Kerala Bird Atlas 2.0 Returns to Old Grids to Track a Decade of Change

Birdwatchers across Kerala are back in the field for a second statewide bird atlas, a citizen-science effort that will revisit the same survey grids mapped for the first edition released in 2021.

The original atlas, among the earliest of its kind in the country, divided Kerala's 38,863 square kilometres into 4,324 sub-cells, each surveyed by volunteers. The second iteration returns to those exact cells, a design meant to show precisely what has changed over roughly a decade.

"Birds are indicators of climate change, as modification of their habitat can tell us about changes in climate and ecology," said P.O. Nameer, dean of the College of Climate Change and Environmental Science at Kerala Agricultural University, Thrissur, and a State coordinator of the project.

He pointed to the peafowl as an example. The species belongs to dry, open country and has no historical presence in Kerala's humid, densely vegetated landscape. British-era documentation from the 1800s to the early 1900s in Travancore and Kochi does not record it, and ornithologist Salim Ali's surveys in the 1930s likewise left it out of much of the State. Its subsequent spread, Nameer said, suggests Kerala is turning from a wet, dense zone into drier open country. Several species endemic to the State, meanwhile, have been declining.

The atlas follows a standardised protocol so that data from both editions can be compared directly. Volunteers file four 15-minute checklists per site, covering the dry season from January to March and the wet season from July to September, with surveys conducted between 6.30 a.m. and 8.30 a.m. and again from 4.30 p.m. to 6.30 p.m. Observations are uploaded to eBird, and some volunteers use the Merlin app to identify bird calls.

Praveen J, a State coordinator of the first atlas who helped design its methodology, said the protocol was deliberately built to avoid the complex statistical models that semi-structured citizen-science data usually demand. "We developed a standardised protocol so that data from the first and second iterations can be directly compared, reducing the uncertainty in our conclusions," said Praveen, a former IT professional now with the Nature Conservation Foundation in Bengaluru.

Beyond bird counts, volunteers also note habitat features such as water bodies, fruiting fig trees and invasive plants. Veteran birder Jayadev Menon, a Kochi-based business coach, said this gives a fuller picture of each site. The grid system, he added, covers plains, foothills, riverine, pelagic, urban, suburban, forest and mountainous terrain. Jayadev, who has taken part in several surveys including Wetland International's annual mid-winter waterbird census, marked a personal milestone on July 28 this year: ten years of daily reporting on eBird, amounting to 24,000 checklists and more than 6,000 hours of birding, with over 505 species recorded in India.

In Wayanad, the project has doubled as community building. Rathish RL, assistant professor at Kerala Veterinary and Animal Sciences University and a State coordinator for the second atlas, said a wide network of birders has taken shape there over the past decade in a region where 15 to 20 species can be spotted at a given time. Students, homemakers, professionals and retired citizens are among the volunteers.

For younger participants, the exercise has been instructive. Nandita Raghunath, a second-year B.Sc Zoology student at St. Teresa's College, Kochi, said she learned that drongos mimic cats and other animals to trick them out of food or scare off competitors. Navaneeth Sini George, a first-year M.Sc Zoology student at Kerala University, Karyavattom, said the uniform grids remove the tendency to visit only well-known birding spots, opening up urban, rural and semi-rural areas; the campus itself served as a sub-cell, and his surveys took him to the Poovar region and the Kanyakumari border.

The second atlas is expected to be completed in three years, after which it is set to rank among Asia's largest repeat atlases.