This stout little rifleman is New Zealand’s smallest bird

This New Zealand wren is just adorable.
Contributor

Bec Crew

Contributor

Bec Crew

Becky Crew is a Sydney-based science communicator with a love for weird and wonderful animals. From strange behaviours and special adaptations to newly discovered species and the researchers who find them, her topics celebrate how alien yet relatable so many of the creatures that live amongst us can be.

By Bec Crew June 22, 2020 Reading Time: 2 Minutes

THERE ARE MANY small birds, so to be the smallest, you have to be pretty darn tiny. At roughly 8 cm long and weighing a mere 6 grams, the rifleman is pretty darn tiny.

Endemic to the high-altitude forests of the North and South Islands of New Zealand, the rifleman (Acanthisitta chloris) is the country’s smallest native bird. To give you an idea of just how minute this species is, a house sparrow is 16 cm long, and can weigh up to 40 grams.

Related: The bird that weighs the same as a teaspoon of sugar

The rifleman belongs to the Acanthisittidae family of New Zealand ‘wrens’, along with just one other species, the New Zealand rock wren (Xenicus gilviventris), a plucky little bird that is almost tailless, found only in the alpine regions of the South Island.

We say ‘wrens’, because, despite looking just like a wren, neither species are actually wrens. In fact, they’re not related at all to the true wrens family (Troglodytidae), or the fairy-wrens of Australia.

Both the rifleman and the New Zealand rock wren are built to blend into their surroundings. In both species, the male has bright green plumage, while the female has a more dull, brown hue.

Here’s a picture of a male rifleman, which shows just how tiny they are:

(Image credit: New Zealand Department of Conservation)

And it’s lucky they can camouflage so well. Like the adorable kakapo (New Zealand’s hefty night parrot), the iconic kiwi, and the rest of these strange, flightless birds, the rifleman and the New Zealand rock wren are terrible fliers. They’re not as completely ground-bound as the kakapo and kiwi, but they’re only able to cover very short distances.

It’s ironic that such a lightweight bird finds it tough to stay airborne. It’s also very rare for a passerine bird (also known as songbirds) to not be a strong flyer. It likely has to do with the fact that, for millions of years, the ancestors of these birds lived without the threat of mammals, such as possums and rats.

The good news is the rifleman’s population remains healthy, although it is in decline due to a loss of habitat. The bad news is the New Zealand rock wren is classified as endangered, owing, in a large part, to predation from mice and stouts.

The rifleman’s tough name doesn’t exactly suit its sweet exterior. It refers to the bird’s resemblance to the uniform of an early colonial regiment, which would have looked something like this. It’s also known as Tītipounamu, a Māori word that can be loosely translated to mean “mirage of greenstone”, a type of rock found in New Zealand.

We’ll leave you with some footage of the rifleman in action on Tiritiri Matangi Island, a wildlife sanctuary on the North Island: