WILDLIFE INFOMETRICS INC. PROGRESS REPORT. Mitigating Risk of Predation for Woodland Caribou in North-central British Columbia MARCH 31, 2007

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1 PROGRESS REPORT Mitigating Risk of Predation for Woodland Caribou in North-central British Columbia R. SCOTT MCNAY 1 AND LINE GIGUERE 1 MARCH 31, Wildlife Infometrics Inc., PO Box 308, Mackenzie, BC, V0J C0, wild_info@wildlifeinfometrics.com Prepared for McGregor Model Forest Association., contract # MMFA - Y (Predation) CITATION: McNay R. S. and L. Giguere Mitigating risk of predation for woodland caribou in north-central British Columbia. Wildlife Infometrics Inc. Report No. 3. Wildlife Infometrics Inc., Mackenzie, British Columbia, Canada. WII Report3_Predation risk annual report_ doc Last printed 5/5/007 5:03 PM

2 ABSTRACT We report on the data collected and progress made during the first year of a 3-year research project established to test the efficacy of using regulated trap-lines to reduce predation risk for threatened herds of woodland caribou in north-central British Columbia. Objectives in the first year included: 1. Peer-reviewed analyses of caribou mortality data and HSM-based predictions of predation risk;. Continued regulated trapping of wolves in one herd area; 3. Continued enhanced harvest of moose in a second herd area 1 ; 4. Augmentation of, and systematic monitoring of, radio-collared animals; and 5. Continued census of caribou, moose, and wolves to obtain estimates of population size and recruitment. A total of 63 wolves have been removed primarily from the removal zone, which includes trapping effort conducted by local trappers prior to official initiation of the project. A further 31 wolf deaths (11 from the removal zone) were derived from screening historic information from monitoring radio-collared wolves in the study areas. Other compiled information to support the study was derived from monitoring radio-collared animals. These data contributed to our understanding of seasonal movements and other ecological factors of relevance and came from monitoring 35, 50, 1, and 36 radiocollared caribou, moose, goats, and wolves, respectively. We investigate a total of 0 mortalities of radio-collared animals during the year. The only collared animal deaths, found in the wolf removal zone, were; 1 wolf, caribou, and 4 goats; the caribou and goats were found just inside the outermost removal zone limit (i.e., 15km from the trapping sites). Three population surveys were conducted to derive population parameters for the caribou herds. Total minimum counts for the Wolverine and Chase herds were 356 and 431, respectively. Several improvements to the study were recognized and recommended for implementation in the subsequent year. 1 Note that this objective will be undertaken by a linked but separate research program. ii

3 ACKNOWLEDGEMENTS We are indebted to Mari Wood (Peace Williston Fish and Wildlife Compensation Program), Chris Johnson (University of Northern BC), and Art Lance (International Forest Services) who provided data on radio-collared caribou preceding our study, which began in Capture and collaring of caribou was undertaken by crews under the management of James Innis and by Bighorn Helicopters (Clay Wilson and crew) and Altoft Helicopter Services (Greg Altoft and crew). Others involved in animal captures were Line Giguere, Glen Watts, Landon Wilson, Keith Connors, Grant Lortie, Gord Carl, Glen Keddie, Shannon Walshe, Brad Culling, Doug Heard, Scott McNay, Jeff Joy, Kathi Zimmerman, and Pam Hengeveld. Aerial support for monitoring radio-collared caribou was performed by Northern Thunderbird Air (Keith Connors, Van Miller, Larry Frey, Leif Scott, John Vandene) and Northern Lights (Eric Steir and Larry Frey). Telemetry biologists included: Mari Wood, Chris Johnson, Line Giguere, Shannon Walshe, Glen Keddie, Landon Wilson, Pam Hengeveld, Emily Muller, Karen Schmidt, Christy Wright, John Miller, Morgan Rankin, Andrew Walker, and Helen Davis. Site investigation was led by Line Giguere with support from Landon Wilson, Shannon Walshe, Glen Keddie, Pam Hengeveld, and Jeff Joy. Viktor Brumovsky provided graphical support and Line Giguere and Jackie Caldwell provided support with data management. This work was funded by Peace Williston Fish and Wildlife Compensation Program, Forest Renewal BC, BC Forest Investment Account (Land Based Investment Program), Slocan Forest Products Ltd. (now Canadian Forest Products, Ltd.), Abitibi Consolidated Company of Canada, and BC Ministry of Environment. We d like to acknowledge the overall support and guidance for the work provided by Doug Heard, Dale Seip, and Rob Serroya. iii

4 TABLE OF CONTENTS ABSTRACT... ii ACKNOWLEDGEMENTS... iii LIST OF tables... v LIST OF FIGURES... v INTRODUCTION... 7 Background... 7 Objective and Expected Outcomes... 8 STUDY AREAS... 9 Wolverine Herd... 9 Chase Herd... 9 METHODS... 9 Regulated wolf trapping and enhanced harvest of moose...11 Caribou mortality investigations...11 Monitoring radio-collared caribou, wolves, and moose...11 Analysis of results...1 Standards...1 RESULTS...13 Regulated wolf trapping...13 Caribou mortality investigations...13 Monitoring radio-collared moose, wolves, and caribou...14 Caribou, moose, and wolf population surveys...16 Recruitment survey late winter (April 006)...19 Recruitment survey fall (November 006)...19 Population and recruitment survey late winter (March 007)...0 DISCUSSION...1 LITERATURE CITED... iv

