Contributions Surveys for the Eltham copper butterfly Paraluciapyrodiscus lucida Crosby (Lycaenidae) in Victoria in late 2011 E Bayes1, F Douglas2, JWhitfield3, BD Van Praagh4, RP Field5, ALYen6andTRNew7 1,3DepartmentofSustainabilityandEnvironment,POBox3100,BendigoDeliveryCentre,Victoria3554 2POBox37,Rainbow,Victoria3424 1Invert-Eco,25JacarandaPlace,Craigieburn,Victoria3064. 5,6BiosciencesResearchDivision,DepartmentofPrimaryIndustries,621 BurwoodHighway,Knoxfield,Victoria3156 andBiosciencesResearch,LaTrobeUniversity,Victoria3086. 7DepartmentofZoology,LaTrobeUniversity,Victoria3086(contact:[email protected]). Abstract RecentsurveysfortheElthamcopperbutterflyParaluciapyrodiscuslucidaCrosbyhaverevealedseveralpievi- ouslyunknownpopulations in theWimmera (1), near Castlemaine (4) and near Bendigo (1). Theirsignifi- canceisdiscussedinrelationtothebutterfly’sconservationandmanagement, includingdesignoffuelreduc- tionburningforoccupiedsites(TheVictorianNaturalist129(3),2012,114-118) Keywords: Elthamcopperbutterfly,Paraluciapyrodiscuslucida,conservation,invertebrate,management Introduction The Eltham copper butterfly Paralucia pyro- edge, itwasa primecandidatefor investigation discus lucida Crosby (ECB), is of significant in order to furthercharacterise its distribution conservation interest, and is amongst the best and seek additional populations that might be documentedthreatenedinsecttaxain Victoria, vulnerable to fuel reduction burns anticipated where it has become a notable flagship for in- for assetprotectioninareaswhere it might oc- vertebrate conservation (Canzano et al. 2007, cur (Newetal. 2012). Some occupied sites are New 2010). The few known populations, each close to residential developments, where regu- small and isolated, are concentrated in three lating fires may be both a high priority and a main regions, namelyouter north-eastern sub- verycomplexexercise to undertakesensitively. urbs of Melbourne (Eltham, Greensborough), Negotiationson optimalfireregimesto protect the central wooded countryside spanning Cas- ECB, ifthose regimes can be defined, are also tlemaine and Bendigo (with recent discover- likely to be complex. Any strictures on burn- ies in the latter area reported by Canzano and ingoperationsclosetohumansettlementsmay Whitfield 2008), and a smaller representation needverycarefulconsiderationtoachieveasset near Kiatain the Wimmera area. Thebutterfly protectionwithoutfurtherthreateninganyspe- isinvariablyassociatedwithits solelarval food cieslistedundertheFloraandFaunaGuarantee plantBursariaspinosaCav. andcaterpillarsalso Act 1988. have a mutualistic association with ants, Noto- Inthisnote,wereporttheoutcomesoftarget- ncus spp. Bursaria spinosa and identified host ed surveys for the butterfly undertaken in late species ofNotoncus are widespread, and occur 2011,basedonsearches foradultbutterflies. in many places in Victoria where Paralucia is Methods absent, some ofthese appearing entirely suit- During the main adult flight season ofP.p. lu- ableforhabitation. cida in late 2011 (November, December), sys- The ECB is one ofvery few Victorian inver- tematicsurveysoftheregionalnon-Melbourne tebrates for which site managementbycontrol populations were undertaken by trained ob- burning has been attempted in the past (New servers familiar with the butterflyand unlikely et al. 2000) and for which tentative fire pre- to confuse it with any other taxon. Surveys scriptionscanbebased on practicalexperience included known occupied and historically oc- and knowledge of the species’ biology, albeit cupiedsites,andadditionalareasofpotentially at sites near Melbourne rather than the areas suitablehabitat within the wider regions. Dur- explored here. With such background knowl- ing the time available, we have attempted to TheVictorianNaturalist 114 ) Contributions undertake sufficient additional field investiga- Salisbury Bushland Reserve, from where his- tiontoexplorethepresenceandsizeofpopula- toricalrecordsexist;asnospecimenshavebeen tionsofthe Eltham copper in all known extra- seen at Salisbury during a number oftargeted Melbourne localities, and to search for further searchesoverthelastdecade,itmaynowbeex- populations within the potential range, guided tinct there.ThemainpatchofBursariaat