!!!!!!! Quarterly!Update!!Kordofan!giraffe!(Giraffa& camelopardalis&antiquorum),!garamba!national!park,! Democratic!Republic!of!Congo!!

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1 QuarterlyUpdate Kordofangiraffe(Giraffa& camelopardalis&antiquorum),garambanationalpark, DemocraticRepublicofCongo JanuaryCMarch2017 MathiasD haen CzechUniversityofLifeSciences(CULS),Kamýcká961/129,16521Prague6HSuchdol,CzechRepublic Introduction GarambaNationalPark(GNP)intheDemocraticRepublicofCongo(DRC)wasfirstestablishedin 1938,oneofthefirstinAfrica,byvirtueofitsuniqueness.ThroughoutitslonghistorythePark was first made famous with the world s only elephant domestication program, coupled with its high numbers of elephant and buffalo, and home to the world s last northern white rhino (Ceratotherium+simum+cottoni)population.Additionally,theParkwasdesignatedaUNESCOWorld Heritagesitein1980andontheListofWorldHeritageinDangerin1996.Sadly,thePark sinfamy has increased through losing the last northern white rhino, and being plagued by numerous groupsofrebels,inparticularthelord sresistancearmy. In fact, the Park, being nestled in the far northheastern corner of the country, is writing history everydayagain,notbecauseofthecountries owndestabilisedpolitics(the2,000kmbetweenthe Parkandthecountries capitalcreatesanefficientbuffer),butbecauseofitswaragainstarmed militiacomingfromneighbouringcountries. GNP, and its adjacent Hunting Reserves, are also home to DRC s only population of giraffe, historically named Congo giraffe (Amube et al. 2009; De Merode et al. 2000; East 1999) but geneticallyidenticaltootherkordofangiraffeacrosscentralafrica(fennessyetal.2016). Duetoillegalhunting,currentgiraffenumbersintheParkandsurroundingareaswerereported to be less than 40 individuals and less than 2,000 Kordofan giraffe (Giraffa+ camelopardalis+ antiquorum)remaininthewild(mulleretal.2016).thenumbershaveneverbeensolowsince thefirstaerialcensusofgarambanationalparkwasundertakenin1976,when350giraffewere estimated(savidgeetal.1976). Interestingly, poaching of giraffe by local tribes living in the adjacent Hunting Reserves to GarambaNPhasbeenrelativelylimited.Thisisbecausetheybelievethatconsuminggiraffemeat causesleprosy.however,somegiraffewerepoachedinthelastdecadefortheirtailhairwhichisa status symbol for tribe chiefs (African Parks, 2012). Amube et al. (2009) reported that the traditional taboos have largely died out with the influence of modern society and the invading muharaleen+horsemen,whospecificallyvaluegiraffetailsaspartoftheirdowries,haveincreased 1

2 theirillegalhuntingofgiraffe.adeclineingeneralwildlifepopulationsintheparkisfurthermore linked to post war instability, power struggles and exploitation of resources, particularly from neighbouringcountries(hillmansmith&amube2005). ThegiraffepopulationoftheDRCwasformerlyrecognisedasaseparatetaxon,theCongogiraffe (G.+c.+congoensis),butnumerousauthorshavesincesubsumeditintoG.+c.+antiquorum,andmore recentlyasubspeciesofthenortherngiraffe(giraffa+camelopardalis)(fennessyetal.2016). Inthecontextoftheabove,theDRCInstitutCongolaispourlaconservationdelaNature(ICCN) andafricanparksnetworkhasbeenundertakingkeyconservationandmanagementofthepark, andmorerecentlyafocushasbeenonpreservingthelastremainingfew.gcfwithsupportfrom its partners has provided some technical and financial support to the Park, and the latest is through my conservation research efforts to assess the situation and to develop an adequate management plan for the remaining giraffe population. This quarterly conservation update providesanoverviewoftheworkundertakenfromjanuary March2017butisfollowingupona firstquarterlyupdatethatcoverstheworkundertakenintheperiodoctober December2016. Populationdynamics WiththedryseasonlastingfromDecember2016 March2017andfrequentfiresthatburnthe denselyhgrassed savannah, Garamba s wildlife has become easier to monitor. A lot of data was collectedduringthequarter,includingseveralnewgiraffeobserved. BeingdispersedoverfourdifferentregionsGaramba sgiraffearecategorizedintofourcategories (East, Northwest, Southwest and West). Besides two bigger populations in the East and Southwest,therearetwosmallpopulationsintheWestandNorthwest,hometo4and5giraffe respectively.oneothergiraffe(gir43f),whichwasfittedwithagpssatellitecollar,wasisolated from others but crossed back over the river during this Quarter and has since been seen with othergiraffe. Figure+2.+Population+dynamics+of+giraffe+in+Garamba+NP+categorised+by+region+observed+in.+ 2