5 LIST OF TABLES Table 1. Design of spatial and temporal control in an adaptive management project focused on mitigation of predation risk for caribou in north-central British Columbia Table. Number of wolves trapped in the removal treatment zone of the Chase caribou herd area, north-central British Columbia by years prior to (00-006) and after ( ) official start of the wolf removal experiment Table 3. Fate of radio-collared animal by species in the Wolverine and Chase caribou herd areas, north-central British Columbia, March 006 to March Table 4. Total number of relocations of radio-collared animals by species and year within the Wolverine and Chase caribou herd areas in north-central British Columbia Table 5. Selected population parameters from previous surveys of caribou in the Wolverine and Chase herds in the north-central British Columbia. All surveys were conducted during late winter except those indicated by (F) which were fall surveys focused on estimating prewinter recruitment Table 6. Composition of woodland caribou groups observed in the Wolverine and the Chase herd caribou areas during a population survey conducted April 006, in north-central British Columbia Table 7. Composition of woodland caribou groups observed in the Wolverine and Chase caribou herd areas during a population survey conducted November 006, in north-central British Columbia Table 8. Composition of woodland caribou groups observed in the Wolverine and the Chase caribou herd areas during a population survey conducted February-March 007, in north-central British Columbia... 1 LIST OF FIGURES Figure 1. The Wolverine (experimental control), Chase (wolf reduction treatment), and Parsnip (moose reduction treatment) caribou herd recovery planning areas (RPA) located in north-central British Columbia Figure. Trap-line boundaries (left map), wolf removal zone with assumed decreasing zone of effects buffered as 5, 10, and 15 km from the main road/drainage of trapping (yellow shading, both maps), total number of wolves trapped (large bolded numbers) since and, in brackets, the total number of wolves trapped from September - March 007, and wolf pack delineation (right map) derived from relocation of radio-collared wolves from 1996 to 006 (red dots) and radio-collared wolves deaths (green dots) for the Wolverine and Chase caribou herd areas, in north-central British Columbia v

6 Figure 3. Collared animal mortality locations in the Wolverine (experimental control) and Chase (wolf reduction treatment) caribou herd areas and in the wolf removal zone, April March 007 in north-central British Columbia Figure 4. Summer (green dots) and winter (orange dots) distributions of radio-collared woodland caribou (top left), moose (top right), wolf (bottom right), and mountain goat (bottom left) in the Wolverine and the Chase caribou herd areas in the north-central British Columbia, vi

7 INTRODUCTION Background Woodland caribou (Rangifer tarandus caribou) in the Southern Mountain National Ecological Area were designated threatened by COSEWIC in 00, were added to the Species at Risk Act Schedule 1, and are a species at risk under the Forest and Range Practices Act in BC. Caribou are also commonly considered to be a leading indicator of biodiversity and ecosystem health in the boreal and sub-boreal forests (e.g., see ENGO programs such as Caribou Nation, Grey Ghosts 3, and Staring at Extinction 4 ). In the late 1970s, the BC government sensed potential mismanagement of caribou with an apparent decline in populations and annual harvests exceeding 1,500 animals (MacGregor 1985). After curtailing hunting, caribou populations continued to decline and, despite the current legal status, the rate of decline indicates extirpation for many herds in a matter of decades (Wittmer 004). The common denominator in this decline was considered by Messier et al. (004) to be increased ungulate (other than caribou) populations that lead to increased numbers of predators and, hence, increased predation on caribou. Under those conditions caribou apparently suffer more incidental predation from wolves than would otherwise occur (Bergerud 1983, Seip 199, Racey et al. 1999). The increased mortality is exacerbated because caribou are possibly more susceptible to wolf predation than other ungulates (Seip 1991, Seip 199, Thomas 1995). Increases in non-caribou ungulate populations (e.g., moose, deer, and elk) have been related to the abundance of young seral forests resulting from logging (Hatter 1950, Wallmo 1969, Spalding 1990, 199, Rempel et al. 1997, Rettie and Messier 1998). Roads and other linear corridors may also benefit predator search rates and allow predator s access to caribou in places that would otherwise be inaccessible (Jalkotzy et al. 1997; Bradshaw et al. 1997, James and Stuart-Smith 000, Dyer et al. 001). Corrective measures to reverse the decline of caribou therefore must involve predation mitigation either by managing early seral forest conditions, roads and linear corridors, non-caribou ungulates, predators, or a combination of these. Other than the experimental reduction of wolf populations (Elliot 1985, Janz 1989, Seip 199, Boertje et al. 1996, Youds and Roorda 001, Hayes et al. 003), other mitigation techniques have held relatively little attention. Also, there are few published accounts expounding on the relative management efficacy of mitigation techniques other than that of Boertjie et al. (1996) and Hayes et al. (003). Both accounts demonstrate reduced predation rates and more abundant ungulate populations following experimental reduction of wolves. Both accounts also indicate however, that the result is only feasible with considerable long-term effort, the effects of which may ultimately be short-lived. Even so, where recovery of caribou is considered feasible through habitat management, short-term mitigation of predation is still likely to occur while habitat is being restored (MCTAC 003, Seip 005, BCTAC In Prep. 5, McNay et al. Submitted). Mitigation based on reduction of predators is not new but the probable importance of non-caribou ungulates that share their range means the efficacy of predation mitigation remains largely untested and unknown in those circumstances. In collaboration with other partners, we proposed a science-based comparison of predation mitigation using a combination of Boreal Caribou Technical Advisory Committee. In prep. A Recovery Strategy for Boreal Caribou in British Columbia Draft#. Ministry of Water, Land and Air Protection, Victoria, B.C. 7

