Movements and Distribution of Radio-Collared Caribou in the Buckland Valley and Nulato Hills, Winter of 1989-90
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u. S. Department of the Interior 8 Bureau of Land Management Alaska State Office ~ 222 West 7th, #13 y Anchorage, Alaska 99513 Movements and Distribution of Radio-Collared Caribou in the Buckland Valley and Nulato Hills, Winter of 1989-90 Scott R. Robinson and Mary Leykom 1!l~IMlQtADt!l@)~t!l @fFJ@1lU IFBD@ OO@~@)r~ ~~. March 1991 Authors Scott R. Robinson, Bureau of land Management, 1150 University Avenue, Fairbanks, AK 99709. Mary Leykom, Bureau of land Management, P.O. Box1049, Kotzebue, AI< 99752. Open File Repons Open File Reports identify the results of inventories or otherinvestigations that are made available to the public outside the formal BlM-Alaskatechnical publication series. These reports caninclude preliminary or incomplete dataandarenot published anddistributed inquantity. The reports areavailable at BlM offices in Alaska, the USDI Resources Library inAnchorage, various libraries of the University of Alaska, andother selected locations. Copies arealsoavailable for inspection at the USDI Natural Resources Library in Washington~ D.C., andat the BlM Service CenterLibrary in Denver. Movements and Distribution of Radio-Collared Caribou in the Buckland Valley and Nulato Hills, Winter of 1989-90 Scott R. Robinson and Mary Leykom Bureau of Land Management Open File Report 33 Alaska State Office March 1991 Anchorage, Alaska 99513 Table ofContents Page Introduction 1 Study Area 1 Methods 4 Results 4 Caribou 4 Reindeer 8 Discussion 8 Recommendations 9 Literature Cited 10 BLM-Alaska Open File Report Series 11 List of Figures Figure 1 2 Figure 2 3 Figure 3 5 Figure 4 6 Figure 5 7 List ofTables Table 1 4 INTRODUCTION cooperating agencies in this study. Each agency funded their respective share of the work. With a minimum count of 343,000 caribou (Rangifertarandusgranti) in 1988,theWestern Objectives of this project were: (1) to document Arctic Herd is the largest in Alaska and ranges seasonal migration patterns and winter range of over the northwest quarter of the state. This western arctic caribou in the Buckland Valley herd has continued to increase in size since and Nulato Hills, (2)to monitor the caribou with 1976, when the population was estimated at respect to adiacent reindeer herding activities, 75,000 animals (Larsen et al. 1990). Parallel and (3) to make information concerning caribou expansion into previously unoccupied winter distribution and movements available to the range has also occurred since 1976. Presently, public in a timely manner. the Western Arctic Herd is an important subsis tence resource to residents ofapproximately 30 rural villages. Moreover, people from through STUDYAREA out Alaska and elsewhere travel to northwest Alaska to view, photograph, and hunt caribou. Encompassing 6.3 million acres, the Buckland Valley and Nulato Hills comprise one of the In 1975, NANA Reindeer Enterprises filed an largest blocks ofBLM-managed land in Alaska. amended application to graze reindeer (R. t. This area is bounded on the north by the Selawik tarandus) in the northeastcorner ofthe Seward Hills, on the east by the Koyukuk and Yukon Peninsula. The Bureau of Land Management rivers, onthe south bythe UnalakleetRiver,and (BLM) issued a grazing permit to NANA for a on the west by Norton Sound and the Seward maximum of5,000reindeer(BLM1976).Nathan Peninsula (Fig. I), Four domestic reindeer graz Hadley ofBucklandandDougSheldon ofCandle ing allotments overlap the study area (Fig. 2). have held grazing permits in this area since The Buckland Valley is broad, whereas the 1987. The Henry family of Koyuk has grazed Nulato Hills have rounded summits with gentle reindeer in the Koyuk drainage since 1962; slopes dropping into narrow valleys. Elevation Merlin Henry has herded 800 reindeer since ranges from sea level to 3,411 feet atop Debauch 1981. BLM (1986) prepared an Allotment Man Mountain in the Nulato Hills. agementPlan(AMP)forhis herd. The Sagoonick family of Shaktoolik has grazed reindeer along Regional climate is characterized by severe Norton Sound since 1968; the present herd has winters from October to April and cool, wet, an estimated 1,400 reindeer. BLM (1990) also windy summers. Normal winter temperatures prepared an AMP for the Sagoonick herd. All range from -20 F to +10 F with extreme lows of four reindeerallotmentsfall within winterrange -50 F to -60 F. Annual precipitation averages of western arctic caribou. less than 15inches, includinglessthan50inches ofsnow.Snowdepthsontheground vary because Caribou and reindeer using the same rangeland of drifting. The average wind speed is 11 knots have never been compatible(Shideleret a1. 