electrified fladry for deterrence of gray wolves (canis … · fladry shows great promise in...
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ELECTRIFIEDFLADRYfor
DETERRENCEOFGRAYWOLVES(CanisLupus)
AnEvolvingManualofBestPractices
By
StevePrimm,BryceAndrews,andAmyRobinson
© People and Carnivores 2018
Tom
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TableofContents
Introduction....................................................................................................................................................................1
Background......................................................................................................................................................................1
HowtoInstallFladry...................................................................................................................................................2 A. Spooling fladry ............................................................................................................................... 2
B. Carrying and driving posts .............................................................................................................. 4
C. Attaching fladry to the posts .......................................................................................................... 4
D. Anchor posts for applying tension or making corners .................................................................... 5
E. Maintaining consistent line height over rough terrain ................................................................... 7
F. Fladry gates .................................................................................................................................... 8
G. Electrifying ..................................................................................................................................... 9
LivestockContainment...........................................................................................................................................11
LiteratureCited...........................................................................................................................................................12
APPENDIXA–InstallationSummary(withIndex)..................................................................................13
APPENDIXB–ListofToolsandEquipmentNeeded................................................................................15
APPENDIXC:FladrySpoolerSpecifications................................................................................................17 Parts: ................................................................................................................................................. 22
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Introduction
Thismanualisforanyoneinstallingfladryorconsideringitsuseasaproactivecarnivoreconflictpreventiontool.TheoriginalmanualwaswrittenbyStevePrimmandBryceAndrewsofPeopleandCarnivores,anonprofitdedicatedtopreventinghuman-carnivoreconflicts,andAmyRobinsonoftheSunRanchInstitute.Throughadecadeofdeployingfladry,includingstretchesmorethanfourmilesinlength,wehavegarneredmanyimportantlessons.Wearecertainthatotherfladrypractitionershavemadesimilardiscoveriesandhavedevelopedusefultechniques.Inthefollowingpages,wehavedoneourbesttogiveaconcisesummaryofthepossibilities,challenges,andbestpracticesassociatedwithusingfladryinthefield.
Background
Therearemanytoolsforreducingwolfpredationonlivestock(Shivik2004).Amongthese,fladryshowsgreatpromiseinexcludingwolvesfrompastures.Anecdotalevidencefromfieldtrialsshowsthatfladrymaybeanineffectivedeterrentforgrizzlybears,mountainlions,andotherspecies.Assuch,thismanualreferstofladryasatoolforwolfdeterrencesinceithasbeentestedandusedforyearsforthispurpose.
Fladryconsistsofalineofcordagefromwhichflagsaresuspended.Fieldexperimentsdemonstratethatproperlydeployedfladrycanbeeffectiveforaslongas60days(Musianietal.2003).Electrifiedfladry—fladrycombinedwithsufficientelectricalcurrent—isevenmoreeffectivewhenproperlydeployed.Researchindicatesthatelectrifiedfladry(aka“turbofladry”)hasalongerdurationofeffectiveness(Lance2009).
Whileelectrifiedfladryhasthepotentialtobehighlyeffectiveinexcludingwolvesfrompastures,adoptionofthistoolremainslimited.Thereareseveralreasonsforthis:highcapitalcosts(approximately$2,600permileforfladry,excludinglabor,$600forenergizerwithbattery,and$400forposts);limitedavailabilityoffladry;andskepticismabouteffectiveness.
Fladrycanalsobedifficulttodeploywithoutproperequipmentandtraining.Becausetheflagscreatevoltageleakswhentheytouchotherobjects,apowerfulfencechargerisrequiredtokeepsufficientvoltageflowingthroughelectrifiedfladry.Topographyandotherparticularsofthesitemustalsobeconsidered,astheflagscanbecometangledinvegetationandfencesmakingthemineffectivedeterrents.
Despitethetool’ssteeplearningcurve,fladrycanbeaneffectiveandefficientstrategyforproactivelyaddressingpotentialwolfconflicts.Significantstrideshavebeenmadeinthepastdecadeintheapplication,installation,andbreakdownoffladrysystems.Whenfladrywasarelativelynewtechnology,deploymentwasextremelylaborintensive.Lance(2009)
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documentedlaborinputsofroughly32person-hoursperkilometeroffladry,orapproximately50person-hourspermile.Asamileoffladryisrequiredtosurrounda40-acrepasture—asizetypicallyusedforcalving—thelaborcosthashistoricallydrivenrancherstoabandonthetool.Today,however,fladrycanbedeployedatarateof7person-hourspermilewithappropriatetechnologyandatrainedcrewandcanbeuninstalledevenfaster.