3 3 Figure+3.+Satellite+image+of+Garamba+NP+containing+suitable+habitat+for+giraffe+and+bordered+all+ around+by+densely+wooded+areas.+ + The population dynamics of Garamba s giraffe arehighlightedbelow. The age class ratios are currently1:0.27:0.12(adult71.7%:subhadult19.6%:juvenile8.7%),whilethesexratiois1:0.67 (Female60%:Male40%),comparedtotheaverageof1:1(Female50%:Male50%). + + Figure+4.+Age+class+ratios+of+Garamba s+giraffe+compared+with+namibian+data+(fennessy,+2004).+ +

4 Figure+5.+Sex+Ratio+of+Garamba s+giraffe+compared+with+the+average+sex+ratio.+ Withtheknowledgethattherearetwentyadultfemalegiraffeinthepopulationandfemales usuallyconceivingbetween3h9monthsaftergivingbirth(foster&dagg1972;pellew1983b; Bercovitchetal.2006),wewouldexpectatheoretical offspringin2016/17(15months ofpregnancyplus3h9monthsforconceiving).onlyfivejuvenileswereobservedin2016,much lessthanexpected,possiblyexplainedbytworeasons.firstly,giraffecalvesmaysometimesdie beforetheyarebeingpickedupbytheteamassomeindividualsareonlyrarelyseen.secondly, adultfemalegiraffemaynotfallpregnantbecauseoflowpopulationdensitiesandhighly dispersedgroups. + Figure+6.+A+comparison+between+the+observed+and+a+theoretical+minimum+offspring+numbers+for with+20+adult+females+in+the+population.+ 4

5 Calculationofhomerangesandcorearea stoassesssuitabilityofhabitat In the SeptemberHDecember 2016 update I noted that Garamba consists of relatively nonhideal habitat, compared to other areas across Africa because of its low Acacia densities, playing an importantroleinagiraffe sdiet. Foodavailabilityisdirectlyrelatedtohomerangesize(Fennessy,2009),andgreaterwhenfood densitiesarelow.duringjanuaryandfebruary2015,eightgiraffewerefittedwithagpscollar (harnasstypesuppliedbyawttelemetry).datawastransmittedonanaverageof3h4timesper day, but fluctuated between weeks without any transmitted signal to a maximum of 586 data pointsonaday.allcollarshadadifferentlifespanwithonecollar,mwambe,currentlystillactive. Figure+7.+Table+highlighting+the+different+GPS+Satellite+collared+giraffe+and+associated+data.+ In calculating giraffehome ranges the Animove plugin for QGIS was used to estimate individual Minimum Convex Polygons (MCP) these highlight the amount of habitat they use over the analysedperiod.sincetheintervaloftransmittedcollardatawasirregular,alldatawasmanually processed. Processing consisted of standardising the interval between each two data points as muchastechnicallypossible,usuallyresultinginthreedatapointsperday. Asnotedbelow,threecollaredindividuals migrated duringtheperiodobserved.thesamewas notedforminei,anadultbullwho migrated towardsthemorewoodedregioneastofhisusual homerange mostlikelybecauseofthewoundhehassincebeenseenwith. Important to note that data from two of the giraffe are represented in the home ranges figures belowbuttheirdatanotusedincalculatingaveragesduetoinconsistencies.mwambe,anadult female,movedquicklyawayfromhercapturesiteandbecameisolatedfromothergiraffeonthe othersideofariverasitrose.whenthewaterleveldroppedagain,shemaderegularmigrations tootherpartsoftheparkbutfailedtoestablishastablehomerange.mostrecentlyshehasbeen seenwithothergiraffeintheregionwhereshewascollared.sambo,anadultfemale,ofwhichwe onlycollecteddataover51days,showedaverysmallhomerangecomparedtoothergiraffebut thedataislimited. 5

6 Figure8.HomerangevisualisationofthegiraffefittedwithGPSsatellitecollars 6

7 Figure9.HomerangeandcoreareawerecalculatedusingMinimumConvexPolygon(MCP). OutcomesforSamboandMwambewerenotusedincalculatingtheaverageduetolimiteddata. The preliminary average home range of the eight collared giraffe is km 2. On comparison withotherstudies(seetablebelow)weseethatthisisratherhigh. Mitano, an adult male, has a significant smaller home range compared to other giraffe. This is possibly because of the much more wooded area he lives in compared to those in much more sparsely wooded savannah. Another possible explanation could be that his home range is restrictedbecauseofthehumanactivitythatsurroundswhereheinhabits. Sincethereisacorrelationbetweenthehumidityofanenvironmentandtheexpansivenessofa homerange(dutoit1990;fennessy2009;lependu&ciofolo1999),homerangeisoftengreater in dryer areas. In Garamba NP one would expect to find smaller home ranges because of the abundanceofwater,however,theforagepreferenceforgiraffeissparselyspread.ifthedifferent study areas are compared with Africa s habitat and vegetation types(see below), much smaller home ranges are observed in other deciduous forestswoodland savannahs e.g. 68 km 2 for LuangwaValleyand7,09km 2 forrumanp,comparedtogarambanp. Gieling(2011)notedthatbesidestheavailabilityoffoodandwater,giraffe shomerangecanbe influencedbyotherfactorslikeclimate,topographyandthepresenceofherbivores,predatorsor humans (poaching, deforestation, fences). Therefore, one should be cautious as Garamba s relatively largehome ranges maybe due to limited food availability ashighlighted. Additionally, Garamba sherbivorepopulationshavedeclinedmarkedlyoveratleastthelastdecade.poaching isaknownseverethreattogiraffeintheparkwhilsttheimpactofpredationonthepopulation remainsunknown. 7

8 Figure10.LocationsofdifferenthomerangestudiesacrossvegetationzonesinAfricaincomparison withthoseingarambanp. Herdsize IntheSeptemberSDecember2016updateInotedthatGaramba sgiraffemayformsmallherdsto avoidbrowsingcompetitionandbecauseofthepark snonsidealhabitat,couldmakethemmore vulnerable to predation. This preliminary assumption needs to be seen in the context of the researchwhereananswertothequestion WhyisGaramba sgiraffepopulationsolow? isbeing sought. Theherdsizeaverageofthe1,043giraffeobservedin310herdsbetweenJune2014andFebruary 2017 is 3.36 individuals. Interestingly, of all observed herds, 95 (31%) consisted of single individuals(singletons).ifweleavetheseherdsoutofthedataset,theaverageherdsizeis:4.41. WhenwelookattheSouthwestpopulation,whoinhabitamuchmoreforestedarea,theaverage herdsizeismuchsmallerat2.55giraffe(n=49).incontrast,thegiraffetheeastwhichisamuch moretypicalgiraffehabitataveragehigherherdsizesof3.85giraffe(n=209). These numbers do not differ from known data in which herds tend to average 3S6 animals as observedbymanystudiese.g.innis1958;foster1966;leuthold1979;pratt&anderson1985;le Penduetal.2000;Bercovitch&Berry2009.Someoftheseauthorsalsoreportedthatgiraffeherds aresmallerinwoodlandandthicketareasthaninopenhabitats,regardlessofseason. To conclude, even though the Garamba NP data is based on a small dataset to date, it can be inferredthattheaverageherdsizeofgiraffeintheparkdonotdifferfromelsewhere.theaverage herd size of 3.36 is rather low and as such its giraffe might be more vulnerable to predation as 8

9 previouslythought.because of this, further research into the level of predation might help to understandifthisthreatbeanimportantfactorinthedeclineofthepopulation. MigrationsbygiraffeoftheEasternpopulationtowardstheWesternpopulation Except for normal intrashome range movements, three giraffe fitted with a GPS collar made a remarkable migration of ~50km towards the West away from their normal area. All three individualsmadethismigrationseparately,butthepatternswereverysimilarinallotheraspects. Migrationstookaboutoneweekintotalofwhich4S5dayswerespentontheactualtraveland2S3 dayswerespentinthewest.apartfromthethreegpscollaredgiraffeofwhichtheirmovements could be closely followed, other giraffe from the same region are known to make similar migrationstothewest. The reason for these migrations is still unknown but is possibly normal social behavior with giraffe in this region. It is not known whether giraffe of the Western population make similar migrationstowardstheeast.besidessocialbehavior,itcouldbethatthesemigrationsarebeing madetogivebirthtotheiryoung.gir05f,whohasalwaysbeenseenintheeast,wasseeninthe Westonlydaysbeforegivingbirthtoheroffspring.Afterwhichshewasseenmigratingbackto hernormalhomerangeintheeast. Acknowledgements I would like to thank DRC s ICCN and African Parks Network for their valuable support and development of this conservation research. I am especially grateful to Erik Mararv, Garamba s ParkManager,whotrustedmetoworkonthisproject,farbeforeIhaddeservedthistrust.AlsoI wouldliketothankkatespies,forhertime,helpfulcommentsandencouragements. Additionally, l would like to thank the Giraffe Conservation Foundation and their partners, AntwerpZooandZoodeLyon,forthevaluabletechnicalandfinancialsupportforthiswork. A huge appreciation goes to Julian Fennessy, who guided me in developing the project and on whoseexpertopinion,notonlyregardinggiraffe,butalsoacademicwriting,icouldcount. IwouldliketothankCzechUniversityofLifeSciencesforitsfinancialsupport,throughwhichI couldcovermytravelexpenses.lastly,iwouldliketothankkarolinabrandlova,forherpatience inrespondingonmypersistentquestionsregardingtheproject,aswellashervaluabletechnical support. Lastly,Iam very grateful for the financial support received from theruffordfoundation,which wasessentialtocovermyexpenses. Reference AfricanParks2012.FivegiraffesuccessfullycollaredinGaramba. parks.org/news_30_five+giraffe+successfully+collared+in+garamba.html(accessed24 January2016). AmubeNdey,J.,Antonínová,M.&HillmanSmith,K.2009.GiraffesoftheGarambaNationalPark, DemocraticRepublicofCongo.Giraffa3(1):8S10. Anyango,D.C.&WereSKogogo,P.J.A.2013.Movementpatternsandhomerangesizesofthe Rothschild sgiraffes(giraffacamelopardalisrothschildi)translocatedtorumanationalpark, Kenya.Int.J.Eng.Sci.2(3). 9

10 Bercovitch,F.&Berry,P.2009.EcologicaldeterminantsofherdsizeintheThornicroft sgiraffeof Zambia.BlackwellPublishingLtd.Afr.J.Ecol.48:962S971. Bercovitch,F.B.,Bashaw,M.J.&delCastillo,S.M.2006.Sociosexualbehavior,malematingtactics, andthereproductivecycleofgiraffegiraffacamelopardalis.horm.behav.50(2):314s321. Berry,P.S.M.1978.RangemovementsofgiraffeintheLuangwaValley,Zambia.Afr.J.Ecol.16:77S 83. DeMerode,E.,HillmanSmith,K.,Nicholas,A.,Ndey,A.&Likango,M.2000.Thespatialcorrelates ofwildlifedistributionaroundgarambanationalpark,democraticrepublicofthecongo. InternationalJournalofRemoteSensing21(14):2665S2683. DuToit,J.T.1990.FeedingheightstratificationamongAfricanbrowsingruminants.Afr.J.Ecol.28: 55S61. East,R.1999.AfricanAntelopeDatabase1998.IUCN/SSCAntelopeSpecialistGroup.IUCN,Gland, SwitzerlandandCambridge,UK. Fennessy,J.2004.EcologyofdesertSdwellinggiraffeGiraffacamelopardalisangolensisin northwesternnamibia.ph.d.thesis:universityofsydney. Fennessy,J.2009.HomerangeandseasonalmovementsofGiraffacamelopardalisangolensisin thenorthernnamibdesert.afr.j.ecol.47:318s327. Fennessy,J.,Bidon,T.,Reuss,F.,Kumar,V.,Elkan,P.,Nilsson,M.A.&Vamberger,M.2016.MultiS locusanalysesrevealfourgiraffespeciesinsteadofone.currentbiology26(18):2543s2549. Flanagan,S.,Brown,M.,Fennessy,J.andBolger,D.2016Useofhomerangebehaviourtoassess establishmentintranslocatedgiraffesafr.j.ecol.54(3):365s374 Foster,J.B.1966.ThegiraffeofNairobiNationalPark:homerange,sexratios,theherd,andfood.E Afr.Wildl.J.4:139S148 Foster,J.B.&Dagg,A.I.1972.Notesonthebiologyofthegiraffe.E.Afr.Wildl.J.10:1S16. Gieling,R.2011.Determinationofindividualhomerangesizeandgroupcompositionofthemain giraffepopulationatentabenigamereserve.masterthesis:utrechtunivsersity. HillmanSmith,K.&Ndey,J.A.2005.PostSwareffectsontherhinosandelephantsofGaramba NationalPark.Pachyderm39:106S110. Innis,A.C.1958.Thebehaviourofthegiraffe,Giraffacamelopardalis,intheeasternTransvaal.J. Zool.131:245S278. Langman,V.A.1973.RadioStrackinggiraffeforecologicalstudies.J.S.Afr.Wildl.Manage.Assoc.3: 75S78. Langman,V.A.1977.CowScalfrelationshipsingiraffe(Giraffacamelopardalisgiraffa).Z.Tierpsych. 43:264S286. LePendu,Y.&Ciofolo,I.1999.SeasonalmovementsofgiraffeinNiger.J.Trop.Ecol.15:341S353. LePendu,Y.,Ciofolo,I.&Gosser,A.2000.ThesocialorganizationofgiraffesinNiger.Afr.J.Ecol. 38(1):78S85. Leuthold,B.M.1979.SocialorganizationandbehaviourofgiraffeinTsavoEastNationalPark.Afr. J.Ecol.17:19S34. 10

11 Leuthold,B.M.&Leuthold,W.1978.EcologyofthegiraffeinTsavoEastNationalPark,Kenya.Afr. J.Ecol.16:1S20. McQualter,K.,Chase,M.,Fennessy,J.,McLeod,S.andLeggettK.2016.Homeranges,seasonal rangesanddailymovementsofgiraffe(giraffacamelopardalisgiraffa)innorthernbotswana, Afr.J.Ecol.54(1):99S102 MooreSBerger,E.1974.UtilizationoftheHabitatbytheReticulatedGiraffe(Giraffacamelopardalis reticulatalinnaeus)innorthernkenya.m.scthesis,universityofnairobi,kenya. Muller,Z.,Bercovitch,F.,Brand,R.,Brown,D.,Brown,M.,Bolger,D.,Carter,K.,Deacon,F.,Doherty, J.B.,Fennessy,J.,Fennessy,S.,Hussein,A.A.,Lee,D.,Marais,A.,Strauss,M.,Tutchings,A.&Wube, T Giraffa camelopardalis. The IUCN Red List of Threatened Species 2016: e.t9194a RLTS.T9194A en.Downloadedon13March2017. Pellew,R.A.1983.ThegiraffeanditsfoodresourceintheSerengeti.II.Responseofthegiraffe populationtochangesinthefoodsupply.afr.j.ecol.21:269s283. Pellew,R.A.1984.GiraffeandOkapi.In:TheEncyclopediaofMammals:2.(Ed.D.MACDONALD). GeorgeAllenandUnwin,London. Pratt,D.M.&Anderson,V.H.1985.Giraffesocialbehaviour.J.Nat.Hist.19:771S781. Savidge,J.,Woodford,M.&Croze,H.1976.ReportonaMissiontoZaireFAOW/K1593 KEN/71/526 ZAI/70/001. vanderjeugd,h.p.&prins,h.h.t.2000.movementsandgroupstructureofgiraffe(giraffa camelopardalis)inlakemanyaranationalpark,tanzania.j.zool.251:15s21. Vanderwaal,K.L.,Wang,H.,McCowan,B.,Fushing,H.&Isbell,L.A.2013.Multilevelsocial organizationandspaceuseinreticulatedgiraffe(giraffacamelopardalis).behav.ecol.25:17s