HOMERANGE AND HABITATUSE OF BROWNBEARS IN THESOUTHWESTERN OSHIMA PENINSULA, HOKKAIDO TSUTOMU MANO, Institute of Applied Zoology, Faculty of Agriculture, Hokkaido University, Sapporo 060, Japan Abstract:Movement, home range, and habitat use of 10 (7 M and3 F) brownbears (Ursus arctos yesoensis) were investigated by radiotracking in southwesternOshima Peninsula, Hokkaido, from May 1987 through May 1990. Theannual home-range size was 28.1-39.1 km2for 1 female. Malehome-range size was largerthan that of females,although no maleswere monitored throughout the year. Lowerdeciduous natural forest areassuch as beech-oak(Fagus crenata)-(Quercus monoglica var. grosseserrata)forest and maple-linden (Acer mono)-(Tilia japonica) forest were used by bears intensively,but subalpineareas such as sasa-birch(Sasa kurilensisor S. senanensis)-(Betulaermani) forest and sasa communitywere rarelyused andusage was restricted.Food availablilty could influence the habitatselection by the bears. Int. Conf. Bear Res. and Manage.9(1):319:325 Hokkaido brown bears have been killed Yamazaki,T. Tsuizuki,G. Suzuki,N. Sato, T. Sato, indiscriminatelyfor more than 120 years. Especially and K. Takahashi,who are the members of the duringthe period of 1966 through1989, the spring HokkaidoHunting Society, kindly cooperated with the prophylactickilling system was in force, and many study. T. Tsubota,K. Yamamoto,Y. Kamada,and the bearswere killedas pestsand as gameanimals. Forest members of the Brown Bear Research Group of and field areas have been developed without Hokkaido University also provided devoted field considerationsof bearhabitat maintenance. As a result assistance. Y. Sawamuraand K. Kudo provided of these pressures, conspicuousextinction or near assistancein aerial radio location. The Matsumae extinctionhad occurredby the 1980s in northern DistrictForestry Office of Hokkaidoalso gave facilities Hokkaido(Aoi 1990) andin areassuch as the Shakotan for investigations.K. Kanagawacooperated with the Peninsulaand the Yoichidake-Eniwamountain area English. Thisresearch was partlyfunded by the Japan (HokkaidoGovernment 1986). However,recent bear EnvironmentalAgency. Asahi BroadcastingCo., damageto livestockand crops still occurs in otherparts IwanamiProductions Inc., and Tokyo Broadcasting of Hokkaido(Hokkaido Government 1986). It is SystemInc. also providedfinancial assistance. obviousthat with the controlkill alone, damageswill continueto occuruntil the bear population drops to near extinction. STUDYAREA Sincemid 1970, aboutone-fourth of the totalbrown The studyarea occupies about 300 km2and is located beardamage in Hokkaidohas occurred (annually) in the in the northwesternpart of MountDaisengen, which is OshimaPeninsula (Hokkaido Government 1986), which the highest mountainof the southwesternOshima occupiesonly about9% of the island. As this areais Peninsula(Fig. 1). Elevationranges from sea level to a peninsula, characterizedby having a very long the top of MountDaisengen, 1,072 m. Most of this boundarybetween bear range and humanresidential areais steepmountain ranging between 200 and600 m areas,troubles and conflictsbetween people and bears in altitude. Maritimetemperate climate brings annual areapt to occur. Moreover,habitat development on the precipitationof about 1,209 mm and average OshimaPeninsula could have a majorinfluence on bear temperatureof -1.2?C in Februaryand 22.2?C in habitat and populationmaintenance on Hokkaido. August,in Esashi,which is locatedon the sea coast 10 Biologicalinformation such as brownbear home range km north of the study area (JapanMeteorological and habitat use is required for proper habitat Agency 1983). Snow cover remains from mid management. Decemberto late May in the higherarea and from late The firstsuccessful brown bear radio-telemetry study Decemberor earlyJanuary to earlyApril in the lower in Hokkaido, Japan, was initiatedin southwestern areaalong the sea coast. OshimaPeninsula in 1987. In this paper, I present The naturalvegetation of the majorpart of the study preliminaryinformation on movement,home range, and area is forest dominatedby beech (Fagus crenata), habitatuse of Hokkaidobrown bears in the deciduous mixedwith maple (Acer mono), linden (Tiliajaponica), forestof this area. oak (Quercus monoglica var. grosseserrata), and I thankK. Maitaand S. Kojimafor theirdevoted dogwood (Cornuscontroversa), with under cover of field assistance. I thankalso M. Yoneda,H. Abe, T. sasa bamboo (Sasa kurilensis or S. senanensis), castor Aoi, H. Kudo, andT. Akasakafor theirhelpful advice aralia (Caphalotaxusharringtonia), and spice bush and suggestions. Y. Maruko, A. Kishikawa, J. (Lindera umbellata var. membranacea). This 320 Int. Conf.Bear Res. and Manage.9(1) 1994 METHODS Brown bears were captured in barrel traps baited with 1 kg honey (Mano et al. 1990), then immobilized with ketaminehydrochloride and xylazine hydrochloride (Tsubota et al. 1991), weighed, and measured. A lower fourth premolar tooth was extracted for age determination by counting cementum annual layers (Craigheadet al. 1970). Every bear was equipped with 144 MHz radio collars (Lotek, Inc., Aurora, Ontario) and plastic ear tags. Radio locations of instrumented bears were made daily when possible by triangulation from the I used a 3-element antennaand SEAOF ground. Yagi a FT290-mkII receiver (Yaesu Musen, Inc., Tokyo). Aerial radio locations (3 times by fixed-wing airplane and 2 times by helicopter) were made when bears were missed from the ground. Bear locations were recorded on 1:50,000 scale topographicalmaps. The vegetation type of the radio locations was recorded by the same scale used in the Actual Vegetation Map (Japan Environment Agency 1984). Home-range size was calculated from the polygon defined by connecting the outermost radio locations (Mohr 1947). The expected frequency of radio locations by vegetation type when home range was used uniformly was calculated by multiplying the total number of the radio locations by the percentage of each within the home Fig. 1. Brown bear study area in southwestern Oshima vegetationtype range. Vegetation Peninsula, Hokkaido. The polygon shows the outmost of the preference of bears was examined by comparing the trap sites. expected and actual frequency. The mention of vegetation types was according to legend of the Actual vegetation type is abbreviated as SBF. As the Vegetation Maps of the Environmental Agency. substantialforest of this vegetation type, beech and oak Abbreviations of each vegetation type are shown in forest (BOF) is found in relatively lower areas. On the Table 1. I used G-test to determine significance in slope along the sea coast, maple and linden dominant comparing. forest mixed with oak is found. This vegetation type is abbreviated as MLF. The area near the ridge and higher than 600 m in altitude is occupied by birch RESULTS (Betula ermani) stands with sasa bamboo under cover. In 12 capturesbetween May 1987 and October 1988, This vegetation type is abbreviatedas BF. The highest 11 brown bears (7 M, 4 F) were capturedand 10 bears area over 800 m in altitude is a sasa bamboo (7 M, 3 F) were instrumentedwith radio collars. Only community with Sasa spp. and alder (Alnus crispa). 1 female bear (No. 3) was monitored for 33 months in This vegetation type is abbreviatedas SC. White pine succession. Estimation of annual home range was (Pinus pentafira var. himekomatu)is found on the steep available for this female bear in 1988 and 1989. As rock ridge. Along the riverside, forest of horse other individuals were continuously contacted from 4 chestnut (Aesculus turbinata), wingnut (Pterocarya days to 10 months, seasonal home ranges, but not rhorifolia), elm (Urmus laciniata), and willow (Salix annual ones, of those bears were estimated. The spp.) is found. Conifer plantation (CP) of fir (Abies reasons for interruptionof tracking were 2 losses of sacharinensis), Japanese cedar (Cryptomriajaponica), radio collars, 2 control kills, 2 troubles with radio and larch (Larix kaempheri)is found in relativelylower transmitters, 1 poison kill, 1 unknown death, and 1 areas. In the northern part of the study area, conifer large movement. I obtained 687 radio locations for all forest of hiba (Thujopsis dolabrata var. hondai), is bears. Habitatpreference was examined for the bears found regionally. No. 3, No. 6, No. 9, and No. 10. Radio locations of BROWNBEARS ON HOKKAIDO * Mano 321 Table 1. Abbreviationof vegetation types in the study area. Each name of vegetation type was according to legend of the Actual Vegetation Map of "KAMINOKUNI"and "DAISENGENDAKE"by the Japan EnvironmentAgency (1984). Vegetationtype Abbreviatename Vegetationin Vaccinio-Piceetea(subarctic or subalpine)Region Sasa spp. community Sasacommunity (SC) Betulaermanii community Birchforest (BF) Sasa spp.-Betulaermanii community Naturalvegetation in Fageteacrenatae (cold temperate)Region SasetoKurilesae-Fagion crenae Sasa-beechforest (SBF) Acermono var. glabrum-Tiliajaponica community Maple-lindenforest (MLF) Substitutionalcommunities in Fageteacrenatae (cold temperate) Region Fagus crenata-Quercusmongolica var. grosseserratacommunity Beech-oakforest (BOF) Plantcommunities in clear-cutarea Clear-cutarea (CCA) Plantation Cryptomeriajaponica, Chamaecyparisobtusa, Chamaecyparis Coniferplantation (CP) pisiferaplantation Abiessachalinensis plantation Deciduousconifer plantation CulturalLand Field Weedcommunities in uncultivatedfield Culturalland (CL) Cultivatedmeadow No. 6 during2-22 October1988 wereexcluded for the Onlythe annualhome-range size of femaleNo.