SNOWCREEKSKI AREA DEERSTUDY 1994SPRING AND FALL MIGRATION STUDY

heparedfor:

DempseyConstruction C orporation P.O.Box 657 MammothLakes, CA 93546 6191934-6,861

hepared by:

TimothyTaylor & Associates P.O.Box l9l JuneLake, CA93529 619t648-7227

I\,larch1995 Tableof Contents

Page

Chapterl. Introductionand Methods...... l-l INTRODUCTTON...... l-l PERMITAREA...... 1.2 METHODS....,...... r-2 RadioTelemetry Studies...... L-2 RadioTracking ofDeer...... l-2 HoldineArea Studies...... 14 D-eerCounts Surveys...... 14 tlabitatUse Studies...... l-6 MigrationCorridor Counts...... 1-7 InfraredSensor Equipment ...... l-7 HabitatMapping...... l-7 WeatherData...... 1-7 ORGANIZATIONOF THISREPORT...... l-8

Chapter2. SpringMigration Surveys...... 2-l STAGE 1: MIGRATION BETWEEN THE WINTER RA}.IGE IN ROUNDVALLEY A}ID TI{E SFIERWINHOLDING AREA...... 2.1 Locationsof DeerMovements...... 2-l STAGE2: TIIE SHERWINHOLDING AREA...... 2-3 Timing andIntensity of DeerUse in the SherwinHolding Area...... 2-3 Radio-CollaredDeer...... 2-3 DeerCount Surveys...... 2-5 Estimatesof DeerAbundance in theSherwin Holding Area...... 2-10 Patternsof DeerHabitat Use in theSherwin Holding Area...... 2-14 DeerCount Surveys...... 2-14 Radio-CollaredDeer...... 2-19 Patternsof DeerDistribution in the SherwinHolding Area...... 2-19 STAGE 3: DEER MIGRATION BETWEEN T}IE SHERWIN IITOLDINGAREA AI{D TI{E SUMMERRA}.IGE...... 2.22 MigrationRoutesOvertheSierraCrest...... 2-22 MigrationRoutes Over the Sierra Crest-spring 1994...... 2-23 MigrationThroughtheSSAPermitArea...... 2-23 Migration Over SanJoaquin Ridge Hopkins Passand PiutePass...... 2-23 Summaryof DeerMgration Over the SierraCrest...... 2-23 Timing and Intensityof Migration throughthe Snowcreek Ski Area... . 2-24 RemoteDeer Counterc...... 2-24 Verificationof DeerCounter Accuracy...... 2-26 DailyTiming ofDeer Movements ...... 2-27

I SummerRanges of Radio4ollaredDeer...... 2-27 RoadKill Data...... 2-29

Chapter3. Fdl MgrationSurveys...... 3-l MgrationStudies...... 3-l Timing andIntensity of Mgration Ttrough the Snowcreek SkiArea...... 3-l Radio-CollaredDeer...... 3-l RemoteDeer Counterc...... 3-l Verificationof DeerCounter Accuracr'...... 3-l DaityTiming ofDeer Movements...... :...... 34 DeerComposition Counts...... 3-4 RoadKill Data:...... 34

Chapter4. Conclusionsand Recommendations...... 4-l

Chapter5. Acknowledgments...... 5-l

Chaper6.Citations ...... 6-l

Appe'ndix...... A-l Listof Fizures

Figure page l-l Locationof theSnowcreek Ski Area...... l-3 l-2 Locationof theDeer Count Survey Route in the SherwinHolding Area..... l-5

2-l Locationsof RoundValley Deer Herd MigrationRoutes, Mono County, California...... 2-z

2-Z CumulativePercent of Radio-CollaredDeer Arriving on andDeparting fromthe SherwinHolding during the 1994Spring Migration.. ...24

2'3 Periodof Delayfor IndividualRadio-Collared Deer on the SherwinHolding Areaand the SnowcreekSki Areaduring the 1994Spring Migration...... 2-6

2'4 CumulativePercent of Radio-CollaredDeer Arriving on andDeparting from the SnowcreekSki Areaduring the 1994Spring Migration...... 2-7

2-5 Total Numberof DeerCounted per Day duringDeer Count Surveys Conductedin theSherwin Holding Areq Spring1993 and 1994...... 2-8

2'6 TheTrend in SightingProbability on Group Sizeand the Numberof Deer Countedin the SherwinHolding Area during the 1994Spring Mgration.. ..2-12

Z-7 Percentof DeerObserved by VegetationType on the SherwinHolding Areaduring the 1994Spring Migration.. . 2-13

2-8 Locationsof DeerGroups Observed in the SherwinHolding Area duringthe 1993Spring Migration...... 2-16

2-9 Locationsof DeerGroups Observed in the SherwinHolding Area duringthe 1994Spring Migration...... 2-17

2'10 ConfidenceIntervals (95%) IndicatingMule DeerUse of Habitaton the SherwinHolding Area during the 1994Spring Migration...... 2-18

2'll Locationsof 237 Observuionsof 27 Radio-CollaredDeer in the Sherwin HoldingArea during the i994 SpringMgration...... 2-20

2-12 Numberof EventsCounted per Day by the Trailma.*erUnits at Solitude Pass,Spring Mgration 1994...... 2-25

lu Listof Figues(cont.)

Figure Page

2-13 Timing of Deer Movementsthrough the ProjectArea during Spring Migration1994...... 2-28

3-l Percentof Radio-CollaredDeer Crossing the SierraCrest in Relation to DailySnourfall Fall Migration 1994...... 3-2

3-2 Numberof EventsCounted.per Day by the TrailmasterUnits at Solitude Pass,Fall Migration 1994...... 3-3

3-3 Timingof Deer Movementsthrough the ProjectArea during Fall Migration1994...... 3-5

AppendixFigure 2...... A-2

AppendixFigure 3...... A-3

Tebles

2-l Meanpopulation estimates and ranges within 95% confidencelimits for muledeer counted on the Sherwinholding area during l0 deercount surveys conductedfrom April 7-June 9, 1994...... 2-l I

2-2a Utilization-availabilitydata for dominatehabitat types in the Sherwin holding area"Mammoth Lakes, California. Utilization datais basedon locationsof 160deer groups observed during l0 deercount surveys conductedduring spring 1994...... 2-15

2-2b Utilization-availabilitydata for dominatehabitat types in the Shenuin holding are4 MammothLakes, California. Utilization datais basedon locationsof 152deer groups observed during l0 deercount surveys conductedduring spring 1993...... 2-15

2-3 Utilization-availabilitydata for dominatehabitat types in the Sherwin Holding Area, MammothLakei California. Utilization datais based on237 visuEllocations of 27 radio-collareddeer observed in the Sherwin HoldingArea duringthe 1994spring migration...... 2-19

iv 24 Calculatedmule deer home range areas (hectares) for the Sherwinholding areaand the SnowcreekSh fuea usingthe minimumconvex polygon and adaptivekernel methods...... 2-21

2-5 Percentof radio-collareddeer that useddifferent migration routes over the Sierracrest, based on radiotelemetry data fiom Kucera( 1988)and spring1,994...... 2-23

2-6 Approximatetiming of deermovements through Solitude Canyon andover SolitudePass during the springmigrations of 1985-1989 and1993-1994 (Kucera 1985, Taylor 1988, Taylor 1994)...... 2-26

2-7 Locationsand habitats of 4 adultfemate mule deer observed in the SherwinSki Area between June 15 and June 30 1994...... 2-29

2-8 Deerfatalities recorded by Caltransduring spring and summer 1994...... 2-30

3-l Numberof deerclassified in the SnowcreekSki Area and surrounding vicinityaccording to sexand age during the 1994fall migration...... 3-4

v Chapterl. Introductionand Methods

INTRODUCTION

In June1994. Dempsey Construction Corporation (DCC) of MammothLakes. California,completed preparation of a DeerHerd Monitoring Plan (DHMP) (Raedeke Associates1994) for the proposedSnowcreek Ski fuea (SSA). TheFinal Environmental ImpactStatement (FEIS) for the SSA specifiedthat the DHMP be developedin orderto assessthe effectivenessof mitigation measuresdesigned to minimizeimpacts of the SSA on migratorymule deer,and to determinethe overalleffect of the SSA developmenton the RoundValley deer herd, formerly known as the SherwinGrade and Buttermilk deer herds.

The SSAis locatedimmediately south of the Townof MammothLakes (TML) on approximately3,100 acres of publicland managed by theU.S. Forest Service (USFS). Theproposed ski areaand surrounding vicinity is regardedas importanttransition range for mule deer(Odrcoileus hemiomtshemiomrs) from the Round Valley herd.which migratethrough the areaduring annualspring and fall migrations.

Throughoutthe past decade,the CalifomiaDepartment of Fish andGame (CDFG) hasbeen collecting data on the RoundValley deer population with emphasison factors affectingpopulation size and trend and habitatuse relationships. During the sameperiod, DCC hascollected site-specific data on the timingand locations of deeruse panerns in the proposedSSA permit areaand surroundingvicinity. The DHMP was designedto expand on this existinginformation and to furnishdata required by the SSA-FEISfor the analysis of potentialimpacts to migratorymule deer (Raedeke Associates 1994).

Thisreport summarizesfield studiescompleted by DCC duringthe 1994spring andfall migrations.Specific objectives of the springwork wereto: l) determine,through the useof radio telemetryand infrared sensorequipment, the amount,timing, andspecific locationsof migratorydeer use in the SSAand surrounding lands during the 1994spring andfall migrations;2) censusthe SherwinHolding Area (SIIA) usingdeer population estimatesbased on mark-recapturetechniques using radio-collared deer; 3) dwelop a *sigbtablity index" to estimatethe numberof deerin the holding areabased on the number of deerobserved during a given census;and a) determinehabitat use patternsby radio- collareddeer that use the SnowcreekSki Area and sunoundinglands. Objectivesof the fall work were to determinethe amountand timing of fall migratory deeruse and the specificlocations of deermigration routes.