8 Habitat Supply Modeling (HSM) and adaptive management in north-central BC. In that area, previous studies of radio-collared caribou, moose (Alces alces (Linnaeus, 1758)), and wolves in three caribou herds, enabled us to opportunistically compare efficacy of: 1) regulated trapping of wolves and ) an enhanced hunter-harvest of moose. Regulated wolf trapping occurred and is continuing in one herd area while an enhanced harvest of moose was initiated in another herd area. The third herd area acts as the spatial control. The question we specifically addressed was; can sufficient reduction in predation risk be achieved through regulated trapping to avoid special regulatory policy on reductions of wolves for the purpose of caribou recovery? We assumed predation risk to be defined as the probability of caribou encountering, or being killed by, predators (Lima and Dill 1990). Based on previous investigations, caribou survival and mortality rates (McNay and Voller In prep. 6 ) and modeling of caribou habitat supply (McNay et al. 006), we predicted that removal of wolves adjacent to caribou migration routes would be most beneficial to caribou and more likely to temporarily reduce adult mortality than if trapping were to occur without this focus. In support of this prediction, our observations seemed to indicate that, most caribou mortality was by predation and that most predation was by wolves (McNay and Voller In prep. 7 ). Furthermore, predation appeared to occur mostly during migration (McNay and Voller In prep. 8 ) therefore it seemed likely that most predation related deaths should be where migration routes intersect local areas of high use by wolves (i.e., places of high predation risk). Objective and Expected Outcomes Objectives in the first year included: 1. Peer-reviewed analyses of caribou mortality data and HSM-based predictions of predation risk;. Continued regulated trapping of wolves in one herd area; 3. Continued enhanced harvest of moose in a second herd area 9 ; 4. Augmentation of, and systematic monitoring of, radio-collared animals; and 5. Continued census of caribou, moose, and wolves to obtain estimates of population size and recruitment. Work in subsequent years would include: 6. Continued monitoring of, and augmentation of, collared animals; 7. Comparative analysis focused on efficacy of predation mitigation; 8. Recommendations for adaptation in management where indicated by results; and 9. Development of long- and short-term strategies for mitigating risk of predation. Our objectives were primarily focused on efficacy of predation mitigation through regular activities on a registered trap line. In Year 1, we began monitoring the effects of the trapping activities as they pertained to reduction of wolves and the subsequent effect on survival of caribou compared to that experienced in the control herd where no trapping occurred. The treatment based on reducing moose populations was the primary objective being addressed by a collaborative project under the management of the 6 McNay, R.S. and J. Voller. In prep. Mortality- and survival-rate estimates for woodland caribou in north-central British Columbia. Canadian Journal of Zoology. XX:XXX-XXX. 7 Ibid. 8 Ibid. 9 Note that this objective will be undertaken by a linked but separate research program. 8

9 Peace Williston Fish and Wildlife Compensation Program (Doug Heard; pers. comm.; March 006). That team began measuring the effects of moose reduction as it pertained to minimizing the ability for wolves to have incidental contact with caribou; and therefore having the ultimate effect of reducing caribou mortality rates. Results from that project are reported under the Peace Williston Fish and Wildlife Compensation Program. STUDY AREAS The study area was the recovery planning area for the Wolverine, Chase, and Parsnip caribou herds (Figure 1). The area spanned the boundary between the Northern and Southern Mountains National Ecological Areas in north-central British Columbia north from the headwaters of the Parsnip River, throughout the Rocky Mountain foothills on the east side of Williston Reservoir, and in the Omineca Mountains on the west side of Williston Reservoir north to the Ingenika River. The Parsnip study area was described in detail by Walker et al. (006). Wolverine Herd The Wolverine RPA is 844,313 ha, ranging in elevation from 676 to 134 m in rolling high-elevation foothills, and includes four major watersheds of the Omineca, Manson, Klawli, and Germansen Rivers (Figure 1). It is roughly bounded in the north by the headwaters of Goat, Nina, and Big Creeks, in the west by Takla, Tsayta, and Indata lakes, in the south by Tchentlo and Chuchi lakes, and in the east by Sylvester and Gaffney creeks, and the eastern slopes of the Wolverine Mountain Range. At low- to mid-elevations, the area is dominated by a Boreal White and Black Spruce zone (BWBSdk1 the specific subzone variant), two of the Sub-Boreal Spruce subzone variants (SBSmk1 and SBSmk), and an Engelmann Spruce-Subalpine Fir zone (ESSFmv3 the specific variant) dominates the mid- to high-elevations. The Alpine Tundra (AT) prevails above tree line. Chase Herd The Chase RPA is 1,733,039 ha situated in steep mountainous terrain ranging in elevation from 671 to 466 m, and has three major watersheds including the Ingenika, Osilinka, and Mesilinka Rivers (Figure 1). It is roughly bounded in the north by the most northerly portion of the Finlay River, in the west by Thutade, Sustut and Driftwood rivers, in the south by Ominicetla Creek, back end of Osilinka River, headwater of Wasi and Flegezand creeks, and in the east by the Williston Reservoir. At low- to mid-elevations, the area is dominated by the BWBSdk1 and SBSmk subzone variants, and at mid- to high-elevations the ESSFmv3 subzone variant predominates. The Alpine Tundra (At) prevails above the tree line. METHODS The design we implemented was largely based on the concepts of adaptive management or large operational trials (Walters and Holling 1990) using techniques forwarded by Nyberg (1999) and Taylor and Nyberg (1999). In these designs: 9

