Kerala’s wetlands, a lifeline for biodiversity and livelihoods, have witnessed a slight decline of 58 hectares between 2019 and 2024, according to a new geospatial study that assessed temporal changes using multi-date satellite data.
The study, conducted by the Centre for Water Resources Development and Management (CWRDM) using Sentinel-2A MSI imagery within a Geographic Information System (GIS) framework, revealed that the total wetland area in Kerala shrunk from 1,52,826 hectares in 2019 to 1,52,768 hectares in 2024.
The study also documented the disappearance of three wetlands covering 74.78 hectares and the emergence of three new wetlands spanning 0.52 hectares, reflecting the dynamic and shifting nature of wetland boundaries under changing climatic and anthropogenic pressures.
While the overall reduction appears modest, researchers warn that localised wetland losses, especially in inland systems, could trigger serious ecological consequences, and call for more detailed study to initiate conservation.
A more focused and detailed study using advanced technology should be undertaken, said K C V Naga Kumar, scientist and head of Land and Water Management Research Group at CWRDM. “Effective land-use planning, continuous satellite-based monitoring and enforcement of conservation policies are vital to safeguard these fragile ecosystems.
Continuous monitoring is the key and similar studies should be done at regular intervals. Else in the next decade or two, there will be a drastic decline,” he said.
Inland natural wetlands accounted for 45.09% of Kerala’s total wetland area, followed by coastal natural wetlands (28.03%), inland man-made wetlands (24.38%), and coastal man-made wetlands (2.5%).
The analysis found that inland waterlogged areas shrank by 73.58 hectares, tanks and ponds declined by 11 hectares, whereas coastal natural wetlands such as mangroves and lagoons registered a small increase of 61 hectares.
“Kerala’s wetlands seem stable in total extent; rapid urbanisation, agriculture and infrastructure expansion could amplify the risk of fragmentation and degradation in coming years,” said CWRDM executive director Manoj P Samuel. Wetlands play a crucial role in flood mitigation, water purification, carbon sequestration and biodiversity conservation, making their protection essential to Kerala’s environmental health and food security.
“The apparent stability masks localised but severe losses,” the report notes. Manoj said the CWRDM jointly with the Ministry of Environments and State Wetland Authority of Kerala (SWAK) is initiating steps to conserve the wetland with community engagement. “We need to come up with conservation and management strategies for wetland conservation with the help of youngsters,” he said.