The informationpresented in this report can be usedto rugment existing preconstructiondata and to further expandthe volumeof scientificinformation that ctrrrentlyexists for the RoundValley herd. Moreover,this informationcan be usedto dwelop andrefine the data samplingtechniques outlind in the DHMP that will be usedto evaluatethe efuiveness of project mitigationmeasures on the RoundValley deerherd.

Deqsey CocrucUon Corporation Chapter l. Introductim and tvletbods SoourreelcSki AreI Decr Studv l-l lviuch 1995 PERMIT AREA

Theproposed Snowcreek Ski Area hereafterdesignated the permitare4 is situatedwithin the TML in Sections2.3,9-15.23, and24 of T. 4 S.,R. 27 E' in the MammothRanger District, Inyo National Forest. California (Figure l-l). It comprises approximately3,100 acres of steep,generally nonh-facing, mountainous terrain at elevationsrangng from 7,960to I1.730 feet. The siteis borderedon the southwestby the Sherwincrest, which includes Pyramid Pealc, Red Pealq and Fingers Peak; on the east by the SherwinCreek drainage; and on the nofth by the U.S.Forest Service Mammoth meadowsand the DempseyConstruction Corporation's Snowcreek development (SSA- MasterDevelopment Plan(SSAMDP, pages2-l to 24'1.

Vegetationwithin theproposed permit area is comprisedof eightmajor plant communitiesincluding: barren or fellfield,whitebark pine, mixed conifer, mixed brusiu quakingasperL riparian. wetland, possible wetland, and late-seral mixed conifer (old growth). A completedescription of theseplant communities and their locationswithin the projectarea was provided in theFEIS (page III l7-20) andthe SSA-MDP(Page 2-15).

METHODS

Sestion2.0 of the Draft DeerHerd MonitoringPlan (Raedeke Associates 1994) describedspecific tasks that would be usedto achievethe objectivesoutlined above. Thesetasks are to be conductedin differentstages, related to developmentof the SSA. Thefollowing sections describe the methodologiesused to completespecific tasks performedduring 1994spring and fall preconstructionsurveys.

Radio-telemetryStudies

Radio-trackingof Deer

Groundbased radio-tracking of radio-collareddeer was accomplishedby a non- triangulationmethod or "homing-in"on the animal(Raedeke Associates 1994). Initial relocationswere madefrom a vehicleequipped with a TelonicsoTR-2 receiverand an attachedprogram/scanner (TS-l) anda truck-mounted,omni-directional antenna. A hand-helddirectional antenna was then usedto determinethe generaldirection of the collareddeer. The preciselocation ofthe deerwas determinedby using a spottingscope from a vehicleor movingtoward the signaluntil the deerwas visuallylocated.

Deerwere located two-three timeVweek during daylight hours. Activity, c{r,;.fer t)?e, aspect,elevation, and association with other animalswas recordedfor eachradio- location. All deerrelocations were plotted in the field on U.S. GeologicalSurvey 7.5 minutetopographic maps and the UniversalTransverse Mecator GfnvD coordinatesfor the positionswere recordedto the nearest100 meters.

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-I FtGlrRE:l.l rrFr I - If a deer'slocation could not be verifiedvisually with a reasonableamount of effort andwithout potentialfor disturbanceof the deer,its locationwas determined by triangulationusing a hand-held2-element antenna and a compass.To reducethe sizeof the errorpolygon, triangulation was accomplished by 2 observersobtaining simultaneous bearingsor I observerobtaining > 3 bearingsfrom asclose to the animalas practical. We assessedtelemetry accuracy by comparingknown transmitter locations (transmitters placedby anotherobserver) with thosedetermined by triangulation.

We usedthe programCALHOME (Kie et al. 1994)to estimatehome-range sizes of radio-collareddeer. ProgramCALHOME performsutilizatioru distribution, or home- rangeestimates based on datasets consisting of X andY coordinatesfor successive locationsof a singleanimal. CALHOME provideshome range estimates using several differentmethods. For cbmparativepurpose, we selectedthe minimumconvex polygon (MCP) (Mohr 1947)and the adaptivekernel (ADK) (Worton 1989)methods. Because of smallsample sizes we pooleddata for all indMdualsto reducethe samplesize bias associatedwith thesemethods and to delineatea compositehome range (Andelt and Andelt 1981,Jenkins and Starkey1984). Areasof concentrateddeer use within compositehome ranges were defined as coreareas (Samuel et al. 1985). Coreareas were identifiedas the largestareas within the compositehome range where observed use (based on ADK values)exceeded a uniformdistribution (Samuel and Green 1988).

lvlajor migration routesbetween winter and summerranges were ascertainedby trackingradioed deer closely once they departedthe winterrange. Thelocations of these routeswere mapped on U.S.Geological Survey 7.5 minutemaps and the proportionsof radio-collareddeer using each route was recorded. If a deer'smigration route could not be ascertainedfrom radio-telemetry,then the summerrange location of the animaland datafrom Kucera(1988) wasused to determineits migrationroute.

The summerrange locations of radio-collareddeer were determinedby CDFG from a fixed-wingaircraft during monthly flights conducted from June-September.The locationsof zummerdeer use in the projectarea was determined during field work conductedfrom June l5 to June30.

Holding Area Studies

DeerCount Surveys

Deerwere countedonce weekly from a slow movingvehicle along a fixed route locatedon dirt roadswithin the SHA (Figure1-2). Observationswere made from both sidesof the vehicle,usually by 2 observersusi;,g l0 x 50 binoculars.All countsbegan as soonas light was sufficientto discerndeer; this rangedfrom 0530 in April to 0510in June. Distanceto observedgroups of deerrangd from approximately25 to 2,000m. Data recordedincluded group size,group compositioq numberof markeddeer, vegetationtypg slope, aspest,activity, andtime. In additioq the location of eachgroup

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-I FIG1JR€Il-2 I wasplotted on a 7.5 minutetopographic map of the area. Thepresence of man-made physicalfeatures (e.g., roads, fenceiines. borrow pits) andnatural landscape markers (e.g., rock piles.tree stands. abrupt changes in topography)were used as reference points when plottingdeer locations.

We estimatedpopulation size (l.I) for eachdeer count survey using Chapman's ( I 95I ) estimator,where radio-collared deer were used as the sampleof markeddeer. Criticalassumptions of this mark-resightingmethod were: l) markedanimals were randomlydistributed throughout the population;2) the probabilityof sightingmarked and unmarkedanimals was the same;3) catchabilitywas the samein markedand unmarked animals;4) eachanimal had an identical,but independentprobability of beingresighted; 5) the numberof markedanimals in the populationwas known and therefore, all markersthat werelost wereaccounted; and 6) therewas no immigration,emigration" recruitment or mortality(Davis and Winstead 1980).

RaedekeAssociates ( 1994) suggested that mark-resightingcould potentially be a reliablemethod of estimatingdeer population size on the SFIA. Theretbre,radio-collared deerfrom this andfuture studiesobserved during weekly dawn deer counts will be usedto developa "sightabilityindex" during Phases I andtr of the DHMP. The "sightability index"will be usedin PhaseIII of the DHMP to estimatethe numberof deeractually on the holdingarea based on the numberof deerobserved during a givencensus.

Habitat UseStudics

We analyzedhabitat use in relationto its availabilityusing simultaneous interval estimates(Neu et al. 1974). Chi-squaretests of independencewere used to test hlpothesesthat habitatsused by deerclusters observed during weekly counts were similar amongyears. Chi-square goodness-of-fit tests were used to testhypotheses that habitat usein the holdingarea was proportional to availabilityof the habitatclasses. If the null hypothesiswas rejected (P < 0.05),we calculatedconfidence intervals using the BonferroniZ-statistic (Neu et al. 1974,Marcum and Loftsgaarden 1980, Byers et al. 1984)to testwhich habitatclasses were usedmore or lessthan expected.

Chi-squareGoodness-of-fit tests were used to testhlpotheses that habitatuse by radio-collareddeer in the SFIAwas similarto expecteduse. Boniferroniconfidence intervalswere used to determinewhich habitatsin the SFIAdeviated from expecteduse. We setthe levelof statisticalsienificance at a = 0.05.

Deopccy ConsctuctimCorpordm Chapter l. Introductim ed Metbods Srcwcek SkiAteE Deer Stdv l6 ltuch 1995 Migration Corridor Counts

Infrared SensorEquipment

Trailmaster1500 units (Goodson and Assoc., Lenex4 KS) wereused to determine theamount, timing andspecific locations of deermigration through Solitude Canyon. The Trailmaster1500 operates with an invisibleinfrared light b.ar that automaticallyrecords an eventeach time the infraredbeam is broken. Eachevent is storedby dateand by time (to-the-minute)and g*-b. instantlyrecalled. By positioningthe beamat a certainireight andsetting the lengthof timethat the beamof light is brokeruthe Trailmastercan be used to monitorthe actMtiesof,deer, as opposed to otherwildlife species.

Ten Trailmastercounting stations were established at SolitudePass during the 1994surveys. Each station -spring consistedof two units,a transmitterand a receiver, both of which werefastened to 2 x4 inch posts. Theunits were spaced approximately 60 feetapart, with the infraredbeam aligne d at 24 inchesabove gtound. rne io stations wereoriented back-to-back in a continuousstraight line that spannedthe entirewidth of SolitudePass.

