Here Damselflies, on the Other Hand, Look Else in the World
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Contents Preface vii Natural History Damselflies and dragonflies in the natural world 1 Habitats of New Zealand damselflies and dragonflies 4 Endemics and more recent arrivals 9 Biology and behaviour 12 Conservation 51 Photographing damselflies and dragonflies 54 Damselflies, dragonflies and communities 56 Species Accounts Blue damselfly Austrolestes colensonis 60 Gossamer damselfly Ischnura aurora 66 Chatham redcoat damselfly Xanthocnemis tuanuii 72 Redcoat damselfly Xanthocnemis zealandica 78 Bush giant dragonfly Uropetala carovei 84 Mountain giant dragonfly Uropetala chiltoni 90 Lancer dragonfly Aeshna brevistyla 96 Baron dragonfly Anax papuensis 102 Dusk dragonfly Antipodochlora braueri 108 Sentry dragonfly Hemicordulia australiae 114 Yellow spotted dragonfly ‘Procordulia’ grayi 120 Ranger dragonfly Procordulia smithii 126 Red percher dragonfly Diplacodes bipunctata 132 Common glider dragonfly Tramea loewii 138 Species Likely to Establish 144 Bibliography 148 Acknowledgements 151 A teneral sentry dragonfly clings to its exuvia while hardening through the night. Preface Dragonflies – if a name should reflect The New Zealand damselfly and character, then dragonflies could not have dragonfly fauna comprises 14 species been better named. Dragons in legends, currently known to breed in the North and mythologies and fairy tales are often South Islands, Stewart Island/Rakiura and pictured as strong, fearsome, merciless the Chatham Islands. Additional species rulers of the air, but are sometimes have been recorded on the Kermadec portrayed as full of wisdom. Dragonflies Islands and others still have arrived have it all: they are strong, dynamic fliers occasionally on New Zealand’s main islands showing no mercy towards mosquitoes but have failed to establish permanent or many other small insects. What about populations. Some tropical Pacific odonates wisdom? Well, one could argue that by are gradually expanding their ranges with surviving the many major extinction events increasing global temperatures and may since the first dragonfly-like ancestor find their way to New Zealand in the near appeared on our planet – more than 325 future. This book includes all those species, million years ago – this group of insects has but local New Zealand residents are our indeed earned the label ‘wise’. Regardless, main focus because most of them are today’s dragonflies are superbly adapted to endemic, meaning that they are found only their environment. on these four main islands and nowhere Damselflies, on the other hand, look else in the world. We pay special attention completely opposite to their relatives – to what we need to know and do in order to delicate wings; slim, elongate abdomens; protect them from introduced pest animals large, wide-set eyes that track the minutiae and plants, which may deplete or smother of the world around them; subtle nuances dragonfly natural habitats and replace our of colours on their bodies in a combination unique treasures forever. that is very often pleasing, even entrancing, New Zealand’s eight endemic species to a human observer. No wonder that their sit in five genera (spread over four common name associates them with a families), three of which – Xanthocnemis, young girl. Uropetala and Antipodochlora – are entirely However, both dragonflies and damsel- endemic (the other two genera have flies have similar life histories and the species found outside of New Zealand). same general organisation of their bodies. The evidence suggests that some of our Therefore, they are combined in one insect endemics developed from ancestors that group – the order Odonata. Since there is were isolated from the rest of the world not a general common name for the whole more than 80 million years ago, after the group, people often refer to them all as break-up of the supercontinent Gondwana. ‘odonates’. Likewise, for convenience, that Subsequent generations persisted, surviving A male yellow spotted dragonfly illustrating the approach is used in this book dedicated to through New Zealand’s geomorphological association of this group of insects with flying dragons. New Zealand species of Odonata. history, which included subsidence of the VII land, earthquakes and volcanic activities, is enacted in or around the open wetlands, the formation of mountains and glaciation. rivers or temporary puddles in which So, today’s odonates are messengers, they breed. Almost all you have ever read time capsules containing encoded genetic in nature books or watched in natural information from ancient times when their history documentaries about the lives of ancestors were flying together with the mammals or birds – such as establishing predecessors of species that we now