STATUSOF BROWNBEARS IN KAMCHATKA,RUSSIAN FAR EAST IGORA. REVENKO,Kamchatka Ecology Institute,Russian Academy of Science, Rybakov19a, PetropavlovskKamchatskiy, Russia, email: [email protected] Abstract: The KamchatkaEcology and Nature ManagementInstitute has been censusing brown bears (Ursus arctos) in the southernpart of the Kamchatkapeninsula (Russian Far East) since 1991. The censused area comprised 11,045 km2within the districtsof Yelizovo, Ust' Bolsheretsk, Sobolevo, and Ust' Kamchatsk. We used an aerial total count method while flying in small fixed-wing planes duringlate spring (May-early Jun) to collect data on bear numbers,their distribution,den location, birthrate, and cub survival. A total of 1,051 bears was observed during 83 hours of overflight time during 1991, 1993, and 1994. Our yearly estimates of average bear densities in the southernpart of Kamchatka(54,100 km2 study area)ranged from 0.81 to 1.30 bears/10 km2. Some areashad high bear density (>1.7 bears/10 km2)despite huntingpressure. Bear numbers declined (<0.8 bears/10 km2)near settlementsalong main roads. The main threatto brown bears in Kamchatkais poaching for bear partsby local residents. We recommend that aerial censuses be expanded and improved to more accuratelyestimate population status and trends. Alternate means of employment in ecotourism and outfitting should be developed for local residents to encourage their support of measures to sustain Kamchatka'sbrown bears. Ursus 10:11-16 Key words: aerial census, brown bear, density, Kamchatka,Russia, Ursus arctos. In 1991 the KamchatkaEcology and NatureManage- Our study was done in 84,600 km2of the southeastpart ment Instituteinitiated a study on the status and dynam- of the peninsula, a mountainousarea divided by broad ics of the brown bear populationin Kamchatka,Russian river valleys with most peaks reaching 1,500 m of eleva- Far East. Prior to that time wildlife authorities in tion (Fig. 1). The study area is a very active volcanic Kamchatkahad insufficientdata aboutbrown bear popu- zone that includes >20 volcanoes (1,900-5,850 m eleva- lations to manage them, including estimates of the num- tion). The long coastline consists of steep banks, cliffs, ber and distributionof bears or knowledge of habitatuse, and beaches. More than 95% of the human population recruitment,and survivorship. Ostroumov (1968) esti- and all majorcities are along the coast. These centers of mated Kamchatka'sbrown bear populationto be 18,000 humanactivity are servicedby only 2 main roads, with a to 22,000 in the early 1960s. Dunishenko (1987) esti- total length of approximately1,000 km. mated a populationof 12,000 to 14,000 bears in the late The vegetationcover on Kamchatkais very dense and 1960s. Accordingto an official reportof Kosheev (1991) mainly consists of pine (Pinuspumila) and alder bushes there were 8,000 to 10,000 bears in Kamchatkain 1986- (Alnus kamtschatika)from the coast to 1,200-1,300 m 90. These estimates described a downward trend in above sea level, stone birch (Betula ermanii) forests on Kamchatka'sbrown bear population. In the late 1980s lower slopes to 700-800 m elevation, and willow (Salix and early 1990s brownbears also faced increasedpoach- undensis) and cottonwood (Populus komarovii) forests ing. Worsening economic conditions in Russia forced along drainages. The rugged terrainand lush vegetation authoritiesand natureconservation agencies to pay less provided high security cover for bears during the en- attentionto brown bears. These developmentsincreased tire snowfree period. Approximately half the study the need for more accurateinformation on Kamchatka's area (46.7%) provided bears with a variety of foods brown bears. Consequently,we initiatedthis aerial sur- (e.g., grasses, salmon [Oncorhynchus spp.], berries, vey to estimate the density of bears in this population. and pine nuts), protection, and den sites (Table 1) For help during this project I thank: A. Kovalenkov, (Revenko 1993). These high quality bear habitatshave V. V. Kudryavtsev, Martynov, V. Mosolov, A. helped bears to maintain their number through a long and V. Gordienko. Nikonorov, history of bear-human relations. Moderate quality bear habitats (6.3% of the study area) lacked food di- versity, good denning sites, and There are STUDY AREA protection. many settlements and logging activity within this area. Kamchatkais a 1,200-km long peninsula in the Rus- Low quality bear habitats on 47% of the study area sian Far East bounded the by Sea of Okhotsk,the Bering provide limited food resources and had little protec- Sea, and the Pacific Ocean. Its maximum width is 440 tion for bears. km, and area is km2. Brown 472,300 bears occupy ap- Two nature preserves comprise 14% of our study proximately 81.3% (384,200 km2) of the Kamchatka area: Kronotskiy State Preserve and South Kamchatka almost Peninsula, without fragmentation(Anon. 1995). Sanctuary. Bear hunting has been prohibited within 12 Ursus 10:1998 Fig. 1. The