I Trc pe zo st i gm o ste nolobo. Dragonflies DeserLJewels \-/ Tony Start , long beforethe ageof dinosaurs, m (oier 2 ft) hunteA in a primeval t flytng animals, and they are the Dragonflies make up one Suborder of the Order Odonata. The other Suborder contains the damselllies. Although damselflies are frequently referred to, mistakenly, as dragonflies, the two groups are easily distinguished (SeeTable). Odonatans are usually diurnal (daytime) predators which rely on eyesight. They feed on other insects which they capture on the wing. Some speciescruise continuously in search of prey or mates. Others spend much of their time at rest, watching for passing victims. After mating many speciescontinue to fly in 'tandem' as the female lays eggs either inserted into aquatic vegetation or dropped freely onto water. We usually associate dragonflies with water. In Australia their lawae always live One of lhe few specieswilh o common nome islhe emperordrogonfly in fresh water, where they are (Hemionoxpopuensis). voracious predators of other A mole Agriocnemis kunjino. aquatic animals. Predictably, the greatest diversity of Australia's 300 odd speciesis in the warmer, wetter parts of the continent: the top end and the eastem seaboard of Queensland. The arid Pilbara worlld seem an unlikely place to find these aquatic insects. It is, at fust, astonishing to find bright red dragonflies on the tops of spinifex<lad hills and huge emperor dragonflies in mining town suburbs. Nevertheless, DRAGONFLY,DAMSELFLY OR ANTLION? 33 species(22 dragonflies and Theonly insectsthat looksuperficially like adult dragonflies or 11 damselflies) occur in the damselfliesare adult antlions which b€longto anotherinsect Pilbara. Ten of them are endemic orderrthe Neuroptera. to the region and many have appropriate names e.g. Nosostictapilbara, DRAGONFLIES Nannophlebia injibandr (for the Are relativelylarge and powerfulinsects. Aboriginal people who lived Holdtheirwings out horizontallywhen dt rest. near Millstream), and Eurysticta Havehuge eyes that occupy mostof their head. c<nlawanyah for Calawanyah Haveminute whisk€r-lik€ antennae. Station. Their larvae have evolved to DAMSELFLIES make use of all the potential Are small,delicate ins€cts. habitats that are available. Some Foldtheir wings over theirbacks like butterflies wh€n at rest. speciesthat are able to complete Hav€smaller eyes that arewidely separated. a life cyde in a few weeks take Hdvemicroscopic, whisker-like antennae. advantage of temporary pools ANTLIONS filled by thunderstorms. Many Ar€ smalfto-m€diumsized insects. others take a year (some need Foldth€irwings to theirsides, like moths, when at rest. severalyears) to matue. They Havesmaller, wid€ly separatedeyes. need permanent water, usually Hdveprominent clubbed antennae. deep pools, but a few of them 45 larger often setding on streams' other fine vegetation, often less the Pools, can only live in flowing There is always than 5 cm from the water thick b-ullrushes. Just as the larvae of different on still The former live near an excePtionto the rule; speciesoccuPY different habitats, surface. the latter like still davs N. Pilbara will hover the adults have divided their small streams; thriving around very amongsithe caieP9tt"P.tg environment into manY niches' water, even 9.- soaks' above the steams ln wtucn tney the delicate shallow, almost stagnant Because breed. weak In contrast PseudaSflbn damselllies are relativelY can exPloit a aurmfrons, a brilliant Paleblue Dragonllies fliers, they seldom flY high or of habitats a golden head and much leater variety havel far. TinY, white insect with the becausethey are such Powertul k:r/ina (named for thorax, skims fast over Agriocnemis fliers. There are, of course, manY Millstream) surfaceof larger, Permanent Kuniina sPring, near seldom venture far oools while its near relative P' sDeciesthat and orange, black and blue -microcePhalum, but a bright blue from their breedhg $ounds, Ischnuraaurora weave their waY the margins of some are higNY nomadic, through dense beds of grass and species,Patrols lschnuraouroro. MillslreomNolionol Pork, o hoven tor o vorielv of species.lbelowj exploiting ephemeral pools and even the vast dry plains and mountain ranges. For example, within one day of the fust storm in nearly a year, I found eight speciesof dragonflies patrolling a creek in the hills behind Karratha. The sheam had flowed for a few hours, leaving a series of pools which lasted no more than ten days. On another occasiory Charlie Nicholson of the Department of Conservation and Environment encountered hundreds of dragonflies of three speciesalong about three kilometres of the N.W. CoastalHighway between Whim Creek and Port Hedland. The insectswere flying back and forth over spinifex growing on flat, dry, red, sandy