Burrowing
Crayfish
Group
Recovery
Plan
DEPARTMENTofPRIMARYINDUSTRIES,WATERandENVIRONMENT
Acknowledgments
ThanksareduetoDrPierreHorwitz andAssociate Professor Alastair Richardsonfortheirinputandcommentsonthisplan,aswellasthecontinued interestoffieldnaturalistgroups(particularly JimNelsonandtheCentral NorthFieldNaturalists),theLauncestonEnvironment Centre,volunteersand theForestPracticesBoardincollectingdataandinformation onthesespecies. ThanksarealsoduetoDrSallyBryant, PeterBrownandthestaffofthe ThreatenedSpeciesUnitfortheirsupportandadvice.MarkWapstra,Helen Glassick, Rob King, Serena King and Parks and Wildlife field staff (particularlyonFlindersIsland)providedvaluableassistanceinthefield.
ThisrecoveryplanwaspreparedbyDrNiallDoranandwasproducedwithsupport fromtheNaturalHeritageTrust.TheCommonwealthformallyadoptedtheplanin
2001.
Citation:Doran,N.E. (2000).BurrowingCrayfishGroupRecoveryPlan2001-2005. DepartmentofPrimaryIndustries,WaterandEnvironment,Hobart.
Copyright©StateofTasmania
Thisworkiscopyright.Itmaybereproducedforstudy,researchortrainingpurposes
subjecttoanacknowledgmentofthesourcesandnocommercialusageorsale.Requestsand enquiresconcerningreproductionandrightsshouldbeaddressedtotheManager,Threatened SpeciesUnit.
ISBN:0 724662480
Insidephoto:Engaeusorramakunna(N.Doran)(ListedasVulnerableonThreatened
SpeciesProtectionAct1995).
Frontcoverphoto:
Contents
SUMMARY...... 4
CURRENTSPECIESSTATUS...... 4
HABITATREQUIREMENTSANDTHREATENINGFACTORS...... 4
RECOVERYPLANOBJECTIVES ...... 4
RECOVERYCRITERIA...... 4
RECOVERYACTIONSNEEDED...... 4
BIODIVERSITYBENEFITS...... 5
INTRODUCTION...... 6
DESCRIPTION...... 6
TAXONOMICSTATUS...... 6
DISTRIBUTION...... 6
HABITAT...... 6
ABUNDANCE...... 7
LIFEHISTORY...... 9
THREATENINGPROCESSES...... 9
SPECIESIN DETAIL...... 10
ENGAEUSORRAMAKUNNA...... 10
ENGAEUSSPINICAUDATUS...... 11
ENGAEUSYABBIMUNNA...... 12
ENGAEUSMARTIGENER...... 13
EXISTING CONSERVATION MEASURES FOR ALLSPECIES...... 16
STRATEGY FOR RECOVERY...... 17
RECOVERY OBJECTIVES & CRITERIA...... 18
RECOVERY ACTIONS...... 19
ACTION1. ASSESSMENTOFHABITAT ...... 19
ACTION2.IMPROVEMENTOFRESERVATIONSTATUS...... 20
ACTION3. HABITATMANAGEMENT:AGRICULTURE...... 21
ACTION4. HABITATMANAGEMENT:FORESTRYANDCOMMERCIALHARVESTING...... 22
ACTION5. HABITATMANAGEMENT:URBANANDOTHERLANDMANAGERS...... 23
ACTION6. COMMUNITYINVOLVEMENTANDEDUCATION...... 23
ACTION7. POPULATIONANDHABITATMONITORING...... 24
ACTION8. ORGANISATIONALSUPPORT...... 25
IMPLEMENTATION SCHEDULE...... 26
REFERENCES...... 27
Summary
Current Species Status
FourTasmanianEngaeusspeciesareofconservationsignificance.TheMt.Arthur,Scottsdale,Burnie andFurneauxburrowingcrayfish(E.orramakunna, E.spinicaudatus, E.yabbimunna,andE. martigener,respectively) arecurrentlyalllistedunderboththeTasmanianThreatenedSpecies ProtectionAct1995andtheCommonwealth EnvironmentProtectionandBiodiversityConservation Act1999.Thefirstthreehavealsobeenidentified asPrioritySpeciesrequiring recoveryactionunder theTasmanianRegionalForestAgreement1997.
Habitat Requirements and Threatening Factors
All four species are endemic to Tasmania and have highly restricted distributions. Habitat requirements aregovernedbywaterqualityandavailability,andthepresenceandqualityofsoiland nativeriparianvegetation.Threateningprocessesincludeurbanandindustrialpollution,inappropriate agricultural andforestryactivity,longtermfireeffects,clearanceandremovalofnativevegetation, sedimentation, andwaterwaydisturbanceoralterationofdrainage.Eachofthefourspecieshasbeen subjectedtodifferingdegreesofeachoftheseprocesses.
RecoveryPlan Objectives
Overallobjective
Tostabiliseandimprovetheconservation statusofthesespeciessothattheymaybeconsideredfor downlistingaccordingtopopulationsizesandtrends,areaandoccupancyandsecurityofhabitat withinorbeyondthetimespanofthisplan.
Specificobjectives
1. Improvehabitatprotectionforeachspecies.
2. Increasepublicawarenessandinvolvementinthreatenedspeciesprotection.
3. Ensureeachspeciespersistsinthelong-termthroughoutitsareaofoccupancy.
RecoveryCriteria
1. Improvedsecurityforeachspeciesthroughreservation,improvedlandusetechniquesand management agreementswithlandholdersandforestry,agriculturalandurbanorpublic stakeholders.
2. Increasedpublicawarenessofthesespeciesandinvolvementinorwillingnesstobeinvolvedin conservationrelatedprograms.
3. Eachspeciesmeasuredatselectedmonitoring sitesindicatesoverallstabilityorlong-termincrease inpopulationsorrange.
RecoveryActions Needed
1. Assessmentofhabitat(particularlyforE.martigener).
2. Improvementofreservationstatusforallspecies.
3. Habitatmanagementwithinagriculturalareas.
4. Habitatmanagementwithinforestryandcommercialharvestingareas.
5. Habitatmanagementwithinurbanandotherareas.
6. Communityinvolvementandeducation.
7. Populationandhabitatmonitoring,combinedwiththeresultsofactions1-6(asabove).
EstimatedCostofRecovery(2000pricesin$000s/year)
ScientificOfficersalaryoncostsaredividedbetweenindividualactions.
Actions / 1.1 / 1.2 / 2 / 3 / 4 / 5 / 6 / 7 / 8.1 / 8.2 / Total2001 / 45.3 / 14.4 / 67.6 / 11.7 / 11.8 / 16.1 / 13.3 / 20.4 / 41.6 / 0.4 / 242.6
2002 / 79.9 / 41.6 / 23.4 / 40.6 / 13.3 / 23.4 / 34.0 / 0.4 / 256.6
2003 / 79.9 / 41.6 / 23.4 / 40.6 / 13.3 / 23.4 / 34.0 / 0.4 / 256.6
2004 / 6.4 / 23.4 / 8.0 / 0.4 / 38.2
2005 / 6.4 / 23.4 / 8.0 / 0.4 / 38.2
Total / 45.3 / 14.4 / 227.4 / 94.9 / 58.6 / 97.3 / 52.7 / 114.0 / 125.6 / 2.0 / 832.2
Costingsdonot incorporatecommunity andvolunteertime.
BiodiversityBenefits
ProtectionandmanagementofthefourEngaeusspecieswillhavedirectconservationbenefitsfor otherstream-dwellingandstream-associatedspecies(including Nationallylistedspecies)withinthese areas.Itwillalsohavedirectbeneficial consequencesforwaterqualityandwaterwayhealthaffecting theBurnieandDorsetcommunities. OnFlindersIsland,theStrzeleckiNationalParkhasbeen identifiedascontaining significant areasofhabitatthathavebeenlostfromelsewhere ontheBass StraitIslands(Walsh1999).Inaddition tothecrayfish,theparkcontainsvaluableandhighlevelsof biodiversity,andisnotedasbeingofhighscientificinterest“duetothehighnumberofendemic species,rarefloraandfaunaandsignificantvegetationcommunities”itcontains.