10 Figure 1. The Wolverine (experimental control), Chase (wolf reduction treatment), and Parsnip (moose reduction treatment) caribou herd recovery planning areas (RPA) located in north-central British Columbia. 1) treatments are employed; ) results monitored and compared against controls, other treatments, and objectives; and 3) when necessary, management activities are adjusted through time in ways that bring results closer to overall goals and objectives. The treatments we employed were regulated wolf trapping and, through a collaborative project, enhanced moose harvest. Monitoring was conducted through: 1) aerial telemetry of radio-collared caribou, wolves, and non-caribou ungulates (primarily moose), ) regular population surveys of caribou and moose, and 3) investigations of mortalities to determine timing and cause of death. Based on results, we considered that mitigation of predation risk for caribou, may possibly be adapted by means of where, and/or in what magnitude, mitigating actions are applied. We had the unusual opportunity to provide controls (Table 1) for this experiment both spatially (i.e., the Wolverine herd) and temporally (i.e., data collection prior to treatment in all areas) 10

11 Table 1. Design of spatial and temporal control in an adaptive management project focused on mitigation of predation risk for caribou in north-central British Columbia. Herd Area Parsnip Wolverine Chase Mitigation technique Enhanced harvest of moose No special management Regulated trapping Year started 005 NA 004 Caribou study a a All areas currently have radio-collared caribou. allowing for an assessment of efficacy of the treatments in reducing risk of predation for caribou. Replication for this large-scale experiment was not possible but can be partially inferred from a similar project in the Revelstoke recovery planning area 10. Even so, replication is incomplete because the Revelstoke study has been focused solely on an enhanced harvest of moose. Regulated wolf trapping and enhanced harvest of moose Integrity of the adaptive management design was insured by implementing treatments through standard management mechanisms (i.e., regulated registered traplines and regulated hunting through the provincial Limited Entry Hunt program). We expected to be able to implement adaptation to treatments depending on monitoring results. If, and when, changes to treatments occurred, they were recorded as part of the overall design. For example, regulated trapping was guided to specific portions of the trap line predicted to be high predation risk (i.e., based on habitat modeling predictions and monitored observations of wolves). Caribou mortality investigations Age-based mortality rates were assessed by investigating mortality of radio-collared caribou. We used logistic regression to estimate annual mortality and to investigate significantly related mortality factors where the binomial condition of a radio-collared animals state (i.e., alive or dead) was used to identify environmental conditions that helped explain patterns in the observed mortality. For this analysis we investigated each death of radio-collared caribou to assess potentially related mortality factors including: animal age/gender class, general body condition, snow depths, habitat type (e.g., forest cover, elevation, aspect, ecological site association), and time (e.g., year, month) and cause of death. We also used opportunistic observations (i.e., mortality investigations, telemetry flights, census surveys, local knowledge from trappers, hunter, and local residents) of any ungulate mortality to assess spatial and temporal relationships with distribution of caribou and spatially-explicit zones of modeled predation risk. Monitoring radio-collared caribou, wolves, and moose Other key monitoring variables in this adaptive management design were population parameters of caribou, moose, and wolves. Relocation of animals equipped with radiocollars increased the effectiveness and accuracy of monitoring these parameters in general and was therefore a fundamental component of our adaptive management plan. 10 See Forest Science Program Y

12 We attempted to augment our sample of collared animals in all three study areas to a minimum of 0 caribou each. We tracked wolf packs in the Chase and Wolverine herd areas by attempting to place collars on individuals from each pack where location of these packs were inferred from our own historic data collection in the study areas. We considered it unnecessary to radio-collar non-caribou ungulates although we had a small sample of moose (n = 10) and mountain goats (n = 50) as a means to explore range segregation and overlap with caribou and wolves. Radio-collars were placed on animals using aerial capture techniques (i.e., net-gunning) conducted during winter. All animal captures were conducted under licensed permit to the Min. of Environment. Population parameters (i.e., total size, gender/age classes, and juvenile recruitment) were estimated from annual surveys of: caribou in all study areas, moose in the Parsnip and Wolverine areas, and wolves in the Chase and Wolverine areas. These census operations were conducted during late winter because animals tended to be concentrated then and were therefore easier to observe compared to other times. Also, gender could be confirmed more reliably, and juvenile recruitment was more accurately measured. During that time most caribou moved to high-elevation winter range and foraged in open alpine so the census technique was conducted as a total count. Moose were surveyed using a stratified random sample of early seral and riparian forests below 100 m asl. Wolves were surveyed opportunistically during caribou and moose surveys. We also relied on direct observation (loggers, truckers, trappers, local residents, and telemetry flights) to enumerate and characterize wolf pack dynamics. While census surveys were conducted once per year in the Chase and Wolverine areas, caribou were also surveyed during fall for an interim (i.e., after the summer season) measure of recruitment. Caribou were surveyed in late winter in the Parsnip area (pers. com.; Doug Heard, December 08, 005) because the primary hypothesis predicts most caribou morality to occur during summer. Analysis of results In subsequent years of this study, annual population parameters from the control area will be compared to those of the treatment areas in paired-comparisons (Zar 1997) stratified by pre- and post-treatment periods. Post-treatment response will be detected as significant (P =.05) departures from the control parameters noted through the pairedcomparison. Comparison among spatial parameters will be assessed using standard F- tests (Zar 1997). Standards A number of standards for the proposed sampling were applied as follows: Species Inventory Fundamentals Standards for Components of British Columbia's Biodiversity No.1; Aerial-Based Inventory Methods for Selected Ungulates Standards for Components of British Columbia's Biodiversity No. 3; Inventory Methods for Wolf and Cougar Standards for Components of British Columbia's Biodiversity No. 34; Wildlife Radio-telemetry Standards for Components of British Columbia's Biodiversity No. 5; 1

