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Threat of Invasive alien species (IAS)

GS Paper 3 

 Syllabus: Environment Conservation


Source: DTE, IE, IPEB

Context: The latest Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES) report, “Assessment Report on Invasive Alien Species and their Control’’ has said that 37,000 alien species have been introduced by humans, including 3,500 invasive species, are linked to 60% of extinctions of global plant and animals


What is an Invasive Alien species?

Invasive alien species are animals, plants, and microbes introduced by humans to new regions, with negative impacts on nature and often on human quality of life.


  • Examples: IAS spread diseases like malaria, Zika, and West Nile Fever through invasive mosquito species.
  • Water hyacinth in Lake Victoria has harmed fish populations and livelihoods.


Key findings of the Report:

  • There are 37,000 alien species introduced to various regions and biomes worldwide due to human activities.
    • Among these, over 3,500 are invasive alien species, responsible for 60% of global plant and animal extinctions.
  • Invasive alien species are one of the five major drivers of global biodiversity loss, Other drivers are:-
    • Land and sea use changes
    • Direct exploitation of organisms
    • Climate change
  • Alien species increasing: The number of alien species introduced by humans has been increasing, driven by factors like increased travel, trade, and global economic expansion.
  • Economic Loss: The annual costs of invasive alien species have quadrupled every decade since 1970, exceeding $423 billion globally in 2019.


Target 6 of the Kunming-Montreal Global Biodiversity Framework aims to reduce the rate of invasive alien species introduction by at least 50% by 2030. While many countries have targets related to managing invasive species, only 17% have specific legislation addressing the issue.


Impact of Invasive Alien Species:

Impact Category Impact Description Examples
Biodiversity Loss Displacement of native species European green crab displacing native crabs in North America.
Competition with native species Zebra mussels outcompete native mussels in freshwater ecosystems.
Alteration of ecosystems and habitats Kudzu vine altering forest ecosystems in the southeastern United States.
Human Health Spread of diseases Aedes mosquitoes spread diseases like malaria and Zika.
Allergies and health risks Ragweed causes allergies in humans.
Economic Impact Agricultural and crop damage The brown marmorated stink bug damages fruit crops.
Damage to infrastructure and property Termites cause damage to buildings.
Food Supply Impact on fisheries and aquaculture European shore crab impacting shellfish beds.
Crop and livestock damage Fall armyworms damaging maize crops.
Cultural and Indigenous Impact Disruption of cultural practices and traditional knowledge Invasive species affecting traditional indigenous practices.
Tourism and Recreation Impact on tourism and recreational activities Invasive plants affecting hiking and camping areas.
Reduction in aesthetic and scenic values Invasive species alter natural landscapes.
Economy and Trade Trade restrictions and losses Bans on wood products due to invasive pests.
Impact on global trade and commerce Trade restrictions on invasive species-infested goods.


To know how Invasive species threaten the wildlife habitats of the Western Ghats: Click Here


The challenge in controlling Invasive Alien Species:

Challenge Description
Rapid Spread and Establishment Invasive species often spread quickly, making it challenging to contain or eradicate them.


Lantana Camara invasion threatens 40 per cent of India’s tiger habitat

Lack of Effective Management Strategies Limited resources and knowledge hinder the development and implementation of effective management strategies.
Environmental Impacts The use of pesticides to control invasive species can harm non-target species and ecosystems.
Species Diversity The dilemma of controlling invasive predators like the mongoose in Hawaii, which was introduced to control rats but also harm native birds.
Globalization and Trade Ballast water from ships transporting invasive species to new regions, like zebra mussels in the Great Lakes.
Inadequate Legislation Gaps in regulations allow the illegal trade of invasive species as exotic pets.
Climate Change Warming temperatures expand the range of invasive plant species into new habitats.
Meeting the KMGBF target by 2030 is uncertain. While progress has been made, measures are insufficient. Only 17% of countries have specific laws or regulations on IAS, and 45% don’t invest in managing them



  • The report suggests an integrated approach involving various sectors like trade, health, and economic development to prevent, detect, and respond to biological invasions.
  • The urgency to address IAS stems from their role in driving plant and animal extinctions. Awareness and action are essential to mitigate their impact and protect biodiversity.
  • Site-based or ecosystem-based management, enforce border biosecurity and import controls etc.


Efforts in this regard:

  • Convention on Biological Diversity (CBD)recognizes that there is an urgent need to address the impact of invasive species.
  • Aichi Biodiversity Target 9and one clause of UN Sustainable Development Goal 15 – Life on Land specifically address the issue.
  • The IUCN SSC Invasive Species Specialist Group (ISSG)aim to reduce threats to ecosystems and their native species by increasing awareness of ways to prevent, control or eradicate IAS.
  • IUCN has developed knowledge platforms:
  • The Global Invasive Species Database (GISD) and the Global Register of Introduced and Invasive Species (GRIIS).



The Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (founded 2012; founder: UNEP, UNDP and FAO; secretariat: Bonn, Germany) is an intergovernmental organization established to improve the interface between science and policy on issues of biodiversity and ecosystem services. It was formed on the basis of the Busan outcome document. It has 143 member States including India.


Insta Links:

Alien plants growing together threatening tiger habitats


Mains lInks:

The effects of invasive alien species on their new surroundings as well as the overall biodiversity of the region are grave. Analyse.