Oncefladryhasbeenerected,itisessentialtokeepiteffectivelydeployed.Wind,precipitation,andungulatescancausefladrytosag,collapse,orbecomedismantled.Whiletherearemanysimilaritiesbetweenaconventionalpolywirefenceandelectrifiedfladry,theweightandwindresistanceoftheflagsthemselvesaddanewdimension.Iffladryistobeeffective,itmustbecheckedandmaintainedregularly.Suchmaintenance—whichtypicallyamountsto1person-hourperweekforafladryfenceingoodcondition—canbeintegratedintothedailyranchingroutine.
Afladryenclosureoftenfollowsthecontoursofanexistingpasture.Foruserconvenience,thefladrylinemustduplicateeverygateinanexistingpermanentpasturefence.Wheretheelectrifiedfladrylinecrossesexistingfencelines,caremustbetakentokeepthewiresproperlyinsulatedtoavoidvoltageshorts.
Whiletherearechallengestousingfladry,therearemanyanecdotalaccountsofitssuccessfuluse,aswellasstrongevidencegatheredfromfieldtrials.Wehaveutilizedfladryonmanyprojectswithnolosses,andhavefoundthetoolparticularlywellsuitedforuseincalvingpasturesorothersmall,high-riskgrazingunits.
HowtoInstallFladry
Inthissection,weprovideinstructionandphotosrelatedtothedeploymentandmaintenanceoffladry.Aswementionedintheintroduction,fladry’seffectivenessdependsonefficientandproperinstallation.
A.Spoolingfladry
Aftermultipledeployments,wehavetakenahardlookatwhatmakesfladry Figure 1: Hand coiling fladry is extremely inefficient.
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deploymentsopotentiallyinefficient.Withnumerousexperiencedworkers,werepeatedlyfoundthebiggesttimesinkwasindealingwithhand-coiledfladry.Evenwhenneatlycoiled,itisunwieldyandpronetotangling.Also,¼milecoiloffladry(1320feet)isfairlylong,somewhatheavy,andahandfulevenforpeoplewithlargehands.Thus,workersinevitablysetthecoilsdownortrytohangthemonfenceswhencarryingtheminthefield—anotheropportunityfortangling.
Mostprofessionalgraziersinsistonusingspoolsorreelsforhandlingtemporaryelectricfencewireinthepasturebecausetangleswastetimeandmakefenceconstructionunpredictableandinefficient.Addingflagstothepolywiremakesthetanglingproblemexponentiallyworse.Thus,wecannotstressenoughthatfladryneedstobespooledup.Fladryonaspoolhasgreatlyimprovedourefficiency,aswellasmakingfladryeasiertostore.
Otherusershavenotedthepotentialefficiencygainsofspoolingfladry,andhavedevelopedtheirownmethodsandequipment.Ourfladryspoolerisasimplemachinewithminimal
movingparts,andcanbeconstructedfromreadilyavailablepartswithnocustommachiningrequired.CompletedetailsandapartslistareavailableinAppendixA.Ourlargerspoolswillholdmorethan1½milesoffladry,dependingonhowtightlyitiswoundup.Wehavefoundthat1½milesoffladrymakesaveryheavyspool,sowegenerallylimitourquantitiestobetween½and1mileperspool.
Becauseofthebulkoftheflags,fladryrequiresafarlargerspoolthandoesbarepolywire.Therefore,whenconsideringaspoolingdevice,think
Figure 3: 1.5 miles of fladry on one spool.
Figure 2: Fladry spooler 2.0 in action.
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Figure 4: Golf bag filled with fladry posts; bag pockets can be used to store small parts.
big:6inchminimumbarespooldiameterand11inchminimumspoolwidth.Whiletherearemanyexcellentelectricfencereelsavailable,thesearegenerallytoosmalltoholdmorethanatrivialamountoffladry.
B.Carryinganddrivingposts
Aswithanytemporaryelectricfence,fladryneedstobeattachedtosomethingtokeepitatthecorrectheight.The
mostpopularandeconomicalchoiceis3/8inchx4-footfiberglassrodposts.Handlingdozensofthesepostsinthefield,whilealsowieldingahammertodrivethemintheground,canbechallenging.OneuniquesolutionwassuggestedtousbyaprofessionalgrazierinWyoming:useanoldgolfbag.Thefiberglasspostsslideintothegolfclubslots.Workerscanslingthebagacrosstheirtorso,allowingthemtocarryroughly40-50postshands-free.Havingbothhandsfreeallowstheworkertopullapostfromthebagwithonehand,positionit,andthentapitintoplacewithahammerintheotherhand.Thisdramaticallyshortensdeploymenttimeovercarryingthepostsinone’shands.