13 Live Animal Capture and Handling Guidelines for Wild Mammals, Birds, Amphibians & Reptiles Standards for Components of British Columbia's Biodiversity No.3; and Voucher Specimen Collection, Preparation, Identification and Storage Protocol: Animals Standards for Components of British Columbia's Biodiversity No. 4a. RESULTS Regulated wolf trapping The Chase caribou herd wolf removal zone, contained 1 whole, and portions of 6 other, regulated registered trap-lines (Figure, left map). As far as we know, only one of the trap-lines (TR ) was operated regularly (i.e., annually). This regularly operated trap-line consisted of approximately 50% of the total removal area (based on linear area). The number of trapped wolves and wolverines, from 1999 to 005, reported from Government (Pers. Comm.; Eric Lofroth; April, 005) was 1 and 8 (Wolverine herd area) and 10 and 13 (Chase herd area), respectively. The 10 wolves reported from the Chase caribou area were considered to originate from the removal zone. Information collected directly from trappers confirmed that a total of 63 wolves (Table ) were trapped in the removal zone of the Chase caribou herd since Twentyfour of these removed wolves were trapped this past winter From our best knowledge of wolf pack distribution, 46 % of these removals possibly belonged to the Osi wolf pack, 4% to the Osi, Blu, or Mes packs, 19 % to the Osi or Omi pack, 6% to the Heli pack, and 5% to the Mes pack (Figure, right map). Other information pertaining to wolf mortality was derived from monitoring the fate of radio-collared wolves (n=44) since We were able to screen data for 36 of these wolves that were last recorded within the study areas ( in the Wolverine and 14 in the Chase caribou herd areas). Sixteen of these final relocations came from the removal zone and were diagnosed as follows (Figure, right map): 5 deaths by hunting/trapping (which we assumed were accounted for in (Table ), 1 hit by a vehicle, unknown mortality causes, and 8 collars faded so ultimate fate of the wolves was unknown. Anecdotal information from First Nation people also revealed that other wolves and wolverine were taken from the Chase caribou herd area however, we have yet to confirm the timing, removal location, and exact number. Also, it is common knowledge that some wolves were shot opportunistically in the Wolverine caribou herd area but we believe this to be a relatively small number. More precise information concerning this removal will be determined in subsequent years. Caribou mortality investigations Our screening of data from 0 radio-collared animal status changes (March 006 to March 007) revealed; 1 caribou, 1 moose, 6 goats, and 1 wolf changes (Table 3). Of the 1 caribou, 10 were field-investigated where we concluded that 7 mortalities were cause by predation (5 in the Wolverine and in the Chase herd areas), were dropped collars (1 in Wolverine and 1 in Chase herd areas), and 1 was caused by hunter-kill in 13

14 Figure. Trap-line boundaries (left map), wolf removal zone with assumed decreasing zone of effects buffered as 5, 10, and 15 km from the main road/drainage of trapping (yellow shading, both maps), total number of wolves trapped (large bolded numbers) since and, in brackets, the total number of wolves trapped from September - March 007, and wolf pack delineation (right map) derived from relocation of radio-collared wolves from 1996 to 006 (red dots) and radio-collared wolves deaths (green dots) for the Wolverine and Chase caribou herd areas, in north-central British Columbia. the Chase herd area (1 mature male). The caribou not field investigated are noted as unknown cause of death where one collar (Wolverine area) stopped emitting a signal and the other investigation (Chase area) was omitted due to time and budget constraints. Of the 6 goats discovered on mortality signal, all from the Chase area, 5 were believed to have died due to avalanches (recorded as Accident/Nutrition) and 1 was reported as unknown since no investigation was conducted due to safety hazard (high risk of avalanche when discovered). The only radio-collared moose reported dead (from the Wolverine caribou herd area) was due to regulated hunting. The death of the radio-collared wolf from the Chase area was attributed to a vehicle hit or a hunter kill. The wolf carcass was sent for a necropsy, which resulted in inconclusive results. The date of death for the 7 caribou mortalities caused by predation (3 by wolf, 1 suspect by wolf, suspect by grizzly bear, and 1 unknown predation), were estimated to be from early April to end of June ( by grizzly and by wolf), from mid-may to mid-september (1 by wolf), from early February to early March (1 unknown predation), and from early December to end of February (1 by wolf). The only collared animal deaths, found in the wolf removal zone, were; 1 wolf, caribou, and 4 goats; the caribou and goats were found just inside the outermost removal zone limit (Figure 3). As a component of this investigation, we conducted more detailed investigations of mortality and survival rates (McNay and Voller in prep 11 ) and on the spatial patterns of predation risk (McNay 007). Monitoring radio-collared moose, wolves, and caribou Seasonal range distribution for caribou, moose, goats, and wolves within the study areas is provided in Figure 4. Information upon which to understand these seasonal 11 McNay, R.S. and J. Voller. In prep. Mortality- and survival-rate estimates for woodland caribou in north-central British Columbia. Canadian Journal of Zoology. XX:XXX-XXX. 14