Introduction
Description
SpeciesofEngaeusare smallfreshwatercrayfish,withageneralbodylengthofundertencentimetres. Theyvaryincolourfromorangetoreddishbrown,grey-blue andpurple.Duringthebreedingseason (latespringtosummer), femalescarrylargeorangeeggsandrecentlyhatchedyoungundertheirtail. Theyarebelievedtoeatrottingwood,detritus,rootmaterialandoccasionallyanimalmaterial.
MostspeciesofEngaeusare characterisedbytheir ability toburrow,oftentoconsiderabledepths,and specimensareonlyrarelyseenabovegroundorinstandingwater(Horwitz1990a).Burrowsoften havechimneys ofpelletedsoilwheretheymeetthesurface,andinshelteredareasthesemaybequite high (upto40cm). Burrowscanbesimpleandshalloworcomplex,deepandextensive,andaburrow systemmayoftenbetheproductofseveralgenerations ofcrayfishactivity.Burrowsmaybedirectly connectedtostreamsorlakes(type1),mayconnecttothewatertable(type2),ormaysimplyrelyon run-offtostaywet(type3).Thoserelyingsolelyonrun-offareonlyfoundinAustraliaandare specifictoEngaeusspecies,makingthemthemostterrestrialoftheworld'sfreshwater crayfish (HorwitzRichardson1986).Consequently, theirdispersalthroughwaterwaysmaybelimited, leadingtorestrictedrangesandahighdegreeoflocalspeciation.
Taxonomic Status
Engaeusisoneoffourfreshwater crayfishgeneranativetoTasmania,theotherthreebeing Parastacoides,Geocharax,andAstacopsis.Thegeneracanbedistinguishedonthebasisofchelae (claw)orientation andshape,carapacegrooves,andthelocationandnumberofspinesonthebody (Horwitz 1988a).Thereare35speciesofEngaeusfoundinsouth-eastAustralia,20ofwhichare endemictomainlandAustralia, 13areendemictoTasmania, andtwoarefoundinboth.Horwitz (1990a,1994) hasrecently reviewedthetaxonomicstatusofthegenus,inwhich hedescribedthefour speciescoveredhere.
Distribution
Tasmanian Engaeusspeciesaremostlyfoundinthenorthandwestofthestate,withboththenorth- eastandnorth-westcharacterisedbytheirowndistinctsubgroups.Thedistributionofsomeofthese hasbeenextensivelystudied(Horwitz1986,1988b,1990a1996;DoranRichards1996;Doran
1998).
Thegenusdisplaysremarkablediversitygiventherelativelysmallgeographicareaoverwhichit occurs,andischaracterisedby ajig-sawpatternofdistinctandinterlockingrangesforindividual species.Overlapbetweenspeciesdoesoccur,butisnotthenorm.Somespecieshaveverywide geographicranges,whileothersareveryrestricted.FourTasmanianEngaeusspeciesareof conservationconcernduetotheirsmallranges:
E.orramakunna(theMt.Arthurburrowingcrayfish), E.spinicaudatus(theScottsdaleburrowingcrayfish), E.yabbimunna(theBurnieburrowingcrayfish)and
E.martigener(theFurneauxburrowingcrayfish).AllfourofthesespeciesareendemictoTasmania
(Figure1:Mapofgeneraldistributions).
Habitat
Allburrowingcrayfishspeciesfavourwet,muddyareasandseepages,wheretheirburrowsexhibit characteristicchimneysofpelletedsoil.Particularspeciesvaryinthelevelofwateravailabilityand otherenvironmentalconditionsthattheytolerateand/orprefer.Suchdifferencesarereflectedinthe longitudinal('sourceto mouth')andtransverse('acrossgully',ordistancefromstream/water) distributionofspeciesalongawatercourse(SuterRichardson1977,Horwitzetal.1985,Horwitz
1986,RichardsonHorwitz1987).
Abundance
Burrowingcrayfishcanbelocallyabundantinanyareaofsuitablehabitatwithintheirrange.Given the unpredictablenatureofhabitattypeswithin widergeographicregionsandtheoftensmallseepages inwhichthesespeciesoccur,themostreliablepopulation estimateshavebeenmadeforE. spinicaudatus(thespeciesforwhichavailablehabitathasbeen mostcloselydocumented).Overatotal
3.465x106m2identifiedassuitablehabitat,Horwitz(1991)estimatedtheoverallpopulationofE. spinicaudatusas1.36-2.67x106 adults,accordingtoburrowdensitiesandoccupanciesinboth disturbedandundisturbed land.Richards(1997)increasedtheestimatedavailablehabitatforthis speciesby0.022squarekilometres, withthediscoveryofthespeciesinasmallstripoflesserquality habitatwithinitsrange.Thisincrease wasestimatedtorepresentapproximately1000individuals,and sodoesnotsignificantlyalterHorwitz'soriginalestimate.
EstimatesforE.orramakunna, E.yabbimunna,andE.martigeneraremoredifficult,asthesespecies coverlargerareaswhichhavenotbeensurveyedatasfineascaleovertheirwholerange.Rough population estimatescanbemadeforthesespeciesbycouplingthegeneraldensity/occupancy estimatesdeterminedforE.spinicaudatus(Horwitz1991)coupledwithknownlocationsandranges, GIS-projections ofavailablehabitat,anddegreeofpotentialdisturbanceofthathabitatasrelatingto tenurewithineachrange.Engaeusorramakunnamayvaryfrom1.38-4.04x106adults,E. yabbimunnafrom2.29x105to1.65x106adults,andE.martigenerfromonly2.20x104to1.42x
105adults.Givengoodhabitat,thepotentialsizeoftheseEngaeusspeciescoloniesmaythereforebe quitelarge,despitebeinggeographicallyrestricted.
Figure 1: General distribution of threatened burrowing crayfish in Tasmania
Life History
Relativelylittleisknownaboutthelifehistory ofEngaeusspeciesingeneralandofthesefour species inparticular.Ofthefour,themostdetailedinformationisavailableforE.spinicaudatus(asbelow: Horwitz1991).Thelifehistoriesofthethreeotherspecies(E.orramakunna, E.yabbimunna,andE. martigener) arelikelytofollowsimilarpatternswithminorvariationsbetweenspecies.Allmaybe foundwithvaryingsize classesofyoungwithintheirburrows,and individualsmayshowsomedegree ofvariationinmorphologicalfeaturesandsexualcharacteristicsbetweenandwithinsites(Horwitz
1990a,DoranRichards1996,Doran1998,unpublisheddata).
Threatening Processes
Thefourspeciesareofconservation concernduetotheiracutelyrestrictedrangesandareasof occupancy,andthepresenceofactivelythreateningprocesseswithinthese(Horwitz1990b,1991
1994,GaffneyHorwitz1992,DoranRichards1996,Doran1998).Threatening processes particularly include those that affect water quality/quantity, and soil and food (wood/plant) availability.
Theseinclude:
•agriculturalprocessesincludingstock grazing(which churnsandcompactssoil),damconstruction, clearanceofriparianvegetationandploughing;
•forestry activities (eg clearing, burning, conversion to plantation) which impose significant mechanicaldisturbanceonstreamheadwatersandseepagechannels(towhichcrayfishmay display varyingdegreesoftolerance);
•bothagricultureandforestrymayhavesignificanteffectsviaalterationofdrainageandsiltation characteristics,the application and timing of fertilisers and pesticides, and hazard reduction burning;
• highintensityfiresandtheconsequenteffectsonvegetationandhabitatquality;
• urbanimpacts,viawastemanagementpolicies,waterwaypollutionandhabitatremoval;
•general roading and drainage activities (urban and non-urban) impacting on seepage/wetland/stream bankhabitatquality,andanyactivities(egalluvialmining)thatdegrade riverbankintegrityandenhanceerosion.
