CHENNAI: In a first-of-its-kind exercise, the Tamil Nadu forest department will conduct a two-day statewide raptor assessment on January 31 and February 1 to map the distribution and relative abundance of birds of prey across diverse habitats. The survey is being carried out in collaboration with the Advanced Institute for Wildlife Conservation (AIWC) through the Tamil Nadu Raptor Research Foundation (TNRRF), which was established in July 2025.
Raptors, including kites, eagles, hawks, falcons and owls, play a key ecological role as apex predators and scavengers, helping regulate prey populations and maintain balance in ecosystems.
“The objective is long-term monitoring. Conservation success is defined by change over time, not by numbers at one point,” a senior forest official said. “This assessment will help us understand trends and link them to possible causes, which is essential for targeted conservation action.”
Chief Wildlife Warden Rakesh Kumar Dogra told TNIE that the survey would help build a scientific baseline for raptor conservation in Tamil Nadu. “Raptors are key bio-indicators of environmental health. A systematic assessment will enable us to identify priority landscapes, threats and hotspots, and strengthen long-term monitoring across ecosystems,” he said.
The survey will focus on mapping distribution across Tamil Nadu, estimating relative abundance, identifying raptor hotspots, and selecting indicator species that reflect habitat quality. Forest officials said raptors are also important from a wider ecological and public interest perspective, as a decline in these predators and scavengers could trigger changes in prey populations, disease spread, and broader impacts linked to ecosystem imbalance.
The entire state has been divided into grid blocks of roughly 32 sq km, with 4,068 blocks forming the sampling frame. Around one-tenth of the landscape is aimed to be assessed during the exercise, covering 411 blocks across the state.
AIWC Director A Udhayan said raptors exist at low densities and are often difficult to monitor. "So, the two-day protocol includes both diurnal and nocturnal raptors. The first day, January 31, will include a pre-survey training at the division level by the nodal officer, followed by the nocturnal assessment. The second day, February 1, will focus on the diurnal raptor assessment. Also, being a full moon day increases the chances of documenting nocturnal birds such as owls and nightjars," he told TNIE.
Each selected grid block will be surveyed in a single day using a combination of vehicle-based and foot-based searches. Vehicle surveys will be carried out at speeds not exceeding 20 kmph, covering over 20 km using secondary or rural roads to minimise disturbance. Foot surveys spanning over 6 km will be conducted in hotspots and in landscapes where vehicles cannot access. The nocturnal assessment will also include point count methods using a vehicle to improve detection.
Tamil Nadu hosts over 65 raptor species across forests, hillocks, agricultural fields, wetlands, coastal areas, dump yards and other hotspots. Threats such as habitat loss, poisoning, electrocution and illegal trade make long-term monitoring essential, officials said.
Species expected to be recorded include the black kite, brahminy kite, Eurasian kestrel, shikra, crested goshawk and changeable hawk-eagle, apart from key scavengers such as the Egyptian vulture. Teams will use binoculars, data sheets, mobile mapping tools and track-recording applications to ensure standardised reporting across divisions.