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ANDEANBEAR-CATTLE INTERACTIONS ANDTREE NEST USE IN BOLIVIA AND VENEZUELA

R. Wildlife Conservation ISAAC GOLDSTEIN, 2300 Society, NY Southern Bronx, 10460,USA, email: Boulevard, @wcs.org igoldstein

Ursus 13:369-372(2002) Key words: Andean bear, Apolobamba,bear-cattle interactions,Bolivia, corn field raiding, feeding behavior, national parks, spectacled oratus, Venezuela bear,tree nests, Tremarctos

METHODS

FromAugust 1996 to December2000, I surveyedsettlementssurrounding wildernessareaspresentin the Venthe ezuelan Andes, with the exception of the Perijaregion. I defined wilderness area as any tractof forest or pairamo (high altitude treeless ecosystems, characteristicof the tropicalareasof the Andes) bigger than5,000 ha with no humandisturbance. Reports on bear-cattle interactions occurringwithin 2 monthsof my visit were investigated. I documentedthe historyof priorAndeanbear-cattleinnumber cattlelost, andlocationof eachevent. of teractions, At each reportedbear-cattle interactionsite, the carcass remainsandsigns of predator scavengeractivity(beds, or tree nests, scats, trails) were describedand mapped. The state of the carcass was categorizedas fresh (little or no feeding, no decomposition) or decomposing (from partially eatenkill to bones and hide). The above methodology was also used in Bolivia at the ApolobambaNational Parkand surrounding areasduringa Andeanbearsurvey, 2000. August

Andean (spectacled)bears (Tremarctos ornatus)have been reported livestockpredators as theirrange throughout Suarez 1988, Mondolfi 1989, Goldstein (Peyton 1980, 1991a). In Peru,Peyton (1980) reportedthatin orderto kill cattle, bears pursue the animals on steep slopes or nearcliffs to makethemfall. Peyton(1980) also acknowledged reportsthat a bear may carry livestock kills up a tree to consume it in seclusion and protectthe kill from otheranimals. Even thoughcattle remainswere found in Andean bear scats in Peru (Peyton 1980) and Ecuador to (Suarez1988), no field evidencewas gathered discriminate between predationand consumptionof carrionby Andeanbears. The use of tree nests (nest-like platforms)by Andean bearshas been reported severalauthors(Osgood 1914, by Tate 1931, Bridges 1948, Mondolfi 1989, Goldstein 1991b). They describedtreenests as orderedassemblages of bentor brokenbranchespositionedin forkedbranches, resemblinglargenests andused as restingplaces. Peyton (1980) found 5 tree nests in Peru associated with fruit in feeding. Based on his observations Peru,Peyton(1980) suggested that the platformswere used for feeding purposes ratherthan for resting, as had been reported. Althoughthe use of tree nests in relationto fruitfeeding is widely reportedanecdotallyby locals in Venezuela,field investigations have found that tree nests were strongly associated with cattle carcass feeding sites (Goldstein 1991b). No direct evidence of predationon cattle by Andean bearswas gatheredduringthe Andeanbearsurveysdone between 1985 and 1987 in Venezuela. However, some evidence supports cattle predation by Andean bears (Goldstein 199la), including signs of struggle(deep and long hoof markson the ground,uprooted vegetation,cattle with claw marks),the numberof cattle lost at each site, the absenceof sign fromotherpossible predators, the and cessation of cattle losses after the killing of bears. This work reportsnew informationon Andeanbear-livestock predationclaims, carcassfeeding behavior,and tree nest use by Andean bear gatheredfrom 1996 to 2000 in the Venezuelan Andes andin August2000 at the Apolobamba National Parkand surrounding areasin Bolivia.