While allofthese impactshavethepotentialtoaffectburrowingcrayfishhabitat qualityoverthelong term,crayfish areatmostriskfromtheseactivitiesatperiodswhentheyaremoulting, visitingthe surface,matingornurturing young(Horwitz 1991).Itshouldalsobenotedthatintroducedspecies, suchasthemainland yabby(Cheraxspp.),mightcarryparasites anddiseases, andmaypreyonor competewithnativecrayfishforfoodandhabitat(Horwitz1990b).
Species in Detail
Engaeusorramakunna
Distribution
TheMt.Arthurburrowing crayfish(MtABC),isknownfromarange(extentofoccurrence) of approximately300squarekilometrescentredon Mt.Arthurinnorth-eastTasmania.Occupancywithin thisareaisnotknown,butsuitablehabitat iscommon.Thespecies extendstonearLilydale, Nabowla andSouthSpringfield,andacross thisrangebordersonthedistributionsofE.tayatea,E.nulloporius, E.mairenerandE.leptorhynchus(DoranRichards1996,Doran1999,unpublished data).Itisalso foundinthevicinityofLaunceston, althoughthesouthernboundarytoitsdistributionremains undefined.Atitsnorth-eastextreme,E.orramakunnaextendsintoanareaofsignificantbiological diversityandevolutionaryimportanceforbothburrowingcrayfishandtheTasmanianfaunaasa whole(Horwitz1996).
Habitat
Engaeusorramakunnaprefersmoistseepsandflatswampyormarshylandfeedingintoornextto streams andrivers,butcanalsobefoundinstream banks,wetpasture,culverts,androadsidedrains (DoranRichards1996).Thespeciesmayconstructburrowsinbothtype2and3habitats(Horwitz
1990a).
Lifehistory
BreedingforE.orramakunnamaybegininlatewinter.FemaleE.orramakunnahavebeenfound carryingundifferentiatedeggsinmid-June,earlyAugust,lateOctoberandearlyNovember(Horwitz
1990a,DoranRichards1996).Onsomeoftheseoccasions maleshavebeenfoundoccupying the sameburrow(Horwitz1990a).
Threateningprocesses
Amajorproportion(41%,Table1)ofthedistributionofE.orramakunnaisinStateForest,andsois subjecttoextensive forestryactivity(theeffectsofwhichmaybeminimisedforE.orramakunnawithintheprovisions oftheForestPracticesCode).Intheremainder ofitsrangethespeciesisalso subjecttoheavypressurefromagriculturalactivityonprivateland(approx52%),forwhichnocode orguidelinesareinplace.
Conservationstatus
EngaeusorramakunnaiscurrentlylistedasVulnerableundertheTasmanianThreatenedSpecies Protection Act(1995)accordingtoguidelinesfromtheScientificAdvisoryCommittee (SAC).The speciesisalsolistedasVulnerableundertheCommonwealthEnvironmentProtectionandBiodiversity ConservationAct(1999)basedonIUCN(1994)criteria.AccordingtoEFN-modifiedcriteriafor sessile species (asperKeith1998), E.orramakunnasatisfiestheguidelinesforVulnerableunderboth StateandCommonwealthActsas:
• itslinearrangeislessthan50km(RuleB);
• itsextentofoccurrenceislessthan2000km2(RuleB);
• 90%of matureindividualsoccurin10orlesspopulations(CriteriaB1);
•thereisacontinuingdeclineorpotentialdeclineduetotheoperationofthreateningprocesses throughoutitsrange(CriteriaB2).
AlthoughE.orramakunnaislikelytobethemostsecureofthefourspeciescoveredbythisrecovery plan,thereareinsufficientdataonthelongtermeffectsoftheabovethreateningprocessesonthe species.ThespecieswasidentifiedasaCategory2faunaspecies(requiringacombination of reservationandmanagementprescription,withprotectionrequiredinareasofhighqualityhabitat) undertheTasmanianComprehensive RegionalAssessmentprocess(TasmanianPublicLandUse Commission1997).IthasultimatelybeenidentifiedasaPrioritySpecies"...requiringrecoveryaction"
under the TasmanianRegionalForest Agreement(Attachment2, Part A.1) signed between the
CommonwealthofAustraliaandtheStateofTasmaniainNovember1997.
Engaeusspinicaudatus
Distribution
The Scottsdale Burrowing Crayfish (SBC), is found north of Scottsdale within an area of approximately 34.5squarekilometres,containing only3.45squarekilometresofsuitablehabitat (Horwitz 1991, Gaffney Horwitz 1992, Richards 1997). The extent of this distribution has previously beenwelldefined(Horwitz1991),andisunlikelytobeextendedfurther.Engaeusspinicaudatusiscloselyboundedby thedistributionsofE.mairener,E. tayatea,andE. leptorhynchus. RecentdiscoveriesalsoindicatethatE. orramakunnamaybe foundcloseto the southernextentofthis species (Doran,unpublisheddata).Giventheextremelyrestricted distributionofE.spinicaudatus,the entirenaturalhabitatinwhichitoccursshouldbeconsideredcriticalhabitatforthefutureofthe species(DoranRichards1996).
Habitat
Engaeusspinicaudatusisprimarilyfoundinwetbuttongrassandheathyplains(particularlywith peatyandsaturatedsoils),butalsooccursinsurfaceseepages,thefloodplains ofcreeks(oftenwith scrubbyortallertea-treevegetation),wetareasconvertedtopasture fromanyoftheprecedinghabitat types,andsomecreekbanks inopendryeucalyptforest(Horwitz1991,Richards1997). Burrowsfor thisspeciestendtobetype2(Horwitz1990a).
Lifehistory
FemaleE.spinicaudatusbecomereproductivelymatureoncetheyreachanoccipitalcarapacelength (OCL)of16.4mm,andmayundergoapre-copulatorymoult(whichpossiblyreleasesmating pheromones andreducesheraggressiveability).MatingoccursbetweenmidNovemberandlate December,andmayrepresent theonlytimethatmalecrayfishwillbefoundopenlywandering onthe surface(insearchoffemaleburrows). FemalescarryeggsandlarvaethroughDecember andJanuary, withlightorangeundifferentiated eggsdevelopingearlylimbsandeyespots,followedbyclear developmentofthelimbs,abdomen,telsonandcarapace.FemaleE.spinicaudatushavebeenfound withfreeyoungintheirburrowinMarch(Horwitz 1990a).Whileastronglinearrelationship exists betweenbodysizeandfecundityinE.spinicaudatus, noinformationexistsregardingtherateof growth,survivorship andrecruitment, age,ornumberandfrequencyofbreedingevents(e.g.biennial orsingular)forthisspecies.
Threateningprocesses
ForestryandagriculturalactivitiesalsoprovidethemainthreatstoE.spinicaudatus, alongside downstreameffectsofroadconstruction,quarryingandtheimpactsofinappropriatefiremanagement. HotfiresposeadirectthreattothepeatysoilsinwhichE.spinicaudatusisfound,whiletheabsence offiremaypromotesuccessional changeandeventualdryingofthebuttongrasscommunitiesupon them.Theacuterangerestrictionofthisspeciesmakestheidentificationandameliorationofsuch impactsapriority,particularlyaslittleoftheavailablehabitatforthespeciesfallswithinreserved areas(Table2)andalthoughsomehabitathasrecentlybeenincorporated intotheNorthScottsdale ForestReserve,management issuesandmitigationofthreateningprocesseshavenotyetbeen adequatelyresolved.