The Trailmasterunits at eachstation were calibrated from directobservations of deercrossing through the infraredbeam and by a comparisonof eventdata with radio- telemetrydata. Thesetwo techniquescan be usedto determinea correctionfactor for eachstatiorL to accountfor individualdeer that arenot countedas some deer pass the countingstations in groups,or for deerthat go aroundthe countingstations.

Habitat Mapping

Habitatsoccurring within the SHA wereclassified according to the Wildlife HabitatRelationships (WHR) System(Mayer and Laudenslayer t988). Color aerial photographs(l:24,000 scale) provided by theU.S. Forest Service, Mammoth Ranger District,were used to makedeterminations on appropriatehabitat classification. Habitats werethen delineated on a 7.5 minuteseries topographic map and their boundariesverified in the field.

Weather Data

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ORGANIZATION OF THIS REPORT

Thisreport contains the followingchapters: o Chapterl, "Introductionand Methods" o Chapter2, "Spring Migration" describesthe resultsof spring 1994deer migration surveys. r Chapter3, "Fall Migration " describesthe rezultsof fall 1994deer migration surveys. o Chapter4, "Conclusionsand Recommendations," provides conclusions to rezults, identifiesproblems and concerns, and lists a numberof recommendationsnecessary to improvespecific tasks identified in the Deer Herd Monitoring Plan. o Chapter5, 'oAcknowledgments,"identifies people who contributedto thereport. o Chapter6. "Citations".

DeryssyCdrstruction Ccpcom Choter l. Intsodtcti@ ud lttlethods SooucrcckSki A€a DEGrSbdv l{ I\,fuib 1995 Chapter2. Spring Migration

Studiesto determinethe temporalpattern of springmigration patternsof deer distributionand habitat use on the Sherwinholding area and on the proposedSnowcreek Ski fuea andthe locationsof migrationroutes used by radio-collareddeer were conductedbetween April 1 andJune 30, 1994.

Thetemporal pattern of the 1994spring migration consisted of threedistinct stages: l. StageI wasthe northwardmovement of deerbetween the winter rangein Round Valley andthe SHA.

StageII wasthe holdingor delayperiod of springmigration. This periodof migration comprisedapproximately l0 weekswhen deer from the RoundValley herd delayed migrationon the SIIA.

J. StageIII wasthe movementof deerbetween the SHA andsummer ranges located on the eastand west slopesof the SierraNevada.

StegeI: Migration Betweenthe Winter Rengein Round Valley and the Sherwin Holding Area

Duringspring 1994,the migrationroutes used by 66 of 77 radio-collareddeer weredetermined. Of these66 deer,63 migratednorth from the RoundValley winter range,2 migratedsouth, and I remainedin RoundValley (CDFD, Unpubl.data). The migrationsroutes used by the remainingi I decrwere undetermined.

Locationsof DeerMovements

Migration from the R\ MRbegan in early April; the first radio-collareddeer was detectedmoving north of RoundValley on April l. Themigration route used by deer migratingnorth from Round Valley followed the baseofthe easternescarpment of the SierraNevada at elevationsranging from approximately2,300 to 2,500m (Figure2-l). Upon leavingthe winter range,deer first passedthrough the vicinity of SwallMeadows, a communitycomprised of a numberof rural subdivisionssinrated directly abovethe winter rangenear the baseof the Sierraescarpment (Figure 2-l). Taylor (1993a)reported that the majorityof deermigrated along a rathercircuitous route that passedto the westof the lirryon Ranchand the Hilltop Estatess.lbdivisions.

After migratingpast the Swall Meadowsarea, deer continued northwest through WhitcherMeadow and SandCanyon, and then crossedWhiskey Canyon (Figure 2-l).

@sery Constructior Corpcation Chsptcr 2. SpnngMigaron SnowcreckSki&ea Deer Shdv 2-l lrgch 1995 Oncepast Whiskey Canyon, deer continueci west. crossed the mouthof Rock Creek Canyon,and then passed directly above the communitiesof AspenSprings and Crowley Lake. Fieidreconnaissance surveys revealed the presenceof numerouswell-established deertrails located within approximately 200 merers (m) southof thesenno subdivisions (Figure2-l).

After movingpast the communit-vof CrowleyLake. radio-collared deer delayed migrationfor l-2 dayson a seriesof lateraimoraines iocated adjacent to Hilton and McGeeCreeks (Figure 2-l). Thesemoraines were dominated by big sagebrushscrub vegetationand provided deer with snowfree southerly aspects where they hadaccess to succulentspring forage.

Themigration route used by deernorth of McGeeCreek contoured the baseof McGeeMountain at elevationsranging from 2.200-2,400nL andthen crossed through the TobaccoFlat area. North of TobaccoFlat, deer crossed the ConvictCreek drainage betweenConvict Lake and Highway 395. andthen entered into the Convict Knolls.

StageII: The SherwinHolding Area

ConvictCreek has traditionally been recognized as rhe eastern boundary of the SIIA (Kucera1985, USFS 1991,DCC 1993).However, radio-telemetry data from spring andfall 1994determined that deerdelayed migration on the lateralmoraines located betweenConvict Creek and Tobacco Flat. Additionally,deer delayed migration north of Highway395 in thevicinity of the Mammoth-JuneLakes Airport. Basedon this knowledge,deer migrating south of Highwav395 were considered to havearrived on the SHA oncethey crossed Tobacco Flat (Figure 2-l). Deermigrating north of Highway395 wereconsidered to havearrived on the holdingarea once they entered the vicinity of Doe Ridgeand the Mammoth-JuneLakes Airpon.

Timing and Intensityof Deer Useon the SherwinHolding Area

Thetemporal pattern of deermigration on the SHA duringthe 1994spring migrationwas determinedfrom ground basedradio-tracking of telemetereddeer and deer count surveyscondusted in the SHA.

Rrdio-collareddeer. Of the 63 radio-collareddeer that migratednorth from the RoundVdley winter rangeduring the 1994spring migration, 5l delayedmigration on the SI#g 3 delayedon the CasaDiablo deer herdholding are4 locatedsome 9 airline km north of the projectarea near the headwatersof the OwensRiver; 6 delayedmigration in the vicinity of McGeeMountain, located approximately 3 km southof the Convict Lake Road; and3 deerdelayed migration in the vicinity of CrowleyLalce.

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I | - Percentof DeerAniving on SHA(n = 53) -'- Percentof DeerDeparting From SHA 1n = c3) | I -", I i Flgurez-2. Cumutativepercent of r-roroou"in"Jn-Colf"r"JO"er nrriving onanO o"parting t:' L_--- I19tr*qlgldinqlp{ut!'s !9 1991!q'!ng y!g9!ion. I Deerdelayed migration on the SSAfor a periodof approximatelyl0 weeks,from Aprii l3- June21. Of the 51 deerthat delayed migrarion on rheSSA approximateiv257o wereon the holdingarea on April 17,and nearly 50o/o on April 24. By May l, approximately75o/o of deerhad anived on rhe SHd the lastdeer arrived on Junel2 (Figure2-2).

Peaknumbers of radio-collareddeer were observedon the SHA duringthe second andthird weeksof May, thendecreased during late May throughmid-June as deer migratedto the surlmer range(Figure 2-2). Approximately25o/o of radro-collareddeer left the sHA betweenMay i9 and26,14o.6 between May 27 andJune 4, andL3Yo betweenJune 5 andJune 9. Deerdelayed migration on the SHA for an averageof 31 days (range: 3-60days) (Figure 2-3).

Of the 5l radio-collareddeer detested on the SHA duringspring migration, a totd of 25 (49o/o)are known to havedelayed migration within the boundariesof the proposed SSAperimit area. Of these25 deer"approximatelrl20Yo had arrived in the permitarea by Aprii 2l and50Yo by May 5 (Figure2-a). By May 23,approximateiv 85% of radioeddeer hadarrived in the permit area;the lastdeer arrived on June12.

Peaknumbers of radio-collareddeer were locatedin the permitarea during mid- May. Approximately25Yo of deerdeparted from the SSApermit area between 12 and24 Mzy, 5Q%obetween 24 and,26 Mray. By 2 June' 75o/o of raAioeddeer had migrated from the projectare4, the last deermigrated on24 June. Deerdelayed migration in the SSA perrnitarea for an averageof 18days (range 245 days)(Figure 2-3).

Ofthe 63 radio-collareddeer that migratednorth from the RoundValley winter range,one died on the SHA duringthe springholding period, and a seconddied shonly afterit left the SHA (CDFG,Unpubl. data). A third radio-collareddeer died on the Casa Diablodeer herd holding area (CDFG. Unpubl. data). Thus,ro our knowledgeoniy 3 of 63 deerthat migratednonh from the RoundValley winter range died during the 1994 springmigration period.

Deer Count Surueys. Deercount surveys provided a secondindex ofthe temporalpattern of springmigration on the SHA. A total of l0 deercount surveys were conductedin the SHA betweenApril 7 andJune 9,1994. Deercount surveys indicate that deerbegan arriving on the holdingarea during the third weekof Aprif 37 deerwere countd nearthe baseof LaurelMountain during a surveyon April 13 (Figure 2-5). A sharpincrease in deer numberson the holdingarea occurred during the fourth weekof Apnl, andpeak deer numbers were countd on May 12(Figure 2-5). After May 12,deer numberson the holding areasteadily declined as animalsmigrated to the sunmerr:rng€.

