The lake is formed by the natural depression between the Krishna and Godavari deltas.
It is a Ramsar wetland site, specifically recognized for its critical role in supporting thousands of migratory birds annually.
The Upputeru river serves as the only outlet for the lake, eventually discharging into the Bay of Bengal.
The lake's surface area can vary from nearly 900 square kilometers during peak monsoon to significantly less during dry seasons.
It hosts the Pelicanry at Atapaka, a major breeding ground for grey pelicans.
The ecosystem sustains over 60 species of fish and several endangered bird species including the glossy ibis and painted stork.
Kolleru Lake is one of the largest freshwater lakes in India, situated between the Krishna and Godavari river deltas in Andhra Pradesh. The lake is a designated Ramsar site of international importance due to its function as a vital habitat for migratory birds. It serves as a natural flood-balancing reservoir for the surrounding fertile agricultural plains. The water body fluctuates significantly in size depending on seasonal monsoons, often expanding or contracting based on drainage from inflow channels. The Atapaka Bird Sanctuary, located within this ecosystem, acts as a primary focal point for avian observation. The lake supports a diverse aquatic ecosystem, including numerous fish and crustacean species. Local livelihoods are deeply integrated with the lake's resources, particularly through traditional fishing practices. Water levels are managed through the Upputeru drain, which connects the lake to the Bay of Bengal.
The observation towers within the Atapaka Bird Sanctuary provide the most comprehensive vantage points for landscape and avian photography.
Bring high-quality binoculars as bird sightings occur at a distance from the banks.
Wear light, breathable clothing and apply insect repellent due to the wetland environment.
Hire a local boat guide to navigate the shallow waters safely and reach the prime bird-watching islets.
Visiting during the peak summer months when the water level recedes drastically, limiting boat access and reducing bird populations.
Best visited during the winter migration season; water levels and bird presence are highly seasonal and weather-dependent.
Maintain silence near bird nesting sites, avoid littering in the water, and refrain from feeding wildlife.
