Grey Gerygone

The Grey Warbler, known in Māori as the Riroriro and scientifically as Gerygone igata, is a diminutive bird endemic to New Zealand. It is one of the smallest birds in the region, measuring approximately 11 centimetres in length and weighing up to 6.5 grams. The plumage is a subtle grey-brown with an olive-green hue, while the face, throat, and breast are a lighter grey. The abdomen is off-white with a yellowish tinge. In flight, one can observe the white underparts of the tail contrasted with the dark brown top and white tips. A distinctive ruby-red eye sets this bird apart, with females being slightly smaller than males but similar in appearance. Juveniles are paler with brown eyes and lack the yellowish abdomen.

Identification Tips

When trying to identify the Grey Warbler, look for its small size, grey-brown plumage with a slight olive tint, and the characteristic red eyes. The pale grey underparts and the white-tipped tail are also key features. Females and males are similar, but the former are marginally smaller.

Habitat

The Grey Warbler thrives in temperate forests across New Zealand. It is adaptable and can be found in both native and exotic forested areas, as long as there is sufficient tree or shrub cover.

Distribution

This species is widespread throughout New Zealand's main islands and many offshore islands, though it avoids open country and alpine regions.

Behaviour

The Grey Warbler is a highly active bird, rarely staying still as it flits from perch to perch. It is often heard before it is seen, thanks to its distinctive song.

Song & Calls

The male Grey Warbler's song is a notable feature, beginning with three squeaks and escalating into a long, plaintive, wavering trill that fluctuates in pitch. The song is a year-round performance, peaking in the spring nesting season.

Breeding

Breeding season for the Grey Warbler spans from August to January, with the potential for two clutches. The species constructs a unique pear-shaped nest with a side entrance, woven from grass, leaves, rootlets, and moss, and bound with spider silk. Nests are placed 2 to 25 feet above ground and lined with soft materials like feathers. While males gather nesting materials, only females build the nest. The male does not incubate but assists in feeding the young. Clutches typically contain 3 to 6 pinkish-white eggs speckled with reddish-brown, each laid two days apart. Incubation lasts about 19 days, with chicks remaining in the nest for another 15 to 19 days. The second clutch is often parasitized by the Shining Bronze Cuckoo.

Diet and Feeding

The diet of the Grey Warbler consists mainly of spiders, insects, and their larvae.

Conservation status

The Grey Warbler is classified as Least Concern by the IUCN, indicating a stable population without significant threats at present.