Conservationstatus
Engaeus spinicaudatusis currently listed as Endangeredunder both the TasmanianThreatened SpeciesProtectionAct(1995)andtheCommonwealth EnvironmentProtectionandBiodiversity ConservationAct(1999)duetotherestricteddistributionofthespecies,itsnegligiblereservation status andcontinuedthreateningprocessesthroughoutitsdistribution.Thespecies satisfiesthecriteria forEndangeredbasedonEFN-modifiedcriteriaforsessilespecies(asperKeith1998)underboth StateandCommonwealth(IUCN)Actsas:
• itslinearrangeislessthan20km(RuleB);
• itsextentofoccurrenceislessthan500km2(RuleB);
• 90%of matureindividualsoccurin5orlesspopulations(CriteriaB1);
•thereisacontinuingdeclineorpotentialdeclineduetotheoperationofthreateningprocesses throughoutitsrange(CriteriaB2);
• ofthe90%ofmature individualsin5orlesspopulations,nopopulationsarefreeofClassIthreats
(CriteriaF1).
Duetotheacuterestriction ofitsrangeandlargenumberofdirectlythreateningprocesses, E. spinicaudatuswasidentifiedas aCategory1faunaspecies(requiringprotectionofallpopulationsand habitatwithinitsknownrange)undertheTasmanianComprehensive RegionalAssessmentprocess (TasmanianPublicLandUseCommission1997).Ithasultimatelybeenidentifiedas aPrioritySpecies "...requiring recoveryaction"undertheTasmanianRegionalForestAgreement(Attachment2,Part A.1)signedbetweentheCommonwealthofAustraliaandtheStateofTasmaniainNovember1997.
Engaeusyabbimunna
Distribution
TheBurnieBurrowingCrayfish(BBC)isknownfromanoverallareaofapproximately 130square kilometres coveringBurnieandtheareaimmediatelytothewest.Thespecieshasonlybeenknown since1992,whenitwasdiscoveredbyMrBillWalkeroftheBurnieCityCouncilwithinBurniePark. OriginallyonlyknownfromfragmentedpopulationsonShorewellCreek,RomaineCreekandthe easternarmofCooeeCreekwithinurbanBurnie(Horwitz1994,DoranRichards1996),the recordeddistribution ofthespecieswasextendedwhenitwasfoundinSeabrookCreekbyMrJim Nelson in1998.SubsequentsurveyworklocatedE.yabbimunnaalongCampCreek,DistilleryCreek, twosmallinterveningcatchmentsandonesmalltributaryoftheCamRiver(Doran1998).Further searchinghaslocatedotherEngaeusspeciesinsurrounding areas,butnonewsitesfortheBBC.A largegap(atleast18squarekilometres)separatesthesmallereastern(urban)andlargerwestern (newlydiscovered)populationsofE.yabbimunna,includingthelowerreachesofDistilleryCreek,the CamRiver,Messengers CreekandCooeeCreek(includingthewholeofthewesternarm).Other Engaeusspeciesborderingonorwithintherange ofE.yabbimunnaincludeE.fossor,E.cisternarius, E.cunicularius,andE.disjuncticus.Engaeus fossorappearstodominatealongthecoastinthese streams,andmaycoexistwithE.yabbimunnawheretherangesofthetwospeciesoverlap(Horwitz
1994,Doran1998).
Habitat
Engaeusyabbimunnapreferswell-covered,slowlydrainingstripsoffern-dominatednativeriparian vegetation. The species is known from stream banks and seepages retaining remnant riparian vegetation withinBurnie(Horwitz1994,DoranRichards1996)andoutsidethecity,inopenand grassysheeppasture,farmdams,roadsideseepsandculverts,sedgeymarsh,andsomemoderately disturbedstreamsides(Doran1998).Burrowsareoftenoftype2.
Lifehistory
AlargemaleandfemaleE.yabbimunnawerefoundtogetherinearlySeptember(Doran1998),ata proximityalmostcertainlyrepresenting courtshipandmating(A.Richardson,personal communication). Large numbers of berried female E. yabbimunna have been found in early December,allcarryingeggsinearlydevelopmental stages(Horwitz1994).Welldeveloped/hatching larvaehavebeenfoundunderthetailofE.fossor(inthesameregionasE.yabbimunna) inJanuary (Doran,unpublisheddata).
Threateningprocesses
ThegreatestthreatstoE.yabbimunnaarewaterpollution, waterdiversionandhabitatremovalwithin theurbanenvironment.Thereissomeevidencethatamarkedreductioninpopulationsizeand
distribution hasoccurredinresponsetodecreasingwaterqualityandincreasingurbanandindustrial pollutionatthecentreofthespecies'distribution. Theabundance ofotherburrowingcrayfishspecies alsoappearsmarkedlyreducedinthemorepollutedstreamsfallingbetweenthetwodistributionsof theBBC.AswithE.spinicaudatus, thereservationstatusofE.yabbimunnaispoor(Tables12). Given the restricted amount of good quality habitat available to this species and the limited informationavailableonitsresponsestodisturbance,areaswhereagriculturalandforestryactivities areinprogressarealsoofconcern.
Conservationstatus
EngaeusyabbimunnaiscurrentlylistedasVulnerableundertheTasmanianThreatenedSpecies Protection Act(1995)accordingtotheguidelines fromtheSAC.Thespeciesisalsolistedas VulnerableundertheCommonwealth EnvironmentProtectionandBiodiversityConservationAct (1999),basedonIUCN(1994)criteria.According toEFN-modifiedcriteriaforsessilespecies(asper Keith1998),E.yabbimunnasatisfiestheguidelinesforVulnerableunderbothStateand CommonwealthActsas:
• itslinearrangeislessthan50km(RuleB);
•itsextentofoccurrenceislessthan2000km2 (RuleB);
• 90%of matureindividualsoccurin10orlesspopulations(CriteriaB1);
•thereisacontinuingdeclineorpotentialdeclineduetotheoperationofthreateningprocesses throughoutitsrange(CriteriaB2);
• ofthe90%ofmatureindividualsin10orlesspopulations,nopopulationsarefreeofClassI
threatsandnonearefreeofClassIIthreats(CriteriaF1F2).
Duetoitsrestrictedrange andthelargenumberofdirectly threateningprocessesoperatingwithin that range,thespecieswasidentifiedasaCategory1fauna species(requiringprotectionofallpopulations and habitatwithinits knownrange) under the TasmanianComprehensiveRegionalAssessment process(TasmanianPublicLandUse Commission1997).Ithas ultimatelybeenidentifiedasaPriority Species"...requiringrecoveryaction"undertheTasmanianRegionalForestAgreement(Attachment
2,PartA.1)signedbetweentheCommonwealth ofAustraliaandtheStateofTasmaniainNovember
1997.
Engaeusmartigener
Distribution
TheFurneauxBurrowing Crayfish(FBC),haspreviouslyonlybeenknownfromisolatedlocationsat highaltitudeonMtStrzeleckionFlindersIslandandMtMunroonCapeBarrenIsland(Horwitz
1990apersonalcommunication). Recentsurveyworkhaslocatedthespecieselsewhereinthe StrzeleckiNationalPark,aswellasintheDarlingRangeonFlindersIsland(Doran,unpublished data).ThereisatransitionfromE.martigenertoE.cuniculariusatloweraltitudes.Engaeusmartigenerisclearlyof veryrestricteddistribution,althoughlittleisknownofitsavailablehabitatand numberswithinthesethreeregions.
Habitat
Engaeusmartigenerhaspreviouslyonlybeenknownfromboggyareasandsmallclearwatercreeksin highaltitudewetfernygullies(Horwitz 1990a,DoranRichards 1996).Theseareasagainappearto bethestrongholdofthespecies,althoughrecentsurveyworkhasalsolocatedpopulations atlower altitudes,andinpoorlydrainedmossytea-treebogandasmallgrassyspring/soakinopendry eucalyptforest(Doran,unpublisheddata).Thespeciesoccupiesatype2burrowhabitat(Horwitz
1990a).