RESULTS Venezuela

Andeanbear-cattleconflictsin Venezuela werereported at 7 locationswithinthe statesof Merida,Tachira, Trujillo, Barinas, and Lara. All but 1 location (Quebrada El Molino) were inside nationalparks. Five of the 7 locations (Paramo Fiera,Quebrada Molino, ParamoLos La El Angelitos, La Cienaga, and Santa Ana) reportedpredation events within the last year. Cattlepredationwas reported within the 2 months prior to my arrivalat 4 of these 5 locations (excepting La Cienaga). A total of 47 cattle from all locations were reportedlylost to bearpredationduringthe previous 2 years (1999-2000). QuebradaEl Molino.--Of the 9 cattlereporteddead or missing, the remains of 5 decomposing carcasses were located. No fresh kills were found. Seven tree nests and 3 groundbeds were associated with 4 of the carcass remains found. All the tree nests were found in very steep terrain (>70%slope) with extremelydifficultaccess. Skin remains,bone fragments, bones, vertebrae, a skull and leg were found inside 5 of the treenests. On a latervisit, 1 of the tree nests showed signs of recent use. A cattle skull and a partiallyeaten leg were found inside the nest, anda trailleadingfroma paramo areato the treenestwas clearly visible. At 1 site, the bone remainsof cattle were found below a rockycliff in an open paramoarea. At 3 spots on ledges at the cliff I found bone and skin remainsas well as severalbearscats. One site containeda groundbed supported

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Ursus 13:2002 trees 12 to 15 m above ground.

on one side by a small shrub. At this site, the bear had evidently broughtbranchesto build the nest (therewere no other shrubsor trees within 50 m of the site). Paramo Los Angelitos.-A decomposing carsass had been draggeddownhill, leaving a clear trail throughthe paramovegetationleadingto 3 feeding sites and3 ground beds. The groundbeds were within 2 m of each other, and I found cattle bones and cattle and bear hair around the beds. Two old scats containingcattle bone fragments were found just outside 1 of the beds. The beds were built on the highest portion of a very steep slope overlooking the creek bed. Pdramo La Fiera.-Sixteen cattle were reportedlost during the 6 months prior to my visit at this location. AlthoughI foundmuchsign of Andeanbearactivity(e.g., trails, scats, and claw marks on trees), I found no carcasses in the forest below the paramo. The only signs I that encountered suggestedbearfeedingon cattlecarcasses were 4 bearscats containingcattleremainsfoundbelow a and recentlymadetreenest (thebranches leaves thatmade up the nest interiorwere still green). SantaAna and La Cienaga.-I visited these locations after a landownerreportedrepeatedattackson his cattle recalledyearly by bears. At bothlocations,the landowner losses of cattle to bear predationfor the past 30 years. Cattle losses occurred during September and October. Losses variedbetween years with up to 14 cattle lost annually. However,during2000, cattle losses startedat the end of June and continue throughAugust. The owner reporteda total of 21 animals lost during2000. During my visit, we located 18 groundnests and 4 tree nests associatedwith 4 decomposingcarcasses. All groundnests were found in steep terrain(70% slope) at the edge of a ravine. The tree and groundnests had easy access from the paramoabove andfromthe creekbelow. All the nests were connected by trails that in most cases ran perpendicularto the slope. The entire area, including 22 tree bromeliadfeeding andgroundnests, trails,andterrestrial 200 coveredapproximately m2. Most of the ground sites, to nestswere adjacent a shrubandwereneatlyconstructed with branches,fern leaves, and otherplantdebris. Althoughmountainlion (Felis concolor) scats were a common sign in all the wildernessareasvisited, particularly at rocky outcropsand along humantrails,Quebrada El Molino was the only site wheremountainlion scat was found near a cattle carcass visited by bears. Only bear sign was found associatedwith cattle carcassesat all the otherlocations. Treenests associatedwith fruitfeeding were observed trees Merida. Althoughmanyfruit-bearing at El Carrizal, bearclimbingsigns, I distinguished showed at El Carrizal tree nest type platformson only 2 occasions. Both were built on forked brancheshigh in the canopy of fruiting