C.Attachingfladrytotheposts
Fiberglassposts—spacedroughly32feetapart,orsubstantiallycloserthanforbarepolywire—needsomesortofattachmentpointforjoiningfladrytopost.Aftermuchtrialanderror,wehavefoundoneproducttobefarsuperior:PremierFence’sHarpClip.TheHarpClipisdurable,stayswhereyouwantit,andallowsthefladryflagstoslidethroughratherthansnaggingwhentighteninguptheline.Clipsmadeofwirespringssnagtheflags.ClipsthatlooksimilartothePremierHarpCliphavenotperformedwellandtendedtocomeofftheposts.
TheHarpClipisalsowell-suitedtothegolfbagtechniquebecausetheclipscanbeleftonthepostswithnoriskofentanglingwitheach
Figure 5: Using a golf bag for posts leaves hands free for positioning and hammering posts.
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other.Thismakesstorageoflargequantitiesofpostseasieraswell.TheonlydifficultywiththeHarpClipsisthattheycanbedifficulttoinstallsincetheyaremadeofverystrongplastic.PremierFencehasrespondedbymakinganinexpensivetoolforsnappingtheclipsontothepost.
D.Anchorpostsforapplyingtensionormakingcorners
The3/8-inchfiberglasspostsarethemainstayofafladryline;however,theyarealsoveryflexibleandsmooth.Thus,whentryingtoaddtensiontoa
segmentoffladrysothelinedoesnotsag,wecannotrelyonthe3/8-inchpostsbythemselves.
Thesesmallerpostswillbendandwilleventuallypulloutofthegroundasweaddtensiontothefladry.Therefore,itisnecessarytoinstallheavierpostsatregularintervalsforaddingtensiontotheline.Weexperimentedwithnumerouswaysofdoingthisandwithdifferentspacingsandfoundthat,onrollingterrain,itwasnecessarytohaveaheavier,less-flexiblepostapproximatelyevery250feet.
SteelT-postsareoneoptionforheavyanchoringposts,astheyaredurableandreliable.Theyhavedrawbacks,however;theyweighalotandrequireapost-poundingdevicetoinstall,aswellasadeviceforremovingthemfromthegroundattheendofthedeployment.Inaddition,sincetheyaresteel,theyrequirecarefulattentiontoinsulationbecauseiftheelectrifiedfladrylinecontactsthesteel,itcreatesa“deadshort,”oracompletelossofvoltage.
WhilewestilluseT-postsinsomesituations,wehavefound
Figure 6: Premier Fence Harp Clip.
Figure 7: Steel T-post as an anchor for tensioning the fladry line in a fladry + polywire setup for dividing a cattle pasture. Note plastic insulators on post.
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betteralternativesfortensionanchors.Insituationswherethefladrylineparallelsapermanentfence,wefoundthatwecouldperiodicallytiethefladrylinetothepermanentpostsusingplasticinsulatorclipsandtwine.Theseanchorsprovedtobereliable,andthehardwarewasfarmoreportablethansteelT-postsandapounder.
OurpreferredmethodinvolvesDare-brandcornerinsulatorclipsand
alengthoftwine,withfencestaplesconnectingtoawoodenpost.TheDareclip(Part#BW-CP-10)provedtobeverydurableandveryaffordableatlessthan10centseach.
Wehavealsobegunusingavarietyofthicker/strongerfiberglassandcompositepostsforthesepurposes.UnlikesteelT-posts,thesepostsrequirenoinsulatorsastheydonotconductelectricity.CompositepostslikethePowerflexG2andPastureProhaveperformedthebest—theyarefairlyflexible,nearlyindestructible,andhaveenoughroughnessontheirsurfacetohelpthemstayintheground.Smoothfiberglasspostsmaypulloutofthegroundunderstrain(however,thismakesthemeasiertoremove).
Compositepostsrangeupto23/8inchesindiameterandarecomparableinpricetosteelposts.
Half-inchdiameterfiberglasspostsaresubstantiallystrongerand
Figure 8: Tensioning anchor, using a Dare-brand insulated clip and twine to connect the fladry line to a permanent post.
Figure 9: Powerflex composite post used to provide mid-line tension for fladry. Wire clip inserted through post keeps fladry at proper height; multiple half-hitches around the post vary the tension on the line.
