Gray Gerygone

The grey warbler, also known by its Māori name riroriro or outside New Zealand as the grey gerygone, is an insectivorous bird in the family Acanthizidae endemic to New Zealand. It is sometimes known as the rainbird. Its natural habitat is forests, but also tends to occupy lower vegetation habitats. These insectivorous birds feed on insects living in shrubs, and often feed on the wing. They are found throughout New Zealand, as well as offshore islands where shrub exists. They also flourish in suburban areas where there is vegetation present.

Source: Wikipedia