Bolivia

Cattlepredationby Andeanbearswas widely reported in ranching areas aroundthe town of Pelechuco in the ApolobambaNational Park. On my visit I attended a meeting wherethe cattle ownersaskednationalparkrepresentativesfor compensationfor >70 cattlereported lost to bearpredationin the last 3 years. Cattlelosses within the last 2 months were reportedat Uyuni, Pasto Grande, and Tojoloque. Althoughrecentbear sign was found at all these sites, inspectionsfailed to documentevidence of carcassfeeding or predationby bears within the last year. Only one scat veryold anddeteriorated withboneremainswas found beside a very old groundnest at PastoGrande,indicating a cattle carcassfeeding event by bears. Bear-cattleconflicts in CerroToanaoccurred2 months priorto my visit. Several cattle were reportedmissing. Cattleownersfoundthe remainsof 1 cow associatedwith bear sign, and a bear was shot a week before my visit. I found some signs of recent bear-cattle interactions. An area on the groundwith cattle hide remainswas visible in an open paramo15 m above the forest edge, and a trailon the pairamo vegetationled downslope towardthe forest edge into a ravine. The trail continuedalong the ravine floor, occasionally dipping into a stream. Along cattleribs,3 sites with bone the beartrailI foundscattered bromeliad(Greigia 5 tree nests, 8 terrestrial fragments, 2 epiphytic bromeliad (Tillandsia sp.) feeding sites, superba)feeding sites, and3 bearscats (1 with bone fragments inside a tree nest and the other 2 with bromeliad remains). Although cattle owners reportedpermanent presence of Andean bears in the area, predationevents were reportedas uncommon. I found tree nests in Bolivia at Pasto Grande,Pajan, and Cerro Toana. The Cerro Toana nests were clearly associatedwith cattle carcassfeeding. Six tree nests and 1 groundbed were found at Pajanin a small forest patch (about4 ha), 200 m from the Pajancornfieldson the opposite bank of the Disiyakha river. Two nests were observed at Pasto Grandeon a Prunussp. tree at 5 and 7 m above the ground.

DISCUSSION

Bear-cattleconflicts in Bolivia andVenezuelaoccur at remote cattle herding grounds in open grasslandareas, near large tracksof cloud forest. In Venezuela,all but 1 location with bear-cattle conflicts were inside national parks. The paucity of informationon bear-cattle conflicts is due to the lack of monitoringby national park authorities.Livestock owners take it upon themselves to

SHORTCOMMUNICATIONS 371

deal with bear predationwithout notifying the authoribearsand all other ties, usually by huntingthe "problem" bearsthat happento be in the area. Conflicts in Venezuela were localized at sites with a long history of bear-cattle interactionswhere they seem to happen at intervalsof up to 10 years. Five of the 12 Venezuelan locations reportedby Goldstein (1991a) as having bear-cattleconflicts had conflicts duringour survey. At the 2 newly reportedlocations, investigationrevealed thatboth had a long historyof cattle predationby bears. SantaAna was the only locationwherebear-cattle conflicts were reportedannually. The concentrationof conflicts in relativelyfew locationswill allow close monitoringand aid in developing a programaimedat preventing cattle loss and conservingbears. As reportedfor brown bears (Ursus arctos) in Spain (Clevenger et al. 1994) and Norway (Mysterud 1973), Andeanbears leave many signs aroundcarcass sites. At carcass sites in Venezuela, the bears often used ground restingsites as well as groundand treenests while spending several days feeding on a single carcass. In Bolivia andVenezuela,cattlecarcassesweredragged downslopefromopen paramoareastowardforestedcreek beds. Once at the creek, the carcass was draggedto differentfeeding sites severaltimes, confirmingthe reported general feeding behavior on cattle carcasses (Goldstein 1991a). The only differenceI encountered duringthe latest cattle carcass feeding episodes was that a proportion of treeandgroundnests were clearlyused as feeding sites. All ground and tree nests found in and aroundcarcass areaswere foundon strategic ledges orhillsideswith steep difficultaccess, anda panoramic view of the whole slopes, area-a perfectsite for observationanddefensepurposes. Tree nests found associated with fruit feeding at El Carrizal to correspond Peyton's(1980) descriptionof tree nestsassociatedwithfruitfeeding. However,I foundsome differenceswith tree nests describedby Peyton (1980) as feeding sites. First, platformsencounteredin Venezuela were located at the highest part of the canopy with no other branchesabove, indicatingthat the purposeof the platforms was not to reach other branches furtherup. Second, many trees exhibited fruit feeding sign, such as pruningof branches,near tree nests but had no signs of tree nests in theircanopies. This suggests thatplatforms are neithernecessary nor habituallyused in fruitfeeding in Venezuela. The pruningof branchesand the buildingof tree nests appearto be a commonAndeanbearbehavior,not necessarily associated with feeding higher up in the trees. A bear cub (approximately7 kg) capturedin the wild and broughtto the Badarida Zoological Parkin Barquisimeto, was released in a new open enclosure with Venezuela,