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stifferthan3/8-inchdiameterandcanbeusedtomakeafladrysegmentmorerobustinchallengingconditions.
Forcreatinga90-degreecornerinafladryline,however,itisstillhardtobeatasteelT-post.Again,itisimperativethattheelectrifiedfladrylinenotmakeanycontactwiththepost.WehavefoundthattheDareclipanchoredtoaT-postmakesastrong,reliable,insulatedconnection.ThereareotherinsulatorsforT-posts,butwehavefounditpreferabletohavesomespacebetweenthelineandthesteel.
E.Maintainingconsistentlineheightoverroughterrain
Fladryflagsshouldbekeptslightlyabovethegroundwhenpossibletominimizevoltageleaksfromtheflags.Thelinemustnot,however,beraisedhigherthanabout28to30inches.Alinehigherthanroughly29inchesmayallowwolvestowalkunderthelinewithoutgettingshocked.
Onmanypastures,thefladrylinewillhavetocontouroverroughterrain,crossingditches,ravines,andotherfeatures.Keepingthefladrylineatafairlyconsistentheightinsuchplacescanbechallenging.Itispossibletousepoststokeepthelineatthedesiredheight,butinextremelyroughterrainthetensiononthelinemaybeenoughtouprootmostanypostsbesidesT-posts.Compoundingmatters,manyravinesanddrawsareextremelyrocky,
makingitdifficulttomanuallydriveT-postsorcompositepostsintotheground.
TheDarecornerinsulatorcliponceagainprovedveryusefulinsuchsituations.UsingtheDareclip,alengthofnyloncord(suchasparachutecord),andagood-sizedrock,weimproviseda“deadman”forholdingthelineparalleltotheterrain.
Again,thishastheadvantageofbeinghighlyportableandwithnoriskofshortsrelativetosteelposts.
Figure 10: Galvanized clip for half-inch fladry posts; this clip is very strong.
Figure 11: Dare clip deadman.
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F.Fladrygates
Anecessarypartofanyfladrydeployment,gatesarefairlysimpletoconstruct;theyjustrequireapairoffixedanchorposts,asdescribedabove,sothatadequatetensioncanbemaintainedacrossthegate.Itispossibleforoneendofthegatetobeanchoredtoapermanentfencepostnearthegate,butitisinadvisabletoputthegateoranyothersegmentoftheelectrifiedfladrylinewithinfladry-flag’slengthofthepermanentfenceduetoflagentanglementorelectricalshortrisk.
Thegatewayshouldbewiderthanthepermanentgateitparallels(Figure12).Thiswillallowplentyofroomformovingvehiclesandlivestockthroughthegate.Thefreeendofthefladrygateshouldbeonthesameendasthepermanentgatetofacilitateeasyuse.
Electricfencegatehandlesarerequiredhardwareforgateconstruction.Goodqualityhandlescostabout$4.00andarefarsuperiortothe$2.00varieties.
Cutthefladrylinewhereagateisrequiredandtietheendtotheeyeontheendofthegatehandle.Toensureagoodelectricalconnection,wrapthepolywiretwoorthreeturnsaroundthegatehandleeye,thentieitoffwithabowlineorothersuitableknot.Thegatehandle’shookend(thefreeend)willthenneedtobeconnectedtoananchorpostthatcanwithstandtension.
Figure 12: Fladry gate parallel to permanent gate. Both gates open from the right.
Figure 13: Gate handle connected to eye-bolt, attached to a Powerflex composite post.
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Wesuggestaminimumof7/8inchdiameterfiberglassorcompositepostsuchasthePowerflex1.6-inchcompositepost,withaholedrilledthroughtoacceptaneyebolt(Figure13).Thegatehandle’shookendthenclipsintotheeyebolt.Thefladrylinecontinuingfromthegatecanthenbetiedintotheeyebolt;again,makemultipleturnsaroundthemetaltoensuregoodconductivity.
Agateconnector,calledawood-postactivator,isanothergoodsolution.Thiscanbescrewedintoapermanentwoodpost.Ifusingthismethod,thefladrygatemustnotbecloselyparalleltothepermanentgate,butshouldintersectthefixedpostatananglethatkeepsmostofthefladrylineagooddistancefromthepermanentfence.Otherwise,theflagswilltangleinthepermanentfenceand/ortheelectrifiedfladrywillshortonthepermanentfence,renderingitineffective.