Salis- by presence of Bursaria, and recording such bury is fenced to exclude grazers, but current potential habitat. Although Notoncus is also a weedinvasion isanadditionalthreat. critical resource forECB, itwas not soughtdi- A previously unknown and seemingly strong rectlyon the sitesvisited. Each sitevisited was population of ECB was discovered along the characterised, its position mapped for future sides of Nursery Road abutting a Sugar Gum referenceand possiblere-survey,andpresence/ plantation on the north-east boundary ofWail absenceofadultP.p. lucidanoted. State Forest, at 54H0595925 UTM 5960515 Altogether, 15 sites in the Wimmera were (36° 29’ 47.00”S, 142° 04’17.12”E, south-east) explored (by FD). Extensive searches (coordi- to 54H0595640 UTM5960861 36° 29’ 37.87” ( natedbyJW)wereundertakenoverpublicland S, 142° 04’07.14”E, north-west). Theroadsides within the large potentially habitable region supportastrongBursariapopulationandarein around Castlemaine and Bendigo. Over a six- good natural condition. Eight newly surveyed week period, the potential habitat areas were sites,eachwithstrongBursariapatchesthatdid traversedatabout60mintervals insearchofB. not yield ECB, included those at and around spinosa as abasis for categorising habitat suit- Winiam, Dimboola, Nhill, Antwerp and West , abilityand a focusfor future searches. Around Wail. Castlemaine, 1565 ha of potential habitat in- cluded 63 core habitat sites and a further 54 CastlemaineIBendigo (Fig. 1 smallerpatches ofBursaria. NearBendigo, 980 All previouslyrecordedsites still support ECB. The great majority ofadditional sites inspect- haincluded23corehabitatsitesand26smaller ed did not yield ECB, and a number of core’ patches. These categories were separated by amountofBursaria — core habitat’ units were sites have been noted for additional survey in the future. Some are on areas that have been areaswith>200plantspresent,withthesmaller disturbed in the past, such as along roadsides patches consideredvaluable inpromotingcon- and channels. Previously unknown popula- nectivitybutlesslikelytosustainbutterflypop- tions, most recorded from individual sightings ulations. Limited time forthe surveys preclud- ed revisiting many potentially habitable sites (with low numbers possibly reflecting surveys outside the peak flight period, as for absences indicatedbypresenceofBursaria andtheseare , from other sites), were found in each region. priority for inspection to determine status of ECBinthe2012-2013flightseason.Despitethe Four were around Castlemaine, one near work reported here, much further exploration Bendigo. They are: (1) a north-facing slope south of the Castlemaine-Muckleford Road, isneededwithinthis region. and within a recently-conducted fuel reduc- Results tion burn area (55HO250766, UTM 5896499; Detailed information on all sites surveyed is 37°2' 34.9"S, 144° 1’ 55.9"E); (2) eastofYoung- available in a report submitted to the Depart- man’s Track, and in a recently burned area, ment of Sustainability and Environment (Yen as above (55H0251826, UTM 5897640; 37° and New 2012). The following is a briefsum- L 59"S, 144° 12' 40.1"E); (3) a roadside site to maryoffindingsinthetwo regionssurveyed. the south ofCastlemaine,on Dingo Park Road Wimmera (55HO255015, UTM 5892398; 37° 4' 51.9" S, Paralucia pyrodiscus lucida was confirmed C1r44e°ek14’(5452H.09"2E5)3;05(94), BUroTaMd R5o8a9d1,53C8a;mp3b7e°ll5s' present at five sites within the Kiata Flora Re- serve, which is thus endorsed as harbouring 23.8" S, 144° 13' 17.9" E); and (5) a site to the south ofBendigo between Kangaroo Flat and majorconcentration ofpopulations within the Strathdale,withsuitablehabitatextendingover region and ofsubstantial conservation impor- 30 ha (55H0257100, UTM 5924217; 36°47’ tance. However, it was not found at the nearby Vol 129 (3) 2012 115 Contributions 42. 4"S, 144° 16' 44"E). The last is regarded as themostsignificantpopulationsofECB. aprioritysite, on which largeareas ofBursaria The discovery ofseveral new populations of shouldbeexcludedfromburns. P.p. lucida isaverypositiveoutcome fromthis Discussion work. These populations all appear to be very In both regions surveyed, Bursaria is very restricted in extent, and isolated, but confirm patchy in the landscape, and numbers of the the importance ofconcentrated surveys in de- plant very variable. Many small patches are tecting such elusive and patchily-distributed perhaps unlikelyto support viable ECB popu- taxa. Despite the importance oflarge sites, the lations, andapparentlysuitable habitat patches small site areas in Eltham that have supported are sparse within the wider landscape. How- populationsforatleastseveraldecadesdemon- etvhearn, 2behcaa,uasseaErCouBndcaEnltthharmi,veisoonlatsiitoensmoafylebses sftorratceonaslesrovatthieoni.mpWoertasnucggeesotfvtehartyrsamtahlelratrheaans more relevant than size in explaining absence. leadingtoaperceptionthatthebutterflyismore Around Castlemaine/Bendigo, the large and widely distributed than previously known, the continuous populations ofBursaria as at Ka- newdiscoveriesurgeaneedforevengreatersite limna Park (Castlemaine), appear t,o support protection; thiswould enable connectivity and Fig. 1. Indicative relative posi- tions of populations of Paralucia pyrodiscus lucida within the Cas- tlemaine/greater Bendigo region: populations discoveredduringthis survey (open circles) are shown together with previously known populations (solidcircles). 116 TheVictorianNaturalist Contributions 3. protect all known populations and sites ofall furtherpopulationsnearCastlemaine,adding sizesuntiltheirrealstatusisclarified.Whilstthe tothoseintheCastlemaine Botanic Gardens newly discovered presence ofECB on recently and Kalimna Park. Two are within a Zone 1 burnedsitesisanencouragingsignofitsresist- Asset ProtectionZone,asistheBendigosite, ancetothattreatment, numbersseenwerevery and so have potential to be burnt every 5-8 low and the regimes and impacts ofthe burns yearsand tohave90% oftheareas treatedto unclear. Anyfutureburnson thesesitesshould reduce fuelhazard tomoderatelevels. heedthedistributionofthebutterflythere,and The increased documentation ofP. p. lucida be undertaken sympathetically in assuring its supports the commonly held view that popu- conservation. Theoptimal burning regimesfor lations are largely discrete (closed and demo- ECB conservation have not been investigated graphically independent) and very limited in beyond Eltham, so that such a precautionary area. However, proximityofsomeofthese (for approach seems imperative. From experiences example, at Castlemaine) leaves open the pos- in burning two sites at Eltham, wherethe but- sibility ofa metapopulation structure, so that terfly’s phenology is somewhat different from landscape level conservation management in that at the sites discussed here, burns were the regions ofoccurrence is clearly needed to considered to be safest’ ifundertaken in early oppose further fragmentation, as well as pro- autumn (when caterpillars were the onlystage mote individual management forsustainability present, were part-developed prior to winter, ofallinhabitedsites. and ableto take refugein Notoncusnests), and The other major outcome is endorsement when ‘hotspots’ ofknown abundancecould be that the butterfly is indeed absent from much protected bydamping down. However, for any apparently suitable habitat, including patches site to be burned, there is likely to be conflict closetoconfirmedpopulations.Theseabsences between community concerns and optimal based on systematic targeted searches suggest timing adjudged from biological information. (notwithstanding the ‘single visit’ limitation Thesmalloccupiedareasalso endorsetheneed noted earlier, and lack of searches for Noton- for (and wisdom of) small scale mosaic man- cusants) therealityofthebutterfly’spatchiness agement,beitbyfireorothermeans, tosustain and highly localised distribution and that it is suitability. Ideally, these should follow surveys truly ofconservation concern, rather than the to detect any ‘hotspots’ ofECB to be shielded documented distribution simplyreflecting un- from loss and, so, augment conservation ben- der-recording. Within any site, butterflies are efit from burns undertaken primarily for fuel also restricted: the newly discovered Wail site, reductionandassetprotection. for example, supports a population occupying The former population at Salisbury was not onlyabout400x30monaroadsideverge.Such rediscovered and itislikelythatthis isnowex- sites merit special