The temporal Patternof deermigration from the winter rangeand zubsequent anival on the holding a^reawas approximatetythree weeksearlier than spring 1993(Taylor

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0 J.::,..l-----L-- l.-,- | L- | r- l---.1_-. t--.__L_._1,___L__l__ l___---L_-._l __.L __l 4t15 41214122 4127 4lN sls 5t10 5t12 5t16 st?0 5t21 51225t23 5t24 5t25 128 5/30 6n1 6n2 6/03 6/04 6/06 6/10 6t12 6t24 'tfi

- Percenlof Deerturiving on SSA(n = 23) '-...Percenl of DeerDeparting From SSA (n = 20)

Figure2-,f. Gumulative Percent of HoldoverRadio-Collared Deer Arriving on and Departlngfrom the SnowcreekSki Areaduring the 1994Spring Migration. 280 qt0) o 240 o o € 2oo E z5 G 160 o 120 ffiF Ffl BO ffi il t.l 40 . 0 flt ffi l_ffi 6125 v25 5t5t26, 6t2 6/4 d6-l$1, 6,9 6117 4n'-ffi-m--- 4/13 4t21 4t23 4t28 4/30 s/5

| ;se'idtrri * seri"si-il]

Figure2-5. Total Numberof DeerGounted per Day duringDeer Count Surveys Conductedin the SherwlnHolding Arsa, Spring 1993 and 19e4 1993)(Figure 2-5). In spnngi993. deer were first observedon thehoiding area on April 30 andpeak numbers were counted on Mav 2 (Figure2-5).

The variationbetween the 2 yearsin the temporalpattern of spnngmigration was relatedto winter severiwand spring temperatures. The i993 springmigration followed a severewinter, with total snowfallaccumulations in MammothLakes exceeding l20o/o of normal. This heavysnow pack persisted until late-Aprilalong migradon routes and on the sunmerrange because cool springtemperanrres of l9o Fatrenheit(F) in Marchand 2lo F in Aprii pre\tentd snowfrom meltingrapidly. As a result,plant phenoiory at thesehigher elevationswas delayed,forcing deer to remainon winter andspring ranges where herbaceousspring forage was readily available.

In comparison,the 1994spring migration enzued an extremelymiid winter,with total snoufallaccumulations in the easternSierra averagrng approximate\ 50Vo of normal. Consequently,snow melt and vegetation gowth alongmigration routes and on the holdingarea occured earlier.motivating deer to begrntheir migrationfrom the winter rangeduring the secondweek of April.

Severalauthors (Russel 1932, Leopold et al. 1951,Loft et al. 1989)have associatedthe timing of springmigration from the winter rangewith the recedingsnow packand the availabilitvof springforage. Bertram and Remple (1977) found that deer from the North Kings herdmigrated from the winter rangeapproximately two weeks earlierfollowing dry wintersof normalto belownormal precipitation. In Colorado, Garott et al. (1987)reported that the timing of springmigration following a severewinter was approximatelyI monthlater than after winters that were relativelymild. These authorsh1'pothesized that to initiatemigratiorl which requiresadditional energy demands, deermust first reversethe negativeenergy balance experienced during the winter. Hence, aftermore severe winters, deer migration is delayedon lower elevationwinter ranges to extendthe intakeof high qualiwforage and improve the deer'soverail physiological condition. Garrottet al. (1987)also suggesred that by delayingmigration after a severe winter,deer can avoid the heaviersnowpack at upper elevations,which would impede their movementsand reduceforage availability at a time when energydemands of pregnantdoes are high becauseofthe latestage ofpregnancy. Energy reserves are depletedwhen deer are forced to traversein snow(Wallmo and Gill l97l), andthe energy output requiredby deerto feedin snow often exceedsthat suppliedby the food eaten (Kelsall1969).

Kucera(1988) used deer count survsys in conjunctionwith radio-telemetryto determinethe ternporalpattern of deermigration from the Round Valley winter range. In this prwious worlg conductedfrom 1984-1987,deer left the winterrange in earlyApril andwere presert "in the hundreds"on the holding areaby the time of the first deercount surveyin mid-April. Maximumnumbers of deer on the holding areawere countedin late April and early May, with numbersdeclining to a minimumin mid-June,as deermigrated to the srunmerrange. This panernwas consistent:rmong years despite extremes in the severiwof winter.

D'lrtttssy Csnsustion Ccporanm Cbapt€r2. SpringMientim SnourcrcckSki ArEa DeE Studv 2-9 lvtuch 1995 Kucera( 1988)hypothesized that srmilaritiesamong years in the temporalpattern of migrationfrom the winter rangemav have been reiated to nutritionaifactors, assuming thatforage on the winter rangein early-Aprilwas of poor qualitv.or in lesserabundance thanon the holdingarea. Deermay have aiso been anempting to seekthermai relief at upperelevations because murimum davtime remperatures in Bishopaveraged about 7T in April and80e in May.

Estimatesof Deer Abundanceon the SherwinHolding Area

The probability of sightinga deer,as estimated by the probabilityof sightinga markeddeer (Bear et al. 1989),averaged 50% during the lasttwo weeksof April, 35% duringthe first two weeksof May, and2Qo/oduring the last week of May andthe first two weeksof June(Table 2-1). Thistrend indicated a patternof increasingvisibility with increasingdeer density and group size.and decreasing vegetative cover. A simplelinear regressionyielded a significant(P = 0.064)and positive correlation between sighting probabilityand numerical group size (Figure 2-6a). Sightingprobability increased as group sizeincreased. Sightiabilitywas highestin late April when averagegroup size was highest.Others, Cook andMartin (1974),Samuel and Pollack (l9El), andSamuel et al. (1987),have demonstrated the importanceof group sizeas a factoraffecting sightability in ungulatepopulations. There was also a positiverelationship (R'z= 0.53) between sighting probabilityand deer density (Figure 2-6b), which according to Samuelet ai. (1987)may partiallybe relatedto the influenceof group size.

Vegetationcover is believedto be an importantfactor influencingsightability (Samuelet d. 1987,Ackerman 1988). Althoughwe did not estimatepercent cover for thevarious vegetation types in the holdingarea, our studyalso suggested that vegetative covermay substantiailyinfluence deer visibility. Sightabilitvwas highestduring surveys conductedfrom mid-April throughmid-MarciU when 79Yoof deerwere observed in open sagebrushhabitat. However,sightability decreased in lateMay andearly June as the propoftionof deerobserved in otherhabitat types providing greater cover, increased (Figure2-7).

We did not attempt to fully determinethe magninrdeof visibility bias(Samuel et al. 1987)associated with our roadsidesurveys. Numerous factors includinganimai behavior anddispersiorq topography, obsewer experience, weather, equipmant, and methods may affectthe numberof animalsobserved (Samuel et al. 1987,Davis 1990).

Mark-resightingestimates for deercount survcysconducted on the holdingarea duringthe 1994spring migrationranged from a low of 37 deer(95% Cl = 3242) on April I 3 to a highof 809 dw (95o/oCI = 5I 5-1,103) on May I 2 (Table2-l ). Bleich(pers. comm.)reported a 1994winter populationestimate for the Round Vdley herdof 1,127 derr (95%oCl= 929-1,325),and telemetry information indicated that approximately650/o of radio-collareddeer delayedmigration on the SIIA during the 1994spring migration. Thereforgutitizing thesetwo factorsand assuming that deerwere trappedin proportion

DeryscyCoustrurtim Corpcanm Cbatrcr2.SpingMigrano SoousockS&i &cr DccrSlttrdv z-to l{sch 1995 Table 2-1. rVeanpopulauon esunarcsand ranges'wrrhin957o confrdence limits for mule deercounted on the Shenvinholdins area during l0 deercounr survevs condrcted from April 7-June9. 1994 Numberof Estimarcd Nurnberof Radio€d Number of Number of Radioed Deeron the Deer on the 95yo Darcof Deer Deer Holding Holding Confidenc€ Probabiliqv Survw Observed Obsen'ed Afea fuea Intervais Sighting Apni 7 I 0 0 April 13 37 I I 37 3242 t00 Apnl 2l 236 7 l4 443 247439 50 Apnl 28 231 t2 24 445 362-524 50 lv{av5 2{8 l0 32 552 410-l104 3l M4v 12 315 l5 38 809 515-l103 39 N,Iayl9 250 6 40 tvlav26 r37 ) 30 7t2 272-lrs2 17 June4 E2 6 26 319 137-501 23 June9 6l .t 20 259 E5433 20 u Poprlation e$rrnateswerc not ma& for thesesunevs

DeryscryConstrucnon Corporaum Chadcr2. Spnng Migratm Snoc,EGEkSki&€a DecrShdv 2-tr lrrch 1995 U.J Y=0.021+0.0331x lR. = 0.61.9 tP = 0.0356 (! 0.4 oe o) 0.3 ctr U)

v.z

0.1

910 AverageGroup Size

0.6 j I I I i 0.s t- tY:0.13 + 0.001x Rr = 52.8 .= P = 0.0643 0.4 €G - (L ot 0.3 t- ot o

I l 200 Numberof Deer

-' Fisure2s. Therr$!_q SighfmgpreUgOlity Numberoroeer*c^ouiteo"inthe'_Eierilii'niiiingArea(2{b) du$g the 1994 Spdng Uigratio; 100 llillffililtililitl s0

80

70

E60 o :so c o o b40 (L

30

20

10

0 4n ilB 4t21 4t28 5/5 5t12 5/19 5t26 6t4 6/9 SurveyDate

I r Sagebrush @ JeffreyPine = MonlaneChaparral I Wet Meadow [In PerenialGrassland I

Fl9ure2-7. Percentof DeerObserved by Ve_getatiq Typg on the Sherwin Holding Area during the I I 1ee4Spring Migratlon L I to their aveilebility,an estimated730 deer delayed migration on the SHA. Thus,our highestpopulation estimate of 809 deer(9So/oCI = 515-1,103)appears reasonable based on the mostrecent CDFG winter population estimate.

