A rapid spread of pink waterlilies in Kerala’s Kuttanad paddy fields has created a new tourism wave and fresh sources of income for farming communities. But scientists warn that this sudden boom may be hiding long term ecological risks that could harm biodiversity and reduce paddy sustainability.
Kuttanad covers 55,000 hectares across Alappuzha, Kottayam and Pathanamthitta districts, and is India’s lowest farming area, lying one to two metres below sea level. It forms part of the Vembanad Kole Ramsar wetland and is globally recognised by the United Nations Food and Agriculture Organization for its unique below sea level farming system. Since the 2018 floods, a hybrid waterlily species, Nymphaea omarana, has rapidly colonised fallow paddy fields, especially in Malarikkal, turning them into seasonal pink lakes that attract visitors from June to October.
Local families now run boat services, serve food and sell waterlily plants to tourists. Researchers funded by the Kerala State Council for Science Technology and Environment say a single farmer can earn one to two lakh rupees in just three months, and overall seasonal tourism income can reach two hundred lakh rupees in a year. Local bodies are using the tourism push to improve roads and obtain development funding.
However, the benefits come with hidden costs. Waterlily is listed as an introduced invasive species. Its rapid growth has been linked to reduced saline water inflow, especially due to prolonged closure of the Thanneermukkam barrier, which has altered the natural balance between salt and fresh water that once controlled weed spread. Waterlily growth improves soil organic content and helps remove heavy metals, but it also blocks sunlight, slows water flow, reduces fish habitat and increases methane emissions when large biomass decays.
Farmers are now dependent on repeated herbicide use to control waterlily expansion. Earlier, broad spectrum chemicals were applied to mixed weeds, but now selective herbicides are used to target waterlily, often followed by additional treatments if sedges and broad leaf weeds appear. Mechanical removal is possible but time consuming and costly. Seeds of waterlily survive in underwater sediments, making long term control difficult.
The invasion has altered wildlife patterns. Populations of turtles, wetland birds and rodents are rising as they feed on flowers, buds and seeds. Fishermen are reporting lower catches due to reduced water quality. Scientists have observed insect pests that damage waterlily plants, but their future effect on rice crops is still unknown.
Experts suggest a mix of strategies including mechanical removal, biological control using pests that naturally damage waterlilies and controlled saline water flow when the Thanneermukkam barrage opens each summer. They warn that replacing paddy with waterlily for year round tourism would damage Kerala’s food security. They call for joint action by farmers, ecologists, local bodies and agriculture scientists to create a management plan that supports tourism while protecting the wetland ecosystem.
Researchers say any temporary income benefits must not distract from the long term decline in soil health, fish habitats and agricultural productivity. Without intervention, the cost of unchecked spread of Nymphaea omarana will be higher than the money it brings, affecting both ecology and livelihoods in the coming years.