BIOLOGICAL INVASION (Syllabus: GS Paper 3 – Environment)

Context: In recent news, the phenomenon of biological invasion has gained attention as plants and animals increasingly move across habitats and ecosystems, either through human intervention for profit or inadvertently during global shipments.

Biological Invasion

• About: They are a significant force driving change across various dimensions of life on Earth.
• Global Status of Invasions: Invasions occur when species colonize new, isolated geographic regions, and globally, alien species rank among the top five major drivers of change alongside land- and sea-use change, direct exploitation, climate change, and pollution.
• Extinction Threat: No place on Earth remains untouched by biological invasion, leading to the extinction of thousands of species, with at least 218 invasive species causing over 1,200 local extinctions.
• Negative Impact on Native Species: Approximately 85% of the effects of biological invasions on native species are detrimental, as highlighted in the IPBES assessment report.
• Rising Economic Burden: The economic cost of biological invasions has been increasing fourfold each decade since 1970, indicating a growing challenge for global economies.

Invasive Alien Species

• About: It  stand as one of the five primary direct drivers causing biodiversity loss worldwide, alongside land and sea use change, direct organism exploitation, climate change, and pollution.
• Continuous Rise in Alien Species: The number of invasive alien species has been on a continual ascent for centuries, affecting all regions and ecosystems across the globe.
• Dominance of Water Hyacinth: The water hyacinth holds the title of the world's most widespread invasive alien species on land, underscoring its significant impact on various ecosystems.