About Kanwar lake:
- It is Asia’s largest freshwater oxbow lake located in Bihar.
- It is also known as Kabartal jheel which is a rainfed lake.
- It is a residual oxbow lake, formed due to the meandering of Gandak river, a tributary of Ganga.
- It is covering the majority of the Indo-Gangetic plains in northern Bihar,
- The Wetland is an important stopover along the Central Asian Flyway, with 58 migratory waterbirds using it to rest and refuel.
- It is also a valuable site for fish biodiversity with over 50 species documented.
- Five critically endangered species inhabit the site, including three vultures – the red-headed vulture (Sarcogyps calvus), white-rumped vulture (Gyps bengalensis) and Indian vulture (Gyps indicus) – and two waterbirds, the sociable lapwing (Vanellus gregarius) and Baer’s pochard (Aythya baeri).
- Threats: Major threats to the site include water management activities such as drainage, water abstraction, damming and canalization.
What is an oxbow lake?
- It is a curved lake formed alongside a winding river as a result of erosion and sediment deposition over time.
- Oxbow lakes are typically crescent-shaped and are common features in floodplains and low-lying areas near rivers.
Q1: What is the Central Asian Flyway?
The Central Asian Flyway (CAF) covers a large continental area of Eurasia between the Arctic and Indian Oceans and the associated island chains. The Flyway comprises several important migration routes of water birds, most of which extend from the northernmost breeding grounds in the Russian Federation (Siberia) to the southernmost non-breeding (wintering) grounds in West and South Asia and other regions.
Last updated on November, 2025
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