Plumptre, A.J., T.R.B. Davenport, M. Behangana, R. Kityo, G. Eilu, P. Ssegawa, C. Ewango, D. Meirte

17 Pages·2006·0.64 MB·English

BIOLOGICAL CONSERVATION 134 (2007) 178–194
available at www.sciencedirect.com
journal homepage: www.elsevier.com/locate/biocon
The biodiversity of the Albertine Rift
Andrew J. Plumptrea,*, Tim R.B. Davenportb, Mathias Behanganac, Robert Kityoc,
Gerald Eiluc, Paul Ssegawac, Corneille Ewangoa, Danny Meirted, Charles Kahindoc,
Marc Herremansd,k, Julian Kerbis Peterhanse,f, John D. Pilgrimg,l, Malcolm Wilsonh,
Marc Languyi, David Moyerj
aWildlifeConservationSociety,P.O.Box7487,Kampala,Uganda
bWildlifeConservationSociety,P.O.Box1475,Mbeya,Tanzania
cMakerereUniversity,P.O.Box7062,Kampala,Uganda
dRoyalMuseumforCentralAfricaatTervuren,Leuvensesteenweg11,3080Tervuren,Belgium
eRooseveltUniversity,UniversityCollege,430SMichiganAvenue,Chicago,IL60605,USA
fFieldMuseumofNaturalHistory,Chicago,1400S.LakeShoreDrive,Chicago,IL60605-2496,USA
gCenterforAppliedBiodiversityScience,ConservationInternational,1919MStreetNW,Suite600,Washington,DC20036,USA
hP.O.Box178,Groblersdal0470,Mpumalanga,SouthAfrica
iWWFEasternAfricaRegionalProgrammeOffice(EARPO),P.O.Box62440,00200Nairobi,Kenya
jWildlifeConservationSociety,P.O.Box936,Iringa,Tanzania
kNatuurpunt.Studie,Coxiestraat11,2800Mechelen,Belgium
lBirdLifeInternationalinIndochina,4/209DoiCan,BaDinh,Hanoi,Vietnam
A R T I C L E I N F O A B S T R A C T
Articlehistory: TheAlbertineRiftisoneofthemostimportantregionsforconservationinAfrica.Itcon-
Received16June2005 tainsmorevertebratespeciesthananyotherregiononthecontinentandcontainsmore
Receivedinrevisedform endemicspeciesofvertebratethananyotherregiononmainlandAfrica.Thispapercom-
17July2006 piles all currently known species distribution information for plants, endemic butterfly
Accepted8August2006 speciesandfourvertebratetaxafromtheAlbertineRift.Theliteratureonfishspeciesrich-
Availableonline14November2006 nessandendemismisalsoreviewedtoassesstheimportanceofthelargerlakesintheRift
forconservation.Weusedatafrom38protectedandunprotectedareastoprioritisesites
Keywords: withintheAlbertineRiftforconservationbasedupontheirnumbersofendemicandglob-
AlbertineRift allythreatenedspecies.VirungaandKahuziBiegaNationalParksandItombweMassifin
Prioritysetting DemocraticRepublicofCongo,BwindiImpenetrableandKibaleNationalParksinUganda,
Mammals andNyungweNationalParkinRwandarankhighestintermsofnumbersofbothendemic
Birds and globally threatened species. Six conservation landscapes are described that include
Reptiles mostofthesesitesanditisarguedthatafocusontheselandscapesmaybeamoreholistic
Amphibians methodtoensurethesafetyofthepriorityareasoftheAlbertineRift.
Plants (cid:2)2006ElsevierLtd.Allrightsreserved.
Biodiversity
1. Introduction etal.,2003).ThispartofAfricacontainsthe‘Mountainsofthe
Moon’orRwenzoriMassifthatincludesAfrica’sthirdhighest
The Albertine Rift is the most species rich region for verte- peak, the Virunga Volcanoes made famous by its mountain
bratesontheAfricancontinent(Brooksetal.,2001;Plumptre gorillas, active volcanoes in the Virunga National Park, and
* Correspondingauthor.
E-mailaddress:[email protected](A.J.Plumptre).
0006-3207/$-seefrontmatter (cid:2)2006ElsevierLtd.Allrightsreserved.
doi:10.1016/j.biocon.2006.08.021
BIOLOGICAL CONSERVATION 134 (2007) 178–194 179
Lake Tanganyika – Africa’s deepest lake. The Albertine Rift FosseyGorillaFundInternational,InstituteforTropicalForest
encompassesmuchofthewesternRiftvalleydowntosouth- Conservation,InternationalGorillaConservationProgramme,
ernTanzaniaandnorthernZambia.Wedefinetheregionas MakerereUniversityInstituteofEnvironmentandNaturalRe-
extending from 30km north of Lake Albert to the southern sources,WildlifeConservationSociety(WCS)andWWF.The
tip of Lake Tanganyika, including the valley, flanks of the compilation of the biodiversity information was one aspect
escarpment and associated protected areas, and the range ofthisplanningprocessandwasledbyWCS.Thispaperad-
ofspeciesendemictoit(Plumptreetal.,2003).Variousother vancesthis collaborative effortbyusingthecollateddatato
publicationsalsorecognizethe‘AlbertineRift’(Poulsen,1997; prioritisesitesintheAlbertineRiftforconservationaccording
Prigogine,1985):itisanEndemicBirdAreaaccordingtoBird- totheirnumbersofendemicandgloballythreatenedspecies.