Lifehistory
Reproductivelyactive,andeggorjuvenile-bearing, E.martigenerfemaleshavebeenfoundin November andDecember(Horwitz1990a).Verysmalljuvenileshavebeenfoundindividuallywithin largerburrowsystemsinNovember(Horwitz1990a),whilebothsimilarjuvenilesandolder,free-
swimming individuals (dispersing insurfacewaters)havealsobeenfoundinMarch(Doran unpublisheddata).
Threateningprocesses
Althoughthereservation statusofthespeciesappearstoberelativelyhigh,potentiallycatastrophic processesstillthreatenitsstatus.OneofthegreatestpotentialdangerstothestatusofE.martigeneris theriskofwildfire.Theaccumulation ofhighlevelsoffuelthroughouttheStrzeleckiNationalPark, and the lackofaccessfor fire controlmeansthat highintensityburns may pose adangertothespecies inthefuture.Although insomeareasthecrayfishappearabletoburrowdeepenoughtoavoidthe directeffectsofdisturbancessuch asfire, long termconsequencesofintenseorrepeatedburnsmaybe catastrophic.Problems includetheexposureandlossoferosion-pronegraniticsoilsintheregion,and thelossofwaterretentionwithintheremaining soilsofthegullies. Thefloraintheupperreachesof Fotheringate Creek(typelocalityofE.martigenerandcontainingexceptionalhabitatforthespecies) hasbeenidentifiedasthemostfire-sensitive, andpersistsasrainforestremnantslargelyduetothe protectionofthesurroundingtopography(Walsh1999).
Theefficacyofsuchprotection,however,maybelostorreducedinperiodsofdrought(egCollett
1998).Similarfernywetgullieshavealreadybeencompletelylostduetothecombination offireand droughtonDealIsland(Doran,unpublisheddata),andtheseareunlikelytoregenerateforcenturies (S.Harris,personalcommunication).Somelevelofferndie-offhasalreadybeenobservedunder currentdroughtconditions onFlindersIsland(PWSstaff,FlindersIsland,pers.comm.).Incontrast, frequentburningofgulliesonCapeBarrenIslandmayproduceasimilareffect.
Forestryandagricultural issuesarecurrentlyoflittlerelevancetoE.martigener,althoughthismay changedependinguponfuturedecisionsregardingsuchactivitiesontheisland,anyfutureextensions totheknownrangeofthespecies,andchangestothestatusofunallocatedCrownland.Feralpigs havepreviouslybeenidentifiedasapotentialrisktothespecies;whileburrowdepthwouldagain appeartoprotectcrayfishfromthedirect effectsofsuchdisturbance,thisisalsoanissuethatneedsto beaddressed.
Conservationstatus
EngaeusmartigenerislistedasVulnerableundertheTasmanianThreatenedSpeciesProtectionAct (1995)andasEndangeredundertheCommonwealth EnvironmentProtectionandBiodiversity Conservation Act(1999).ThespeciessatisfiestheVulnerableclassificationbasedonEFN-modified criteriaforsessilespecies(asperKeith1998)underbothActsas:
• itslinearrangeislessthan50km(RuleB);
• itsextentofoccurrenceislessthan2000km2(RuleB);
• itsareaofoccupancyislessthan50ha(RuleB);
• 90%of matureindividualsoccurin10orlesspopulations(CriteriaB1);
• thereisapotentialcontinuingdeclineduetotheoperationofthreateningprocesseswithinits range
(CriteriaB2);
• itoccursin5orlesspopulations(CriteriaD2).
Giventhepoordistributional dataavailableforthisspecies,itcurrentlyalsosatisfiesthecriteriafor EndangeredunderbothActs,asevidencedbyitsconservationstatusattheCommonwealthlevel. Furtherdistributional workneedstobeconductedtoconfirmthatanEndangeredclassificationisnot requiredandthatVulnerableismoreappropriate.
Thespecieshasnotpreviouslyreceivedanymanagement attention,butduetotheacuterestrictionof its rangeandthepresenceof potentiallythreateningprocesses(alsooperatingwithinnewlydiscovered partsofitsrange),itisnowrecognisedasaspeciesrequiringrecoveryaction.Suchactioncanbe effectivelycombinedwiththemanagementrequiredby theotherEngaeusspeciescoveredinthisplan.
Table1:ApproximateTenureBreakdownofTotalDistributionalArea(ExtentofOccurrence)
ofRelevantSpecies
Species / Mt ABC% / SBC
% / BBC
% / FBC
Consres / 1.29 / 6.59 / 0.01 / Unkn
NCres / 0.17 / 0.77 / 4.64 / Unkn
Public / 5.31 / 15.23 / 0.09 / Unkn
SF / 41.46 / 51.60 / 3.57 / Unkn
Private / 51.77 / 25.80 / 91.69 / Unkn
Total(ha) / 29 910 / 3465 / 8 218 / Unkn
Table2:ApproximateTenureBreakdownofEstimatedAvailableHabitat(PotentialAreaof
Occupancy)ofRelevantSpecies
SpeciesMtABC
%
SBC
%
BBC
%
FBC
Consres0.983.330Unkn
NC res / 0.50 / 0 / 3.92 / UnknPublic / 6.34 / 18.71 / 0.21 / Unkn
SF / 26.43 / 39.22 / 4.36 / Unkn
Private / 65.75 / 38.74 / 91.51 / Unkn
Total(ha) / 797 / 390 / 258 / Unkn
Consres=conservationreserves
NCRes=non-conservationreserves
Public=otherpublicland(includingunallocatedCrownland) SF =stateforest
Private=privateland
Existing Conservation Measures for all
Species
Theconservation statusandpotentialthreateningprocessesforthesefourspecieswereidentifiedby Horwitz(1990b,1994).Engaeusspinicaudatushassubsequentlyreceivedspecificattentionintwo studies(Horwitz1991,GaffneyHorwitz1992),whilebackground information anddraft management prescriptionswerecompiledforallfourspeciesduringtheTasmanianRFAprocess (DoranRichards1996).Followup workhasaddedfurtherinformationon thedistributionandstatus ofE.spinicaudatus(Richards1997),E.yabbimunna(Doran1998),E.orramakunna(Doran1999), andE.martigener(Doran,unpublisheddata).
WhileE.orramakunnaandE.spinicaudatusareknowntooccurwithinsomelargeformalreserves (Doran& Richards1996),E. yabbimunnaisnot. Similarly,althoughE.martigenerisfoundwithinan existingNationalPark,thepercentageofitsdistributioninformalreservesiscompletelyunknown.
AllspeciesexceptE.martigenerarecurrentlyincorporated inanotificationandconservation prescription systemestablishedbytheForestPracticesBoard(FPB)andtheThreatenedSpeciesUnit (TSU)toadviseforestryoperations withinsensitiveareas.Forestryoperations inareasaffectingthese crayfishspecieshavebeensuccessfullymodifiedinconsultation withlandholders,forestryoperators, theFPBandtheTSU.Long-term monitoringprogramshavebegunonthesespeciestoprovide feedbackinformationontheeffectivenessofconservationmeasurescurrentlyinplace.
While nospecificregulationsgovern agricultural,industrial,civicorotherprocessesthreateningthese species,initiativeshavebeenundertaken toincreaseawarenessofthemandtheirconservation requirements. Landownershavebeencontactedtomakethemawareofthespeciesandtoascertain theirplansandattitudestowardsthelandinquestion,andworkhasbeenundertaken towards establishingmanagementagreementsandcovenantsonrelevantprivateland.