Patternsof Ileer Habitat Useon the Sherwin Holding Area

Dccr Count Surveys. A Chi-squaretest of independenceshowed no significant differencebetween spring 1993 and spring 1994 in the occurrenceof deergroups within anyhabitat tlpe (X,t: 3.84,4 d.f.,P > 0.05). A total of 160deer groups were observed on the SHA duing l0 deercount surveysconducted from April 7 to June9, 1994(Table 2-24Figure2-8). Ofthese 160groups, approximately 55o/o and26Vo were observed in sagebrushand montane chaparral habitats, respectively (Table 2-2d| Ten percentof all deergroups were observedin perennialgrassland habitat on the Lar.rel Mountainburn, l2Yo nJeffre;'ypine forest, and4o/o in wet meadow. Chi-squareGoodness-of-fit comparisonsshowed that the expectednumber of deer groupsin eachhabitat differed significantlywith the occurrenceof habitatcategories in the holdingarea(a2: 54-76;4 d.f,, P < 0.05). Montanechaparral was used and other habitats were avoided or usedin proportionto availability.

In comparisorLa total of 152deer groups wer€ obseryedon the SIIA during 10 deercount suwcys conducted befween April 23 andJune 25,1993 (Table 2-Zb,Figute2- 9). Ofthese 152groups, approximately 53Yo and26o/owere observed in sagebrushand montanechaparral habitats, iespwtively. Approximatelyloo/o of all deer groupsoccurred in perennialgrassland habitat on the LauretMountain burn and l07o were observedin Jeftey pine forest (Table 2-2b\. Only l% of deer groupsoccurred in wet meadow. Chi- squaf,eGoodness-of-fit comparisons showed that the expectednumber of deergroups in eachhabitat differed significantlywith the occurence of habitatcategories in the holding area(12 = 53.3i4 d.f., P < 0.05). Deerused montane chaparral significantly more than expected.while sagebrushand wet meadowhabitats were used significantly less (Table 2- 2b). Perennialgrassland and Jeftey pinewere used in proportionto their availability.

Habitatuse differed significantty during June in 1993(72: 58.48;4 d.f., P < 0.05)' andMay (Xz: 25.94,4 d.f.,P < 0.05)and June (I2 : 93.384 d.f.,P < 0.05)in 1994 (Figure2-10). During May andJune, montane chaparral was usedand sagebrushwas avoided.

Mule deerin the ea*ern Sie'rraNwada generallyforage on grassesand forbs in the springand browse in the summerand fall (Taylor 1991,Kucera 1988). Ilabitat use appearedto be closelyrelated to the temporalavailability and phenologicaldwelopmant of herbaceousspring for4ge. In both y€q deerused montane cbaparral habitat in greater prroportiorsthan ocpect.O. fUt habitattype is a dense,multilrryered scnrb comprised of a ,narirtyof plant speciesthat provideda diverse,bigh quality dia for deer. A high quatity die resultingfrom a diversrtyofforage tlpes is importantto holdoverdeer, especially pragnatrtdoeg becauseit enablesrnimali to selestthe most nutritious foods (Swn 1948)

Derycy Cotr#ustic Corpcatlm CbaSGr2.SPringMigrom Soorscck Ski &a Dccr Sudy 2-t4 Itmh 1995 Table 2'2a. Utilization-avarlabilitv data for dominatehabitat rypesin the Sherwinholding area lvlammoth Lakes.California. Utiliz+ion data is basedon locationsof 160 deer groupsobserved dring l0 deercount survevscon4rcted during spring 1994. Ac[ral Proponion Expected Proponion Total of Total Nunberof Numberof of Groups Bonfenoni Flabitat Estimated Acreage Groupa Groups Oberved Inrcrvals Type (piol Acreage Observed Otberved Pi for Pi JP E00 0.121 9 l9 0.056 0.0475Pr30.1E9 SB 4,500 0.681 88 109 0.550 0.5383Pr30.5611 MC 700 0.106 4l t7 0.256 0.159

'Indicates a difrerencear the 0.05 lwel of signrficance JP= JeffreyPine. SB = Sagebnrsh"MC = MontaneChaparral. WM = Wet Meadow.PG = Perenmal Grassland

Talte Z-ZU.Utilization-availability data for domrnarchabitat typ€sin the Shenrin holding area lvtanmoth Lakes California. Utilization data is basedon locationsof 152 decr groupsobsewed during l0 deqcount survels condrcted drrine sorine 1993. ActEl Proportion E:Aected hoportion Toeil of Total Numberof Numberof of Groupe Bonferronr Habitat Estinated Acreage Groups Groups Oherved Intewals T-vpe Acleaqe @iol Observed Gserved Pi forPi JP E00 0.121 15 l8 0.098 .035

DcryscyCo*uctio Corporaion ChSGr2. SfingMigratio Smrr*S&iA€aDecrStdy 2-t5 [,!rch 1995 u o q @ z o z tr E

I G s q o ts

g :@ z z o F x o G E

J

b F F

,.. 0.7s ; o.f q 0.75 5 o.s I : F L 0.6 F oiii F F F 0.0 l- l- o 0.45 z "i5 tr tlt O U,J E 0.35 ; o.as F F F A oli F F.iiF 802 603 c o.t5F E 0"21 {"m E P ool 3 ';'; o.t go5 8fr g+E0t6 E o.t' I o.l r 06 I OF a ss MC !w Pc HfftltD.

Aooel!6th:rr.h r^.ldAtoF.toolurlo a Eedad Fopdtqr C U.{a

Figure2.10.confidenT.'!nt9ry3|a-(95%)|nt|icatingMu|eDeeru,"ffi Holdins g:.1ljgs-l[1.1g-T,s'pgo Bh;k oot nJeregenrthe proporton orEach Ha b itat Ava la b re. e ri* ;u[rgtign. 6oiJc Jo*lni"*iilft][;#ffi;,,-"il Above Avoidance,and In the Intervaiuseinproportion to Avairabirity. andquickly regain condition lost overthe winter (Short 1981,Garrott et al. 1987). The dense,multilayered structure of montanechaparral vegetation also provided important thermaland hiding cover for deer.

Radio-collaredDeer. Habitatuse on the SHA by radio-collareddeer was determinedfrom 237 visuallocations of collaredanimals. Triangulations were not includedin the habitatanalysis because many of our azimuthreadings were not successfullyconverted into estimated)q Y coordinates.In additio4 for thosereadings that wereconverted, large error polygons(> 0.25ha) madeit difficult for the observerto placethe locationa deerwithin a singlehabitat. In spring1994, radio-collared deer avoided(used less than expected) perennial grassland habitat on the LaurelMountainburn (P < 0.05),while other habitats were used in proportionto their availability(Table 2-3, Figure2-l l).

Table 2-3. Utilizauon-avarlabilitvdata for dominarehabitat [vpesin the SherwrnHolding Area Mamnoth l,akes.California. Utilization datais basedon 237 visual locationsof 27 radio

Patternsof Deer Distribution on the Sherwin Holding Arca

Observationsfrom 27 radio-collareddeer (n =237)were used to estimatea compositehome range delineating the approximatesize and boundaries of SHA. Mnimum convexpolygons, after combiningall sarnpleobservations for the 27 deer, provideda total areaestimate of 6,888 hectares.Outlier observationssignificantly effectedestimates of holding areasize. For example,the removalof 3 outlier observations from the dataset reduced the MCP holdingarea size from 6,888hectares (l0O% MCP) to 5,738hectares (99/o MCP). When95o/o urd 90% of the sarnplepoints were usd estimat$ of MCP declinedto 3,852 and 1,761hectares, respectively (Tabte 24, Appendix Figure l). In comparison,calculated isopleths of the adaptivekernel (ADK) rangd from I1,260to and2,949 hectares for 100% and90o/oof the samplepoints, respectively (Table 2-4, AppendixFigure 2).

DeryseyCon*nrtim Corpcanm Ch4ter 2. Spring Migatim SnmrcreckSki Ar€sDq Studv 2-t9 lriucb 1995 Table 2-1. Calculatedmule deerhome range areasthectares) for the Sherwrnholding areaand the SnowcreekSki Area using the minimum convexpolygon and adaotivekernel methods ADK' Relocauons (n) 100% Wo/o 10ff/o 9f/o ShenvinHolding Area 6Er8 5738 3852 r76t 11260 9939 5720 2949 'Minimum ConwxPolygon(Mohr 1947) 'zAdaptle Kernel (Worton 1989)

A potentialfault of MCP andADK is that bothassume that the total areawithin rangeboundaries are usedby an animal. Our dataappeared to fit this assumptionfairly well with the 90% MCP (AppendixFigure 2). With the exceptionof the Jeftey pine forest,which occupies the centralportion of the holdingare4 we foundno largeunused areaswithin the SHA andthere were few outlier locations. However,many deer moved throughthe Jeffreypine forest to accessmigration routes located west of the holdingarea.

Largeisopleths of theADK (using>9tr/oof locations)included areas that almost certainlywere not usedby deer,such as the TML (AppendixFigure l), suggestingthat ADK wasnot appropriatefor estimatingtotal rangeare4 althoughthe 85% ADK isoplethswere useful for identifyingcore areas within the SHA.

The 90o/oMCP of 1,761hestares was used to derivean estimateof deerdensity on the holdingarea during spring1994. Basedon deercount survey dat4 peakdeer numbers on the SHA duringspring 1994 were estimated at 809 deer(95o/o CI = 515-1,103).This estimaterepresents a densityof I deer/0.46hectares or 2.17deer/trectare.

Isoplethsof the ADK using85% of locationsidentified rwo majorcore areas within the SHA (AppendixFigure 3). Corearea A is locatedin the lower easternportion of the SHA extendingfrom approximatelyMammoth Creek south to the top of the Laurel Mountainburn (2,400 meters elevation), and from LaurelCreek east to the Cold Springs campgroundarea (Appendix Figure 3). Corearea B includedthe lower northernportion of the SSA from approximatelyMammoth Creek southto the Mammothmoto-cross, and from MammothRock eastto the Sherwincampground area.