Life International (Stattersfield et al., 1998), WWF have de-
fined it as a ‘Global-200’ priority ecoregion (Olson and 1.1. TheAlbertineRiftregion
Dinerstein,1998;Burgessetal.,2004),andConservationInter-
national(CI)hasrecognizeditaspartoftheEasternAfromon- As part of this planning process a series of meetings were
tane Hotspot in their second global analysis (Brooks et al., heldbetweenFebruary2001andMarch2003,whentheframe-
2004).ThereismuchoverlapinthedefinitionoftheAlbertine workwasfinallydeveloped.Duringthisprocessitwasagreed
Riftbetweenthesepublications,butalsosomedifferencesin thatthedefinitionoftheAlbertineRiftshouldbeasinclusive
geographicalcoverageaseachanalysishasuseddifferentcri- aspossibleforthemomentsothatovertimeitcouldbere-
teria to delineate the region. WWF’s Ecoregion focuses pri- fined (Plumptre et al., 2003). The current adopted definition
marily on the montane forests and separates moorland thereforeincludesallthenaturalhabitatswithin100kmeast
from these forests, while BirdLife International’s Endemic oftheborderofDemocraticRepublicofCongo(DRC)andfol-
birdareaisbroaderandincludesthemoorlandsandhighland lowsthe900mcontourlineineasternDRC,includingthepro-
swamps. CI’s Eastern Afromontane Hotspot is broader still tected areas in northern Zambia (Fig. 1). The 900m contour
and includes the definition of the Albertine Rift used here was selected because there are museum collections at the
(seebelow). RoyalMuseumforCentralAfricainTervuren,Belgium,ofAlb-
TheAlbertineRiftisnotonlyimportantforitsbiodiversity ertineRiftendemicbirdspeciesthatwerefoundaslowasthis
butalsoforitsecologicalprocessesandecosystemservices. altitude.
Thesavannaparkscontainedsomeofthehighestbiomasses The total area encompassed is around 313,000km2
oflargemammalsrecordedonearthinthe1960s(Cornetd’Elz- (Plumptre et al., 2003). The habitats range from the glaciers
ius,1996).Warandpoachinghaveledtomajordecreasesinthe and rock at the top of the Rwenzori mountains (5100m),
numbersoflargemammalsintheseparksbutmostofthespe- down through alpine moorland (3400–4500m), Giant Senecio
ciesarestillpresentandcouldrecovertoformerlevelswith
good protection (Plumptre et al., 2007). The impacts of the
browsingandgrazingoftheelephants,hippopotamuses,buf-
falos,andantelopespecieshadamajorinfluenceonthevege-
tationoftheparks(Delvingt,1978)andasaresultofthedecline
innumbersofthesespeciesitisthoughttheparksarechanging
(Eltringham,1999).ThevolcanoesintheVirungaNationalPark
areactiveandinfluencetheecologyofalargeportionofthis
parkanditssurroundings.Thefisheriesinsomeofthelakes
arethemostproductiveonthecontinentandprovidealiveli-
hoodformanypeople(Beadle,1974;Snoeks,2000)andtheriv-
ers and streams flowing from the forests on the mountains
providecleanwater.InRwanda,forexample,itisestimated
thatmorethan70%ofpeopleobtainwaterthatcomesfrom
theirnationalparks(Weber,1989).Thespectacularlandforma-
tionsandrichbiodiversityoftheAlbertineRiftmeanthatithas
greatpotentialfortourism.Civilwarsandinternationalcon-
flictoverthepast30yearshavehamperedtourismdevelop-
mentbutwhenpeacecomestotheregionthereisenormous
potentialtodevelopworldclasstourism.
Thispapersummarisestheexistingliteratureonbiodiver-
sitysurveyswithinsitesintheAlbertineRift.Itistheresultof
a collaborative effort between many different NGOs, pro-
tectedareaauthoritiesand museumsthathaveinformation
about this region. Since 2001 the protected area authorities
and their NGO partners have been developing a strategic
frameworkforconservationintheAlbertineRift.Atthistime Fig.1–MapoftheextentoftheAlbertineRiftasconsidered
acoreplanninggroupwasestablished,whichdevelopedthe here.Forestedprotectedareas(orsurveyedareas)arein
strategic framework for conservation in the Albertine Rift, darkgrey,savanna/miombowoodlandprotectedareasare
that includes the Albertine Rift Conservation Society, Dian inlightergrey.
180 BIOLOGICAL CONSERVATION 134 (2007) 178–194
and Lobelia vegetation (3100–3600m), giant heather (3000– et al. (1987). A list for the Virunga Volcanoes was produced
3500m), raised bogs (3000–4000m), bamboo forest (2500– using de Witte (1938), Wilson (1995) and Hutterer et al.
3000m), montane forest (1500–2500m), to lowland forest (1987).ForDRC,deWitte(1938)reportedonextensivesurveys
(600–1500m), savanna woodland (600–2500m) and savanna by Belgian scientists in the Virunga National Park. Muhlen-
grassland(600–2500m).PapyrusandCarexwetlands,together bergetal.(undated)providedalistforKahuziBiegaNational
withlakesandstreams,havetheirownuniquehabitattypes ParkandOmarietal.(1999)providedalistforItombweMas-
varying from the rocky and sandy edges to the benthic and sif. For Burundi, a listwasobtainedforKibiraNational Park
bathypelagic zones in the depths of the lakes. Several very (FieldMuseum,Chicago(KerbisPeterhans,inlitt.,FMNHdata-
specialised habitats also occur as a result of the volcanic base,Chicago),PeaceCorpsandINECN(undated).ForTanza-
activity in the Virunga National Park, including lava flows nia,listswereobtainedforGombefromtheGombeNational
and their associated colonising vegetation, hot springs and Parkwebsite,forMahalefromAnonymous(1985)andforMbizi
speciesadaptedtocarbonmonoxideandmethane. fromD.MoyerandW.Stanley’ssurveys.ForZambia,listsfor
