Bundala National Park is extremely popular with both local and migratory birds. About 167 bird species have been recorded in this National Park. The lagoons, enclosed within the Bundala National Park support, during some part of the year, very important populations of every species of water bird resident in the country. The lagoons also constitute one of the most important wintering areas for migratory shorebirds in the country, accommodating over 20,000 shorebirds at any time, including rare species such as the Black Necked Stork. The Park is the last refuge of the Grater Flamingo in this part of the island, up to 2,000 of these birds having been recorded during November – January.

Beside the bird life, the lagoons support a large number of fish and prawns. The reptile fauna of Bundala National Park includes many IUCN Red List species such as estuarine crocodile (mugger). At least three species of endangered marine turtles, Olive Ridley, Green Turtle, Leatherback and one vulnerable species, the Loggerhead, nest on the beach. An endemic frog (Bufo atukoralei) also has been recorded form the Park.

Bundala National Park is the foremost bird sanctuary in Sri Lanka (formerly Ceylon), located on the southern coast between the Hambantota and Kirindi rivers. The park covers 24 square miles, but despite its small size its lagoons reportedly contain every species of water bird in Sri Lanka. The five enclosed shallow and brackish water lagoons are the most important features in Bundala, though water covers only one-third of the park.

Other areas are made up of natural forest, scrub, grassland and developed land like homesteads and rice paddy fields. About 149 bird species have been recorded at Bundala, most of which are wintering waterfowl. The Bundala lagoons also constitute one of the most important wintering areas for shorebirds, sheltering up to 20,000 birds at any time, including the rare black-necked stork. The park is also the last refuge of the greater flamingo in the south of the country.

The park has an elephant population of about 30, in addition to about 50 others who migrate to the park during the dry season. Some of the other mammals in the park include leopard, sloth bear, giant squirrel, civet cat, jungle cat and fishing cat. Every year between October and January, Bundala's coastline host nesting endangered olive Ridley, green, leatherback and loggerhead turtles, four of five marine turtle species known to nest on the beaches of Sri Lanka. The park is 162 miles from the capital at Colombo, and is located off the main Colombo-Kataragama highway. Roads inside the park are for four-wheel-drive vehicles only.