Contacthasbeenmadewithrepresentatives ofrelevantCouncils(Burnie,Dorset)regardingspecific developmentsandtheirinterestsandconcernsintheprotectionofthesespecies.Issuesrelatingto EngaeusmartigenerhavebeenincludedwithinthedraftmanagementplanfortheStrzeleckiNational Park(Walsh1999),andthepresence ofthespecies hasbeennotedasapotential issueforthefuture developmentofunallocatedCrownlandonFlindersIsland(ArtemisPublishingConsultants1999).
Publicawarenessofthesespecieshasalsobeenraisedthroughschoolandcommunitytalksanda seriesofmagazine,pressandnewsletterarticlesatlocal,stateandnationallevels.Schoolprojects conducted under permit on Engaeus yabbimunna have won one Burnie school a place in the UniversityofSydneyEurekaSchoolsPrizeforBiologicalSciences,andhaveledtoastudentfrom thiscollegebeingselectedasthefirsteverAustralianrepresentative intheStockholmJuniorWater Prize.Thisstudenthastravelled toSwedentopresentatalkonthisspecies,itshabitatandthreats, therebyraisingawarenessofE.yabbimunnaataninternationallevel.
Strategy for Recovery
The RecoveryPlancoversafiveyearperiod.Theoverallaimoftheplanistomanagehabitatin therangesoftherelevantspecies,inorderto:
•maintainorimprovewateravailability(especiallyinseepages);
•maintainorimprovewaterquality(againstpollutants,pesticides);
•maintainorimprovehabitat(nativeriparianvegetationandsoilintegrity);
•excludedisruptiveprocessesfromsensitiveareas(seepages/marshes/streamsideareas)
•increasethereservation/protectionofthesespeciesonCrownandprivateland
•increasepublicawarenessandappreciationof,andinvolvementin,threatenedspeciesprotection.
Eightprimarystrategiesunderlietheactionsdescribedintheplan.Theyare:
1. assessmentofhabitat
2. improvementofreservationstatus
3. habitatmanagement:agriculture
4. habitatmanagement:forestryandcommercialharvesting
5. habitatmanagement:urbanandotherlandmanagers
6. communityinvolvementandeducation
7. populationandhabitatmonitoring
8. organisationalsupport.
Recovery Objectives & Criteria
Thelongtermobjectiveistoreducetheimpactofthreateningprocessesuponthefourspecies,to improvetheirreservationstatusandtoincreaseourunderstandingoftheminordertoavoidtheneed toupgradetheirstatusto morecriticalIUCN(1994)conservationcategories.
Theobjectivesofthisrecoveryplanandthecriteriaforsuccessfullyachievingthemare:
SpecificObjectivesCriteriaforSuccessActions
Improvehabitat protectionfor each species.
Improvedsecurityforeach speciesthroughlandacquisition orreservation,improvedlanduse techniquesandmanagement agreements withlandholdersand
forestry,agricultural andurbanor public stakeholders.
1.
2.
3-5.
Assessment of habitat.
Improvement ofreservation status.
Habitat management with relevant groups.
Increasepublicawarenessand involvement inthreatenedspecies protection.
Increasedpublicawarenessof thesespeciesandinvolvement in orwillingnesstobeinvolvedin conservationrelatedprograms.
6. Community involvement and education.
Ensureeachspeciespersistslong- termthroughout its areaof occupancy.
Each species measured at selected monitoringsitesindicatesoverall stability or long-termincrease in populationsorrange.
7. Populationandhabitat monitoring,combinedwiththe results ofactions1-6(asabove).
Recovery Actions
Theactionsinthisrecoveryplanarebasedoncurrentknowledge ofthebiologyandecologyofthese burrowingcrayfishspecies.Managementrequirementshavebeenbasedontherecommendations of DoranRichards(1996),augmentedwithsubsequentworkinsupportofthecurrentplan.Actions willneedtobereassessedasknowledgeimproves.
Action 1. Assessment of Habitat
1.1 AssessmentofhabitatforE.martigener
Beforerecoveryactionscanbeeffectivelyimplemented onthesespecies,properassessmentoftheir distributionandthequantity,qualityandlong-term securityoftheiravailablehabitatneedstobe undertaken. Suchinformation willallowmodellingofthesespecies,andpredictionsofthelevelof habitatlossthatcanbesustainedforeachaccordingtohabitattypeandtenure.
DistributionmappingisnearlycompleteforE.orramakunna,E.spinicaudatusandE.yabbimunna, buthasnotbeenundertaken forE.martigener. Giventhesignificantdegreeofhigh-intensity firerisk posedforthisspeciesanditshabitat,itisthereforeaprioritythatdetailedsurveyworkofthe StrzeleckiPark,DarlingRange,theMtMunroandMtKerfordregions(andotherlikelyareas)is undertaken priortoanysignificant fireeventpassingthroughtheseareas(Abbott1984).Subsequent surveyandcensuswork shouldalsobeconductedintheaftermathofserious burnswithin theseareas. Ideally,suchdatashouldbecollected overanumber ofyearspreandpost-firetoensurethatvalid assessmentscanbe made(CampbellTanton1981,Majer1985,Friend1995).
Adraftmanagement planfortheStrzeleckiNationalParkhasrecentlyidentifiedtheprotectionofE. martigeneranditshabitatasapriorityforthepark,andidentifiesthecollectionofdistributional informationandaddressingotherdatagapsaskeyactionsoffuturemanagement(Walsh1999).It shouldbenotedthatadequatecareandprecautionsshouldbe takenduringsuchwork,giventheaccess requiredtoisolatedareas,thepotentialtotransportmuddymaterialbetweentheseareas,andthe currentproblemsregardingcinnamonfungusdisease(Phytophthoracinnamomi)withinand surrounding boththeStrzeleckiPark(Walsh1999)andtheDarlingRanges(ArtemisPublishing Consultants1999).
Asrecoveryandmanagement actionsforE.martigenercanonlybeeffectivelyestablishedoncethe rangeandabundance ofthespeciesandthequalityandquantityofhabitatinwhichitisfoundare known,fieldsurveysandmappingneedtobeundertaken onFlindersIslandandCapeBarrenIsland. Endangered SpeciesProgramfundsarerequiredtocoverthesalaryofaScientificOfficeranda TechnicalAssistant,fieldequipment, travelallowancesandvehiclecosts(includingairandsea transporttoremoteareasonbothislands).Contributions fromtheResourceManagementand ConservationDivisionoftheDepartmentofPrimaryIndustries,WaterandEnvironmentareincluded.
Costs($1,000’s)
Year / Yr1 / Yr2 / Yr3 / Yr4 / Yr5 / TotalCost / 45300 / 45300
1.2 AssessmentofhabitatforE.orramakunna,
E.spinicaudatusandE.yabbimunna
Ashortperiodofsurveyworkisrequiredtofinaliseamanagement overviewofthedistributionand habitattypesoccupiedbytheremainingthreespecies,andtodeterminethedegreeofmanagement or protectionrequiredforthesehabitatcomponents.Inparticular,thisworkwillfocuson:
•thenorth-eastcornerandsouthernextremesofE.orramakunna(wherethespeciesisexposedto increasingagricultural,forestryand,potentially,urbandevelopment);
•anyfurtherpotentialareasofsuitablehabitatwithinorneartherangeofE.spinicaudatus, particularlyCrownland(whichmaybe morereadilyprotectedandreserved);and
•thedistributionofE.yabbimunnaaroundtheCamRivercatchment(amajorcatchment subjected toheavyindustrialandurbandevelopment initslowerwaters,andincreasingforestryactivityin itsupperwaters).
Endangered SpeciesProgramfundsarerequiredtocoverthesalaryofaScientificOfficeranda TechnicalAssistant,fieldequipment,travelallowancesandvehiclecosts.Contributions fromthe ResourceManagementand ConservationDivisionofthe DepartmentofPrimaryIndustries,Waterand Environmentareincluded.
