The Bellanwila-Attidiya marshes cover approximately 372 hectares and were officially declared a wildlife sanctuary on 25 July 1990 under the Fauna and Flora Protection Ordinance. The sanctuary was established to protect its unique wetland ecosystem, which serves as an important breeding ground for resident birds and a seasonal refuge for migratory birds visiting Sri Lanka. Over the years, it has become one of the country's most significant urban conservation areas.
One of the most remarkable features of the Attidiya Bird Sanctuary is its interconnected wetland ecosystem. Rather than being a single marsh, the sanctuary is a network of marshes, shallow lakes, ponds, canals, paddy fields, seasonally flooded grasslands, and waterways. These habitats are naturally connected and form part of the Bolgoda River Basin, creating an ideal environment for wildlife to thrive.
The marshes and ponds provide breeding grounds for fish and amphibians, while the paddy fields and grasslands offer feeding areas for wading birds. During the rainy season, excess water flows through these wetlands, allowing the sanctuary to function as a natural flood retention area that helps reduce flooding in the surrounding suburbs. This diverse landscape is one of the reasons why Attidiya supports such a rich variety of plant and animal life.
Attidiya Bird Sanctuary is home to an impressive range of wildlife. Scientific studies have recorded over 150 species of vertebrates, including approximately 78 species of birds, 27 reptile species, 22 freshwater fish species, 11 amphibian species, 14 mammal species, and more than 75 species of butterflies. Several endemic and nationally threatened species have also been recorded within the sanctuary, highlighting its importance for biodiversity conservation.
Apart from birds, the sanctuary is home to water monitors, mongooses, porcupines, frogs, freshwater fish, dragonflies, butterflies, and numerous aquatic plants that contribute to the health of the wetland ecosystem.
Attidiya Bird Sanctuary is not only an important conservation area but also a peaceful destination for visitors. One of the best panoramic views of the wetlands can be enjoyed from the upper levels and surrounding grounds of Bellanwila Rajamaha Viharaya, where visitors can overlook the vast green marshes stretching into the distance.
Another popular way to experience the sanctuary is by walking along the Bellanwila–Boralesgamuwa walking paths and nature trails, which pass beside ponds, canals, marshes, and paddy fields. These walking routes are particularly beautiful during the early morning and late afternoon when birds are most active. The peaceful environment, cool breeze, and abundance of wildlife make the sanctuary a favourite location for birdwatchers, photographers, joggers, nature enthusiasts, and families seeking a relaxing escape from the busy city.
The sanctuary performs several essential environmental functions that benefit both wildlife and nearby communities. These include:
- Acting as a natural flood retention area by absorbing excess rainwater.
- Filtering pollutants and improving water quality.
- Providing breeding and feeding grounds for numerous species.
- Supporting resident and migratory birds.
- Helping regulate the local climate.
- Conserving biodiversity within a rapidly urbanizing region.
- Serving as an outdoor classroom for environmental education and scientific research.
- As one of the few remaining wetlands close to Colombo, Attidiya demonstrates that important wildlife habitats can survive even within highly urbanized landscapes.
