The unusual early departure of migratory birds from the Chilika Lake and Bhitarkanika National Park in Odisha has sparked concerns. The change was observed in February, significantly earlier than the usual migration period of mid-March to early April. This departure coincides with soaring temperatures around the freshwater bodies in this region.
Migratory Species and their Habitats
Typically, the onset of winter brings a host of migratory birds to the region surrounding Chilika Lake and Bhitarkanika National Park. These aviary visitors hail from far-off places such as Siberia, Afghanistan, Iran, Iraq, central Europe, and the Himalayan region. Chilika Lake, the largest salt-water lagoon in Asia, and Bhitarkanika, India’s second-largest mangrove forest, serve as their primary habitats.
Factors Influencing Early Departure
Two primary factors have emerged as probable reasons for this surprising early migration. For one, the average temperature of the region, particularly in Bhubaneswar, which is around 35 kilometers from Chilika, has been steadily rising. February temperatures from 2015 to 2019 have consistently hovered around 34-35 degrees Celsius. The second factor is the decreasing water levels in the lake, possibly due to increased evaporation caused by higher temperatures.
Chilika Lake: A Biological Treasure Trove
The Chilika Lake holds the distinction of being both Asia’s largest and the world’s second-largest lagoon. Moreover, it’s the most preferred destination for migratory birds on the Indian sub-continent during winter. The lake also hosts several threatened species of plants and animals. In 1981, the Ramsar Convention marked Chilika Lake as the first Indian wetland of international importance. The lagoon is famous for Irrawaddy dolphins, especially near Satpada Island, and the Nalabana Island bird sanctuary. Another major attraction is the Kalijai Temple located on an island in the lake.
Bhitarkanika National Park: A Hub for Biodiversity
Bhitarkanika National Park stands as one of Odisha’s key biodiversity hotspots. The park is known for its mangroves, migratory birds, turtles, estuarine crocodiles, and numerous creeks. Practically a mosaic of different ecological sites, it consists of the Bhitarkanika National Park, the Bhitarkanika Wildlife Sanctuary and the Gahirmatha Marine Sanctuary. Bhitarkanika is located amid several river systems including Brahmani, Baitarani, Dhamra, and Mahanadi. It is home to around 70% of India’s estuarine or saltwater crocodiles, whose conservation initiative began back in 1975.
Migratory Species in India and Conservation Efforts
India serves as a temporary abode to many migratory species, from Amur Falcons and Bar-headed Geese to Humpback Whales and Dugongs. It forms a crucial part of the Central Asian Flyway (CAF), covering areas between the Arctic and Indian Oceans. To conserve these migratory species, India has initiated the National Action Plan under the Convention on Migratory Species (CMS), of which it is a member.
