A decade-long study by scientists from the ICAR-Central Marine Fisheries Research Institute has revealed a dramatic ten-fold increase in whale strandings along India’s southwest coast, pointing to severe ecological stress driven by climate change and human activity.
Covering data from 2004 to 2023, the study found that annual whale stranding incidents rose from 0.3% (2003–2013) to 3% (2014–2023).
Kerala, Karnataka and Goa emerged as key hotspots, primarily due to high vessel traffic, fishing pressure and coastal shelf features.
“Region-specific conservation strategies are required to address this marine biodiversity threat in one of the country’s richest oceanic zones,” said Dr R Ratheesh Kumar, lead author of the study published in Regional Studies in Marine Science.
The research identified Bryde’s whale as the most commonly stranded species, with occasional blue whale incidents. It also confirmed the presence of two genetically distinct forms of Bryde’s whales in Indian waters.
The highest number of strandings in recent years was recorded in 2023, with nine cases, mostly between August and November. The study linked stranding events to ocean productivity during the southwest monsoon, noting a strong correlation with chlorophyll-a levels, a marker for plankton abundance. Rising sea surface temperatures and shifting ocean currents were also identified as contributing factors.
To mitigate the threat, the study is urging the creation of predictive models using satellite data and the development of real-time alerts. It also recommends training for fishers and frontline officials, alongside the strengthening of citizen science to improve monitoring.