Sumbu and Mweru-Wantipa National Parks were generated
2. Methods fromthedistributionrecordsgivenbyAnsell(1978).
2.1. BiodiversityoftheAlbertineRift 2.1.2. Birds
ThemainsourceforUgandawasthechecklistofbirdsofthe
InitiallyWCScompiledlistsofspeciesfromexistingliterature national parks (Wilson, 1995) and the biological surveys
and by working with researchers at Makerere University, undertaken by the Uganda Forest Department (Howard and
Uganda. Much of the literature was in unpublished reports Davenport,1996–whichalsocompileddatafrommanypre-
or‘greyliterature’.Dataonmammals,birds,reptiles,amphib- viously published sources). Additional data came from the
ians, butterflies and plants were compiled, and information Enhancement of Research Capacity (ENRECA) project man-
on some museum specimens collated with the help of mu- aged by Makerere University Institute of Environment and
seum experts (Royal Museum for Central Africa, Tervuren, NaturalResources,surveysundertakenbyWCS,andrecords
Belgium; Missouri Botanical Gardens, USA; Field Museum, compiled by Malcolm Wilson. Additional published records
Chicago, USA, and Royal BotanicGardens,Kew, UK)from 38 thatwereincorporatedafterexpertpeerreviewincludeEvans
siteswithintheAlbertineRift(Fig.2).Wealsoreviewedthelit- and Balmford (1992), Gnoske and Marks (1997), Kalina and
erature for fish species totals as it was recognized that the Butynski (1996), Friedmann and Williams (1970), Dehn and
lakesintheAlbertineRiftregionarealsoimportantforcon- Christiansen(2001), Stubblefield(1993), and Allan (1994).For
servation. We attempted to compile information from as Rwanda,KunkelandKunkel(1969),Dowsettetal.(undated),
manyareas oftheAlbertineRiftaspossible.Dataon collec- Dowsett (1990) and Plumptre et al. (2002) produced lists of
tions of amphibians and reptiles from the Royal Museum birdsfortheNyungweForestReserve.Thesedatawerecom-
forCentralAfricaallowedsomeanalysistobemadeofspe- bined with unpublished sightings from the WCS project in
ciesoutsideprotectedareas.Datafromplantfamilydescrip- this forest. A list for the Virunga Volcanoes was produced
tionsandherbariawerealsousedtogenerateapreliminary using Schouteden (1938), Wilson (1982), and Wilson (1995).
list of endemic plant species, many of which are not found Schouteden (1938) reported on extensive surveys by Belgian
inthesitesselectedhere.Notsurprisingly,however,mostof scientistsintheVirungaNationalParkinDRCandVerheyen
thesitesselectedwereprotectedareasasthatiswheremost (1947)addedspeciestothenorthernpartofthepark.M.Lan-
surveyshavebeenmadeintheAlbertineRift.However,some guyprovidedadditionalobservations.Muhlenbergetal.(un-
unprotectedareasalsohadsurveyinformation,includingthe dated) and Wilson and Catsis (1990) provided a preliminary
ItombweMassif,MarunguMassif,highaltitudeareaswestof list for Kahuzi Biega National Park and thiswas augmented
LakeEdwardandMtKaboboaswellasareasaroundMahale by M. Herremans using the database of bird specimens at
MountainsNationalPark.WhilenotcoveringthewholeAlber- theRoyalMuseumforCentralAfricainTervuren.Schouteden
tineRift,thesesitesdoincludethelargerprotectedareasand (1949) surveyed Katanga district from which a list for Mar-
thelargestareasofunprotectedhabitat. unguMassifwasderived,Prigogine (1960)providedalistfor
Themainsourcesusedforeachtaxonwereasfollows: Mt Kabobo, Prigogine (1971–1984), Wilson and Catsis (1990)
and Omari et al. (1999) provided lists for Itombwe Massif
2.1.1. Mammals and Prigogine also provided lists for Idjwi Island (Prigogine,
ThemainsourceforUgandawasthechecklistofmammalsof 1967)andfortheareawestofLakeEdward(Prigogine,1953).
thenationalparks(Wilson,1995)andthesmallmammalsur- ManynewrecordsineasternDRChavebeenpublishedbyDe-
veys undertaken by the Uganda Forest Department(Howard mey et al. (2000). Tom Butynski contributed records for Mt
and Davenport, 1996). Additional data for large mammals Tshiaberimu. Schouteden (1966) published a list of birds of
camefromKingdon(1971–1983)andforsmallmammalsfrom Burundi with locations where they had been sighted – this
Kerbis Peterhans et al. (1996), Kerbis Peterhans and Austin publication was used to compile a list for Ruzizi National
(1996),KerbisPeterhans(1997)andvanderStraetenandKer- Park.Gaugrisetal.(1981)addedspeciestothislistandINECN
bisPeterhans(1999).Dowsett(1990)producedalistofmam- producedalistforKibiraNationalParkinthemid1980s(IN-
mals for the Nyungwe Forest Reserve in Rwanda and this ECN, undated). van de Weghe and Loiselle (1987) also pro-
wascombinedwithunpublishedsightingsfromtheWildlife duced a list for Bururi forest reserve. Neil Baker provided
ConservationSocietyprojectinthisforestandfromHutterer listsforGombeStreamandMahaleMountainsNationalParks
BIOLOGICAL CONSERVATION 134 (2007) 178–194 181
Fig.2–Thenorthern(a),central(b)andsouthern(c)portionsoftheAlbertineRiftshowingthelocationsofthevarious
protectedareas(NP=nationalpark;FR=forestreserve;WR=wildlifereserve)orungazettedareaswithspeciesdata(no
suffix).Darkershadedareasareforestedandlighterareasaresavannagrasslandorwoodland.
from the Tanzania Bird Atlas database. These were used to getheralistforKibaleNationalPark.Spawlsetal.(2002)iden-
correct and add to lists compiled by Stanford and Msuya tify localities for species for East Africa using general maps
(1995), Ulfstrand and Lamprey (1960), and Moreau (1943). D. and these were used to assign species to a site if this was
MoyerprovidedlistsforMbiziforest. either mentioned in the text or if the map distribution was
unequivocal. M. Behangana, from recent surveys, provided
2.1.3. Reptiles severalrecords.HinkelandFischer(1988)wasusedtodevelop
Pitman(1938,1974)wasusedasastartingpointforreptilesin alistofspeciesforVirungavolcanoesandNyungweforestin
Uganda.DrewesandVindum(1998)providedaspecieslistfor Rwanda.ThiswasaugmentedbydeWitte(1941)fortheViru-
BwindiImpenetrableNationalParkandVonesh(1998)putto- nga volcanoes. Dowsett (1990) also provided a list for
182 BIOLOGICAL CONSERVATION 134 (2007) 178–194
Nyungwe Forest. D. Meirte extracted lists of specimen loca- Maramagambo forests. Synnott (1985) provided a checklist
tionsfromthedatabaseattheRoyalMuseumforCentralAfri- ofplantsforBudongoForestReserve.ForRwanda,plantspe-
ca in Tervuren. For DRC, de Witte (1941) produced a list of cieslistsfortheVirungaVolcanoeswereobtainedfromBurtt
reptiles for Virunga National Park and mapped the distribu- (1934),Robyns(1948–1955),Troupin(1978–1988),andtheher-
tionsofchameleonsincentralAfrica(deWitte,1965).D.Mei- barium at the Karisoke Research Station. Plant species for
rteextractedlistsofspecimenlocationsfromthedatabaseat Nyungwe were compiled from Robyns (1948–1955), Troupin
theRoyalMuseumofCentralAfricainTervuren.Onlylimited (1992),Plumptreetal.(2002)andtheherbariumattheProject
datawereobtainedforBurundi.Spawlsetal.(2002)wasused Conservation de la Foreˆt de Nyungwe. Robyns (1948–1955)
tocompilealistofreptilesforGombeandMahaleMountains providedarelativelycompletelistforVirungaNationalPark
ParksinTanzania. inDRCandFischer(1996)providedalistforKahuziBiegaNa-
tionalPark.NoplantlistswereobtainedforsitesinBurundi.
