Gazumbo Island was formed in the 1980s during the construction of the bridge, which caused dredged materials to accumulate and create two islets.

[1] Gazumbo Island features a topography characterised by beaches and mudflats, with a low-lying depression at its centre that fills during high tide.

[1] The islet supports a diverse ecosystem, including various species of seagrass, mangroves, and terrestrial plants such as casuarina, wild jasmine and sea almond.

[1] To safeguard the surrounding ecosystem, the Penang state government has proposed designating approximately 10 km2 (3.9 sq mi) of the Penang Strait as a marine protected area.

However, as of 2024[update], this proposal was put on hold pending development associated with the nearby Jelutong landfill.