find and defending territories, finding mates on distant continents such as Australia and food, or the general struggle for and South America. existence – is easily observable from the Odonates may not possess human bank of an overgrown pond. Just book intelligence but they can certainly help your seat by bringing a chair and watch us to exercise our brains more effectively. the odonates dance over the water. Observe and remember what you see, Wetland, river, puddle, pond – the link and refer to this guide. You can go one or between odonates and freshwater is more more steps further by taking notes in the than just opportunistic. These insects field and/or recording encounters with a depend on freshwater, and many species camera or sketchbook. There is no better are quite sensitive to its quality, so the way to connect with nature. The more cleaner the waterway, the more diverse you watch odonates, the more you will be and abundant is its odonate fauna. Record enchanted. The more carefully you observe the presence of adults of each species them, the richer will be your experience. throughout the year, noting this on a In fact, damselflies and dragonflies are calendar. Keep doing this year after year. easy to observe. The life of adult odonates Do not stop. You will come to expect each Damselflies and dragonflies are easy to observe from the bank of a pond. Male gossamer damselflies are dainty and extremely pretty insects. PREFACE • ix Natural History This book includes those odonates so the New Zealand species have unique far established on New Zealand’s four features that distinguish them to some main islands as permanent or accidental extent from their overseas counterparts. residents. To date, 14 species are To make sense of New Zealand’s recognised as breeding in the North and odonates, we begin with a broad look at South Islands, Stewart Island/Rakiura and what these insects are and where they fit the Chatham Islands. There are 11 genera, in the global classification of organisms which are in turn grouped into six families. living on our planet. Eight of these species are endemic – Austrolestes colensonis, Xanthocnemis DAMSELFLIES AND DRAGONFLIES tuanuii, X. zealandica, Uropetala carovei, IN THE NATURAL WORLD U. chiltoni, Antipodochlora braueri, The branch of science called taxonomy ‘Procordulia’ grayi and P. smithii. Four deals with the naming and classification species (Ischnura aurora, Anax papuensis, of living organisms. Scientists working Hemicordulia australiae and Tramea loewii) in this field are taxonomists. They place established breeding populations in organisms into hierarchically ranked New Zealand less than a hundred years groups or taxa (singular ‘taxon’). At the ago. The remaining two (Aeshna brevistyla lowest level, similar individuals that are A female redcoat damselfly greets us at a pond’s edge in Christchurch, New Zealand. Odonates are and Diplacodes bipunctata) are also found capable of interbreeding and producing excellent indicators of water quality and they can ‘teach’ us how to manage our freshwater resources. on other Pacific islands and in Australia; fertile offspring are categorised as however, preliminary studies indicate that being of the same species. Closely species to appear at a particular time of for ideas for future studies; for guidelines the year and to fly for a specific period. on conservation activities; and as an album Suborder Family Genus Species Species common name When there are changes in your local of nature photos. For quick reference Zygoptera Lestidae Austrolestes colensonis Blue damselfly water habitats, damselflies and dragonflies in the field, you can use the separate Coenagrionidae Ischnura aurora Gossamer damselfly will be among the first to ‘tell’ you – you’ll identification chart in this book. We like to Xanthocnemis tuanuii Chatham redcoat damselfly notice fewer species, lower numbers than think that we are giving you a guide to last Xanthocnemis zealandica Redcoat damselfly usual or even different species. These your lifetime. At least, that’s how we feel Anisoptera Petaluridae Uropetala carovei Bush giant dragonfly alarm bells can prompt you to check with about these insects, which have guided Uropetala chiltoni Mountain giant dragonfly your neighbours to find out what may have our lives for more than 30 years. For us, happened and how it can be fixed. odonates have been a never-ending source Aeshnidae Aeshna brevistyla Lancer dragonfly Anax papuensis Baron dragonfly This book aims to be a broad guide of joy, wonder and intellectual stimulus. to New Zealand Odonata. Use it: as an We hope we have managed to convey the Corduliidae Antipodochlora braueri Dusk dragonfly identification manual; as a source of pleasure that we have experienced during Hemicordulia australiae Sentry dragonfly ‘Procordulia’