2.1.4. Amphibians ForTanzania,thelistofplantsofGombewasprovidedbyRoy
DrewesandVindum(1994,1998)andDrewesetal.(1992)pro- Gereaufromhissurveysthere.ToshisadaNishidakindlypro-
vided a species list for Bwindi Impenetrable National Park videdalistofplantseatenbychimpanzeesforMahaleMoun-
andVonesh(1998)puttogetheralistforKibaleNationalPark tains National Park. Additional species for Mahale were
inUganda.ManyrecordswereprovidedbyM.Behanganafrom obtained from Vollesen and Bidgood (1996, 1999). A species
recentsurveys.InRwanda,HinkelandFischer(1988)wasused listforMbiziforestwascompiledfromMwasumbi(2000).Leb-
todevelopalistofspeciesforVirungavolcanoesandNyungwe runandStork(1991–1997)wasusedtocorrectsynonymstoa
forest.ThiswasaugmentedbydeWitte(1941)fortheVirunga standardisedlistofnames.
volcanoes.Dowsett(1990)alsoprovidedalistforNyungweFor-
est.ForDRC,deWitte(1941)producedalistofamphibiansfor 2.1.7. Datacleaningandidentificationofspeciesof
VirungaNationalParkbuttheidentificationsneededupdating. conservationconcern
ThedatabaseattheAfricaMuseuminTervurenisinthepro- Aftersixmonthsofdevelopingdraftlistsameetingwascon-
cessofbeingupdatedforamphibianstoreflectcurrenttaxon- vened by the core planning group to bring together experts
omyandweusedthecorrecteddatainthisdatabasetocreate fromtheregion,particularlyfrommuseumsandotherinsti-
lists of species for DRC and to add records to sites. Laurent tutions to review and augment the draft species lists. This
(1972)increasedtheamphibianlistofdeWitteforVirungaNa- meeting also addressed threats to these sites and refined
tional Park and corrected some mis-identifications. Laurent the listsof endemicspeciesforthe AlbertineRift. Following
(1964)wasusedtocompilealistofamphibiansfortheItombwe thismeetingtherewasanotherperiodofsixmonthsadding
Massif.D.Meirteprovidedcorrectionstothetaxonomyofthe tothedataandinparticularcheckingspeciesnamesandsyn-
olderliteratureandalsoaddedmanyspeciesfromthedatabase onymsbecausetaxonomyofmanyspecieshaschangedover
attheRoyalMuseumforCentralAfricaatTervuren.Somedata the70yearsofpublicationsthatwereused.WCSandMake-
ondistributionandsystematicsoftreefrogsweretakenfrom rereUniversitywereinvolvedinthisdatacleaning.
Schiøtz (1999). Only limited data were obtained for Burundi Numbersofendemicandgloballythreatenedspecieswere
andnoneforTanzania. calculatedforeachsiteandusedtoprioritisesitesintheAlb-
ertineRiftforconservationas follows.Endemicspecieslists
2.1.5. Butterflies were compiled with the help of experts in each taxonomic
InformationwasdrawnfromavarietyofsourcesincludingCar- field.ThemammallistcamefromConservationInternational
casson(1961,1975),d’Abrera(1980,1997),Henning(1988),Kiel- (J.Pilgrim)withadditionsbyJ.KerbisPeterhans.Thelistcom-
land(1990),Larsen(1991),Ackeryetal.(1995),Davenport(1996), piledbyStattersfieldetal.(1998)wasusedforbirds.Thispub-
Howard and Davenport (1996), Congdon and Collins (1999), licationrecognizedtwoareasofendemisminthisregion;the
Congdonetal.(2001),aswellasnumerousworkersfromearlier Albertine Rift and the Eastern Zairean Region of endemism.
partsofthelastcenturyreferencedinthesepublications.Addi- However,somespeciesendemictotheAlbertineRiftoverlap
tional information came from collections held at Makerere substantiallywiththosefromtheEasternZaireanregion(M.
UniversityZoologyMuseum,Kampala,andtheNationalMuse- Herremans–datafromAfricaMuseumatTervuren)andthe
umsofKenya,Nairobi.SteveCollins(ABRI,Nairobi)provided planninggroupmadethedecisionthatitwasbettertocom-
considerable and invaluable information, and we are very binethesetwoareasinthisanalysis.Listsofendemicreptile
grateful to C. Congdon (Tanzania) and A. Gardiner (Zambia) andamphibianspecieswerecompiledbyD.Meirte.T.Daven-
forveryusefulcommentsonanearlierdraft. portcompiledalistofendemicbutterflyspeciesincollabora-
tionwithS.Collins,C.CongdonandA.Gardiner.E.Ndomba,P.
