The Chilika Lake bird census will use fixed-wing and quadcopter transects for the first time this winter after silt buildup shifted the lagoon’s effective mouth near Satapada, leaving wader flats that survey boats cannot reach at low tide. The Odisha forest and wildlife division is not replacing boat teams; it is layering aerial counts so population estimates do not miss birds packed into channels too shallow for outboard skiffs.
What changed in the lagoon
Hydrologists at the Chilika Development Authority said the outer bar mouth that reopened after Cyclone Fani has narrowed again, pushing sediment into feeder channels where lesser flamingos and black-tailed godwits stage before the Himalayan push. Fisherfolk in Satapada reported propeller strikes on sandbars last month; census planners took that as a signal that traditional transect lines drawn in 2019 no longer match bird distribution.
BNHS-trained ornithologists still lead the count, but CDA issued a drone protocol: flights at 120 meters above ground over mudflats, no launches during active fishing net casting, and thermal imaging banned to avoid disturbing roosts. Data will be fused with boat-based point counts using distance sampling methods the Wetlands International India office reviewed.
Why drones, why now
Winter census numbers feed into Ramsar reporting and local tourism boards that promote dolphin and bird safaris. Undercounting flamingos because skiffs cannot enter a silt chute would skew trend lines just as the state pitches eco-tourism packages out of Puri and Bhubaneswar. Drones are cheaper than dredging, and the forest department already owns units for anti-poaching patrols near Nalabana sanctuary.
Regulators are watching noise and disturbance. Bombay Natural History Society advisers asked teams to keep morning flights brief and to ground quadcopters when marsh harriers are hunting—an ethical line as important as the technical one.
What fishermen see
Boat operators worry census flights will precede new no-go zones. Division officials said existing fishing rights inside the lake remain, but drone maps may inform where CDA proposes silt scooping after the count ends in January. That coupling makes the census political as well as scientific: bird numbers justify conservation spend; fishermen want proof dredging will not steal navigable channels they use during hilsa season.
After the count
Preliminary transect schedules publish in October once monsoon runoff stabilizes salinity gradients. If drone and boat totals diverge by more than ten percent on key species, reviewers will rerun overlapping grids. Tourism operators in Barkul were briefed not to fly recreational drones near census lanes; violations can cost licenses during peak season.
For Chilika, the immediate story is a place on the map responding to a moving mouth—counting birds where the water used to be deep enough for a propeller, and admitting that silt and shifting channels changed the survey before the migrants did.
