Eichhornia Invasion

Eichhornia invasion is the spread of water hyacinth (Eichhornia crassipes, now placed in Pontederia), a free-floating freshwater macrophyte native to South America that colonizes lagoons, estuaries, and brackish coastal waterways. Dense floating mats double in area within weeks, blocking light, depleting dissolved oxygen as biomass decays, obstructing navigation, and clogging intakes. Tolerant of low salinity, it invades the upper, freshwater-influenced reaches of coastal lagoons and deltas, displacing native vegetation and altering fish habitat. It ranks among the world’s most damaging aquatic invasive plants on the IUCN list, with control relying on mechanical removal, biocontrol weevils, and nutrient-load reduction.