2.1.6. Plants Ssegawa,G.EiluandA.Plumptreworkedwithbotanistsatthe
The main starting point for Uganda was the tree surveys RoyalBotanicGardens,Kew,andMissouriBotanicalGardens
undertaken by the Uganda Forest Department (Howard and todevelopapreliminarylistofendemicplantspeciesbased
Davenport,1996).AdditionaldatawasaddedbyG.Eilu(climb- uponpublishedfamilydescriptionsfrommostexistingAfri-
ers)Poulsen(1997,terrestrialherbs)andD.Hafashimana(epi- canfloras(EastAfrica,Congo,Cameroon,Gabon,andZambe-
phytes) for several forests. WCS has also been surveying siaca).Thislistislikelytomissmanyspeciesbecausemany
many of the Rift forests over the past year and the species familieshavenotbeendescribedinDRCorEastAfrica.Ende-
identified were incorporated in the database by D. Nkuutu. mic species lists are given in Plumptre et al. (2003) and are
Lock(1977)providedalistofspeciesforQueenElizabethNa- also at www.albertinerift.org. Globally threatened species
tional Park. Nabanyumya (1991) listed trees for Kalinzu and were derived from the 2002 IUCN Red List (Hilton-Taylor,
BIOLOGICAL CONSERVATION 134 (2007) 178–194 183
2000andupdatedlistsontheassociatedwebsitewww.iucn- maximumrank(4inthecaseofreptiles).Ameanrankwasthen
redlist.org)andBirdLifeInternational(2000). calculatedforbothendemicandgloballythreatenedspecies
foreachsiteacrossthefivetaxabysummingranksfromeach
2.2. Rankingsitesforconservation taxonanddividingthisbythenumberoftaxaforwhichthere
weresurveydata(i.e.,forwhichaninitialrankwasevenpossi-
While there is a danger that ranking sites in terms of their ble).Thesefinalstandardisedscoreswerethenranked(1–38)to
conservation value can lead to the lower-ranked sites being rankalltheavailablesitesforwhichwecompileddata.Thus,
sidelined, it is still important that priorities are identified thefinalrankingsallowbettercomparisonofsiteswithvarying
given the limited human and financial resources available levelsofknowledge.Inpresentingtheresultswegroupedsites
for conservation. However, even the poorest sites for which intocategoriesofhigh,mediumandlowrankratherthanusing
we have compiled data are rich, in a global context, have actualrankingvaluesforeachsite.Thisavoidsfalseprecision
manyrestricted-rangespecies,andthereforedeserveconser- becausethedataformanysitesareincomplete,somemean
vationattention. rankingscoresarebaseduponjustonetaxon,andtheeffort
Ranking using species data requires subjective decisions, madeinsamplingsitesvarieswidely.Comparingtherankings
particularlywhendataareincomplete.Onlyfivetaxa(mam- forendemicandgloballythreatenedspeciesallowsananalysis
mals,birds,reptiles,amphibiansandplants)canbeusedinthis oftherelativeimportanceofthesetwocriteria.
studyoftheRiftbecausespeciesdataarenotcollatedoravail- The ranking process described above did not attempt to
ableforothertaxa.Intheabsenceofmoreextensivedata,we correctfortheareaofthesites.Weweremoreinterestedin
canonlyhopethatthesetaxaactasgoodsurrogatesforothers. which are the priority sites for species conservation in the
Severalaspectsofsurrogacyweretestedbetweenthesetaxa. AlbertineRiftratherthanwhicharetherichersitesrelatively
Thisindicatedthat,inmanycases,onetaxoncouldactasarea- when area is standardised. From a conservation perspective
sonablesurrogatefortheotherfouracrossthesitessurveyed the larger a site is, the easier it is to manage compared to
(Plumptreetal.,2003).Numbersofendemicspeciesforonetax- manysmallersitesofthesame totalarea; conservingafew
oncorrelatedwell(PearsonCorrelations)withnumbersofen- large sites will in general be the cheaper option. However,
demicspeciesinanothertaxon,forallpossiblecombinations forcomparison with other studieswe did make this correc-
(P<0.001foralltests).Surrogacyforthreatenedspecieswas tion.Wecorrectedforareabycalculating
not so good. Numbers of threatened mammals, amphibians
scoredendemicorthreatenedspecies
andbirdscorrelatedwellbetweensitesbutthreatenedplants
¼lnðnumberof speciesþ1Þ=lnðareaÞ:
andreptilesdidnotshowanysignificantcorrelationwithother
taxa.However,plantsandreptileshavebeenlesscompletely
assessedforthreatenedspeciesthantheotherthreetaxa.Only 3. Results
tworeptileswereclassifiedasthreatenedinthisregioninthe
2002RedList.Iftotalnumbersofspeciesareusedtoranksites
Theresultsshowthatthisregioncontainsmorethanhalfof
thenplantswilldominatetherankingsbecauseofthelarger
continentalAfrica’sbirdspeciesandnearly40%ofitsmammal
numberofspecies.Thegeneralpublicmaywishtoranksites
species.Reptileandamphibianspeciesdonotappearasabun-
onmammalandbirdfaunabecausethesearepopular.Alterna-
dant but this may be a function of the effort that has been
tively,itmightbebettertoprioritisesitesonspeciesthathave
madeincollecting,identifyingandcataloguingtheminthisre-
economicvalueandcanattracttouristsorprovidelivelihoodto
gion.Whileinvertebratetaxahavebeenpoorlysurveyed,this
localcommunities,orbytheirecologicalroleintheecosystem.
regionisknowntohavealargenumberofendemicbutterflies
Weightingscouldbemadeforcertainspeciesorcertaintaxato
(probably the best surveyed invertebrate taxon). The results
incorporatetheseideas.Herewehavedecidedtoweighttaxa
presentedherearethecurrentstateofknowledge,whichwill
equallysothatahighnumberofmammalspeciesatasitere-
beimprovedoninduecourseasmoresurveysareconducted.
ceivesthesamerankasahighnumberofplantsirrespective
ofthe actualnumberofspecies.This effectivelygives equal
weighttoanytaxonandranksbiodiversityperseratherthanso- 3.1. Biodiversityvalues
cial,economicorecologicalfunctionsofbiodiversity.
