Yellowhead

The yellowhead, also known as the mohua or bush canary, is a small, insectivorous bird native to New Zealand's South Island. It belongs to the Mohouidae family, alongside its close relative, the Whitehead, which inhabits the North Island and adjacent smaller islands. Historically abundant in the beech forests of various regions, the yellowhead's population dramatically declined in the early 20th century due to the introduction of predators like black rats and mustelids. Today, they have disappeared from 75% of their former range, with about a quarter of the remaining population residing in the beech forests of the Catlins area.

As a protected and threatened endemic species in New Zealand, substantial conservation efforts are being undertaken to ensure the mohua's survival. Populations have been successfully reintroduced to predator-free offshore islands such as Breaksea Island and Ulva Island. The Department of Conservation has implemented pest control measures, including the use of biodegradable 1080 poison, to help stabilize mohua populations on the mainland. For instance, in the Dart Valley, over 80% of the mohua survived in areas with pest control, compared to just 10% in untreated areas. In the Landsborough Valley, the mohua population has quadrupled since 1998, thanks to intensive pest control, allowing for the translocation of birds to new habitats, such as Resolution Island.

Aerial 1080 operations in various valleys have not only benefited the mohua but have also contributed to the recovery of other bird species such as bellbirds and tomtits in the Catlins region. These efforts illustrate the positive impact of targeted conservation strategies in preserving New Zealand's unique wildlife.