Prosthemadera novaeseelandiae, commonly known as the Tui, is native to New Zealand. Its geographical distribution includes the North, South, and Stewart Islands of New Zealand. It is also found on many offshore islands, such as the Chatham Islands and the Great Barrier Island.

The Tui typically inhabits a range of environments from coastal areas to forests. Its preferred habitats include native forests, mixed podocarp-broadleaf forests, and regenerating bush. Tuis have also adapted to suburban and urban gardens with abundant native and exotic flowering plants.

Tuis play an important role as pollinators in their ecosystem. They feed primarily on nectar from various native plants, such as kowhai, flax, and pohutukawa. They have a specialized brush-tipped tongue to extract nectar. In addition, Tuis consume fruits, insects, and occasionally small invertebrates. Their presence is vital for the pollination of many endemic plant species, influencing the biodiversity of their habitat.