The Grey Warbler or Riroriro is an endemic New Zealand bird. Here are some fun facts about this tiny, common bird and tips on identifying it.
The iconic wildlife of New Zealand includes the Kiwi, Tui, Kea, and Kereru among others. Those birds are truly special in different ways. New Zealand has 171 native bird species, 93 of which are endemic, most of which aren’t well known. One of the lesser known birds is actually very widespread and common, the grey warbler. This small, inconspicuous bird just doesn’t get the same acclaim as many of the other natives.
8 Grey Warbler Facts – Riroriro
The Maori name for this endemic New Zealand bird is Riroriro. One way to know if a bird you see in NZ is native or not is whether or not it has a Maori name. It the bird has a Maori name then it’s likely been here for a long time.
The riroriro is a very small bird, with a body size of 10 – 11 cm. That is very small. Just for comparison purposes, a fantail has a body size of 16 cm, 50% bigger than this little guy! In fact, only a few birds are smaller than this one. The rifleman, considered New Zealand’s smallest bird, measures a mere 7 – 9 cm, and the rock wren is 9.5 cm.
I would be remiss if I didn’t include the most astonishing fact about this tiny bird. The grey warbler serves as a foster parent for the shining cuckoo. The sneaky shining cuckoo will put her egg into the nest of the grey warbler. Then when the eggs hatch the shining cuckoo will kick out the rest and the little grey warbler parent will raise the foster kids.
This bird’s natural habitat is the forest. It can be found most often in forest, but since people have arrived and destroyed much of the forest it has adapted. These are one of the few native birds that have benefitted from humans altering the natural landscape of NZ. The grey warbler can now be found in almost all habitats from sea level up to 1,400 meters.
Here’s another astonishing fact for you. These birds are not just small in stature, but they are super lightweight. They weigh about 6.5 grams. That’s about one third the weight of a mouse! That makes them one of the lightest birds in NZ.
These birds are mostly grey (sometimes a bit olive green) on the top, and grayish or white on the belly. Their tail has a distinctive white tip. When flying you may see the white on their tail and think for a second that it’s a fantail as the fantail also has that white tail. A difference is that this bird is much smaller than a fantail and has a shorter tail. In fact, a fantails tail (8cm) is almost as long as the riroriro (10 cm).
When trying to identify this bird you may sometimes get it confused with a rifleman. Both are very small birds that flit around the bush and may be hard to see well. A difference is that this bird clearly has a tail, while the rifleman looks like it has no tail. Also, look at the color of the eye. The riroriro has a red eye, while the rifleman has a black eye.
This bird is an insectivore, meaning that it eats insects. It will often hover in the air while eating small insects. In fact, these birds will sometimes hover above the canopy while eating insects. This is a behavior that no other bird does and makes it easy to identify them from a distance.