Martinborough’s cave of bones: How thousands of flightless birds met their end

Fossilised bird grave sites are common in New Zealand, but one particular cave in Martinborough has revealed thousands of bones of flightless birds who plunged to their deaths.

Curator of vertebrates Alan Tennyson describes how over thousands of years rare and extinct birds such kakapo, kiwi, North Island takahe, and moa fell through the concealed entrance.

Alan says “It might not look like a spectacular cave but this site has become the richest site in the whole of New Zealand for some species including the nearly one metre tall extinct adzebill.”

Extinct adzebill skulls

Extinct adzebill skulls. Photo by Rachael Hockridge. Te Papa

Alan holds an adzebill skull next to a painting of the extinct bird on his book ‘Extinct Birds of New Zealand’

Curator Alan Tennyson holds an adzebill skull next to a painting of the extinct bird on his book ‘Extinct Birds of New Zealand’, published 2007. Te Papa

For over 100 years, enthusiasts and scientists have collected perhaps 1,000 individual birds and reptiles from this cave, known scientifically as a pitfall trap, which are now in Te Papa’s collections.

There are so many specimens that only around half have been registered and thousands still lie untouched in the dark cave.

Alan holds over 20 fossilised kakapo beaks

Alan holds over 20 fossilised kakapo beaks. Photo by Rachael Hockridge. Te Papa

Martinborough 1,000 years ago

Thousands of years ago the Martinborough area wasn’t the heavily farmed vineyard landscape we know today. It was covered in thick forest perfect for ground dwelling flightless birds and reptiles to roam.

Much of the land near Martinborough is underlain by limestone and this rocky landscape creates many hidden holes. The thick vegetation at the time would have concealed these and our flightless birds had very little chance of making it out alive once they fell in.

Entrance to the cave

The entrance to the cave, 2017. Photo by Alan Tennyson. Te Papa

Excavating the pit

The pitfall trap was first found by a deer hunter in 1914. Since then, Te Papa and its forerunner the Dominion Museum, have mounted several expeditions to the cave, excavating several tonnes of earth and bones.

The first expedition took place in 1920, and the most recent expedition in March 2017 included our vertebrate curator Alan Tennyson.

Specimens collected by the museum in 1920

Alan points to the box holding the first specimens collected by the museum from the cave. Photo by Rachael Hockridge. Te Papa

 A bag of uncatalogued fossil bones excavated

Alan holds a bag of uncatalogued fossil bones excavated from the Martinborough cave. Photo by Rachael Hockridge. Te Papa

In the cave

Collecting samples from the cave, 2017. Te Papa

Samples - bones and dirt

The samples Alan came back from his expedition with. Photo by Rachael Hockridge. Te Papa

The bones Alan collected haven’t been cleaned yet but Alan could identify straight away the beak of kakapo, Finsch’s ducks leg bones, and even a tuatara jaw:

Fossilised tuatara jaw

Fossilised tuatara jaw bone. Photo by Rachael Hockridge. Te Papa

Cataloguing tons of bones

Alan explains that scientists work out how many of a species there are based on the minimum number of a particular bone. “For example the strong limb bones preserve much better than a sternum or a skull. So to work out the minimum number of birds you count the minimum number of femora or tibiotarsi.”

Alan with the many boxes containing material from the Martinborough cave.

Alan with the many boxes containing material from the Martinborough cave. Photo by Rachael Hockridge. Te Papa

Because of the huge amount of material collected only about half of the bones have been sorted into individual specimens. So far, among the larger birds, 80 kakapo, 7 North Island takahe, 25 moa, 30 kiwi, 90 Finsch’s duck, 11 weka and 22 adzebills have been identified.

The sheer number of specimens identified from the cave give a good idea of how common birds such as the kakapo and adzebills were in the Martinborough region.

Kakapo remains

Kakapo remains. Photo by Rachael Hockridge. Te Papa

What’s next?

Alan believes the best thing to do with the cave now is to leave it. “Time and energy needs to be spent cleaning, sorting, identifying, and registering the huge backlog of material that we already have, and leaving the material in the cave still protects it.”

“In the future better technology might come along that helps us do a more systematic excavation and allows us to know how deep the pit goes.”

With thanks to

We’d like to thank Luke and Clint Easton who’ve generously donated many fossils from the Martinborough cave over the recent years and organised Alan’s expedition to the cave in March 2017.

18 Responses

  1. Stuart

    Fascinating 🙂

    Reply
  2. Bryan Whitfield

    Very interesting.

    Reply
  3. Tony Fleming

    Likewise, my uncle, who along with my mother, grew up in Featherstone, took us to a cave somewhere on the way to Martinborough or Lake Wairarapa in the 1970’s I think. It was a horizontal one I recall.

    Reply
  4. Ian Payton

    From the look of the sinkhole I suspect this is what we knew as Harrison’s Hole. The late RK Dell, who was at one stage the Director of Dominion Museum, described a subfossil snail (Rhytida yaldwyni) from this site. It was later shown to be a subfossil Wainuia urnula, a snail species which is commonly found in the Wellington area. My friend John Marston and I spent several days at the bottom of this sinkhole in 1966 looking for snails and in the process excavating a lot of bird bones. Most of these bones were sent to Ron Scarlett at Canterbury Museum. Interesting to see the log at the edge of the photo where we tied a rope to lower ourselves into the sinkhole. Our first challenge was to remove the layer of sheep and cattle remains.
    Ian Payton

    Reply
    • Trevor Worthy

      Good memory Ian – indeed this is Martinborough No 1 as known in 1901, and Harrisons Hole and some other name. Many specimens have been radiocarbon dated from this site including series of finschs duck and some moa.

    • Horace

      Harrisons after Bob Harrison? who still had some Moa toe bones.

    • Alan Tennyson

      It’s interesting to hear your recollections Ian. If you send me an email (alant@tepapa.govt.nz), I’d like to get a few more details of your trip(s).
      It seems that the cave was named after Walter Harrison – the deerstalker who ‘found’ the cave.
      regards
      Alan

  5. adele

    what an interesting find… I bet there are lots of caves around in NZ today that we don’t know about. lovely to be able to share with us all thank you

    Reply
    • Alan Tennyson

      Thanks – yes, there are still many unexplored caves & crevices in NZ that may hold similar treasures.

  6. Karen Palmer

    Fascinating. When I was a child my father took us to a cave near Martinborough to see bats. We had to wade through ongaonga. Very painful. What sort of bats – maybe long tail?

    Reply
    • Alan Tennyson

      That’s really interesting. Both long-tailed & short-tailed bats still occur – but only rarely – in the Wairarapa, so I’m not sure which species you would have seen. Perhaps they were more likely to have been long-taileds in caves on farmland? I don’t think that there are any bats left close to Martinborough now.

  7. John Flux

    Fascinating numbers, Alan. Ducks are dumb, OK; but Kakapo? They must have been thick on the ground, or are they not as bright as other parrots?

    Reply
    • Alan Tennyson

      The bird bones may have accumulated there over 1000s of years, but even so, there are a lot of kakapo down there. My guess is that kakapo were once quite abundant in the area.

  8. Siren Deluxe

    Love the ‘collecting samples’ photograph. It looks horribly difficult. A picture says a thousand words….

    Reply

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