AppendixFigure 3 maygive deceptiveresults regarding the numberof animals usingeach core area. Therefore,it is importantto understandthat core areaswere delineatedfor the purposeof identi$ing high useareas within the SIIA andare not a reflectionof populationsize. The isoplethof core areaA was basedon approximately109 locationsof 25 radio-collareddeer (x : 4.4 locationddeer),while the core areaB isopleth wasderived from approximately92 locationsof l5 radio-collareddeer (x = 6.1 locationVdeer).The fact thatthe isoplethof onecore area includes more data points than that of the other is strictly a function of samplesize.

Deqscy Codnlctim Corpcom Cbapt€r2. SpringMgratm SuoqrrcrekSki Ar€a DccESUdv 2-21 I\,tmb 1995 StegeIII: Decr Migration betweenthe Sherwin Holding Area and the SummerRange

The locationsof deermigration corridors and the percentageofthe RoundValley winter deerpopulation that usedthese corridors was determinedfrom aeriaiand ground- basedradio-tracking of collareddeer.

Migration RoutesOver the Sierra Crest

Basedon the movementsof radio-collareddeer, Kucera (1988) delineated the migrationroutes over the Sierracrest used by deerfrom the RoundValley population. Usinga sampleof 27 radio-collareddeer, Kucera (1988) calculated the percentof the total herdthat usedthese migration routes (Table 2-5). In the DHMP (RaedekeAssociates 1994),the deerthat migratethrough these different geographicalareas are referredto as "herd segments".The followingrepresents the proportionof the RoundValley population representingeach herd segment (Kucera 1988):

. Thirty-four percentof deermigrated south from the Round Valley winter rangeand usedthe BishopPass, Lamark Pass, and Piute Pass migration routes.

o Sixty-sevenpercent of deermigrated north from the Round Valley winter rangeand usedthe HopkinsPass, Solitude/Duck Pass, Mammoth Pass, and San Joaquin Ridge migrationroutes. The following includesa brief descriptionof theseherd segments:

o The Hopkinspass herd segmeft diverts from the mainmigration corridor beforereaching the SHA migrateswesterly up the McGeeCreek drainage and crossesthe Sierracrest over Hopkins Pass.

o The SolitudeiDuckpass herd segment delays spring migration on the SHA and then migratessouth to the sunmer rangeover two passes:Solitude Pass, locatedin the permit areaatop the SherwinRange, and Duck Pass,located some5 km farthersouth on the SierraCrest.

o The MammothPass herd segmentdelays spring migration primarily in the westernportion of the SHA whichincludes the permitarea. Theroute used by this herd segmentheads westerly through the permit areabelow Mammoth Roch pa$es throughtlre ManrmothLakes Basrq andthen crossesover lvlammothPass into the Middle Fork of the SanJoaquin River drainage.

o The SanJoaquin herd segment migrates northwesterly from the SIIA and crossesthe Sierracrest over SanJoaquin Ridge, between Minaret Summitand DeadmanPass.

DeryecyCoastructim Corporarron Chpt€r2. SpingMig1son SnoutrrcckSkiArea Deer Shrdv 2-22 lvtsch 1995 Table2-5. Percentof radio-collareddeer that useddifferent migration routes over the Sierracrgst. based on radiotelemetrv data from Kucera(1988) and spring 1994. Percentof RadioedSample Kucera1988 (n = 27) Spring1994 (n = 39) MisrationRoutes Number Number Percent SouthernRoutes BishopPass I 4 LamarkPass I 4 PiutePass 26 I J z ; 9 34 I J NorthernRoutes HopkinsPass 4 l5 3 8 SolitudeiDuckPass 7 26 l5 38 MammothRock 2 7 l3 JJ SanJoaquin Ridge T l9 7 l8 27 67 39 97

Migration RoutesOver the SierraCrest - Spring 1994

Ofthe 66 deerfor whichmigration routes were determined during the 1994spring migration,a total of 39 crossedover the Sierracrest to west sidesunrmer ranges. Of these39 deer,28 migratedthrough the SSApermit uea;7 crossedover SanJoaquin Ridge;3 migratedover HopkinsPass; and one crossed over Piute Pass (Table 2-5).

Migration through the SSA Permit Area. Twenty-eightof the 39 deerthat migratedover the Sierracrest moved through the SSApermit area. Of these28 deer,13 usedthe MammothRock migrationroute to accesssummer range located in the MammothLakes Basin and the Middle Fork of the SanJoaquin River drainage. All l3 of thesedeer delayed migration for I or moredays in the SSApermit area (Figure 2-3). Fifteenof the 28 deerthat migratedthrough the SSApermit area moved through Solitude Canyor;and then over SolitudePass and Duck Pass,to surnmerrange located in the SouthFork of the SanJoaquin River, Fish Creek, and Mono Creekdrainage's. Ofthese l5 deer,6 delayedmigration for I or moredays in the SSApermit area (Figure 2-3).

Migration Over San Joaquin Ridge, Hopkins Passand Piute Pass.A total of 7 deermigrated over SanJoaquin ridge to summerrange located in the upperMddle Fork of the SanJoaquin River drainage(Table 2-5). Ofthese7 deer,2 delayedmigration for I or moredays in the SSA permitarea. Threedeer crossed over HopkinsPass to theirwest sidesummer ranges located in the Mono Creekdrainage, and I deercrossed over Piute Pass(Table 2-5).

SummarTof Deer Migration Over the Siena Crest. Duringspring'1994, a total of 77 radio-collareddeer were alive at the beginningof springmigration. Of these77 deer,3 diedduring the springmigration period. Ofthe remaining74 de\28

DopseryConstnrctim Corpcaron Cb$cr 2. Sprhg lv{ignttm SnocrsGckSki AreaDecr Sttdv 2-23 Itrth 1995 (38%\ migratedthrough the SSApermit are47 (9%) crossedover SanJoaquin Ridge; 3 (4%)migrated over Hopkins Pass; and one (l%) crossedover Piute Pass (Table 2-5). of the 28 deerthat migratedthrough the SSApermit are4 I 3 deer( I 8% of the RoundValley population)used the MammothRock migrationroute and 15 deer(2}Yoof the Round Valleypopulation) used the SolitudelDuckpass migration route. Usingthe CDFG 1994 winterrange popuiation estimate of 1,127O-eer (COfC, Unpubl.),the proportionof the deerherd that migratedthrough the SSApermit area numbered about 430 deeror about 38%of the RoundValley population. This was approximately half the numberof deer estimatedto havedelayed migration on the ShenrinHolding Area durin gthe 1994spring migration.

Basedon the percentagesof the differentdeer herd segments that migrateover the Sierracrest (Kucera 1988), Raedeke Associates (1994) estimated that some440 deer (33%) from the RoundValley population migrated through the SSApermit area in spring 1993. Duringspring 1994,the proportionroldeo using-solitudeand Mammoth passes- 1as approximatelyl4o/o and 26Yo greater. respectively, t-han reported by Kucera( 1988) (Table 2-5). Conversely,the proportionsof d'eerusing the SanJoaquin Ridge and HopkinsPass migration routes were approximately fZ and8%less, respectively, than reportedby Kucera(1988).

It is importantto notethat manyof the lifts andski trails formerlyproposed in the vicinityof the Motocrossand lower SolitudeCanyon have been eliminated. Additiona[y, manyof the facilitiesserving Solitude Canyon and the pfamid peakareas have been reducedor relocated(SSA-MDP, pages 3-3 to 3-4). Thesechanges were incorporated in the MountainMaster Planto substantiallyreduce encroachment into areaswhich are currentlyidentified as deer sensitive.

As statedearlier, if a deer'smigration route over the Sierracrest could not be determineddirectly, the routewas reconstructed using information from otheraspects of the deer'slife history,such as where it delayedmigration and where it summeredon the westslope of the Sierra. However,this approachisproblematic from the standpointthat somedeer could have potentially accessed their summerranges using one of several differentpasses. For this reasorLthe proportionsof deerreiresenting each herd segment are meantonly as approximations.

Timing and Intensity of Migration through the snowcreekSki Area

RcmoteDeer Counters. The Trailmasterunits at Solitudepass record ed344 eventsthat could be usedto determinethe timing andintensity of deermovements through the permitarea. Deer beganmoving througb Solit:d.e Canyon and over Solitudepass on lvtay22, and thesemovements continued until June29 (Figure 2-lZ). peak migration thr_ogshthe SSApermitt area occured betweenJune 2 and 15,whin 62yo of all eventswere recgrded. Approximately l8o/oof events were recorded "ppto*iriltelybetweenMay 22 andJune8, andl9/o of er/elrtsbetween June 16 md29.

Dqtt[rscy Con*ructim Ccpcarion Cbsptcr 2. Sping Mig8tion Snorucck Ski&!! D€ Strdv 2-24 It[ach 1995 22 23 21 25 20 27 28 29 30 3! 10 11 12 13 l,l 15It6 t7 t8 t9 20 21 22 23 21 26 26 27 28 29 JhMay June

Figure2-12. Numberof EventsCounted per Day by the TrailmasterUnits at SolltudePass, SpringMigration 1994 The 1994spring migration followed an extremelymild winter,with total snowfall accumulationin the MammothLakes area averaging approximately 50o/o of normal. Taylor( 1989)reported that deermovements through Solitude Canyon lasted from approximatelyMay 14to June24 followingwinters of belowaverage snourfall (Table 2- 6). In comparison"during the springmigration of 1993,when snoudall accumulations in the MammothLakes area exceeded l20o/o of normal deermovements throush Solitude Canyonwere delayed until May 30.