study area (withindotted line) for aerial surveys of brown bears in southeastern KamchatkaPeninsula, Russia, 1991. Shaded areas include bear preserves. their bordersfor the last 20 and 10 years, respectively. we spent 2 years studyingbear activity in differentparts Bear huntingis permittedin the rest of the study area. of the study area and the effect of snow conditions on bear activity and our ability to detect activity. Due to the high visibility of bears and their tracks on snow, we METHODS chose early May to early June for aerial surveys. We We conducted aerial strip counts of bears during the tried to time our surveys to coincide with the 1-2 weeks late springof 1991, 1993, and 1994 to estimatebear den- duringwhich most bears emerged from their dens while sity, distribution,and birth rate. Prior to these surveys snow was still present. Weatherpermitting, we tried to BROWNBEARS IN KAMCHATKA * Revenko 13 Table 1. Extentand qualityof habitattypes occupied by duringthe 3 years of survey (Table 2). We recordedthe brownbears in Russia on Anon. Kamchatka, (based 1995). following data on a portabletape recorderwhile flying: flight date, time of day, weathercondition, percent snow Bear habitatquality, type Area, x 1000 km2 Percent cover, habitattype, and numberof bears seen. For each High quality adult bear we recordedsize, color, activity, and number Birch forest 64.2 16.7 and age of any offspring. For the census we did not count Willow forest 15.0 3.9 beartracks on snow as have previousresearchers because Dwarf pine shrub 74.0 19.3 it resultedin biases in We counted tracks Alder shrub 26.0 6.8 extrapolation. Subtotal 179.2 46.7 of females with cubs and yearlingsto estimatebirth rate. The time spentconducting surveys for any year depended Medium quality on the available funds for aircraftrental. Larch forests 14.1 3.7 The of bearsin the areawas estimatedas Spruce forests 2.2 0.6 density study Clearcuts, burs 7.7 2.0 follows: density of bears = bears observed in transect/ Subtotal 24.0 6.3 area of strip transect. I applied area-specificcorrection factors to account for the different of bears Low quality sightability Flat tundraand swamps 125.0 32.5 undervarying conditions of snow cover, terrain,weather, Mountain tundra 56.0 14.5 andtime of the day. The factorrepresented an averageof Subtotal 181.0 47.0 the sightabilityof bears over the yearly survey. To com- Total 384.2 100.0 putethe averagesightability we assumedthat we observed 80% of the bears in birch forests on steep mountainous time our surveys to occur when bears were most ac- slopes, 90% in less brokenterrain, and all bears on open tive. Our preliminary study revealed that to be 0700- snow covered surfaces on sunny days. We did not con- 1000 hours and 1700-2200 hours. duct aerial surveys duringcloudy weather. To compare During 1991 we used a 10-passengerplane (AN-2) and beardensities within the study areawe divided the region an 18-passengerhelicopter (MI-8) which were the stan- into zones. Each zone representeda homogeneousland- dard vehicles for aerial surveys in Kamchatkauntil the scape with respect to the quality of bear habitatand hu- early 1990s. In 1993 and 1994 we used a small fixed- man occupation. The bear density for a zone was the wing Polish plane (3 passenger, Vilga-35) and a small mean numberof bearsobserved/10 km2 of transectflown helicopter(6 passenger,MI-2). In 1991 we surveyedthe within the zone. Lastly we asked residents about their Yelizovo and Bol'sheretsk districts. We also surveyed attitudestoward bears to understandthe main threatsto the Ust'-Kamchatskand Sobolevo districtsduring 1993 bears from humans. and 1994. Withindistricts we avoided open coastal flats with tundrasand wide swampsand mountains higher than 1,500 m because brown bears do not use these areas in RESULTS spring. We flew mostly over forests, shrub lands, and We observed a total of 1,051 bears during83 hours of mountaintundra. We did not fly in a straightpath but overflightsduring 1991, 1993, and 1994 (Table 2). Esti- followed the major geographicalfeatures such as main mateddensity was 0.81 bears/10km2 in 1991, 1.30 bears/ rivers, ridges, and coastline. 10 km2in 1993, and 1.13/10 km2bears in 1994. Most of We observed bears from aircraftduring strip transect these bears we observed either in mountainousterrain surveys; sightings were used to estimate the total num- between 300 and 1,100 m elevation or in birch forests or bers and density in each study area. The strip width was aldershrubs along the Pacific coast. Very few bearswere 1-km wide when observerscould see the groundon both seen on open, low elevation areas. Fresh grasses along sides of aircraft,or 0.5-km wide when there was 1 ob- the coast or river banks appearedto attractbears begin- serveror when the plane was flying along the coast. We ning in late May. Most of the bears observed in June flew 150 m above the groundat speeds of 140-160 km/ were feeding on fresh grasses along river banks.