15 Table. Number of wolves trapped in the removal treatment zone of the Chase caribou herd area, north-central British Columbia by years prior to (00-006) and after ( ) official start of the wolf removal experiment. Year Trapping Site Location Number of wolf captured from trapping < 1 yr < yr 3-4 yr 4-6 yr 3-8 yr > 8 yr Unk F M U F M U F M U F M U F M U F M U F M U Total Osilinka Osilinka Osilinka km Mes Air km km Total Aiken End Lk Mes Air km km Mes Bridge Total All Years Total Gender: F for female, M for male, U for unknown gender; Age: Unk for unknown gender Table 3. Fate of radio-collared animal by species in the Wolverine and Chase caribou herd areas, north-central British Columbia, March 006 to March 007. Number of Mortality Sites Investigated Herd Area Fate Caribou Moose Goat Wolf Total Predation 5(3) a Accident/Nutrition Wolverine Human Dropped Collar Unknown Predation (1) Accident/Nutrition Chase Human Dropped Collar Unknown Predation Accident/Nutrition Total Human Dropped Collar Unknown Total a Numbers in bracket indicate the number of mortality originated prior winter

16 Figure 3. Collared animal mortality locations in the Wolverine (light green - experimental control) and Chase (darker green - wolf reduction treatment) caribou herd areas and in the wolf removal zone, April March 007 in north-central British Columbia. movements and other ecological factors of relevance has come from 35, 50, 1, and 36 radio-collared caribou, moose, goats, and wolves, respectively (Table 4). Caribou, moose, and wolf population surveys We conducted 3 individual surveys of caribou and wolves during the past fiscal year. These surveys were focused on post-winter 006 caribou juvenile recruitment in the Wolverine herd area, a fall 006 caribou survey in both the Wolverine and Chase herd areas to estimate pre-winter recruitment, and a late winter 007 caribou survey in both the Wolverine and Chase areas to estimate total population and post-winter recruitment. The post-winter 006 juvenile recruitment survey in the Chase area had already been completed for the Chase herd area (Unpubl. data; Wildlife Infometrics Inc., Mackenzie, BC). A summary of these survey results and other relevant results from historic surveys is presented in Table 5. During these surveys we had several opportunities to observe wolf packs that had yet to 16

17 Figure 4. Summer (green dots) and winter (orange dots) distributions of radio-collared woodland caribou (top left), moose (top right), wolf (bottom right), and mountain goat (bottom left) in the Wolverine and the Chase caribou herd areas in the north-central British Columbia,

18 MCNAY AND GIGUERE WILDLIFE INFOMETRICS INC Table 4. Total number of relocations of radio-collared animals by species and year within the Wolverine and Chase caribou herd areas in north-central British Columbia. Species Area Wolverine Caribou Chase Total relocations Total animals Wolverine Moose Chase Total relocations Total animals Wolverine Goat Chase Total relocations Total animals Year Total Wolverine Wolf Chase Total relocations Total animals Animals

19 Table 5. Selected population parameters from previous surveys of caribou in the Wolverine and Chase herds in the north-central British Columbia. All surveys were conducted during late winter except those indicated by (F) which were fall surveys focused on estimating prewinter recruitment. Recovery Planning Area Year Total Counted Calves/100 Cows Calves/% of Pop. Bulls/100 Cows Reference Wolverine b Hatler b c Wood c Hengeveld and Wood a Zimmerman et al a c Zimmerman et al a Zimmerman et al a Wilson et al Unpublished data 006 (F) Unpublished data a,b Giguere and McNay 007 Chase b Corbould a Zimmerman et al a c Zimmerman et al a c Zimmerman et al McNay and Giguere (F) Unpublished data a,b Giguere and McNay 007 a attempted full counts (assuming current recovery planning areas) b relatively severe winter weather compared to average c suspect ratio of males to females which could alter the calf/100 cow estimate be collared. Repeated observation of these packs by independent observers conducted over the multiple surveys was used to provide general estimates of pack size and distribution. We estimate pack sizes as follows: Blu (), Osi (1-); Omi (>8, maybe as high as 0; Mes (0), Heli (~10), Iso (4-5), Ing (unk), Bla (8-10), Kla (unk), Val (unk). Results of the moose surveys have been reported elsewhere by Walker et al. (006). Reports focused on surveys of caribou and moose for the companion study in the Parsnip study area were provided by Heard and Watts (007) and by Seip et al. (007), respectively. Recruitment survey late winter (April 006) During April 006, using 7 hours of helicopter services, we surveyed parts of the Wolverine herd area to estimate calf recruitment. We found 4% of the population sampled (n = 197) to be calves (Table 6). We were unable to calculate calves/100 cows because we did not adequate spend time to determine sex of adults. Recruitment survey fall (November 006) During November 006, using 1.5 hours of helicopter services, we surveyed parts of the Wolverine and Chase herd areas to estimate pre-winter calf recruitment. We found 19

