For almost 50 years Christchurch ecologist, entomologist and respected author Brian Patrick has devoted his life to researching Lepidoptera species throughout New Zealand, Australia and the Pacific. He’s made it his life’s mission to encourage New Zealanders to take an interest in our significant butterfly and moth fauna to ensure it’s preserved for future generations. But despite his tireless work, the average New Zealander has little idea about the creatures fluttering along our desolate, rocky coasts or high up in the mountains.
Most Kiwis think New Zealand has just two butterflies: the white cabbage, and the self-introduced monarch. Meanwhile, misunderstood moths are deemed as nothing but a domestic inconvenience. Delve deeper though, and New Zealand is an extraordinary place to study, collect and photograph butterflies and moths, says Brian.
Brian first became fascinated with moths and butterflies as a 10-year-old boy, growing up in Invercargill. ‘I don’t know what ignited my passion,’ he says. ‘I’m just driven to know about the unknown. I’m interested in everything that’s there, not just moths and butterflies, but the whole ecology. Where they are found and the pattern of distribution. What they are feeding on, the rocks, the plants, other insects and how they interact. It just captures my imagination.’
Brian still has the handwritten records of his first trip on 1 January, 1970, to Bob’s Peak behind Queenstown. Since then, he has undertaken more than 3860 separate bug hunting trips, discovering more than 100 new species, naming many of them, including a recent publication describing a tiny moth he discovered in his lunchtime in the Christchurch Botanic Gardens. He always carries an empty tube in his pocket for such occasions.
The moth is the first Southern Hemisphere representative of a genus that feeds on the small-leaved shrub Teucrium in both hemispheres. Brian and a colleague named it Sabulopteryx botanica to celebrate its discovery in a botanic garden.
Globally, there are more than 350,000 known Lepidoptera (Greek meaning ‘scaly wings’) species, 20,000 of which are butterflies. There are around 2100 species of moth and butterfly in New Zealand, found mostly in the South Island. Of those, more than 2000 are moths, and 90 per cent are found nowhere else in the world. Today, there are only 58 recognised butterfly species in New Zealand, of which only 39 are endemic to New Zealand; the rest are blow-ins (the monarch) or accidental introductions.
Curiously, New Zealand’s endemic butterflies all belong to only two (coppers and admirals) of the five superfamilies of butterflies worldwide, says Brian. ‘New Zealand lacks native skippers, whites and swallowtails, but the two groups of butterflies we do have are pretty special. It’s just the way things happen. Even small Pacific islands have all five. It’s amazing.’
Coppers are a genus of small orange butterflies, with a certain species of boulder copper among the world’s smallest, with a wingspan of less than 2 cm. The largest New Zealand coppers have a wingspan of 3 cm. Notably, they are found on every continent except South America and Australia, but their number and diversity are unrivalled in New Zealand. Found nationwide, four are confined to the North Island, while 22 are found across the South Island. Copper larvae are particular feeders, feeding only on our five native species of pōhuehue (Muehlenbeckia), explains Brian.
New Zealand also hosts three types of admirals, more than any other area worldwide. To put it in context, North America, Hawaii, Europe and Australia each only has one. Yellow (which we share naturally with South Australia) and red admirals are widespread on the mainland where there are nettles which the larvae eat and live on, while the Chatham Island admiral is confined to the remote, exposed archipelago.
While many of the large groups of highly evolved moths are also absent in New Zealand, it’s home to many unique and primitive species, including an ancient moth family (Mnesarchaeidae) that is unique to New Zealand, and another, Micropterigidae, that evolved long before flowering plants and uses its jaws to grind fern pollen rather than sip nectar, which is only found here and in New Caledonia, explains Brian.
While they are commonly known as ‘moth’ and ‘butterfly’, there is no scientific basis for the terms, says Brian. ‘There is an evolutionary continuum from the most ancient moth group to the most sophisticated butterfly group. Some moths are more closely related to butterflies than to other moths.’
There are, however, some general differences between the two, he says. ‘Moths usually hold their wings flat while resting, have feathery antennae, and are active at night. Butterflies tend to be more brightly coloured, have clubbed antennae, hold their wings erect while at rest, and are active by day. But there are exceptions to these generalisations.’
Some New Zealand moths, especially those in the alpine zones, are brightly coloured and fly during the day, while some butterflies are unremarkable. New Zealand’s largest moth is the primitive puriri (Aenetus virescens) moth, a member of a group of moths commonly known as the ghost moth, which is found hiding deep in North Island forests, boasting a wingspan averaging 10 cm (for males) and 15 cm (for females). In the South Island they are represented by many large Aoraia moths, some with short-winged and flightless females.
Like other animals in the Lepidoptera order, the life cycle of moths and butterflies is fairly uniform, explains Brian. Because of their short-lived lives as adults (two weeks is long-lived), their focus is on reproduction. Adults must quickly find a mate and females must find a suitable place on plants or other surfaces to lay her eggs. Larvae hatch from the eggs (caterpillars), then grow and metamorphose from pupae into adults. The period of metamorphosis (where the larva encases itself in a cocoon or chrysalis while its wings grow) may last a few days or a few months, emerging at the end as an adult.
Sadly, there’s a growing body of anecdotal evidence that suggests many of our native butterflies and moths are in decline, through habitat loss, weed invasions and pests such as the German and common wasp. There is a lot being done for kiwi, kauri and kereru, but there are many people for whom those species are out of reach. Butterflies are generally all around us, wherever one lives. The plight of our butterfly fauna is heavily dependent on human respect if they are to survive and thrive. Yet many of these little beauties are teetering on the edge of survival, says Brian.
Without butterflies and moths, many of our native flowering plants could also be at risk as they are the primary pollinators, he adds. ‘They are excellent botanists. It’s a nice little symbiosis, but because it happens mostly at night, in the case of moths, people don’t see it happening. Most plants rely on it to reproduce. We certainly don’t know all the answers, but we need to work as a team to come up with realistic solutions. It’s about achieving a balance.
‘The South Island is the sixteenth biggest landmass and tenth highest on earth with just one million people, whereas Java is the seventeenth biggest with more than 92 million people; so we have no excuse not to look after nature,’ he says.
Words & IMAGES Annie Studholme