T-postsalsoworkforgates,butrequirereliableinsulation.Wehaveusedseveralinsulator/connectordevicesthatworkedwellonT-posts.ItisalsopossibletouseinsulatedfencewirewrappedaroundtheT-postasamakeshiftdeviceforconnectinggates.
G.Electrifying
Oncethevariouspostsandgatewayshavebeeninstalled,andtheelectrifiedfladrylinehasbeenattachedtothepostsandadequatelytensionedtopreventsagging,itistimetoaddtheelectricityitself.Thisisfairlystraightforward,andanygoodfenceenergizerwillincludeanillustratedmanualforproperinstallation.
Itisimportanttoselectagoodqualityfenceenergizerforelectrifyingfladry.Theflagsthemselvescreatesignificantvoltageleaks,especiallyiftheyareincontactwithvegetationortheground.Thus,electrifiedfladryrequiresasignificantlystrongerenergizerthananequivalentlengthofbarepolywire.
Thebaselinestrengthofelectricfenceenergizersismeasuredinjoules.Somemanufacturersreportstoredjoules,whileothersreportoutputorreleasedjoules.Themostimportantnumbertofocusonisoutputjoulesasaparameteroftheenergizer’sabilitytosupplyvoltageoverawiderangeofsituations.
Figure 14: Gate handle connected to a wood post activator/insulator.
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Basedonourmonitoringoffladryvoltagesinavarietyofsettings,webelievethatagoodgeneralguidelineisthatanenergizershouldhaveatleastone(1)jouleofoutputpermileoffladry.Wefoundthatanenergizerwith3-outputjoules(HorizontHotshockA50)withafullycharged12-voltbatterydeliveredconsistentvoltagesof4to5kilovoltsonmorethan3milesofelectrifiedfladry.Thiswasunderchallengingconditions,withthefladryincontactwithtallsagebrushandothervegetation.
Inadditiontotheguidelineof1outputjoule/mileoffladry,wealsorecommendaddingmoregroundrodstotheenergizerthanthemanufacturerspecifies.InthecaseoftheHotshockA50,Horizontrecommends6feetofgroundrod;weused3groundrods,3feeteach,foratotalof9feet.High-qualityrodsaremadeofeithercopperorgalvanizedsteel.
TheHorizontHotshockA50,aswellasafewotherenergizersfromHorizontandothermanufacturers(availablethroughPremierFence,e.g.),aretermed“wideimpedance”energizers.Wideimpedanceenergizersmaynothaveashighapeakvoltageasotherenergizers,buttheydeliverfarbetteraveragevoltageunderadverseconditions.SuchconditionsarefairlycommonintheIntermountainWestwhendealingwithwolves:
1. Dry,highmineralcontentsoilsthatdonotconductelectricitywell. 2. Drysnowincoldtemperaturesservingasinsulationfromelectricalshock. 3. Longfurinsulatingtheanimalagainstelectricshock(particularlyanissueinwinter
withwolves,especiallywhentheymaybestandingondrysnow).
Sincethesefactorsarefairlyroutinewhendealingwithwolves,wesuggestthatfladrypractitionersseriouslyconsiderusingonlywideimpedanceenergizers.
Otherpointstokeepinmindregardingelectricity:
Duringspringandsummergrowingseasons,itmaybeimpossibletokeeptheflagsfromtouchingvegetationbecausethegrassisgrowingsofast.Lineheightshouldbeadjustedasnecessary.
Figure 15: Horizont wide-impedance energizers with solar panels. The Hotshock B4 (left), with 0.35 output joules, is a compact unit that is suited for smaller runs of fladry around corrals or small pastures. The Hotshock A50 (right) is a heavy-duty unit that can adequately power more than 3 miles of electrified fladry; its 40-watt solar panel ensures a well-charged battery.
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Whensurroundingpastureswithpermanentfences,thefladrylineislikelytocrossoverorthroughexistingfencelines.Eachoftheseisapotentialshortthatmustbeinsulated.Shortrunsofinsulatingtubecanbemadefromrubbergardenhose(theblackheavy-dutyhose),whichcanbeslitlengthwisethentapedonwithelectricaltape.
Agoodvoltmeterisabsolutelyimperativeformonitoringenergizerperformanceandlocatingproblems.Accuratevoltmetersareavailableforlessthan$50;moresophisticatedmodelsthathelpfindshortsareroughly$120.
LivestockContainment
Thusfarwehavefocusedonfladryasawolfdeterrent.Clearly,incircumstanceswherethereisnopermanentfencecontainingthelivestock,ranchersandpractitionersneedtorelyonthefladryfencingforthispurpose.