20 % of the population sampled (n = 138) to be calves in the Wolverine herd area and 11% of 16 animals observed in the Chase herd area (Table 7). Table 6. Composition of woodland caribou groups observed in the Wolverine and the Chase herd caribou areas during a population survey conducted April 006, in north-central British Columbia. Herd Strata Group Adult Male Adult Male Mature Adult Male Young Adult Female High 19 a Wolverine Low Total a Three of 19 groups observed in High elevation strata were located in the overlap zone between the Wolverine and Chase herd area. Table 7. Composition of woodland caribou groups observed in the Wolverine and Chase caribou herd areas during a population survey conducted November 006, in north-central British Columbia. Adult Unknown Juvenile Calf Unknown Total Bulls / 100 Cows Calves / 100 Cows Calves % of Population Herd Strata Group Adult Male Adult Male Mature Adult Male Young Adult Female High Wolverine Low Total High Chase Low Total High Total Low Total Adult Unknown Juvenile Calf Unknown Total Bulls / 100 Cows Calves / 100 Cows Calves % of Population Population and recruitment survey late winter (March 007) We surveyed the Wolverine and the Chase caribou herd areas during March 007 (Giguere and McNay 007). We located 134 groups of caribou for a total count of 787 0

21 individuals distributed throughout the study areas (Table 8). The ratio of caribou bull to cows for the Wolverine was 66:100 and 7:100 for the Chase. The ratio of caribou calf to cows and the calves as percent of the population was 34:100 and 15% in the Wolverine area and 31:100 and 14% in the Chase area. Group sizes varied from single animals to, in one case, a group of 9; the latter observed in the Chase area. Groups were commonly (36% of the observations) -4 animals. In the Chase area, there were 7 groups >15 animals while only 1 group >15 was observed in the Wolverine area. Table 8. Composition of woodland caribou groups observed in the Wolverine and the Chase caribou herd areas during a population survey conducted February-March 007, in north-central British Columbia. Herd Strata Groups Adult Male Adult Female Adult Unknown High Wolverine Low 0 Total High Chase Low Total High Sub-Total Low Total a % Calves does not include Unknown animals. Juvenile Calf Unknown Total Bulls/100 Cows Calves/100 Cows % Calves a DISCUSSION Because this was the first year of the study, we were unable to draw many conclusions about treatment (i.e., regulated trapping of wolves or the enhanced harvest of moose) effects as they may have occurred. This comparison will be the focus of the annual report in subsequent years where indicators (i.e., population parameters of moose and caribou; mortality statistics for caribou, moose, and wolves; and spatial distribution of caribou, moose, and wolves) will be assessed for the two treatment areas and the experimental control area. We did note in the population surveys this year that caribou calf recruitment seemed to be higher in the Chase area but the spatial extent of the results was more restricted than expected. The resolution required to identify the treatment effect in the late-winter survey may also explain the apparent inconsistency between the fall recruitment in the Chase area (11%) and the subsequent estimate for late-winter (14%). We need to look deeper into this and, if necessary, amend the sample design for next year to either incorporate larger distribution of sampling, larger sample sizes, or both. 1

22 Additional data collection is required for wolf population status throughout the study zone (possibly incorporating a systematic survey of tracks in winter) and an effort to retrieve historical data on removal of wolves in both the removal treatment (i.e., Chase) and experimental control (i.e., Wolverine) zones through visits and interviews of trappers and other First Nations and public. We also require more wolf packs to be collared for the purposes of monitoring seasonal distribution and kill rates. This could involve an amendment to the project design to include trapping during summer months. LITERATURE CITED Bergerud, A. T The natural population control of caribou. Pp In F. L. Bunnell, D. S. Eastman, and J. M. Peek (Co-editors) Symposium on natural regulation of wildlife populations. Forest, Wildlife, and Range Experiment Station, University of Idaho, Moscow, Idaho, USA. 5pp. Boertje, R., P. Valkenburg, and M. McNay Increases in moose, caribou, and wolves following wolf control in Alaska. J. Wildl. Manage. 60: Bradshaw, C.A., S. Boutin and D.M. Hebert Effects of petroleum exploration on woodland caribou in northeastern Alberta. J. Wildl. Manage. 61: Corbould, F.B Chase Mountain/Butler Range Caribou Inventory, March Peace/Williston Fish and Wildlife Compensation Program, Report No. 6. 3pp plus appendices. Dyer, S.J., J.P. O Neill, S.M. Wasel, and S. Boutin Avoidance of industrial development by woodland caribou. J. Wildl. Manage. 65: Elliot, J Muskwa wolf management project of north-eastern BC: Wolf/ungulate management annual report. British Columbia Min. of Environment, Ft. St. John, British Columbia. 44pp. Giguere L. and R. S. McNay Abundance and distribution of woodland caribou in the Chase, Wolverine, and Scott recovery plan areas. Wildlife Infometrics Inc. Report No. 5. Wildlife Infometrics Inc., Mackenzie, British Columbia, Canada. Hatler, D.F Moose winter distribution and habitat use in the southern Williston Reservoir area, British Columber, Peace/Williston Fish and Wildlife Compensation Program Report No. 1. 5pp plus appendices. Hatter, J The moose of central British Columbia. Dissertation, State College of Washington, Pullman, Washington. Hayes, R.D., R. Farnell, R.M.P. Ward, J. Carey, M. Dehn, G.W. Kuzyk, A. M. Baer, C.L. Gardner, and M. O Donoghue Experimental reduction of wolves in the Yukon: Ungulate responses and management implications. Wildlife Monographs pp.