naturaltrees. The cub immediatelyclimbed up the highest branch,prunedseveral branches,and made a rustic nest in which he spent 1 week, only climbing down at night to feed. Otherzoo bears were laterreleasedin the same enclosure,where they also climbed the highest and thinnestbranchesand prunedall the trees in the exhibit (Jose Pemalete,Badarida Zoological Park,Barquisimeto, Venezuela, 2000). This supports personalcommunication, the concept thatplatformsserve multiplebehavioralpurposes for Andeanbears,suchas feeding,resting,or guarding posts at feeding sites (Goldstein 1991b). We noted that Andeanbears hauled partsof carcasses up trees,andnot the whole carcassas commonlyreported El (Peyton 1980). At Quebrada Molino, the bearor bears that fed on cattle carcasses used the same general area while feeding on the carcasses, and even used the same tree nest to cache remainsfrom differentcattle carcass. Because cattle predationended after 1 bearwas killed, I assumedonly 1 bearwas predatingon cattle at each location (Goldstein 1991a). This was supportedby anecdotalinformation fromcattleowners. However,evidence from Santa Ana suggests that more than 1 bear fed on carcasses. There, 2 carcasses were consumed simultaneously and a numberof beds or nests were found at the feeding site. The informationgatheredat bear-cattle conflict areas in Bolivia andVenezuelademonstrate most cattledisthat is blamed on bear predation,an assumption appearance that is not always true as the experiences at ParamoLa Fiera,Venezuela,andPastoGrande, Bolivia, have shown. At all sites where Andeanbear fed on cattle that we visited in Bolivia and Venezueladuringthis study,we found cattlecarcassesassociatedwith only veryold decomposing bear activity signs. We also found no field evidence to discriminatebetween predationand consumptionof carrion. For thatreason, I have used the term cattle carcass feeding insteadof cattle predation. Knowledgeof how manyindividualbearsareinvolved in a carcassfeeding event and the predatory capacityand is of key importanceto future managementof intensity bears in conflict areas. Bear-cattle conflicts continueto be a problemthroughoutthe distributionof the Andean bear in Venezuelaand are importantissues where extensive highlandherdingpracticestake place in Bolivia.

ACKNOWLEDGMENTS

The Bolivian portionof this researchwas partiallyfinanced by the Center for EnvironmentalResearch and Conservation the and (CERC),through grant"Biodiversity Land Use Zoning of the Newly ExpandedApolobamba Integrated ManagementArea".

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Ursus 13:2002 W.H. of across northern OSGOOD, 1914.Mammals anexpedition Peru. Zoology Series Field MuseumNaturalHistory 10:143-185. Publication B. 1980. Ecology,distribution food habitsof and PEYTON, of bears,Tremarctos oratus, in Peru. Journal spectacled 61:639-652. Mammalogy E. and SUAREZ, 1988. Seasonaldistribution food habitsof of oratus, in the highlands bears,Tremarctos spectacled and Ecuador.Studieson Neotropical Fauna Environment 23:133-136. of G.H. 1931. Random observations habitats South on TATE, American Journal Mammalogy of mammals. 12:248-256. Received: 28 May 2001. Accepted: 29 March2002. Associate Editor: Immell.

LITERATURE CITED

of W.L. 1948. Wildanimals theworld.Garden BRIDGES, City Publishers Garden New York, USA. City, Company, AND M.A.CAMPOS, A. HARTASAMCHEZ. 1994. CLEVENGER, A.P., on Brownbear,Ursusarctos,predation livestockin the Cantabrian 39:267mountains, Spain. ActaTheriologica 278. I. 1991b. Arespectacled bear'streenestsfeeding GOLDSTEIN, orresting Mammalia 55:433-434. platforms places? bear and behavior 1991a.Spectacled predation feeding Fauna on livestockin Venezuela.Studieson Neotropical andEnvironment 26:231-235 food E. 1989. Noteson the distribution, habitat, MONDOLFI, habits, status and conservationof the spectacledbear Mammalia 53:525-544. (Tremarctos oratus) in Venezuela. of bears at I. (Ursus MYSTERUD, 1973. Behavior brown arctos) of Journal Zoology21:267-272. moosekills. Norwegian

