New Zealand’s Smallest Endemic Bird isn’t a True Wren, it’s the Rifleman

Despite being known as one of the New Zealand wrens, of which it is one of only two surviving species, the Rifleman actually belongs to the ancient Acanthisittidae family. They are often called “wrens” due to similarities in appearance and behaviour to the true wrens of the family Troglodytidae.

Rifleman high
A female rifleman high in the beech canopy

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The family is represented by only six known species of which four are now extinct. Of the extinct species, most of them were believed to be flightless. This makes them the only species in the order Passeriformes (perching birds) known to have been flightless. The two remaining species (rifleman and rockwren) are categorised into different genera.

The New Zealand wrens evolved in the absence of mammals for many millions of years. Over this time, the family began to lose their ability to fly as they were now living with reduced selection pressure from predators. With the arrival of humans and the following introduction of mammalian pests (both deliberate and accidental), habitat destruction and modification, these poorly flighted and flightless birds either become extinct or had their populations greatly reduced. Nowadays, the rock wren is widely but patchily distributed through alpine and sub-alpine areas of the South Island, and is currently considered to be endangered. And as for the rifleman, despite being locally common, their populations are described as ‘in decline’ according to IUCN’s Red List.

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Riflemen are insectivores that call native forest home. They are constantly on the move, furiously flutter from branch to branch through the canopy, and hop up and down tree trunks while foraging. The birds are tiny, weighing as little as 6g (the equivalent of 6 smarties!). They are round with rounded wings, a stumpy tail and slightly upturned bills. Rifleman characteristically flick their wings as they dart about the forest.

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Rifleman are sexually dimorphic with males being smaller than females, and having bright green/yellow plumage. Females are brown and yellow and look more drab in comparison to the males. The birds make a high-pitched buzzing call that is at a very high frequency. Some people are unable to hear the call because of this, especially as they get older.

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The story behind these images goes as follows. On an awfully damp Easter weekend camping trip to Whakapapa in the Tongariro National Park, we stumbled upon a high-pitched, rapid ‘zzzpt zzzpt zzzpt’ from the moss and lichen covered foliage surrounding us. Emma instantly said, ‘Was that a rifleman?’

We then proceeded to walk a two-hour return track in the pouring rain stopping every five minutes and scanning the bush for this tiniest of birds. Five hours later and soaked through we were back at the campsite and, would you believe it, Emma spotted two rifleman next to the caravan foraging in the trees. I tried my best to photograph the birds but, due to their size, frenzied short leaps, flaps, twitches and lack of light in the torrential downpour, my images were blurry, grainy flecks of green.

Back in the caravan, and feeling a little dejected after missing my seemingly only opportunity, we put the kettle on. With the temperature difference and moisture in the barrel of the lens, my camera lens also steamed up.

Through the toilet window of the caravan I could see the birds were back. I ran to the window, opened it, and put my eye to the viewfinder. I couldn’t see a thing. It was still fogged up! The rifleman was spinning up and down the tree in front of me, made a sudden change in direction and landed only a meter or so from the window on the ground and looked at me. Typical.

unnamed
Frustration had set in

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An hour later, camera defogged and ready to go again, I went on the search. Would you believe it, my luck was in, the birds were back hopping from tree to tree along the bank of the river. I counted four or five individuals. Third time round was a success. The photos you see here are the best of several hundred taken in about 2 minutes.

Rifleman flight
A male rifleman about to leap from his perch

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In Māori the bird’s name is tītipounamu.  ‘Tīti’ means to squeak or to make a sharp, barely audible sound. And ‘pounamu’ is a variety of jade or greenstone. So the name tītipounamu is pretty well fitted. These birds are pleasure to watch and photograph if you are lucky enough to stumble upon them. I hope that with a goal of a predator-free New Zealand by 2050, we will be seeing more of these fabulous tennis balls with beaks.

Rifleman
The best image of the weekend – Male rifleman (Acanthisitta chloris)

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References and Further Reading

IUCN Red List –  http://www.iucnredlist.org/details/22698577/0  (Retrieved 18 April, 2017)

IUCN Red List – http://www.iucnredlist.org/details/full/22698585/0 (Retrieved 21 April, 2017)

Nzbirds website – http://www.nzbirds.com/birds/titipounamu.html (Retrieved 17 April, 2017)

Nzbirdsonline website – http://www.nzbirdsonline.org.nz/species/rifleman (Retrieved 17 April, 2017)

Nzbirdsonline website – http://www.nzbirdsonline.org.nz/species/rock-wren (Retrieved 21 April, 2017)

Wikipedia – https://en.wikipedia.org/wiki/Rifleman_(bird) (Retrieved 17 April, 2017)

Wikipedia – https://en.wikipedia.org/wiki/New_Zealand_wren (Retrieved 17 April, 2017)

7 Comments Add yours

  1. Kathy Miller says:

    We visited NZ for 5 weeks (just returned home, US) and I was thrilled to see Rifleman in two spots, Arthur’s Pass Village, and Lewis Pass at Deer Valley campground. My best spotting was in our campsite at Deer Valley, when we first arrived. Loved your story, and I can certainly imagine the rain. Fond memories.

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  2. Hi Kathy,
    Thanks for reading :).
    We’re excited to hear that you were also able to see some Rifleman! They’re such precious, wee birds.
    Was this your first visit to New Zealand? Were you able to see any other cool species? We hope you didn’t have to endure too much rain, haha!
    All the best,
    Emma and Tom

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  3. A beautiful little bird, and it makes me sad to think that their numbers are in decline – that eventually they may disappear. I didn’t know that New Zealand lacked mammals for much of its history. That would create a really unique ecosystem. How fascinating. Beautiful photos. 😀

    Liked by 1 person

    1. Thank you for your comments! We’re glad you enjoyed the photos. 🙂

      Yes, you are right! The evolutionary history of New Zealand species is very interesting because of the lack of mammals. Many of our birds and insects became flightless, filling the niches that were traditionally filled by mammals. One of NZ’s most famous (extant) examples is the kiwi!

      Liked by 1 person

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