Observations on Food Habits of Asiatic Black Bear in Kedarnath Wildlifesanctuary, India: Preliminaryevidence on Their Role in Seed Germination and Dispersal
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SHORT COMMUNICATIONS Observations on food habits of Asiatic black bear in Kedarnath WildlifeSanctuary, India: preliminaryevidence on their role in seed germination and dispersal S. Sathyakumar1'3 and S. Viswanath2'4 food and feeding habits of the Malayan sun bear (Helarctos malayanus) in Central Borneo, Indonesia, 1WildlifeInstitute of India,P.O. Box 18, indicated that this species could be an importantseed Chandrabani,Dehradun 248 001, India dispenser depending upon the species consumed, 2Instituteof Forest Genetics and Tree Breeding, numberof seeds ingested, and the deposition site. Forest Campus, Coimbatore641002 India Asiatic black bears are well known seed predators. that acorns Key words: Asiatic black bear, food habits, germination Manjrekar(1989) reported (Quercus robur) and walnuts were crushed tests, seed dispersal,seed germination,seed predator, (Juglans regia) totally by black bears while on them, Symplocos theifolia, Ursus thibetanus feeding thereby hindering Ursus14(1):99-103 (2003) dispersal. Black bears were also reported to feed on seeds fallen on the ground,and signs of regenerationof species, walnut in particular,were reportedto be low. We presentobservations on the food and feeding habits In India, the Asiatic black bear (Ursus thibetanus) of Asiatic black bearand observationson germinationof occurs in forested habitats of the GreaterHimalaya at bear food plants in Kedarath Wildlife Sanctuary(WS), 1,200-3,000 m elevation (Sathyakumar2001). Informa- Western Himalayaduring 1989-92. tion on the feeding and movement patternsof Asiatic black bear in India is limited to 2 short studies (Manjrekar1989, Saberwal 1989) and some observa- Study area tions by Schaller (1969), all in Dachigam National Park Kedarath WS (975 km2) is located in Uttaranchal, (NP) in Jammu and Kashmir,India. The Asiatic black NorthernIndia, at elevation that varies from 1,200 to bear in India is an omnivore, but feeds mainly on fruits 7,068 m. It lies in the upper catchmentsof Alaknanda and leaves of a few plant species. its Consequently, and Mandakini rivers (30?25'-30?45'N, 78055'- movement depends largely on the density and distribu- 79?22'E), major tributariesof Ganges. Kedarath is tion of these key food plants in the area. In addition, influenced by the southwest monsoon in summer and food production is known to play a major role in by the passage of belts of low pressurein winter (Mani reproductionof American black bears (Ursus ameri- 1974). The major vegetation types include sub-tropical canus; Jonkel and Cowan 1971). In Dachigam National pine (Pinus roxburghii), temperate broad-leaved oak Park (NP), India, when fruits were available, a major (Quercus leucotrichophora,Q. glauca, Q. floribunda) proportionof Asiatic black bear diets were composed and associated species, sub-alpineoak (Q. semecarpifo- initially of sugar-richfruits, followed by fat-rich fruits lia), fir (Abiespindrow), birch (Betula utilis)-rhododen- before hibernation(Manjrekar 1989). dron (Rhododendroncampanulatum), and alpine scrub, There are few studies available on feeding habits of meadows, and pastures.The status of Asiatic black bear other bear species and theireffects on seed germination. in Kedarath WS has been reportedas 'rare' Traveset and Willson (1997) discussed effects of some (Sathya- kumar2001). Most of the observationson Asiatic black birds, American black bear, and brown bear (Ursus bear and its food habits were made in an intensive study arctos) on seed germinationof fleshy-fruitedplants in area (20 km2; 1,700-3,680 m) near Mandal, located at temperaterainforests of southeast Alaska. Their results the southern boundary of Kedarnath (Sathyakumar indicated no difference in germinationrates for seeds 1994). that passed throughthe guts of captive birds and black and brown bears; they reportedthat the advantagesof seed dispersallie more in seed movementaway from the parentplant than in seed treatmentwithin the dispens- Methods er's gut. McConkey and Galetti (1999), while reporting We made casual observationson Asiatic black bear food and feeding habits during 1989-92. During direct sightings, informationon habitatuse and activity were recorded.If feeding was observed, data on food plants 3email: [email protected] [email protected] were recorded. Indirect observations such as scats, 99 100 SHORTCOMMUNICATIONS feeding sign, and tracks were also used to collect (Panthera pardus). We had indirect observations of informationon black bear habitatuse, food, and feeding bears such as feeding signs and remains in scats of habits. An inventory of bear food plants was prepared acors of oak (Quercus leucotrichophora,Q. semecar- based on fresh feeding signs and remnantsof undigested pifolia.), montanebamboo (Arundinariafalcata, Tham- plant materialidentified in their scats. We also recorded nocalamusspathiflorus), fruits and berriesof Symplocos informationon black bear food habits providedto us by theifolia, and