PROBABLE GRIZZLYBEAR PREDATIONON AN AMERICAN BLACK BEAR IN

YELLOWSTONE NATIONAL PARK a a a

i l II ~' I Ia IaII ! I I a % I _Ii i I i, _ a II_ ,.

A. KERRY GUNTHER, Bear Management Office,P.O.Box 168, NationalPark,WY82190, USA, email: Yellowstone nps.gov [email protected] MARK BIEL, J. Bear Management Office,P.O.Box 168, NationalPark,WY82190, USA,email: Yellowstone mark_biel nps.gov FishWildlife Parks,1400 South and Montana NEIL ANDERSON, Bozeman,MT59715, USA, email: [email protected] 19th, of LISETTE Resources, WAITS, Department Fish and Wildlife of University Idaho,Moscow,ID83844-1136, USA, email: [email protected] Ursus 13:372-374(2002)

Key words:Americanblackbear,grizzlybear,interspecifickilling, predation, Ursus americanus,Ursus arctos, YellowstoneNationalPark

Both grizzly bears (Ursus arctos) and Americanblack bears (U. americanus)live in YellowstoneNationalPark (YNP), which is locatedprimarilyin Wyoming,USA. In areaswhere grizzly bears and black bearsare sympatric, temporalisolation and behavioraldifferences likely reducedirectcompetitionbetweenthe species (Aune 1994). In the GreaterYellowstone Ecosystem (GYE), grizzly bearsaregenerallymost active duringnocturnalandcretimes (Schleyer1983, Holmet al. 1999), whereas puscular black bears are mostly diurnal(Barnes and Bray 1967, Holm et al. 1999). Grizzly bearsevolved to exploit nonforestedhabitats,whereasblack bears are primarilyforest adapted(Herrero1978). Grizzlies are also generally largerthanblack bears and much more aggressive in defendingthemselvesandtheiroffspringfromconspecifics and otherpredators(Herrero1978), whereasblack bears by typicallyescape predators runninginto forestcover or

climbing trees (Herrero1985). Due to theirlargerbody size, grizzly bearshave a competitive advantageover black bearsin largenon-forested areas (Herrero1977). Although displacementof black bearsby grizzly bearsfrom high qualityhabitathas been documented(Shaffer 1971, Kendall 1984, Aune 1994), interspecifickilling of black bears by grizzly bears has (Arnold1930, Jonkeland only occasionallybeen reported Cowan 1971, Murie 1981, Ross et al. 1988, Mattsonet al. 1992). We documentedprobablegrizzly bearpredationon an adultmale black bear in HaydenValley, in centralYNP. HaydenValley is a large (>8,500 ha) non-forestedvalley surrounded the forestedCentralPlateau. Florain the by valley is dominatedby sagebrush(Artemesiaspp.) and a variety of forbs, grasses, and sedges (Meagher 1973). wetlandsare presentin Numerousgraminoid-dominated the valley. Lodgepole pine (Pinus contorta)forest types thatoccuron infertilerhyolitesoils dominatethe forested plateau surrounding Hayden Valley (Despain 1990). Spruce(Picea engelmannii)-fir(Abieslasiocarpa)stands are interspersedthroughoutthe lodgepole pine zone in areas of more favorablemoistureregimes such as pond margins, north slopes, and drainages (Graham 1978). Grizzly bearsare active in both the forestedandnon-forthe ested areasof HaydenValleythroughout non-denning season (Guntheret al. 1995). Black bearsaremostly observed within and nearthe edges of the forestedportions of the valley and rarelyfar from forest cover in the nonforestedareas(Guntheret al. 1995). On 2 August 1998 we received a reportof a deadblack bear on the northeastside of the Yellowstone River in Hayden Valley, across from the Grizzly Overlook interpretivesign along the GrandLoop road. We investigated

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