Siteswererankedintermsofthenumberofendemicand 3.1.1. Mammals
numberofgloballythreatenedspeciesforeachtaxon.These NoendemicfamiliesoccurintheAlbertineRiftbuttwoende-
rankingscoreswerestandardizedforeachsitebydividingby micgeneraoccur,Rwenzorisorex,andDelanymys.Atotalof402
themaximumrankscoretoaccountforthefactthatsomesites mammalspecies (158 generaand 46 families)have been re-
do not havedata forall taxa and to account for thevarying cordedintheAlbertineRift,ofwhich35areendemic(Table1).
numberofendemicorthreatenedspeciesbetweentaxa.For Most of the endemic mammals are shrews and rodents. Of
example,onlytworeptilespeciesarecurrentlylistedasthrea- thelargerendemicmammals,theeasterngorillaisthebest
tenedofthe175speciesfoundintheAlbertineRiftsites(pri- knownandhastwosubspecies(mountain,Gorillaberingeiberin-
marily because reptiles have not been well assessed). Three gei,andGrauer’s,Gorillaberingeigraueri,gorillas).TheRwenzori
siteshavethreatenedreptiles,whichmeansthatallsiteswith duiker,Cephalophusrubidus,andthegoldenmonkey,Cercopithe-
no threatened reptiles scored a value of ‘4’ in the rankings. cus kandti, are two other medium sized endemic mammals.
Howeverarankvalueof‘4’forbirdsisahighvaluewithmany Smallmammalshavebeenpoorlysurveyedthroughoutmuch
threatened species and therefore ranks cannot be summed oftheRift,particularlytowardsthesouthernend,anditisvery
across taxa without standardizing them by dividing by the likelymorespecieswouldbeaddedwithfurthereffort.
184 BIOLOGICAL CONSERVATION 134 (2007) 178–194
Table1–RichnessofmammalsacrosssitesoftheAlbertineRiftMountains,includingnumberofspecies,
numberofAlbertineRift(AR)endemicspecies,andnumberofgloballythreatenedspecies(CR=CriticallyEndangered,
EN=Endangered,VU=Vulnerable)
Site Speciesno. ARendemicspecies ThreatenedCR,EN,VU
BudongoFRa 95 0 5
BugomaFR 38 0 4
BugunguWR 9 0 1
BururiFR 9 1 1
BwindiImpenetrableNPa 135 20 7
EchuyaFRa 24 7 1
ForestWestofLakeEdward 8 0 1
GombeNP 19 1 4
IbambaroFR 2 0 0
ItombweMassif 72 4 10
ItwaraFR 18 0 0
KagombeFR 14 0 3
KahuziBiegaNPa 136 15 14
Kalinzu–MaramagamboFRa 58 1 3
KarumaWR 57 0 4
Kasyoha–KitomiFRa 47 2 3
KibaleNPa 115 5 7
KibiraNPa 71 8 7
KitechuraFR 17 0 1
KyamburaWR 37 0 3
MafugaFR 20 3 1
MahaleMountainsNPa 52 1 6
MatiriFR 12 1 0
MbiziFR 23 1 2
MurchisonFallsNPa 109 0 5
Mweru-WantipaNPa 50 0 7
NyungweNPa 86 14 3
QueenElizabethNPa 97 0 6
RwenzoriMountainsNPa 102 18 10
SemlikiNPa 86 1 5
SemlikiWR 69 0 4
SumbuNPa 61 0 6
VirungaNPa 196 21 13
Total 402 35 36
a Reasonablysurveyedforallmammals.
Virunga National Park in eastern DRC has the highest Althoughthisisthemostthoroughlysurveyedgroupofani-
numberofendemicmammalspecies(21).BwindiImpenetra- mals,newspeciesfortheRiftcontinuetobeaddedasmigrant
bleNationalPark(20)andRwenzoriMountains(18)ranknext species and new range extensions are recorded. Within our
highest. definitionoftheAlbertineRifttherearetwocontiguousEnde-
Thirty-fourmammalspeciesaregloballythreatened(Crit- micBirdAreas(EBAs)definedbyBirdLifeInternational:Alber-
ically Endangered, Endangered or Vulnerable) according to tineRiftandEasternZaireanLowlands(Table2)(Stattersfield
the 2002 IUCN Red List (Hilton-Taylor, 2000; www.iucnred- etal.,1998).Wehavecombinedtheseareasbecauseoldmu-
list.org), of which 12 are Albertine Rift endemics. These in- seumcollectionsofAlbertineRiftendemicspeciesshowthey
clude eastern gorilla (Gorilla beringei), golden monkey and occuratloweraltitudesineasternDRCandthattheyoverlap
Rwenzori otter shrew Micropotamogale ruwenzorii. Kahuzi inaltitudinalrangewiththeEasternZaireanlowlandspecies
Biega National Park had the highest number of globally (Boberetal.,2001;Herremansetal.,2002).Thetotalnumber
threatenedmammals(14)followedbyVirungaNationalPark of endemic birds in the Albertine Rift as defined here is 41
(13). species,whichincludestheendemicsofthesetwoEBAs.
The Itombwe Massif, an unprotected area west of the
3.1.2. Birds northern end of Lake Tanganyika, contains more endemic
Three genera are endemic to this region, Pseudocalyptomena, speciesthananyothersiteintheAlbertineRift(34).Itisclo-
Graueria,andHemitesiabutnofamiliesareendemic.Atleast selyfollowedbyKahuziBiegaNationalPark(30)andVirunga
1061 bird species (in 368 genera and 80 families) occur in NationalPark(27).