insects. Secondary information from wildlife staff and villagers. several forest staff and local villagers indicated that In October 1990, 2 bear scats with intact seeds were black bears also feed on Juglans regia, Prunus cornuta, encounteredin the Mandal area at 1,900 m and were Myrica nagi, Aesculus indica, Rubus elipticus,Fragaria transportedto the Forest Research Institute,Dehradun, indica, and cultivatedcrops like maize and amaranth. for testing. The scats were washed thoroughly in runningwater and the entire intact seeds of Symplocos Germination studies of S. theifolia theifoliawere separated(they could be easily recognized Freshly maturedS. theifolia seeds were dormantand in the scat, especially the blue remnantsof the outercoat did not germinateuntil the 3rdweek in the laboratory of fruit/berry). At this same time, we collected freshly tests. In contrast,the matureseeds with pulpy outerlayer matured fruits (berries) from standing trees of S. (control) showed very little signs of germination and theifolia from the study area. The mature fruits were deteriorated very fast at both temperatureregimes. depulpedby hand and seeds extracted.Some fruits were Observationsin the laboratoryshowed increased ger- left whole and kept as a control. All fruits and seeds mination of seeds that were ingested by bears when retrievedfrom the scat were stored for 3 weeks at 5?C. compared to control and freshly depulped seeds sub- The seeds were then tested for germinationby allowing jected to the same germination treatments (Fig. 1). them to sit in moist filter paper in petri dishes. Three The proportionof seeds that germinatedfrom the bear than the replicates of 25 seeds each were used for each of the scat kept at 25? was significantly higher pro- 3 test conditions: seeds from bear scat, from depulped portion that germinatedfrom the depulped seeds kept = mature fresh fruit, and from whole fruit (control). All at 25? (2-sample t 3.29, 34 df, P < 0.002). Under the seeds took 5 months samples were exposed to 2 different temperatureand field nurseryconditions, nearly = 153 SD = with light regimes using incubators:(1) alternating(12 hr at to germinate(x days, 5) poor germi- 25?C with 12 hr at 10?C) and (2) constant 25?C. The nation percent (22%; Table 1). alternatingtemperature regime approximatedthe mean daily maximum and minimum temperatures at the Mandal study area during spring (Mar-Apr). The petri Discussion dishes were moistened regularly and observations on Black bear feeding habits were germinationwere noted at weekly intervalsfor 6 weeks. Manjrekar(1989) reportedthat 22 food items Seeds with emerged radicles were considered germ- found in the diet of black bears in DachigamNP, May- inated and removed from petri dishes. October,based on scat analysis. Over 22% of the overall and about Separately, we also conducted germination tests in diet by weight was foliage, 72% was fruit, field nurseriesin Mandal on S. theifolia seeds collected 2% was animal matter.Prunus avium and Morus alba in from standing trees (Table 1). In field nurserieswithin (mulberry)were the majorfruits in the diet June-July, and the study area, mature whole fruits of S. theifolia col- while Quercus robur (English oak) Juglans regia lected in Octoberwere sown in Novemberin uncovered, (walnut) accountedfor a majorproportion of the diet in Schaller raised germinationbeds (1.5 m X 10 m X 0.3 m) filled September-early October (Manjrekar 1989). with soil, sand, and compost. For S. theifolia, 100 fruits (1969) investigatedthe diet of black bears in Dachigam on scat Oak (4 replicationsof 25 each) were sown. NP during Octoberbased analysis. (12%), walnut (33%), and Celtis australis (40%) formed the major diet of black bears. Schaller also observed bears Results feeding on fallen oak acors and walnuts. Black bear feeding habits Oak acorns constitute an importantdietary item in We observedblack bears on 6 occasions and collected bear food habit.Four species of oaks have been recorded and 20 scats (Table 2). Bears were observed feeding on in the study area: Quercus leucotrichophora Q. Rhododendron arboreum, Berberis asiatica, and on glauca at lower elevations (1,600-2,000 m) and Q. the remains of a cattle kill made by a common leopard floribunda and Q. semecarpifolia at the mid- (2,000- Ursus 14(1):99-103 (2003) SHORTCOMMUNICATIONS 101 Table 1. Germination data of some tree species tested in forest nurseries in Mandal. Seed characteristics S.No Species Life forma Seed type GGb SODC MOSd n GCe I ., , , 1. Abies pindrow ct cone ID DS 12 100 3 2. Acer caesium ct samara ID DS 11 100 4 3. Acer caudatum ct samara ID DS 11 100 4 4. Acer oblongum ct samara ID PR 4 80 3 5. Acer sterculiaceum ct samara ID DS 11 100 3 6. Aesculus indica ct capsule ID DS 11 100 2 7. Alnus nepalensis ct winged nutlet ID PR 7 100 4 8. Berberislycium us berry DR RS 8 100 2 9. Betulaalnoides ct winged nutlet ID PR 7 100 2 10. Buxus wallichiana us capsule ID DS 10 100 4 11. Caesalpinadecapetala us pod ID PR 5 40 3 12. Carpinusviminea ct winged nut ID DS 9 100 3 13. Daphnepapyracea us berry RR RS 6 100 2 14. Daphniphyllumhimalaense ct berry ID DS 10 100 3 15.