1986). year-round. Weather patterns can prevent air When ranges ofthese two populations (wildand craft from flying for several consecutive days domestic) overlap, resident reindeer link with (Selkregg 1977). transient caribou and leave their grazing allot ments. Adams (1983) prepared a Habitat Man The areas lowest in elevation are characterized agement Plan (HMP) because of this dual use by graminoid vegetation, whereas higher, well conflict between caribou and reindeer in the drained slopes are covered by low shrub scrub. BucklandValley.This studyincludedthe Nulato The hills and mountains are covered by black Hills because western arctic caribou expanded spruce (Picea mariana) at lower elevations with their winter range southward into other rein graminoid and low shrub scrub above tree line. deer allotments in recent years. This report Tall willows(Salix spp.)andwhite spruce (Picea partiallyimplementsthe Buckland ValleyHMP. glauca) line the riparian zone, and several spe Results from previous caribou surveys for this cies of lichens grow throughout the study area. area were reported by Adams and Connery (1983),Smith (1984, 1985),Smith and Machida Key wildlife species in this area are caribou, (1986), Robinson and Field (1987), Robinson moose CAlces aloes), grizzly bear (Ursusarctos), (1988), and Robinson and Spindler (1989).The and wolf(Canus lupus). A variety offurbearers, Alaska Department of Fish and Game (ADFG) waterfowl, small game, and nongame species and U.S. Fish and Wildlife Service (FWS) were are also present. A detailed description of the 1 River fiGURE I Buckland Valle., Mister 1 HlbUat ManaQement Plln Arel 0 SEWARD PENINSULA lOCAT ION MAP Figure 1 2 River SEWARD PENINSULA FIGURE 2 REINDEER ALLOTMENTS Sbeldon [>U+>/J Hodleg ~, Henrg iii I SOQoonlCk • I Figure 2 3 study area can be found in the Buckland Valley caribousurveys. The outsideborderencompasses Habitat Management Plan, theNorthwest Unit all caribou located during the indicated flight.. Resource Analysis, and the Central Yukon Re All of the reported mileage figures are consid source Management Plan (Adams 1983, BLM ered as a minimum distance traveled. Since the 1982, 1986). caribou were not monitored daily, these figures represent only a measurement of distance be tween two location points. METHODS Between September 4 and 11, 1989, ADFG per RESULTS sonnel captured and fitted 32 caribou with ra dio-collars as they crossed the Kobuk River at Caribou Onion Portage. This collaringeffort brought the total number of caribou fitted with functioning Three surveys were flown between October 4 collars to approximately 112 animals. Thirteen and 11, locating 59 caribou; some animals were radio-tracking flights over part or all of the locatedmore thanonce.Aftercrossingthe Kobuk Buckland Valley and Nulato Hills were con River, the majority of caribou moved south and ducted from October 4, 1989 to March 26, 1990 west through the Selawik River valley to the (Table 1). Flights were flown as high as 10,000 Buckland River valley, where a large aggrega feet with either a Cessna 185 or 206 travelingat tion occurred. Sixty-eight caribou were located cruising speed. Locations of individual animals during three surveys flown October 20, 26 and were recorded, mapped, and later transferred to November 6. During this period, the animals a dBase III Plus file for storage on a personal moved near the southern extent of their winter computerattheADFGofficein Kotzebue. Loca migration. Three caribou were located east of tions of reindeer were also noted whenever Shaktoolik Village and one on the North Fork of possible. Locations were described by general the Unalakleet River (Fig. 3). areas within river drainages and, whenever possible, by township and range of the public The November 28-29 survey located only 11 land rectangular system of survey (BLM 1979). animals because of incorrect programming of the radiotelemetry receiver, but observations Shaded areas on Figures 3-5 correspond to two did show a continued southward migration. The different time periods depicting one or more Table 1. Aerial surveys of'radio-eollared caribou across Buckland Valley and Nulato Hills, Winter of 1989-90. Flight Total number number Survey date relocations Agency Observers 4 River fiGURE 3 , Surveys 10/4 through ~T ~I 10/11/89 Surveys 10/20 throufJh ~ 11/6 189 SEWARD PENINSULA 6 12 18 24 30 ! t SCALE IN MILES Figure 3 5 River FIGURE 4 j Survey 11/28 & ,.1 29189 Surveg 12/20189 LId SEWARD PENINSULA 6 12 18 24 3C ! ! I SCALE IN MILES Figure 4 6 I R;ver FIGURE 5 , Surve~ 1/18 & 28 2/19190 _I Surve~ 3/26190 • SEWARD PENINSULA 6 12 18 24 30 , , , , I SCALE IN MILES Figure 5 7 December 20 survey located 30 radio-collared until April 1990. He estimated a loss of at least caribou and observed more caribou continuing 100reindeer to caribou that occupiedhis permit to move south from the Tagagawik River and area throughoutthe winter. He estimated4,OOO~ Buckland Valley to the Inglutalik, Ungalik and 5,000 caribou resided along the East Fork ofthe Shaktoolik rivers (Fig. 4). Most caribou located Koyuk River. Because 'of the heavy concentra in the November surveys were relocated in De tions of caribou, Mr. Henry was unable to move cember. One animal ranged more than 60 miles hisreindeer into the southeastern portion ofhis north, while anotherwas relocatedjust 15miles permit area as was planned for the winter of from the previous survey.