George Shepherd

Discovering new species

When a new species of plant or animal is discovered it’s a big news story, but the secret amongst biologists is that it’s actually easy to find a new species. It’s hard to convey to people just how many species remain to be discovered, and how few people there are left looking for them.

Undiscovered jumpers: There are over 50 species of cave wētā, or tokoriro, in New Zealand, which, despite their name, live mostly in the forest. So many new species are being discovered that there is a backlog waiting for the few entomologists who study wētā to find the time to describe and name them. Creative Commons BY-NC, Jon Sullivan / Flickr

Undiscovered jumpers: There are over 50 species of cave wētā, or tokoriro, in New Zealand, which, despite their name, live mostly in the forest. So many new species are being discovered that there is a backlog waiting for the few entomologists who study wētā to find the time to describe and name them.
Creative Commons BY-NC, Jon Sullivan / Flickr

There are probably undescribed species living in your backyard. Entomologist Willy Kuschel spent 15 years collecting beetles in the Auckland suburb of Lynfield. He found 982 species of beetle, far more than anyone would have suspected could be living 10 kilometres from the central city. Amazingly, 150 of those beetles were new to science. Nobody had noticed them because nobody had looked.

There are probably species to be discovered in Springvale and Aramoho, but if I wanted to find one I’d start at Bushy Park, one of the last remnants of lowland forest in this part of the country. Bushy Park has never had biologists do a comprehensive survey of its insects, snails, and spiders, so we have no idea what’s there. Collecting a scoop of leaf litter from the forest floor and picking through it might well reveal species surviving there and nowhere else.

The stick that moves: A new species of stick insect found only on the Poor Knights Islands was recently named Clitarchus rakauwhakanekeneke, in conjunction with local iwi Ngāti Kuri. Its Māori name means “the stick that moves”. Thomas Buckley / Landcare Research

The stick that moves: A new species of stick insect found only on the Poor Knights Islands was recently named Clitarchus rakauwhakanekeneke, in conjunction with local iwi Ngāti Kuri. Its Māori name means “the stick that moves”.
Thomas Buckley / Landcare Research

The scientists who do this sort of survey and name new species are called taxonomists and their work is the foundation of all conservation policy and ecological research; you have to be able to list and name the living things in an area before you can measure how they’re doing or develop a management plan. Taxonomic research has always been the mainstay of museums, which have large comparative collections. But museums all over the world have been cutting back, and New Zealand is no exception.

 

When I was a lad I was mad keen on lizards, and conventional wisdom was that we had a dozen or so species in New Zealand. Since we started looking closely at lizards and their DNA, it turns out there are actually about 100 species, but there are only a handful of scientists able to formally describe them and give them names. The most recent field guide to native lizards has to refer to fairly-widespread species with labels like “Genus B species 1”, because we don’t have enough taxonomists.

Thambotricha vates, a Latin name that translates as “wonder-haired prophet”, has been found by entomologists for the first time since 1996. This elusive moth has only been seen 15 times since it was described and named in 1922. Creative Commons BY-NC, XXXXXXXXXXX / Flickr

Thambotricha vates, a Latin name that translates as “wonder-haired prophet”, has been found by entomologists for the first time since 1996. This elusive moth has only been seen 15 times since it was described and named in 1922.
Creative Commons BY-NC, XXXXXXXXXXX / Flickr

Even after a species is described, we don’t know necessarily know anything about it. Recently a small moth, Thambotricha vates, was caught by Landcare entomologist Robert Hoare. It had last been seen in 1996 and only 15 specimens had been collected by scientists since it was first described in 1922. Because it’s found from Nelson to Katikati, it probably isn’t rare; we just don’t know its habitat. Although the media treated this rediscovery as a big story, it isn’t all that exceptional. There are over 1,700 species of moths in New Zealand, and some of our 10,000 insect species have almost certainly been seen just once, by the entomologist who described them.

 

In NZ there are many species of native earthworms, some of them gigantic. In all the gardens, parks, and farmland of NZ the earthworms are just a few introduced European species. Unfortunately we know very little about native earthworms; many have been found from deep in the subsoil, living in a single patch of native bush. Thirty species occur only on a single small island each, but 102 species are listed as “data deficient”. They could be widespread, or on the verge of extinction – we don’t know. And there are surely native earthworms still unknown to scientists, which might go extinct before they’ve even discovered.

A new species washed up on the beach: George Shepherd, Curator at the Whanganui Regional Museum in 1933, measuring the skull of the beaked whale that was eventually named Tasmacetus shepherdi in his honour. Whanganui Regional Museum Collection 1805.296.2

A new species washed up on the beach: George Shepherd, Curator at the Whanganui Regional Museum in 1933, measuring the skull of the beaked whale that was eventually named Tasmacetus shepherdi in his honour.
Whanganui Regional Museum Collection 1805.296.2

Not all new species are moths and worms. There are still discoveries to be made in the deep sea, even of large marine mammals. The Whanganui Regional Museum still has the skeleton of a beaked whale that washed up on the beach near Hāwera in 1933, and was collected by George Shepherd, the Curator at the time. He recognised it was unusual, and sure enough it turned out to be a new species. Shepherd’s beaked whale (Tasmacetus shepherdi) lives in deep water far from shore, in cold southern seas, so live animals have been seen only a handful of times. Most of what we know about them comes from stranded specimens.

 

New techniques can also help discover species that were hiding in plain sight. When the DNA of kiwi populations all over New Zealand was compared, the birds around Ōkarito on the West Coast turned out to be very different from other brown kiwi. Collectors in the 19th century had noticed this, and used the name rowi to distinguish them from other kiwi. The DNA evidence was enough to establish them as a new species, Apteryx rowi, numbering just a few hundred birds in one patch of forest. They now have their own captive breeding program.

