THE THEMATIC ASSESSMENT REPORT ON INVASIVE ALIEN SPECIES AND THEIR CONTROL
13SUMMARY FOR POLICYMAKERS
negative impacts and 8 per cent positive impacts on nature 
caused by invasive alien species.
KM-A5 Overall, policies and their implementation 
have been insufficient in managing biological 
invasions and preventing and controlling invasive 
alien species {A7, A8}. Up to 2020, only partial progress 
was made towards international goals and targets (e.g., 
Aichi Biodiversity Target 9 and Sustainable Development 
Goal Target 15.8). While most countries have targets related 
to the management of biological invasions within their 
national biodiversity strategies and action plans, effective 
policies are often lacking or inadequately implemented. 
Eighty-three per cent of countries do not have national 
legislation or regulations directed specifically toward the 
prevention and control of invasive alien species. Policy 
relevant to biological invasions is also fragmented within 
countries and across sectors. To date, capacity to respond 
to biological invasions has varied widely across regions, 
with nearly half of all countries (45 per cent) not investing 
in management of invasive alien species (SDG indicator 
15.8.1). Differences in perception, including conflicting 
interests and values, of the importance and urgency of 
the threat of invasive alien species, coupled with lack of 
awareness of the need for a collective and coordinated 
response, as well as gaps in data and knowledge, can 
hinder the management of invasive alien species. Economic 
development policies and those aiming to manage other 
drivers of change sometimes facilitate biological invasions. 
Demographic drivers also facilitate the introduction and 
spread of invasive alien species while acknowledging that 
drivers differ across regions and level of impact. The lack 
of border biosecurity (such as inspections undertaken by 
quarantine officers of commodities, goods and people) 
in one country weakens the efficacy of such measures in 
other countries.
B. Globally, invasive alien species 
and their impacts are increasing 
rapidly and are predicted to 
continue rising in the future
The threats from invasive alien species are 
increasing in all regions of Earth and are 
predicted to do so in the future. Even without 
the introduction of new species, existing 
populations of invasive alien species will 
continue spreading through all ecosystems. 
Amplification of and interactions among 
direct and indirect drivers of change will 
profoundly shape and exacerbate the future 
threats from invasive alien species.
KM-B1 Many human activities facilitate the 
transport, introduction, establishment and spread 
of invasive alien species {B9, B11, B12, B14} 
13SUMMARY FOR POLICYMAKERS
The thematic assessment report on
INVASIVE ALIEN SPECIES
AND THEIR CONTROL
KM-A1 People and nature are threatened by 
invasive alien species in all regions of Earth 