plains. At least in the Pilbara, there are dose links between habitat requiements of larvae and the distribution of adults. Three groups can be recognised. o Specieswith larvae that can lhis Zwommo elgnel is elegonily live in temporary pools. Many comouflogedogoinsl lhe bork, Thisspecies flies only of dusk. of them are very common. [obove) They include some of the nomads which are found on hill tops and out in the A temole Agriocnemis kunjina spinifex. posingos port of lhe vegetqiion. o Specieswith larvae that need (right) permanent water. They are usually found near pools that are suitable breeding sites. Xonthog on eMhroneurum. (below) Being so restricted, they are vulnerable to changes of water quality and of adjacent ve8etahon. o Specieswith larvae that only live in permanent running water. The adults never venture far from their breeding sheams. Permanent streams are rare in the Pilbara, and all Until last year, however, the dragonflies and damselflies Millstream was the only source in this group are endemic and of the West Pilbara water supply rale. (to Dampier, Karratha, Wickham, Pt. Samson and Cape Millstream Lambert). Pumping through a Millstream is unique. Here in seriesof dry years from the the arid Pilbara is an extensive aquifer at Millstream reduced the system of pools, springs, streams water level sufficiently to and dry creeks. seriously deplete spring flows, All of the Pilbara's 33 threatening the habitat of the Odonatans are found at rarest of these insects and other Millstream, and severalof those inhabitants of the wetlands that depend on running water (many of which have not yet s are found nowhere else, been studied). 47 To ensure that these beautiftrl and rare insects are able to thrive, Conservation and Land Management Department officers, with the assistanceof Dr Jan Taylor, have established a program to monitor the dragonflies and damselflies at Millstream, and the Water Authority of W.A. has installed bores and pumps to supplement I the natural springs. I Last year the Harding Dam held water for the fkst time. Whenever possible, the dam will supply the water requirements of the coastal towns. This will help to take the pressue off Millstream, assuring the s dragonflies a more securefuture. (i It will also mean that there is a new, huge, permanent body of water. Early indications suggest that the dragonflies and damselflies are making full use of this new opportunity. Pseu d a g ri o n mi c roc ePho l u m. $oP) Oihetr um migrolum. (letl\ ThisCrocolhernis nlgdfrons looks like it would be ot a homeon one of Mohet'simpressionistic lily ponds. \s (below) 48 La^dscope. Volume2 No.2 SummerEdition 1986/87 A Conflictof Interests Whyare there so manyconflicts when it comes toour natural environment? There is conflict amongindustrial groups exploiting natural resources;environmentalists advocating Contents Page preservationof wildlife;government agencies; and recreationgroups. Savingthe Whales Inan idealworld we would have a total KeiranMcNamara understandingabout ecosystems and natural resources,and of the long term needs of the BungleBungle: Birth of a NationalPark community.But this is notan idealworld, and much LianaChristensen and Chris Haynes . .17 ofthe conflict stems from a lackol agreement aboulenvironmental imoact and human needs- Snowscapes,W.A. ... .zo Takewhale strandings for instance. From the timewhales beach, tissue damage occurs due to a risein bodytemperature and the sheer weight of HerdsmanLake: lnner City Sanctuary themammal. We don't know how long they have to John Blyth and Stuaft Halse .28 liethere and how hot they have to get beforethe - chancesof survivalare next to nil.Strandings may WetlandReflections a photoessay bepart of a naturalculling process or accidents Text:Phill Jennings Photog raphs: J iri Lochm an causedby human impact on the environment. DerekMead-Hunter . .35 And,what about the people who turn out in large numbersunder often adverse conditions, and Burninglrom Experience becomeso emotionally caught up in savingthese Co eenHenry-Hall .43 creatures?What weight do we put on their need? It is notan idealworld. We are a longway from Dragonflies- DesertJewels knowingthe answers to toomany important TonyStart . .M ouestions- Thereis a needfor more lnvestigation, better communicationand a broaderunderstanding Crocodiles- A Conservation of Conundrum environmentalorocesses and human needs. Clitf Winfield .49 Thisbrings us to Landscopeandits purpose. Itsprime objective is to achievean understanding UrbanAntics-aregular aboutconservation of ecosystemsand living-with-natureseries. .54 managementof naturalresources. Landscope'saim is to provideexpert information Letters . onthe major conservation issues, latest developments,research in progressand general leaturesof