Verilication of DeerCounting Accuracy. Duringthe 1994spring migration the accuracyof the Trailmasterunits at SolitudePass was determined from direct observationsof deercrossing through the infraredbearq from a 35 mm cameraused in conjunctionwith the Trailmasterunit at station6, andby comparisonof the Trailmaster datawith radio-telemetrydata.

Directobservations of deercrossing over SolitudePass and through the counting stationswere made on May 30. Duringthis day of observation,a total of 4 deerwere observedcrossing over the pass.At 10:34a.m., 3 deer(l adultfemale and2 yearling females)attempted to movethrough station 6, whichwas located on the mainmigration trail crossingover the pass. Station6 wasthe only stationwith a 35 mm camera;the camerawas later stolenin earlyJune. As the first deerpassed through the infraredbeanl the flashfrom the camerastartled the animals,causing the adult doe and one ofthe yearlingsto fleeback to the norththe way they hadcome; I eventwas recorded. At 10:35a.m. the doe andyearling again tried to movethrough station 6, howeverthe flash from the cameraagain startled the animals,causing them to retreatto the north; I event wasrecorded. At 10:36a.m., both deersuccessfully crossed through station 9 locatedat the upper,east end ofthe pass,2 eventswere recorded. The fourth deerobserved, an adultdoe, passed, without hesitatioqthrough station 5 at 12:20p.m. Thus,the 4 deer that crossedover the passon May 30 resultedin 5 eventrecordings, 2 eachat stations6 and9, and I at station5.

Table 2-6. Approximate timing of deer movementsthrough Solitude Canyon and over Solitude Passduring the spring migrations of 1985-1989and l9g3-lgg4 (Kucera 1985, Taylor 1988.Tavlor 1994). Total Annual Startof Spring End of Spring Year _ Snowfall(in.) Mgration Mgration 198+85 2& 16May 24lune 1985-86 294 25 May 24lune 1986-87 l0l 14May 24lune 1987-88 t43 16May 24lune l9E8-89 186 14May 29 June 1992-93 376 30 May 3 July t993-94 159 22Mav 29 June

DeryscyConshrtim Corpmaum Chspt€r2. SpringMigr*ton SnoutcrcckSki A,eaD€€E Shdv 2-26 It[qEh 1995 Becausethe 35 mm cameraused at station6 wasstolen in earlyJune, before peak migration,very few photographsof deerwere taken. fu a result,this methodprovided little informationregarding the accuracyof the Trailmasteras a deercounting device.

Accordingto radio-telemetryinformation, of the 74 radio-collareddeer on the RoundValley winter rangethat were alive at the endof the springholding period, l5 (20o/o\crossed over SolitudePass (Table 2-5). Usingthe CDFG 1994winter range populationestimate of 1,127deer, the proportionof the deerherd that migratedthrough SolitudeCanyon numbered about 225 animals.Thus, based on telemetrydata it appears thatthe Trailmasterunits at SolitudePass may have overestimated the numberof deerby asmuch as 35o/o. Taylor (1994)identified several inherent problems associated with use of the Trailmasteras a deercounting device. Among thesewere the efus of severe weather,such as high winds andheavy snoudall, that could negativelybias results. Healry snowfallcan cause the Trailmasterto recordphantom events, resulting in countsthat are too high. Conversely,high winds or driftedsnow can force the unitsout of alignment. resultingin countsthat aretoo low. However.these two factorsare in oppositedirections andwould tendto balanceeach other. Thus,based on datacollected from radio-collared deerand the Trailmasterunits, the numberof deermigrating through SolitudeCanyon and over SolitudePass was probablysomewhere between 225 and350 animals.

Deily Timing of Deer Movements. Trailmasterevent data recorded at Solitude Passwas usedto determinethe daily timing of deermovements through the project area (Figure2-13'). Approximately 70oh of eventsoccurred during daylight hours (6 a.m.-8 p.m.);similarly, 8004 of eventsrecorded in 1993occurred between these hours (Taylor 1993). Approximately55o/o of the daytimeevents occurred between 6 a.m.and I I a.m., while 39% occurredbetween I I a.m.and 5 p.m. Forty percentof the nighttimeevents wererecorded between I a.m.and 4 a.m.,and25Yo between l0 p.m.and 12a.m.

Thepropensity of deermoving through the permitarea between the hoursof 6 a.m.and I l. a.m.may be relatedto the physicalcharacteristics of the snowpackat upper elevationsofthe projectarea. Thesurface hardness and density ofthe snowat these highetelevations was greaterin the earlymorning hours following nightswhen temperatureswere below freezing. This hardened crust provided deer increased mobility asthey moved across the snowpack.Verme (1968) observed that hardcrusts allowed deerto roam freely over the snowpack,while weak crustsbroke repeatedly,causing injury andexcessive tiring.

SummerRenges of Radio-CollaredDeer

Of the 66 radio-collareddeer for v;|^ishmigration routes were determine4a total of 3l (47%) summeredeast ofthe Sierracrest, from Lake Sabrinanorth to the Mammoth Lakes. This included7 deerthat usedthe MammothRock and SolitudePass migration routesand summeredin the MammothLakes Basiru which is eastof the Sierracrest, but west ofthe project area. A total of 32 deer(a8%) actuallycrossed the Sierracrest to

Deopscy Cmsmctim Ccprahm Chrytcr2.SpringMgrcim Snmseck Ski Alca De€r Shrdv 2-27 Lirch 1995 t,, IEH[Jo 300 500 700 1100 1300 1500 1700 1900 2100 2300 1600 1800 2000 2200 2400 400 600 800 1000 1200"Hours 1400

Figure2-13. Timingof DeerMovements through the ProiectArea during Sprinq Mioration 1994 westside surnmer ranges. Of these32 deer,29 werefound by CDFGon their summer ranges.A total of 3 deer(5%) diedbefore reaching the summerrange.

Five of the eastside residents summered in the permitarea and vicinity. In addition.a total of 4 unmarkeddeer, all adultfemales, were observed in the permitarea duringfield work conductedfrom Junel5-30. Threeof thesedeer were obsewed in montanechaparral habitat located adjacent to the MammothRock Trail (Table2-7). A fourth deerwas observed in montanechaparral habitat located west of MammothRock. The structuralprofile of montanechaparral vegetation provides suitable fawn rearing habitatfor does. In addition"a numberof the plantspecies associated with the montane chaparralcommunity [e.g., bitterbrush(Pzrsiia tridentata),snowberry (Symphoricarpos vaccinoides),and tobacco brush (Ceanotlrus velutirus\l are recognizedas importantmule deerforages because they arehighly digestibleand contain high levelsof crudeprotein (Ned 1988,Risser and Fry 1988). Summerresident deer use of the SSA permitarea is dependentupon sources of permanent,free water located at HiddenPond, Mammoth Creeh andSherwin Creek.

Table 2-7. Locations and habitatsof 4 adult femalemule deer observedin the Sherwin Ski Area betweenJune l5 and June30 1994 Observation Due DistanceFrom Habitat Number Observed X Coordinate Y Coordinate Water ftm) Twe I 6-16-94 326100 4165500 1.2 MC ) 6-18-94 324200 4164800 0.5 MC J 6-22-94 326900 4165600 0.7 MC 4 6-26-94 325r00 4164800 0.2 MC MC = MontaneChapanal

Road-Kill Data

A total of 9 road-killeddeer from the RoundValley herd were recorded by Caltranscrews on highways203 and395 duringthe 1994spring migration (Table 2-8) (Cdtrans Unpubl. data). In additiorqa total 6 deerwere killed on thesehighways during July-September.Six of the fatalitiesoccurred on Highway203, between post miles 6.0 and8.0, and 9 fatalitiesoccurred on Highway395 between post miles 8.5 and25.5.

Derysey ConstructionCorporatron Chapt€r2. SpringMigrauon Smutrreck Ski Area DeerShdv 2-29 lvftrch 1995 Table2-8. Highwayfatalities recorded by Caltransduring rp.rng and summer 1994. Deer No. Highway PostMile Date Sex Age I 395 9.3 3lt4l94 UID Fawn ) 395 19.0 5/03t94 Female Adult 3 395 24.5 5t23t94 UID Fawn 4 395 25.5 5/29t94 Female Adult ) 395 24.7 6n7t94 Female Adult 6 395 9.4 6lt7/94 Female Adult 7 395 13.5 7lo8l94 Male Adult 8 395 8.5 8l19l94 Female Adult 9 39s . tt.2 9120/94 Female Adult l0 203 E.0 srca94 Female Adult It 203 7.5 5123t94 Male Adult t2 203 6.9 5/23/94 Female Adult l3 203 6.0 6/06t94 Male Adult t4 203 7.8 8/t5/94 Male Adult l5 203 6.8 8/30t94 Female Adult

Dqsery ConstructiooCorpcatrotr Cbaptcr2. SpringMigratim, Snmirrec&Ski ArreiDecr Sfidv 2-30 tvldch t995 Chapter3. Fall Migration

Thischapter describes the resultsof the fall 1994studies.

MIGRATION STUDIES

Timing and Intensityof Migration through the SnowcrcekSki Area

Redio-colhred Deer. Telemetryinformation indicated that fall migrationover the Sierracrest and through fte permitarea lasted from approximatelyOctober 1 to October 16(Figure 3-l). Peakmigration occurred from October5-8, when23 of 28 (82%)radio- collareddeer crossed the Sierracrest. Thesedeer migrated in responseto a snowstonn on October5, whenapproximately 14 centimeters(6 inches)of snowwas recordedat the MammothRanger Station and over a foot of snowfell at the highestelevations of the permit area.

