Kuljak Island, also known as Black Swan Island, is an artificial island in the Swan River. Situated between Ron Courtney Island upstream and Heirisson Island downstream, Kuljak Island is east of Maylands Peninsula and south of Garratt Road Bridge. Kuljak Island is surrounded by a number of smaller, also artificial, islets, and is entirely within the boundaries of the suburb of Ascot.

The Swan River is a major river in the southwest of Western Australia. The river runs through the metropolitan area of Perth, Western Australia's capital and largest city.