Wehavefoundthatstandardelectrifiedfladrywasonlymarginallyeffectiveasalivestockfence.Thiswasbecauseflaglengthsof19inchesdictatedatopwireheightofnogreaterthan23inchesabovegrade(Davidson-NelsonandGehring2010).Inourprojects,wefoundthatcattlewouldoftenstepoverafencethatlow,whichfrequentlyledtobriefentanglementsthatresultedinlongstretchesoffladrybeingtorndownandrenderedineffective.
Weexperimentedwithlongerflagsthatwouldallowthetopelectrifiedwiretobeclosertotherecommendedcattlecontainmentheightof30to32inches.Afterdiscussionwithexpertsandextensiveresearch,wecouldfindnocompellingrationaleforflagsonly19incheslong.Wethink,however,thatthereisanupperlimitoneffectiveheightforfladry:toohigh,andwolveswouldfindittooeasytocrossundertheelectrifiedwirewithoutevermakingcontact.
Therefore,webelievethattheoptimaltopwireheightshouldcorrespondtowolfanatomicalparameters—thewireheightshouldbeslightlybelowaverageshoulderheightforawolf,orabout29to30inches.Webasethisontheideathatwolvesthatbegintolosetheirfearoffladrywillfirstexplorethenovelobjectwiththeirnoseandmouth.Canidswithacuriousattitudeoftenholdtheirheadslightlybelowshoulderheightastheyexplorenovelobjects.
Therefore,webelieve27inchesisthetheoreticaloptimumflaglength;thiswouldallowdeploymentofthetopwireatapproximately29to30inchesabovegradewithouttheflagsmakingexcessivegroundcontact(asignificantvoltagedrain).Preliminarytrialswithcattlehaveshownthat29inchesisaneffectivewireheightforcontainingadultcattle.
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LiteratureCited
Davidson-NelsonSJandGehringTM.2010.Testingfladryasanon-lethalmanagementtoolforwolvesandcoyotesinMichigan.Human-WildlifeInteractions4(1):87-94.
LanceNJ.2009.Applicationofelectrifiedfladrytodecreaseriskoflivestockdepredationbywolves(Canislupus).MSThesis,UtahStateUniversity,Logan.
LanceNJ,BreckSW,SimeC,CallahanP,ShivikJA.2010.Biological,technical,andsocialaspectsofapplyingelectrifiedfladryforlivestockprotectionfromwolves.WildlifeResearch37:708-14.
MusianiM,MamoC,BoitaniL,CallaghanC,GatesCC,MatteiL,VisalberghiE,BreckS,VolpiG.2003.WolfdepredationtrendsandtheuseoffladrybarrierstoprotectlivestockinwesternNorthAmerica.ConservationBiology17(6):1538-1547.
ShivikJA.2006.ToolsfortheEdge:What’snewforconservingcarnivores.BioScience56(3):253-59.
ShivikJA.2004.Non-lethalalternativesforpredationmanagement.Sheep&GoatResearchJournal19:64-71.
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APPENDIXA–InstallationSummary(withIndex)
Toinstallfladry:
Spooler–Spool.5to1mileoffladryonaspoolsothatit’snottooheavy(largerspoolscantake1.5milesoffladry,buttheyareheavy).Thespooleritselfmustbelargerthanwhatcanbeusedwithbarepolywire.pp3-5,andAppendixC(forspoolerassembly)
Postsandcarrying/drivingposts–Useanoldgolfbagorothercarryingbagthatallowstheworkertocarry40to50fiberglassposts(3/8inchx4feet)andbehands-free(topositionpostsandtapintoplace).p5.
Anchorpostsfortensionandcorners–The3/8-inchfiberglasspostscanpulloutwithtension,sowesuggestaddingheavier,lessflexiblepostsapproximatelyevery250feet.OptionsincludecompositepostssuchasPasturePro’s1.5”x5’linepost,steelT-posts,stronger/thickerfiberglassposts,ortyingthefladrytopermanentfence/postswithnon-conductivecord.pp6-8.
Tension–Itisbesttostretchthefladryinsegmentsoflessthan1/4mile,andtoapplytensionbeforeclippingittotheposts.Pullhardtoremoveallslackfromtheline,thensecurethefladrytothenearestheavypostorcorner.pp5-7.