The timing of migrationthrough the permit areaduring fall 1994was similarto othermigrations that occurredin responseto fall snowstorms.In 1984and 1985,deer migratedto the winter rangein Octoberin responseto major fall snowstorms(Kucera 1992). Becauseof the severityof thesestonns, deer hastily vacated the summerrange and migrateden massethrough the project area. In both years,migration to the winter range wascompleted by earlyNovember. Others (Leopold et al. 1951,Bertram and Remple 1977,Lofr.et al. 1989),have also associated the timingof fall migrationwith snowfall.

In comparisorl1986-1988 and 1993were drought years and fall snowstormsdid not occurbefore migration. As a result,deer migrations occurred gradually, lacked any episodesof massmovement, and were extendedinto mid-November(Taylor 1989,Taylor 1993b).Garrott et al. (1987)postulated that deparnrrefrom summerranges in northwest Coloradowas not inducedby snow but insteadby differencesin foragequality between summerand winter ranges.Kucera (1992') suggested that adultfemales may be constrainedin their timing of fall migrationsbecause of smallerbody size,the inability of fawnsto negotiatedeep snow, and the energeticdemands of lactation.

RemoteDeer Counters. The Trailmasterunits at SolitudePass recorded 75 eventsthat could be usedto determinethe timing andintensity of fall deermigration throughthe permit area(Figure 3-2). Deer migrationthrough the permit arealasted for approximately2 weeks,from Octoberl-13. Peakmigration occurred on October6-7, when499lo of all eventswere recorded.

Vcrificetion of l)ecr Counting Accurecy. fluring the 1994fall migration,the Trailmastersat SolitudePass were continuallydisabled because of high winds andblowing

Deqsey Constnrtion Corpcation Cbaptcr3. FaUMigrabm Snourq€ekSki Area Deer Shdv 3-1 I\,ls& 1995 100

90 o 80 o o t, 70 tr o (UE c o 60 o o I C' .9 50 'a E 10 o '6 tr o 40 (L o c '6 30 go o o 5 (L 20

10

0 10t4 10/s 10t6 10n fiB 10/9 10/10 10t12 10/15 10/16 Date

r Percentof Radlo-CollaredDeer Dailyprectpttation rlI - I

Figure3-1. Percent of Radio-CollaredDeer Crossing the SierraGrest in I 16

I I I I 14

12 o c o 10 E t) IU rF o G g o I Eo ct c E a 3 .> z 6 '6 o

4

2

0 10t4 10/5 10t6 fin fin1 10t12 10t13 Date

m ruumberof Events Daily I. - Snowfail(cm). ,l |

Figure3-2. Numberof Eventscounted per Day by theT railmasterUnits at Sofitudepass, l-^ll I l;---ri-- a ?rt\. o c o IU rFo10 o o E zf

ffiffiJm trfl{inilflffi{# ryH

0100 0200 0300 0f0o 0500 0600 0700 ffi-ffif,ffiffi* 1600 1700 1800 1900 m 21c[ 2200 2300 2M

Timingof DeerMovements through the snow. fu a result,most deer were not countedwhen they crossed over SolitudePass. Additionally,many radio-collared deer migrated at nightand were not detecteduntil after theyarrived on the holdingarea or the winter range. Consequently,estimates of the numberof deercrossing over the SolitudePass from comparisonsbetween Trailmaster dataand radio-telemetry data were not possible.

Daity Timing of Deer Movemcnts Eventdata recorded by the Trailmasterunits at SolitudePass was used to determinethe dailytiming of deermovements through the permitarea. Approximately650/o of all evenrswere recorded during the nighttimehours, from 6 p.m.to 7 a.m.(Figure 3-3I In comparison,during fall 1993,approximately 58o/o of the eventsrecorded at SolitudePass occurred during the daytimebetween 7 a.m.and 6 p.m. The differencebetween the two yearsin the dailytiming of deermovements may be relatedto presenceor absenceof fall snowstorms.

DeerComposition Counts

Duringapproximately 100 man-hours field work, a total of I 13 deer(69 females, l1 bucks,and 33 fawns)were classified, yielding a buck/doe/fawnratio of 161100/48 (Table3-l). On October30, 45 deer(25 females,6 males,and 14fawns) were observed on the lavaflats just northof the Mammoth-JuneLakes Airport. Post-season(Janaury) compositioncounts conducted on the RoundValley winter range by CDFGyielded a buck/doe/fawnratio of 241100/34(Vern Bleicb pers.comm.).

Table3-1. Sexand age of deerclassified in the SnowcreekSki Areaand SherwinHolding the 1994fall mierati Date Males Females Fawns B/DIF t0l05/94 0 I 7 0:100:200 rolo8l94 3 l5 J 20:100:20 ro/t0/94 I 5 J 20:100:60 tolt2l94 I 8 ) 12.5:100:25 r0lr3l94 0 l5 9 0:100:60 t0t30t94 6 25 t4 24:100:56 ll 69 33 l6:100:48

Road-Kill Data

Therewere no road-killeddeer from the RoundValley herdrecordd by DCC or Caltransduring the 1994fall migration.

DempscyCondruction Corporauon Cba$cr3. FaUMieratim Smc,qtck Ski Area Decr Shdv 34 It rch 1995 Chapter4. Conclusionsand Recommendations

Radio-TelemetryStudies

DuringJanuary 1994, CDFG capturedand marked an additional50 deer.raising thetotal numberof collareddeer to approximately120 (Vern BleictUCDFG, pers. comm.).These deer will be usedto determinethe locationsof migrationroutes and deer homeranges, and to provideinformation on spatialrelationships, behavior, and energetics. A greaterlevel of efflortwill be requiredin upcomingyears to monitorthis largenumber of radio-collareddeer and successfullycomplete the goalsof the DHMP. Therefore,the hiringof at leastone part-time and two full-timebiologists is recommendedfor the upcoming1995 spring migration.

Becausedeer occupy the SHA for a shortperiod of time (<10 weeks)during the springmrgration, a numberof yearswill be requiredto obtainstatistically vaiid samplesfor estimatinghome range size of manyindividuals. Swihart and Slade (1985) reported that observationsusing a short samplingperiod were autocorrelatedand resultedin an underestimationof homerange size. Theseauthors suggested that whentime and/or manpowerare limited, as they were in this study,I or 2 relocationVanimall24hours will resultin statisticallyvalid samplesfor estimatinghome range size of manyindividuals.

Duringthe 1995spring migration, attempts will be madeto determinethe level of visibilitybias (Samuel et al. 1987)associated with our weeklyroadside surveys. Numerousvariables including animal behavior and dispersiorLtopography, observer experience,goup size, habitatcover types, and weathermay affect the numberof animals observed(Samuel et al. 1987,Davis 1990). Sarnuel et al. (1992)suggested that maintainingstandardized procedures with constantbias will providerelative information on long-termpopuiation trends. Theretbre,future studieswill focuson standardizing thosefactors that canbe controlledby observersand measuring the effectof any uncontrolledbiases on our populationsize estimates. During StageI andII of the DHMP, radio-collareddeer observed during our weekly deercounts will be usedto dwelop a "sightabilityindex". The "sightabilityindex" will be usedin StageIII of the DHMP to estimatethe numberof deeractually on the holdingarea based on the numberof deer observedduring a given ceffils (RaedekeAssociates 1994).

Erbitat Useand SclectionPatterrrs

In spring L994,we usedtelemetry data from 27 radio-collareddeer to estimatea compositehome range that delineatedthe boundariesofthe SHA Theexpected use of habitatwithin the SHA was the proportionaldistribution of habitattypes within the compositehome rangg while the observeduse was basedon the distributionof the telenretrylocations. This approachwas usefulfor deterrrininghabitat preference within the SIIA howwer levelsof habitatselection (Johnson 1980) wef,e not determinedbecause

DanpscyCmstrucuon Ccpcatron Chapt€r4. Conclusionsud Recmendatios SnmcrcckSkiArea D€c( Studv 4-l lv[rrch 1995 we did not havethe time or manpowerto randomlysample plant communities within the holdingarea boundaries. Thus, a priority of springi995 work will be to measurerandom plotslocated within the compositehome range to determinehabitat characteristics (e.g., elevation,slope, aspect. distance to waterand roads, etc.). Thiswill enablethe analysisof secondorder (selection of homerange within the SHA) andthird order(selection of habitatswithin the homerange) habitat selection as described in RaedekeAssociates (lee4).

Trailmasters

Theuse of Trailmastersto countdeer crossing over SolitidePass has worked with mixedsuccess. Taylor (1993)discussed problems inherent in this techniquethat could resultin largeerrors, including the effectsof severeweather (e.g., high winds and drifting snow). Useof a 35 mm camerain conjunctionwith eachTrailmaster unit is the only way to accuratelyverify eventdata (Steve Holl, Jones& StokesAssoc. pers. comm.). However,the theft of our only camerafrom SolitudePass makes this solution impracticable.Because conditions for goodresults are extremely rigorous, it is recommendedthat the countingstations at SolitudePass be checkedevery other day duringpeak migration periods so that adjustmentsand modifications can be madein accordancewith changingenvironmental conditions, e.g., fluctuating snow levels. This levelof effort would requireone part-time employee whose sole job would be to maintain the Trailmastersin operatingcondition.

Deqscy Cmsuctim Corporanon Ch@er 4. Conclusionsand Recmrnendations Somtrrcck Ski Area Deer Stdv +2 lvirEh 1995 Chapter5. Acknowledgements

Thisstudy was conductedunder contract with DempseyConstruction Corporation,Mammoth Lakes. California" with cooperationof a SpecialUse Permit from the U.S.Forest Service, Mammoth Ranger District, Inyo NationalForest. Tim Taylor wasthe projectmanager responsible for the studyand preparation of the report. Karl Changcollected and compiled field dataand helped with the graphics.Dr. Ken Raedeke provideduseful comments on the manuscript.

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