Invasive Alien Species (IAS)

Invasive Alien Species (IAS): Recently, as global trade adapts to new bilateral agreements and changing tariffs, a growing concern has emerged: the rising spread of Invasive Alien Species (IAS).

o A new analysis warns that these biological intrusions, often unintentionally introduced via trade routes, pose significant risks to biodiversity, food security, public health, and economic stability.

• Key Highlights: The giant African snail, introduced in colonial Calcutta (c. 1847), is one of India’s earliest and most damaging IAS cases.

o Deliberate introductions (e.g., cane toads in Australia, mosquitofish and guppies in India) for biocontrol have often backfired.

o Biofouling during maritime trade allows aquatic species like the Asian paddle crab to travel undetected.

o India's import of PL 480 wheat (1955) introduced Parthenium, a toxic invasive plant now found nationwide.

o Introduction of Tilapia for food security displaced native freshwater species in Indian rivers.

• About IAS: These species are not native and are introduced through human activities such as agriculture, aquaculture, pet trade, or transport (like ballast water).

o Key Characteristics They reproduce rapidly, enabling them to spread quickly and dominate new habitats.

ü They often thrive due to the absence of natural predators or competitors in the introduced environment.

ü Their broad environmental tolerance allows them to survive in extreme or varied climatic conditions.

ü They can disrupt ecosystem functions by altering processes like nutrient cycling, fire patterns, and habitat structure.