Saving a subspecies: The Hector’s dolphin (Cephalorhynchus hectori) has North Island and South Island subspecies that can interbreed. The North Island form, or Maui dolphin, is in danger of extinction, but saving it shouldn’t be as high a priority as all the other actual endangered species in New Zealand. Creative Commons BY-NC, Earthrace Conservation / Flickr

Saving a subspecies: The Hector’s dolphin (Cephalorhynchus hectori) has North Island and South Island subspecies that can interbreed. The North Island form, or Maui dolphin, is in danger of extinction, but saving it shouldn’t be as high a priority as all the other actual endangered species in New Zealand.
Creative Commons BY-NC, Earthrace Conservation / Flickr

Without the attention of taxonomists the rowi might have quietly gone extinct while we were distracted by showier things like Maui dolphins (which are not actually a distinct species, just the Hector’s dolphins that happen to live in the North Island). The worst scenario is discovering much later, from museum specimens, that something collected a century ago is both a distinct species and no longer to be found in the wild. How many species have we already lost, species that we’ll never know about, because we didn’t notice them in time?

 

Dr Mike Dickison is Curator of Natural History at the Whanganui Regional Museum.

A Treasure Trove of Moa in Whanganui

Last week the Moa Gallery opened at the Whanganui Regional Museum in Stage I of a visible-storage project that sees the entire moa bone collection out of boxes in the basement to where people can see it, both in display cases and on the internet. But why is the moa collection so important? Why put it all on display?

North Island giant moa (Dinornis novaezealandiae)

North Island giant moa (Dinornis novaezealandiae)

Whanganui has been known for its moa bones since the earliest days of European settlement. As far back as the 1850s Anglican missionary Richard Taylor collected enormous bones from old pa sites and sent them to the eminent zoologist Professor Richard Owen in England. Owen was the first scientist to recognise that these bones could only be from a giant flightless bird, and coined the name Dinornis for them; a “terrible bird” in the same way a dinosaur was a “terrible lizard”.

Moa bones are found throughout the country, and collecting them was a popular hobby from the 19th century onward, so most museums in New Zealand have a moa collection. You can find the bones in caves from birds that wandered in, or fell down sinkholes; in dunes, where the shifting sand covered and protected their skeletons; or in swamps, where moa were trapped and sank into the mire, accumulating in huge numbers over the centuries.

The 1937 excavation at Todd’s Hole

The 1937 excavation at Todd’s Hole

As more of the pool was extracted, excavation continued as walls were built to hold back the liquid mud

As more of the pool was extracted, excavation continued as walls were built to hold back the liquid mud

One such moa death trap was near Ūpokongaro, up the Makirikiri Valley, in a swampy pool named Todd’s Hole on the Todd Family Farm. Beneath a thin crust of soil was a funnel of liquid mud full of moa bones, plus a few more from farm stock that had wandered in more recently. At first the bones could be just yanked out with an iron claw, but when the vast size of the deposit became clear, representatives from the Museum, with a £1200 excavation budget, began a proper excavation. Over 1937 and 1938 a crane, bucket and sluice were built, hundreds of cubic yards of mud sorted through by hand and about 2,000 moa bones extracted, cleaned and sorted.

Back at the Museum, the Curator George Shepherd began assembling skeletons from the pile of bones, putting together 10 in all. In those days moa classification was not well understood and many species were thought to be represented in the find, some from just a single bone.

Today with the help of DNA we can put the bones from Makirikiri into just three species: Mantell’s moa, a small species found around forest edges and wetlands; the bush moa, another small slender species that lived in the forest and seems to have been the most common kind of moa in the area; and the North Island giant moa, with gigantic females 1.5 m at the shoulder and weighing perhaps 200 kg, with males only half that size.

Photo of the Makirikiri Moa skeletons in the new Museum wing 1968. They’ve since been reassembled into positions more like those of a living moa.

Photo of the Makirikiri Moa skeletons in the new Museum wing 1968. They’ve since been reassembled into positions more like those of a living moa.

The skeletons were put on display in the Museum and the rest of the bones put in storage until they were re-examined in the late 1980s by moa expert Trevor Worthy. He was the first to recognise that the moa collection from Whanganui was of international importance. Although other large moa deposits had been discovered, especially in the South Island, most of those bones had been sent around the world, traded, lost, or destroyed. The Whanganui collection is one of the most important in the world because it has stayed almost completely intact, which lets scientists study an entire community of moa trapped in the swamp over thousands of years: their age, growth rate, size and male/female ratio.

These bony rings support the trachea, or windpipe, of a moa and are sometimes found in a pile in the middle of a very well-preserved skeleton.

These bony rings support the trachea, or windpipe, of a moa and are sometimes found in a pile in the middle of a very well-preserved skeleton.

The moa species that ate leaves and twigs would also swallow small stones, known as gastroliths or gizzard stones, to help grind up their food, in the same way chickens swallow pebbles and grit. Sometimes one or two kilograms of smooth stones can be found in a pile in a sand dune long after the rest of the moa skeleton has crumbled away.

The moa species that ate leaves and twigs would also swallow small stones, known as gastroliths or gizzard stones, to help grind up their food. Sometimes one or two kilograms of smooth stones can be found.

The goal of the Museum is to make this collection accessible by putting it all on exhibition and also by photographing, registering, and 3D-scanning the bones so everyone in the world can see them, not just people able to visit Whanganui. The whole process will be happening in the gallery itself, where visitors can watch and ask questions. We’re hoping that our moa collection will put Whanganui on the map, not only for moa biologists but for anyone interested in these amazing giant extinct birds.

 

Dr Mike Dickison is the Curator of Natural History at the Whanganui Regional Museum.