Bird count shows a marginal decline in migratory waterfowls wintering in Punchakari-Vellayani

The annual waterbird census was conducted in January

Black Winged Stilts, migratory waders, at Punchakari in Thiruvananthapuram | Photo Credit: C Susanth Kumar

As temperatures plummet in the Arctic, a brownish bird, weighing around 400 grams, begins a non-stop flight from its home in frozen north-west Siberia to winter in certain Indian states. Flying more than 11,000 kilometres in nine days, the birds flies non-stop till they reach their destinations along the Indian coastline.

Known as the Bar-tailed Godwit ((Limosa lapponica), this long-distance flier can be seen in the Punchakari-Vellayani area, in the suburbs of Thiruvananthapuram, during the months of December and January, one of the many species of migratory birds that winter in Kerala.

Oyster catcher, a migrant wader from Eurasia, at Vellaanathuruthu beach near Kollam | Photo Credit: C Susanth Kumar

C Susanth Kumar, coordinator of Thiruvananthapuram-based Warblers and Waders, a group of naturalists and birders, says the Black-winged stilts, Perching Lesser Crested Terns (common tern species), Wood Sandpiper, Woodcock, Painted Storks, Glossy Ibis and Sand Plovers are some of the visitors that reach the shores of Kerala every year.  

Even before the sun is up, birders flock to the wetlands in and around the city to spot these visitors that thrive in marshy spots, estuaries, beaches, waterbodies and paddy fields in and around Punchakari-Vellayani, Veli, Aakulam, Poovar and St Andrews Beach.

Perching Lesser Crested Terns at Azheekal beach, near Kollam | Photo Credit: C Susanth Kumar

A count of the migratory birds and residents has been taken every year since 1987, invariably in the month of January, by birders in association with World Wildlife Fund and volunteer groups. The Asian Waterbird census is part of the global International Waterbird census, which supports the conservation and management of wetlands and waterbirds.

For 33 years, members of Warblers and Waders have been part of the census in Thiruvananthapuram and Kollam. In January, 23 volunteers, including college students and bird experts of Warblers and Waders participated in the survey led by experts such as Susanth, S Rajeevan, R Jayaprakash, K A Kishore, Dr Blessan Santhosh George, Dr M K Krishnakumar and G Santhosh Kumar.

Bar-tailed Godwit | Photo Credit: C Susanth Kumar

“In Thiruvananthapuram, the waterbird survey was taken at Punchakari-Vellayani wetlands, Akkulam lake and Veli-Perumathura shore, says Susanth. “In Kollam, the survey was conducted at Pollachira wetlands near Chathanoor, Vellaanathuruthu beach and Azheekkal Beach near Karunagapally.”

During the survey in these areas, a decrease in the number of Bar-tailed Godwits was noticed in the areas in Thiruvananthapuram. 

Documenting some winter visitors

       Perching Lesser Crested Terns visit coastal areas of Kerala during the migratory season. Large flocks of Lesser and Large Crested Terns were observed at Azheekal Beach.

 Lesser Sand Plovers, Temmnick Stints, Grey-Headed Lapwing, Painted Snipe and Little Ringed Plovers are usually found in the Punchakkari wetlands.

Mixed flocks of Black-headed and Brown-headed gulls at the sea shore of Vellanathurthu are a common sight during this period. In 2022 and 2023, however, the presence of this bird on the Thiruvananthapuram shore was quite low.

Black-winged stilts, a migratory bird from the Gulf countries in Asia, has a small population that breeds in Ladakh and adjacent places, says Sushanth. “The presence of this migratory bird in Punchakkari wetlands has shown a decline this year. Wood Sandpiper, Woodcock, Painted Storks and Glossy ibis, however, were more this year.”

Mixed flock of brown-headed and black-headed gulls | Photo Credit: C Susanth Kumar

Susanth, also coordinator of the water bird census, says they found significant changes in the number of birds visiting the wetlands in and around the two districts. “Last year, we counted 4,800-plus birds and 61 species of waterbirds.  The changes in bird population and numbers were more evident in Thiruvananthapuram compared to Kollam, especially in Veli and the Punchkari-Vellayani wetlands. Some of these birds seem to have moved to Poovar and Kadinamkulam.”

He says the drop in number of birds and species in Punchakari-Velayani was noticed in 2022 as well and the reason will have to studied in depth before arriving at a conclusion. “One reason might be the rise in human activity in these regions. Till a few years ago, there were places around Veli and Vellayani that were quiet and relatively free of people. Another reason might be pollution and change in food availability.”

For instance, in Kollam,  Vellaanathuruthu beach and Azheekkal Beach have plenty of oysters and fish that are eaten by waterfowls. Human activity has not increased perceptibly in these areas and, as result, the bird count has not registered a major change.