Chroicocephalus novaehollandiae, commonly known as the Silver Gull, is native to Australia. It is widespread across the continent, inhabiting coastal areas, inland waters, and urban environments. The species is also found in Tasmania, New Zealand, and New Caledonia.

The Silver Gull thrives in a variety of habitats, predominantly coastal regions such as beaches, estuaries, and mudflats. It is also commonly seen around inland bodies of water, including lakes, rivers, and reservoirs. In urban settings, it adapts to environments such as parks, garbage dumps, and fishing harbors. The species is highly adaptable and can tolerate a broad range of environmental conditions.

Silver Gulls are opportunistic feeders and play a vital role in their ecosystems as scavengers and predators. They feed on fish, insects, crustaceans, and human food waste, which can help control pest populations and clean up organic debris. Their adaptable nature and wide dietary range allow them to thrive in diverse habitats, from natural coastal areas to human-modified environments.