notice as vulnerable to road tinct. maintenance works and similar disturbance, The majornewdiscoveriesare: and should be signalled to the responsible au- 1. a population in the Wail State Forest, as an thority for protection. However, the apparent important intermediate locality between suitability to P. p. lucida ofmany vacant sites Kiata and Castlemaine and, perhaps consti- suggeststhatthemajorcriticalresourcesforthe tutingafurther‘fragment’indicatingthatthe butterflyarenotinthemselvessufficientindica- historicalrangeofthebutterflywasmoreex- tors oflikelihood ofits occurrence: predictive tensivethan atpresent; modeling for the butterfly’s incidence cannot 2. a further population in the southern area of yet be formulated soundly, with preliminary Bendigo. We note thatthis site is within the trials based on both incomplete information area ofan Asset Protection burn scheduled and inadequate understanding. Prudence dic- for autumn 2012, and that much ofthe area tates that nopopulation isexpendableandthat explored in the region, as around Castle- all occupied sites should be conserved. Cur- maine, is within the Asset Protection Zone rent population sizes on the newly discovered susceptible to fuel reduction burning over sitesareunknown,asistheextentoffunctional thenextfewyears; isolation of butterfly populations on each. At Vol 129 (3) 2012 117 1 Contributions Kiata and at Kalimna Park, Castlemaine, it is nisation or as sites for deliberate translocation known that ECB is quite mobile andcan track shouldcurrentlyoccupiedsitesbecomeunsuit- patches of Bursaria across distances of up to ablethroughdegradationorhumanimpacts. several hundred metres (Canzano et al. 2007, Acknowledgements New2010). Largesitesadjacentto known pop- Funding for these surveys from the Department of ulations may thusbe particularly important to Sustainability and Environment, Victoria, is grate- conserve. fully acknowledged. In addition to authors, the A more general lesson is that anycontempo- ftohellBoewnindgigoco/nCtarsitbluetmeadinteortehgeione:xtPenCsliuvneies,uGrveNeyvsilli,n rary allocation of formal conservation status S Small, A Smith, TWilliams, with site mappingby to a poorly-known invertebrate taxon must be FWilson. open to review as new information accrues, References ainnfdorcmaantioonnl.yIrtarieslyunbuesufaolu,nduenfdorotnunadtefeilnyi,titvoe CapnozpaunlaotiAoAnoafndtheWhEilttfihealmdcJo(p2p0e0r8)buDttiesrcfolvyePrayraolfucaifauprytrhoe-r have support ofthe level ofthis investigation discuslucidaCrosby(Lepidoptera:Lycaenidae)inBendigo, for large-scale exploration for threatened in- CaVnizctaonroiaA.AT,heNeViwctToRriaanndNaYteunraAliLst(2102057,)1T7h8e-1E8l0t.hamcopper vertebrates across much oftheknown or likely butterflyParaluciapyrodiscuslucidaCrosby(Lepidoptera: habitat area. However, despite this substantial VLiycctaoerniiad.aeT)h:eVliocctaolrivaenrsNuastursataltiestc1o2n4ser2v3a6t-i2o4n2.strategy in effort for ECB, much habitat remains to be ex- NewTR(2010)ButterflyConservationi,nSouth-EastAustral- plored, and repeated surveyson occupied sites Neiaw:pTrRog,reVsasnanPdraparogshpeBctDs.a(nSdprYinegnerA:LDo(r2d0r0e0c)htF)ire and the are neededto confirm thebutterfly’s status and management ofhabitatqualityin an Australian lycaenid abundance. The restricted period of appar- butterfly, Paraluciapyrodiscuslucida,the Eltham copper. ency ofadults, as the stage most amenable to NeMwetaTmRo,rpVhaonsiPsra1ag,h15B4D-16a3n.d Yen AL (2012) Invertebrate rapid inspection, also limits such opportunity. conservation status and the limits of reliable informa- Whilstthenumerousnon-inhabited corehabi- tNiaotnu:raleixsatm1p2l9e,s68f-r7o6m. Victoria, Australia. The Victorian tat quality’ sites indicate priority search areas YenALandNewTR(2012)VBRCTerrestrialInvertebrates: forthe future (andfor whichsubstantial fund- surveysforselectedtaxa,2011.UnpublishedreporttoDe- partmentofSustainabilityandEnvironment,Victoria. ingwould be neededto furnish a more defini- tive picture ofECB incidence), theirwellbeing within a mosaic of largely unsuitable habitat maybeimportantforthefutureofthebutterfly Received22March2012;accepted26April2012 either as resources amenable to natural colo- Cicada. Photo by Dan Carey. 118 TheVictorianNaturalist