theAlbertineRift(Table 2) ofwhich 4.5%are migratoryspe- Twenty-fiveAlbertineRiftspeciesaregloballythreatened,
ciesthatoverwinterintheregionbutdonotbreed,orwhich 13 of which are endemics. These include congo bay owl
pass through on migrations within the African continent. (Phodilusprigoginei),itombwenightjar(Caprimulgusprigoginei),
BIOLOGICAL CONSERVATION 134 (2007) 178–194 185
Table2–RichnessofbirdsacrosssitesoftheAlbertineRiftMountains,includingnumberofspecies,numberofAlbertine
Rift(AR)endemicspeciesasdefinedbyBirdLifeInternational(withnumberofeasternZaireanlowlandendemicspeciesin
parenthesesthatwereincludedinthedefinitionofAlbertineRiftEndemicspecieshere–seetext)andnumberofglobally
threatenedspecies(CR=CriticallyEndangered,EN=Endangered,VU=Vulnerable)
Site Speciesno. ARendemicspecies ThreatenedCR,EN,VU
BudongoFR 362 0 1
BugomaFR 221 0 1
BururiFR 155 13 3
BwindiImpenetrableNP 381 24(1) 6
EchuyaFR 136 14 2
ForestsWestofLakeEdward 420 25 11
GombeNP 267 0 2
Idjwi 150 2 1
ItombweMassif 583 34(4) 15
ItwaraFR 183 0 0
KagombeFR 121 0 0
KahuziBiegaNP 335 32(3) 11
Kalinzu–MaramagamboFR 393 4 1
Kasyoha–KitomiFR 308 2 1
KibaleNP 327 3 3
KibiraNP 211 21 7
KitechuraFR 90 0 0
KyamburaWR 450 0 6
LenduPlateau 317 6 4
MafugaFR 130 10 0
MahaleMountainsNP 250 2 1
Marungu 282 1 0
MatiriFR 119 0 0
MbiziFR 116 0 0
MtKabobo 231 18 3
MurchisonFallsNP 476 0 7
NyungweNP 280 26 7
QueenElizabeth 594 0 7
RusiziNR 182 1 3
RwenzoriMountainsNP 241 21 4
SemlikiNP 441 7(5) 9
SemlikiWR 435 0 3
VirungaNP 706 27(2) 11
Total 1061 41(6) 25
IntheanalysespresentedinthispaperAlbertineRiftandEasternZaireanLowlandendemicspecieswerecombinedbecauseoftheextensive
overlapindistributionsofthetwogroupsascanbeseenhere.
kungwe apalis (Apalis argentea), grauer’s rush warbler (Brad- SixteenendemicreptilespeciesoccurintheRift,ofwhich
ypterusgraueri)andgolden-napedweaver(Ploceusaureonucha). VirungaNationalParkcontainsthehighestnumber(11),fol-
Itombwehadthehighestnumberofgloballythreatenedspe- lowedbyRwenzoriMountainsNationalPark(9)andNyungwe
cies(15)followedbyVirungaNationalPark(11),KahuziBiega National Park (8). Endemic species include five chameleons
National Park (11) and the mountains west of Lake Edward such as the strange-horned chameleon (Bradypodion xenorhi-
(11). num), and Johnston’s chameleon (Chamaeleo johnstoni), two
colubridsnakes,oneviper,sixskinks,onewormsnake(Lepto-
3.1.3. Reptiles typhlops)andonelacertidlizard.
Noendemicgeneraorfamiliesofreptilesareknownfromthe Only two globally threatened reptiles are currently listed
AlbertineRift. A total of 175 reptiles, from 69 genera and 20 fortheAlbertineRift(TrionyxtriunguisandOsteolaemustetra-
families (about 14% of Africa’s reptiles) have been recorded spis). However, this is because the region has few data and
fortheAlbertineRift(Table3).Farfewersiteshavebeensur- reptiles as a whole have not been assessed completely for
veyed for reptiles to the same extent as for mammals and theirthreatenedstatus.TheIUCNGlobalReptileAssessment
birds, although some records existed for at least 33 sites. isunderwayanditislikelymanymorespecieswillbeadded
Itombwe Massif and Kahuzi Biega National Park in eastern totheRedList.Asaresultnositehasmorethanoneglobally
DRCmaycontainmanyspeciesbuttodatehavebeenpoorly threatenedreptile(Table3).
surveyed. Other areas that need work include the Marungu
MassifineasternDRCatthesouthernendofLakeTanganyika 3.1.4. Amphibians
andtheMahaleMountainsNationalParkanditssurrounding Three amphibian genera are endemic to the Albertine Rift;
naturalvegetation. Laurentophryne, Chrysobatrachus and Callixalus. There are 119
186 BIOLOGICAL CONSERVATION 134 (2007) 178–194
Table3–RichnessofreptilesacrosssitesoftheAlbertineRiftMountains,includingnumberofspecies,number
ofAlbertineRift(AR)endemicspecies,andnumberofgloballythreatenedspecies(CR=CriticallyEndangered,
EN=Endangered,VU=Vulnerable)
Site Speciesno. ARendemicspecies ThreatenedCR,EN,VU
BudongoFR 48 1 0
BugomaFR 9 0 0
BugunguWR 9 0 0
BururiFR 1 1 0
BwindiImpenetrableNP 34 6 0
EchuyaFR 4 0 0
ForestsWestofLakeEdward 6 3 0
GombeNP 1 0 0
ItombweMassif 35 5 0
ItwaraFR 10 0 0
KahuziBiegaNP 69 7 0
Kalinzu–MaramagamboFR 9 0 0
KarumaWR 15 0 0
Kasyoha–KitomiFR 9 0 1
KibaleNP 56 3 0
KibiraNP 3 2 0
KyamburaWR 12 0 0
L.Rukwa 7 0 0
L.Tanganyika 13 0 0
LenduPlateau 6 0 0
MafugaFR 17 2 0
MahaleMountainsNP 4 0 0
MarunguMassif 6 0 0
MbiziFR 3 0 0
MtKabobo 6 2 0
MurchisonFallsNP 32 0 1
NyungweNP 43 8 0
QueenElizabeth 34 0 0
RusiziNR 3 0 0
RwenzoriMountainsNP 34 9 0
SemlikiNP 49 0 0
SemlikiWR 33 0 1
VirungaNP 109 11 0
Total 175 16 2
speciesofamphibiansintheAlbertineRift,including29gen- (Snoeks, 2000). Only Lake Malawi has more endemic fish in
eraand11families,(about19%ofAfrica’samphibians). Africa. Fifty-six fish species are endemic to lakes George
Thirty-sixendemicspecieshavebeenidentified.Itislikely andEdward,whileKivuandAlberthave15andsixendemic
thatmoresurveyeffortwoulduncoverfurtherendemicspe- fish respectively. Only 10% of Lake Tanganyika’s shore has
cies.VirungaNationalParkhadthehighestnumberofende- beenexploredandatotalofover1200faunalspecies(verte-
micspecies(16)withItombweMassif(16)andNyungwePark brates and invertebrates) have been recorded, making it the
(14).Fourendemicspecies(Hyperoliuspustulifer,Schoutedenella secondhighestrecordeddiversityforanylakeonearth(Patt-
loveridge,Schoutedenellamossoensis,Schoutedenellavercammeni), ersonandMakin,1998).