Attachingfladrytoposts–Fladrylineneedstobeclippedtothefiberglassposts(3/8inchx4feet),whichshouldbespacedroughly32feetapart(closerthanforbarepolywire).ThebestproductforattachingfladrytoapostisPremierFence’sHarpClip.WealsorecommendusingPremier’sinexpensivetoolforsnappingtheclipsontotheposts.pp5-6.
Adjustingandmaintaininglineheight–Thefladrylinewillneedtocontourovertheterrain.Walkthelinetoensureconsistentheight.Fladryflagsmustbekeptfromleakingvoltagebytouchingtheground,vegetation,etc.,andthelineheightmustremaineffective(23-30”,dependingonthelengthofyourfladry,withflagshangingapproximately1-2”fromtheground.Werecommend27”flagswithalineheightof28-30”).Addextrapostswherenecessary,andconsiderusingtheDarecornerinsulatorcliptoimproviseadeadmantoholdthelineparalleltotheterrain.pp8-9.
Fladrygates–Anecessarypartoftheinstallation,gatesrequireapairoffixedanchorposts.Thegateshouldbewiderthananypermanentgateitmayparallel.Oneendofthefladrygatecanbeanchoredtoapermanentfence.Alsoneededareahandleandgateconnector.pp9-10.
Electrifying–Selectahighquality,strongfenceenergizer,asfladryflagsgeneratevoltageleaks.Themostimportantnumberisoutputjoules.Werecommendatleastone(1)jouleof
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outputperfladrymile.Wealsorecommendaddingmoregroundingrodstotheenergizerthanmanufacturerspecsdictate.Copperorgalvanizedsteelrodsworkwell.pp10-12.
Livestockcontainment–Thelineneedstobeneartheidealcattlecontainmentheightof30-32”butalsocorrespondtotheheightofwolfheadsandnoses(thelikelywaytheymightexplorethefence),about30”.Werecommendafladryflaglengthofabout27”,withthetoplineheightat29-30”.p12.
Testing–Useavoltmetertomeasurethevoltageofthefence.4,000-5,000voltsisanacceptablereading,buthigherreadings(upto10,000volts)arepreferable.p11.
Communication–Talkwiththelandownerandanyimmediateneighborstoletthemknowthatyouhaveinstalledanelectricfence.Considerhangingaplasticwarningsignonornearthefladrylinetoavoidaccidents.
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APPENDIXB–ListofToolsandEquipmentNeeded
• Sufficientfladrytoenclosethepasture
• Line,corner,andtensioningposts
• Fenceenergizercapableofdeliveringoneoutputjoulepermileoffladry
• Groundrodsforenergizerandlightningbrake
• Insulatedwiretoconnectchargertofence
• Uninsulatedwireorbraidedaircraftcabletoconnectchargertogroundfield
• Lightningdiverterorbrake
• Fladryspooler
• Deadblowhammerorcapfordrivingfiberglasslineposts
• PounderforT-Postsandlarger-diametercompositeposts
• Sledgehammerfordrivinggroundrods
• Utilityknifeforcuttingandsplicingwire
• Splitboltsforelectricalconnections
• Nonconductivecord
• Spareharpclips
• Cornerclips
• Pinlockplasticinsulators
• Cotterpinsforcompositeposts
• Drillanddrillbits
• Screws
• Fencestaples
• Endstraininsulators
• Deadendgatehandles
• Passthrough(conductive)gatehandles
• Voltmeter/faultfinder
• Leatherorrubber-palmedglovesforhandlingfiberglassposts
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APPENDIXC:FladrySpoolerSpecifications
Our fladry spooler has gone through a few iterations, finally evolving into a simple machine that can be
constructed with minimal welding and pre-fabricated parts. The basic design is for a hand-cranked
machine that fits into the hitch receiver on a vehicle; the design can be readily modified to make the
spooler freestanding or attachable to an ATV rack. To increase the spooler’s versatility, we designed it to
use easily interchangeable spools, as well as to use a variety of different spools to suit user needs.
Our original design aim was to make the spooler collapsible into four main parts. However, as the design
grew simpler, we realize now that the spooler can be built to have just two major components: the
frame, and a detachable axle (or spindle) for holding the spool. This keeps the spooler lightweight and
with fewer parts to lose.
The spooler frame is made of steel tubing; we used 2”x2”x0.25” for the horizontal piece that inserts into
the vehicle’s hitch receiver. The angled arm piece is 2”x2”x0.188”; this lighter tubing saves weight, and
Figure A: Spooler 2.0, which included a level-winding device to evenly distribute the fladry on the spool. The level winder has been omitted from subsequent designs.
