the future. Many invasive alien species also change ecosystem functioning and the delivery of ecosystem services by altering nutrient and contaminant cycling, hydrology, habitat structure, and disturbance regimes. Invasive alien species break down biogeographic realms, affect native species richness and abundance, increase the risk of native species extinction, affect the genetic composition of native populations, change native animal behaviour, alter phylogenetic diversity across communities, and modify trophic networks. In many cases, such impacts become apparent or problematic only when invaders are well established and have large ranges. Invasions have complex and often immense long‐term direct and indirect impacts. Synergies with other global changes are exacerbating current invasions and facilitating new ones, thereby escalating the extent and impacts of invaders. The numbers of invasive alien species – the subset of alien species that spread widely in areas where they are not native, affecting the environment or human livelihoods – are increasing. Biological invasions are a global consequence of an increasingly connected world and the rise in human population size.

2017 alien invasion