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.
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 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.
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.
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.
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.