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allows “telescopic” assembly by accommodating 1.5”x1.5” tubing if the spooler is made to be
collapsible. We set the arm at a 65° angle from horizontal.
The next piece is the 3”x2”x0.188” rectangular tube to support the spindle and spool. This material can
be welded directly to the angled arm; or it can be welded to 1.5” square tubing if collapsibility is desired.
We made this piece 10” long.
Figure B: Spooler specifications. The frame can be built in one piece instead of two, if desired.
B
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At 8.5”, we cut a through-hole into the 3”x2” tubing; this hole is to accommodate a pipe coupling. We
used a forged pipe coupling for durability, and selected one threaded for 1.5” nominal pipe diameter.
This size allows flexibility in choosing spools, since reducing bushings can be threaded into the coupling
to accommodate smaller diameter pipes as
spindles.
The pipe coupling can be accessed from
either side of the frame. This allows the user
to put the spindle on either side, or to run
two spools at once if necessary.
Spindles or axles can be made from
whatever shaft material the user desires.
However, we found that pre-cut, pre-
threaded galvanized pipe made suitable
spindles with sufficient strength, even under
demanding loads over rough terrain.
Threaded on both ends, the pipes easily
threaded into the coupling on the spooler
frame, and allowed use of a floor flange to
keep the spool on the spindle in the field.
Figure C: Pipe coupling detail; coupling can be accessed from either side of frame for versatility.
Figure D: Top view of pipe coupling welded into 3x2 tube; note reducing bushing on right receiving 1" pipe as spindle.
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We found that McMaster-Carr polyethylene spools were affordable, durable, and lightweight. The size
that has worked best for us was a 17” wide by 6” diameter spool core, with 24” flanges. This spool was
large enough for over a mile of fladry if wound tightly.
The diameter of the hole on the spool core is
1.5”, which is larger than the outside
diameter of 1” nominal pipe and smaller
than the outside diameter of 1.5” nominal
pipe. Thus, it may be a good idea to use a
bushing of some sort on the pipe spindle.
Bushings make the spool rotate far
smoother and easier, and also minimize
wear on the spool.
We used bronze bushings
(sleeve bearings) from
McMaster-Carr. There was no
size available to precisely fit
both the spindle and the spool.
McMaster-Carr part # 6381K271
was a close fit, requiring minor
reaming to fit the bushing onto
the pipe. Users may find this
bearing may require a slight
reduction in outside diameter to
fit the spool, but the
polyethylene is flexible enough
to slide onto the bearing with no
modification in most cases.
Bushings can be fixed in place on
the spindle with a small welded
bead or adhesives.
Figure E: Polyethylene spool from McMaster-Carr; note detachable handle on flange.
Figure F: 1" nominal pipe spindle, with bronze bushings for smooth spool rotation. Three bushings to accommodate different size spools.
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The spools need handles for the user to wind up fladry. McMaster-Carr has handle assemblies that work
well. We chose rotating plastic handles that can be bolted to and easily removed from the spool flanges.
This eliminates the need to have a
handle for every spool, and allows
spools to be easily stacked for
storage.
The handle has a threaded stud;
we used a coupling nut and a
wide-head bolt to attach the
handle to the spool flange. A
reinforcing spacer of metal or
plastic on the inside of the flange
is optional, but should increase
flange durability.
Figure G: Removable spool handle attached to flange.
Figure H: Handle removed from spool; note coupling nut & bolt.
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Parts:
1) Forged pipe coupling, McMaster-Carr part number 7739K148
2) Reducing bushing, McMaster-Carr part number 4638K572; also widely available at hardware and plumbing stores.
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3) Bronze (alloy 932; cleaner than Oillite) bushings, McMaster-Carr part number 6381K271
Outside diameter: 1 5/8” Inside diameter: 1 5/16” Length: 2.5”
4) Floor flange; this item should be purchased at hardware or plumbing store.
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5) Tapered, rotating handle, McMaster-Carr part number 6308K46
6) Coupling nut 1.75” length, for handle; 1/2"-13 thread; McMaster-Carr part number 90977A195.
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7) Bolt 1” length, ½”-13 thread; for attaching coupling nut/handle assembly through spool flange; McMaster Carr part number 91255A712 button head socket-cap bolt. This bolt has a low-profile
head so it doesn’t snag fladry. Uses a 5/16” Allen wrench to attach or remove the handle.
8) Components for Polyethylene spools a. 17” spool core, McMaster-Carr part number 38305T12 b. 24” spool flanges, McMaster-Carr part number 38305T23