Costs($1,000’s)
Year / Yr1 / Yr2 / Yr3 / Yr4 / Yr5 / TotalCost / 14400 / 14400
Action 2. Improvement of Reservation Status
EngaeusspinicaudatusandE.yabbimunnainparticularareofpoorreservationstatus.Noneofthe listedEngaeusspeciesarerecognisedasreceivingadequateprotectionbymanagement prescription, reservation,or"existingmechanisms" (TasmanianRegionalForestAgreement1997;Attachment2, PartsA.2A.3).Inter-agencydiscussionsneedtobeheldthroughthisplanandothermechanismsto identifypotentialareasforthereservation ofthesespecies.ThisissueiscriticalforE.spinicaudatusandE.yabbimunna.Severalpreviousrecommendations havelistedincreasedreservationforE. spinicaudatusasapriority(Horwitz1991,GaffneyHorwitz1992,DoranRichards1996). InclusionofE.spinicaudatushabitatwithintheNorthScottsdaleForestReservehasincreasedthe reservationstatusofthespeciesbutuntilmanagementissuesareresolveditsstatusremainsprecarious.
Itwillbenecessary toassessandprioritise specificCrown,publicandprivatelandandgeneralareas withintherelevantcatchmentsforbothformalandinformalreservation.EndangeredSpeciesProgram fundsarerequiredtocoverthesalaryofaScientificOfficer,fieldequipment, travelallowances and vehicle costs, as well as the purchase, inducement, covenant or compensation and ongoing managementoflandinvolved.Contributions fromtheResourceManagementandConservation DivisionoftheDepartmentofPrimaryIndustries,WaterandEnvironmentareincluded.
Costs($1,000’s)
Year / Yr1 / Yr2 / Yr3 / Yr4 / Yr5 / TotalCost / 67600 / 79900 / 79900 / 227400
Action 3. Habitat Management: Agriculture
In consultation with landholders, it is planned to develop both general and specific voluntary guidelinesfortheprotectionofthese speciesonagriculturalland.These guidelineswould bebased on theprescriptionssuccessfullydevelopedandimplementedinconjunctionwiththeforestryindustry, butwouldbetailoredtothefarmenvironment(asperDoran1999).Theguidelineswouldaimto alleviateagricultural impactsoncrayfishspecies(throughcattletrampling,damconstruction,riparian clearing,andotheractivities)withoutimposingonnormalfarmproductivityandoperation.Thiswill beachievedbyrecruitinglandholderswhoareinterestedinworkingwiththeThreatenedSpeciesUnit todevelopbothageneralvoluntaryagricultural code(whichcouldalsohavelargerscaleandmore generalbenefitsforriparianhabitatsasawhole)aswellasspecificprescriptions andrehabilitation techniques forparticularsituationsandfarms.Wherepossible,suchguidelines willbefittedwithin larger scalestrategiesthatarebeingdevelopedtomanageagriculturalactivities,andwillinturnmake referencetosuchmajordevelopmentsastheSummerRainsprogram.
Animpactassessmentofexistingagriculturalactivitieswillbeconductedthroughouttherangeof eachspecies,andappropriateconservation strategieswillbediscussed,developedandimplemented withaffectedagriculturalstakeholders. Partofthisactionwillinvolvetrialingmodifiedagricultural practices(egpartialrehabilitationofselectedstreamanddamsides) todeterminehoweffectivelythey willcontinuetomeetfarmoperationalrequirements whileimprovinghabitatqualityforthecrayfish and related fauna. Depending upon the management and operational needs of specific farms, guidelinesandrehabilitationcouldinclude:theretentionorre-establishmentofriparianstripsor habitatclumps;therelocationofsensitivespeciespriortotheundertaking ofsignificantworks; incorporationof'speciesfriendly'aspectstothedesignoffarmsdamsandothersignificantworks; reductionofsiltationcharacteristicsandenhancementofseepages;theintroductionoffencingand otherlimitationsofcattle/livestock accesstosectionsofcreekanddambanks;andminimisationof chemicalandpesticidedriftintocreeks,damsandsurroundingareas.
Aswiththedeveloping forestryprescriptionsoutlinedbelow,manyofthesemodificationstoexisting farm practices could, ultimately, be incorporated into such works in future with minimal inconveniencetothelandholder.Othermodification/rehabilitationworkmayhavetobeconducted separatelyorsubsequenttosuch works.Asthese would potentiallyinvolvesignificantadditionalcost, theycouldbesupportedthroughtherecoveryprogrambytargetingkeycatchmentsandproperties, andbyinteractingwithreceptivelandholders preparedtovolunteertheirland.Individuals and communitygroupshavealreadyindicatedtheirinterestinbecominginvolvedwiththiswork.
Endangered SpeciesProgramfundsarerequiredtocoverthesalaryofaScientificOfficer,field equipment,rehabilitation inducementsandtrials,travelallowancesandvehiclecosts.Contributions fromtheResourceManagement andConservation DivisionoftheDepartmentofPrimaryIndustries, WaterandEnvironmentareincluded.
Costs($1,000’s)
Year / Yr1 / Yr2 / Yr3 / Yr4 / Yr5 / TotalCost / 11700 / 41600 / 41600 / 94900
NB:Thesecostsdonotincorporate Council,volunteerorcommunitytime.
Action 4. Habitat Management: Forestryand Commercial Harvesting
Thegenericandspecificguidelinesdevelopedforcommercialandnon-commercialforestryactivities inareascontainingthesespeciesneedtobeevaluatedandrefined.Dependingonindividualsituations, theseguidelineshaveincludedcombinationsofthefollowing:enhancedbufferstripsizesbeyond thosestandardfortheForestPracticesCodeandincreasedprotectionofnativeriparianvegetation; buffersizesindividuallytailoredtospecificsituationswhererequired;re-establishment ofnative riparianandunderstoreyvegetationin areaswhereit haspreviouslybeenlost;exclusionofmachinery, sitepreparation,planting’sandpesticide/fertiliserapplicationfromidentifiedandimportantpre-class
4drainagelines;spotandsub-surfacepesticide/fertiliserapplicationnearsensitiveseepageareas;the typeofpesticide/fertiliser chosentominimisepotentialharmtocrayfishspecies,withthetimingof application avoidingperiodsofcrayfishactivityandincreasedrunoff;operationsconductedwith particularcareregardingmaintenance ofwaterqualityandavailabilityinwaterways;alllandingsand crossingsconstructedwithmaximumcareregardingstreambankandbeddamage;anddisturbance avoidedinanyareaswhereburrowsarevisible.
Such co-operative development has so far been successful, with initial indications that E. orramakunnaiswellprotectedbythegeneralprovisionsoftheForestPracticesCode(Doran& Richards1996).Giventhelargepercentage oftherangeofthisspeciesthatissubjecttoforestry activity,however,longtermmonitoringofpopulationsinplantationandnativeforestareasshouldbe establishedandcontinuedpre-andpost-harvest.
Theimpactsof forestryactivitiesonE. spinicaudatusandE. yabbimunnaarelesswellknownandalso requireattention.ThedifferenthabitatandburrowtypesoccupiedbyE.spinicaudatusmayleavethe species morepronetotheeffectsofforestryactivities (Horwitz 1991),whiletherestricted rangeofE. yabbimunnacombinedwithlimitedavailabilityofgoodqualityforestedhabitatandthelackof records ofthespeciesinharvestedareasdemandsthatitbetreatedwithcautionuntilmoreinformationis available.Successfuldevelopment andimplementation ofconservationprescriptionsadditionaltothe ForestPracticesCode(asrecentlydevisedinconsultation betweentheTSU,theFPBandprivate forestryconcerns)alsoneedtobeencouragedandevaluated.