have only been recorded outside the 40 sites described here
and are thus not found in any of the protected areas in the 3.1.6. Butterflies
AlbertineRift. ThetotalnumberofbutterflyspeciesfoundintheAlbertine
SixteenAlbertineRiftamphibiansaregloballythreatened, Riftisunknown,asthisinformationcannotbecompiledun-
of which 14 are endemic. Itombwe Massif has more threa- til many more areas have been surveyed, particularly in
tened species (CR, EN or VU) than other sites (11) followed eastern DRC. In Uganda, inventories of the forests in the
by Virunga National Park with 10 and Bwindi Impenetrable AlbertineRifthaveshownthatatleast581speciesofbutter-
NationalParkwithsix(Table4). fly,16%oftheestimated3630speciesinAfrica,occurinthis
part of the Albertine Rift alone (Howard and Davenport,
3.1.5. Fish 1996). It is possible that, given the numbers from Uganda
While no attempt was made to put together species lists of and Tanzania, up to 1300 butterfly species might occur in
fishfortheriversandlakesintheAlbertineRift,theliterature theRift,about35%ofAfrica’stotal.Therearenoknownen-
wassearchedfordataonthemajorlakes(Albert,George,Ed- demicfamilies,butthegenusKumothalesisrestrictedtothe
ward,KivuandTanganyika).LakeTanganyikaalonehas289 AlbertineRift.Itisknownthat117endemicspeciesfrom49
endemicspeciesthatmakeup89%offishdiversityofthelake generaexistintheAlbertineRift(Plumptreetal.,2003).The
BIOLOGICAL CONSERVATION 134 (2007) 178–194 187
Table4–RichnessofamphibiansacrosssitesoftheAlbertineRiftMountains,includingnumberofspecies,number
ofAlbertineRift(AR)endemicspecies,andnumberofgloballythreatenedspecies(CR=CriticallyEndangered,
EN=Endangered,VU=Vulnerable)
Site Speciesno. ARendemicspecies ThreatenedCR,EN,VU
BudongoFR 32 1 1
BugomaFR 20 1 0
BururiFR 4 4 1
BwindiImpenetrableNP 29 6 6
EchuyaFR 19 5 1
ForestsWestofLakeEdward 6 6 3
ItombweMassif 23 16 11
ItwaraFR 19 0 0
KahuziBiegaNP 25 7 4
Kalinzu–MaramagamboFR 25 2 2
KarumaWR 16 0 0
Kasyoha–KitomiFR 16 3 2
KibaleNP 33 5 3
KibiraNP 1 0 0
KitechuraFR 15 0 0
KyamburaWR 14 0 0
MafugaFR 1 1 0
Marungu 19 1 0
MatiriFR 15 0 0
MtKabobo 8 7 5
MurchisonFallsNP 14 0 0
NyungweNP 33 14 5
QueenElizabethNP 10 1 1
RwenzoriMountainsNP 25 7 1
SemlikiNP 24 1 0
SemlikiWR 13 0 0
VirungaNP 65 16 10
Total 119 36 16
total number of endemics (of which 85% are forest depen- crease greatly when lower plants and little studied growth
dent) is considerably larger than the 78 endemic species forms such as climbers, epiphytes, lichens and bryophytes
found in the Eastern Arc Mountains and coastal forests of are included. Western Tanzania, especially around Mahale
TanzaniaandKenya,andcouldincreasewithfurthersurvey Mountains National Park, appears to be particularly rich in
effort. Whether or not butterflies are indicative of other plantspeciesandyethasstillnotbeensurveyedintensively.
invertebrate species is unclear but these numbers do dem- As such it deserves more attention. Virunga National Park
onstrateunequivocallythatthisregionisnotonlyimportant in eastern DRC and Bwindi Impenetrable National Park in
for vertebrate conservation. Uganda had the highest numbers of plant species recorded
butbothsiteshavebeenrelativelyintensivelysurveyed.The
3.1.7. Plants Marungu Massif and Itombwe Massif in eastern DRC have
Higherplantshavebeenrelativelywellsurveyedintheforests few records but also could be relatively rich and require
of Uganda and Rwanda but elsewhere in the Albertine Rift surveys.
surveyshavebeenpatchy.Currently5793plantspecies(from
1537generaand233families)havebeenrecordedwithinthe 3.2. Sitepriorityrankings
Riftbutthiswillchangeassurveysarediscoveringnewspe-
cies regularly even within Uganda (Table 5). These data in- Rankingsweremadefornumbersofbothendemicandglob-
clude ferns and higher taxa but do not include the allythreatenedspeciesforalltaxa(mammals,birds,reptiles
bryophytes and lichens, which are very poorly surveyed. amphibiansandplants),foreachsiteasexplainedinSection
Thenumberofplantspeciesishighcomparedwithmanyre- 2.2(Table6).Wethengroupedthesitesintohigh(rankscores
gions of similar size and forms 14% of all mainland Africa’s 1–12),medium(rankscores13–24)andlow(rankscores25–38)
estimatedplantspecies.Apreliminaryestimateofthenum- scoringsitesforbothcriteriaandplottedtheresultsinatwo-
bers of endemic plant species has been compiled by the waytableforendemicandgloballythreatenedspecies(Table
WCS’s Albertine Rift Programme and this now numbers 551 7).Giventhegapsinthedataanddifferencesinsamplingef-
species.Theselistsarebasedonpublishedfloradescriptions fortbetweensiteswebelievethatgroupingthesitesintothe
ofplantfamilies,butmanyfamilieshavenotbeendescribed threebroadrankingcategoriesprovidesamoreconservative
forDRCorEastAfrica.Someinputwasmadebyherbariaex- approachbyalleviatingthesebiases.
perts, but the list is still incomplete. As a result this list Thosesixsitesthatscoredhighestareconsideredtobethe
should be considered to be very preliminary and could in- mostimportantbecausetheyrankhighlyfornumberofboth