23 Heard, D.C. and G.S. Watts Prince George and Parsnip Moose composition survey December 006. Internal Rept., British Columbia Ministry of Environment, Peace Region, Prince George, BC Hengeveld, P.E. and M.D. Wood Wolverine Caribou Herd Winter Survey Peace/Williston Fish & Wildlife Compensation Program, Report No pp plus appendices. Jalkotzy, M.G., P.I. Ross, and M.D. Nasserden The effects of linerar developments on wildlife: A review of selected scientific literature. Prepared for the Can. Assoc. of Petroleum Producers. Arc Wildlife Services Ltd., Calgary, Alberta. 115pp. James, A.R.C. and A.K. Stuart Smith Distribution of caribou and wolves in relation to linear corridors. J. Wildl. Manage. 64: Janz, D Wolf-deer interactions on Vancouver Island. In Wolf prey dynamics and management, proceedings of a symposium May 1988, Univ. of British Columbia. BC Min. of Enviornment Report No. WR-40, Min. of Environment, Victoria, BC. Lima, S. L. and DL.M. Dill Behavioral decisions made under the risk of predation: a review and prospectus. Canadian Journal of Zoology 68: MacGregor, W Provincial and regional caribou plans. Pp. -8, In R. Page (Ed.) Caribou research and management in British Columbia. British Columbia Min. of For., Res. Br., WHR-7, Victoria, BC 68pp. McNay, R.S Spatial characteristics of predation risk for woodland caribou in north-central British Columbia. Wildlife Infometrics Inc. Report No. 33. Wildlife Infometrics Inc., Mackenzie, British Columbia, Canada. McNay, R. S. and L. Giguere An aerial survey of northern caribou in the Chase herd area. Wildlife Infometrics Inc. Report No Wildlife Infometrics Inc., Mackenzie, British Columbia, Canada. McNay, R.S., B.G. Marcot, V. Brumovsky, and R. Ellis A Bayesian approach to evaluating habitat suitability for woodland caribou in north-central British Columbia. Can. J. For. Res. 36: MCTAC A strategy for the recovery of mountain caribou in British Columbia. British Columbia Min. of Water, Land, and Air Protection, Victoria, BC. Messier, F., S. Boutin, and D. Heard Revelstoke mountain caribou recovery: An independent review of predator-prey-habitat interactions. Unpubl. Rep., Revelstoke Caribou Recovery Committee, Revelstoke, British Columbia. 1pp. Nyberg, B An introductory guide to adaptive management for project leaders and participants. British Columbia Min. of For., Forest Practices Branch, Victoria, BC. 0pp. 3

24 Racey, G., A. Harris, L. Gerrish, T. Armstrong, J. McNicol, and J. Baker Forest management guidelines for the conservation of Woodland Caribou: a landscape approach for use in northwestern Ontario. Version 1.0 Ontario Min. of Nat. Resource., Thunder Bay, Ontario. 69pp.Seip,D.R Factors limiting woodland caribou populations and their interrelationships with wolves and moose in southeastern B.C. Can. J. Zool. 70: Rempel, R. S., P. C. Elkie, A. R. Rodgers, and M. J. Gluck Timber-management and natural-disturbance effects on moose habitat: landscape evaluation. Journal of Wildlife Management 61: Rettie, W. J., and F. Messier Dynamics of woodland caribou populations at the southern limit of their range in Saskatchewan. Canadian Journal of Zoology 76: Seip, D Recovery implementation planfor threatened woodland caribou (Rangifer tarandus caribou) in the Hart and Cariboo Mountains recovery area, British Columbia. Internal Report, Species at Risk Coordination Office, British Columbia Min. of Agriculture and Land, Victoria, BC Factors limiting woodland caribou populations and their interrelationships with wolves and moose in southeastern British Columbia. Can. J. Zool. 70: Predation and caribou populations. Rangifer Special Issue 7:46-5., D. Heard, and D. Wilson Mountain caribou census in the Parsnip watershed March 007. Internal Rept., British Columbia Min. of Forests, Prince George, BC Spalding, D. J The early history of moose (Alces alces): distribution and relative abundance in British Columbia. Contributions to Natural Science No. 11, The Royal British Columbia Museum, Victoria, British Columbia The history of elk (Cervus elaphus) in British Columbia. Contributions to Natural Science No. 18, The Royal British Columbia Museum, Victoria, British Columbia. Taylor, B. and B. Nyberg An introductory guide to adaptive management for project leaders and participants. British Columbia Min. of For., Forest Practices Branch, Victoria, BC. 0pp. Thomas, D. C A review of wolf-caribou relationships and conservation implications in Canada. Pages in: L. N. Carbyn, S. H. Fritts, and D. R. Seip, editors. Ecology and conservation of wolves in a changing world. Proceedings of the Second North American Symposium on Wolves, Edmonton, Alberta, 5-7 August 199. Occasional Paper No. 35, Canadian Circumpolar Institute, Edmonton, Alberta. 4

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