Impactassessmentofexistingcommercialandnon-commercial forestryworkswillbeconducted throughouttherangeofeachspecies.Agreementsforthelong-term managementofthesespecieswill thenbediscussed,developedandimplemented withtheFPB,ForestryTasmaniaandprivateforestry stakeholders. Wherepossible,theseagreementswillbeintegratedwithinagreedbroaderscale operationalmanagementstrategies,includingongoingmonitoringoflongtermsurveysites.
Endangered SpeciesProgramfundsarerequiredtocoverthesalaryofaScientificOfficer,field equipment,travelallowancesandvehiclecosts.ContributionsfromtheResourceManagementand ConservationDivisionoftheDepartmentofPrimaryIndustries,WaterandEnvironment,andthe ForestPracticesBoardareincluded.
Mostofthecostsofthisactionwillbeincurredinlong-term monitoring(Action7).Habitat management costsshouldbenegligibleasthesecanbeimplementedthroughexistingFPB/TSU mechanismsandthroughtheeducationandmonitoringprotocolsbelow.
Costs($1,000’s)
Year / Yr1 / Yr2 / Yr3 / Yr4 / Yr5 / TotalCost / 11800 / 23400 / 23400 / 58600
Action 5. Habitat Management: Urban and Other Land Managers
UrbanimpactsmainlyaffectE.yabbimunna,althoughsomeCouncil-relatedissues(e.g.roadand drainconstruction,streamandriverrehabilitation) alsoaffecttheotherspecies.Inaddition,relevant landmanagement issuesmayaffectCouncilsandregulatingbodiesincontrolofreservesandnon- urbanareas.
TheRecoveryPlanaimstobothincreaseawarenessofthesespecieswithintherelevantCouncilsand to workwith theseCouncilsto developappropriatemanagementguidelinesfor their respective regions.Animpactassessment ofhabitatchangeduetourbanzoninganddevelopment willbe conducted, andappropriate conservationstrategiestoalleviatethesechangesandassociatedpressures willbediscussed,developedandimplementedwithaffectedurbanstakeholdersandotherrelevant landmanagers.Partofthisworkwillinvolvecommunityinvolvementandeducation,asbelow(6).
Workswillrangefromsmallscalealterationstostreambankcharacteristics tolargerscaleprograms addressingstreamsiderevegetation andwaterquality.Theseactionswouldspecificallytargetthe rehabilitation ofstreamswithinurbanBurnie,bydevelopingaprogramwiththeBurnieCityCouncil toaddresswaterquality/pollutionissuesandpromotenativestreamsiderevegetation.Thevalueof thesecrayfishtotheBurniecommunitywillalsobepromoted:theyprovideareliableindicatorof waterquality,withcorrespondingbiodiversityandcommunitybenefits;theyarecheaperandprovide a longer-termmeasureofsuchconditionsthancorrespondingsingle-pointchemicaltests;andthey havealreadybroughtnationalandinternational recognitiontothecitythroughtheawardofstudent prizes.Individuals andcommunitygroupshavealreadyindicatedtheirinterestinbecominginvolved withthiswork.
Endangered SpeciesProgramfundsarerequiredtocoverthesalaryofaScientificOfficer,field equipment,revegetationandrehabilitationtrials,travelallowances,vehiclecostsandcommunity groupsupport.Contributions fromtheResourceManagementandConservationDivisionofthe DepartmentofPrimaryIndustries,WaterandEnvironmentareincluded.
Costs($1,000’s)
Year / Yr1 / Yr2 / Yr3 / Yr4 / Yr5 / TotalCost / 16100 / 40600 / 40600 / 97300
NB:Thesecostsdonotincorporate Council,volunteerorcommunitytime.
Action 6. CommunityInvolvement and Education
Theinterestandinvolvementof thecommunityisavitalcomponentin theongoingprotectionof these species,andindividualsandcommunitygroupshavealreadyindicatedtheirwillingnesstobecome involvedwith thiswork. TheRecoveryPlan willaimtomaintainincreasinglevels ofpublic exposure toburrowingcrayfish,andwillactivelypromotecommunityparticipationintheirprotection.
Improvedinterpretation ofthreatenedspecieshasbeenhighlightedasapriorityfortheStrzelecki NationalPark(Walsh1999)andincreasedpublicawareness andeducation haspreviouslybeen recommendedforTasmania’sburrowingcrayfishspecies(DoranRichards1996).Informationon thespecies,theirhabitatrequirementsandtheirrelevancetoenvironmentalhealthwillbedistributed toandmadeasaccessibleaspossibletolandholders, industry,schools,communitygroupsand individuals.Thisinformationwillhighlightwhatcanbedonetoimprovehabitatandwaterway quality,andwillbeupdatedtopromotethesuccesses thatareachievedinallareasofthisplan (includingforestry,agriculturalandcivicactions,andthecommunityinvolvementincorporatedwithin these).The benefitsofprotectingthesespeciesand theirenvironmentwill alsobepromoted,alongside theirpositiveprofileforthreatenedspeciesingeneral-giventhattheirconservation requirements are relativelyeasilymetwithlittletonodeleterious effectonproductioncropsorotheragricultural, industrialorcivicneeds.
EndangeredSpeciesProgramfundsarerequiredtocoverthesalaryofaScientificOfficer,equipment andtrials,travelallowances, vehiclecosts,andcommunitygroupandeducationalsupport. Contributions fromtheResourceManagement andConservation DivisionoftheDepartmentof PrimaryIndustries,WaterandEnvironmentareincluded.
Costs($1,000’s)
Year / Yr1 / Yr2 / Yr3 / Yr4 / Yr5 / TotalCost / 13300 / 13300 / 13300 / 6400 / 6400 / 52700
NB:Thesecostsdonotincorporate Council,volunteerorcommunitytime.
Action 7. Population and Habitat Monitoring
Long termmonitoringwillneedtobeconductedonthese speciesinordertodeterminetheefficacyof recoveryactions.Additionalandconcurrentinvestigationsontheecologyofthesespecieswillprovide furtherinformationonpopulationstructures,includingsurvival,recruitmentanddispersalrates,which canbeusedtofurtherrefinetherecoverystrategy.TheeffectsoffireonbothE.martigenerandE. spinicaudatusneed tobedetermined,andprovisionforthesespecies mayneed tobeincorporatedinto firemanagementstrategiesdevelopedby therelevantauthorities.
Insupportoftheactionsoutlinedin(3),(4)and(5),establishedlongtermmonitoringsitesforE. orramakunna, E.spinicaudatus, andE.yabbimunnawillcontinuetobesampledtoprovidebase-line information ontheirresponsestothreateningprocessesandvaryinglevelsofprotectionorremedial actionovertime.Continuedmonitoringofthesesiteswillrequirerelativelylittleinputintermsof resourcesortime.
TheidentificationoflongtermmonitoringsitesforE.martigenerneedstowaituntiltherangeofthe speciesisdeterminedandtypesofavailablesitesareknown(asper1.1above).Giventhecostof reachingfieldsitesonFlindersIsland,itispossiblethatanymonitoring maybeundertaken byfield staffontheisland,orthatmonitoringcanbeincorporated withinfuturefaunalconsiderations highlightedin the managementplanfor the park(ParksWildlifeService2000).Oneof the objectives oftheStrzeleckiNationalParkplanisto"protect,maintainandmonitorthreatened fauna species,inparticular theswiftparrot,burrowing crayfish,andNewHollandmouse...toprotect, maintainandmonitorthediversityofindigenousfaunaandhabitat...[and]tominimiseharmful impactsonindigenousfaunaandhabitats".OtherrelevantaspectsoftheStrzeleckiNationalPark managementplanincludepoliciesforthecontrolofwildfireandferalpigs.
Endangered SpeciesProgramfundsarerequiredtocoverthesalaryofaScientificOfficer,field assistance,equipment,travelallowancesandvehiclecosts.Contributions fromtheResource Management andConservation DivisionoftheDepartmentofPrimaryIndustries,Waterand Environment,andtheForestPracticesBoardareincluded.