MULE DEER BUCK MIGRATIONS AND HABITAT USE IN THE BRIDGE RIVER, BRITISH COLUMBIA (FWCP Project # 11.W.BRG.05)

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1 MULE DEER BUCK MIGRATIONS AND HABITAT USE IN THE BRIDGE RIVER, BRITISH COLUMBIA (FWCP Project # 11.W.BRG.05) Prepared by: Chris Procter, R.P.Bio Francis Iredale, R.P.Bio Doug Jury, R.P.Bio Ministry of Forests, Lands & Natural Resource Operations Fish & Wildlife Kamloops, BC & Matt Manual Lillooet Tribal Council Lillooet, BC March 31, 2012

2 EXECUTIVE SUMMARY In recent years, both the Ministry of Forests, Lands and Natural Resource Operations (MFLNRO) and the St at imc First Nation have become concerned with the status of the mule deer population west of the Fraser in southcentral British Columbia. These concerns provided the impetus for the recently completed two years of research on the female components of the deer population in the St at imc territory. This project seeks to build and expand on that data set by investigating habitat use and migration ecology of mule deer bucks in the area to provide further information on this population that can be applied to deer management. The primary purpose of this report is to report results achieved in the first year of the project. During April and May 2011, 9 mule deer bucks were captured and collared in the study area through free-range chemical immobilization. Collared deer were monitored through out the year to assess survival status and approximate distribution. Collars are set to be retrieved in mid to late April and early May when deer return to their low elevation spring ranges. Three collars from legally harvested bucks during the fall hunting season have been retrieved. Ground and aerial monitoring revealed that all deer migrated from their winter/spring ranges to distant summer ranges. Most migrated west and summered in the vicinity of Goldbridge and lower reaches of several drainages in the area. A couple of other bucks migrated north and south and summered in alpine habitat. Collars from all bucks need to be retrieved to confirm these general observations. i

3 TABLE OF CONTENTS LIST OF FIGURES... iii LIST OF TABLES... iv 1. INTRODUCTION GOALS & OBJECTIVES STUDY AREA METHODS RESULTS DISCUSSION RECOMMENDATIONS ACKNOWLEDGEMENTS REFERENCES APPENDIX ii

4 LIST OF FIGURES FIGURE 1. Map of study area... 2 iii

5 LIST OF TABLES TABLE 1. Statistics for mule deer bucks captured in the study area spring iv

6 1. INTRODUCTION In recent years, the St at imc Nation has become concerned that deer within their traditional territory, west of the Fraser River in south central British Columbia, are experiencing a negative population trend. Unpublished data from the Fish, Wildlife and Habitat Management Branch (FWHMB), Ministry of Forests, Lands & Natural Resource Operations (MFLNRO), supports the notion that deer have experienced a decline since the early 1990 s in the area. Overall, although deer numbers have rebounded from earlier declines, they continue to remain below levels seen in the 1960s and 1970s (Hatter et al. 1989). While causes for these declines are not known with certainty and are likely the result of several different factors relating to habitat and direct mortality, broad scale landscape changes from timber harvests and hydroelectric development have contributed, and in some cases, are likely still contributing. These concerns provided the impetus for the recently completed two years of research on the female components of the deer population in the St at imc territory (i.e., Poole and Wright 2010). This project seeks to build and expand on that data set by examining the buck component of this mule deer population. Information on habitat use and migration ecology of mule deer bucks is essential to ensure sound management (Brown 1992; Kie et al. 2002; Walter et al. 2009; Sawyer et al. 2009). 2. GOALS & OBJECTIVES The overall goal of this project is to investigate mule deer buck habitat use and migration ecology to provide information to enhance harvest and habitat management of the deer population in the Bridge River drainage. This will be accomplished through 8 long-term objectives: 1. Assess residency patterns (i.e., resident vs. migratory) of bucks. 2. Describe habitat characteristics of mule deer buck seasonal ranges (summer, fall, rut, winter and spring). 3. For migratory bucks, describe mule deer buck migration patterns, including timing and movement routes between seasonal ranges. 4. For migratory bucks, describe habitat selection during spring and fall migrations and understand why bucks selected those habitats. 5. Describe daily habitat use and movement patterns of bucks and does during November 10 to December Compare winter ranges utilized by bucks with model-predicted winter ranges to test the model 7. Assess how these variables might vary between years and understand why they might have varied. 8. Understand how this knowledge could influence deer management and generate practical recommendations for managing deer harvests and habitats and designing post-hunt composition surveys. For the 2011/12 project year, the short-term objectives were to: 1. Collar 8-10 mule deer bucks 2. Monitor buck survival and retrieve collars as necessary 1

3. STUDY AREA The project area is situated within the northern St at imc Nation Territory in southwestern British Columbia, and represents portions of Wildlife Management Unit (MU) 3-32.

7 3. STUDY AREA The project area is situated within the northern St at imc Nation Territory in southwestern British Columbia, and represents portions of Wildlife Management Unit (MU) Specifically, the study area is situated in the area immediately north of Carpenter Lake, namely 5 Mile and Marshall Ridges and the southern slopes of the Shulaps Range (Figure 1). This area is prime mule deer winter and spring range. The Central Interior and Southern Chilcotin Ecosections are represented within the project area. Average mean temperatures at Lillooet were -3.6 and 21.4 degrees Celsius for January and July (Environment Canada 2005). The project area is situated within the xeric rain-shadow of the southern coastal mountains of the Cascades Forest District (BCWRP 2004) and as result vegetation tends to be those trees and plants adapted to dry conditions. Predominant forest cover includes interior Douglas-fir (Pseudotsuga menziesii) and Ponderosa pine (Pinus ponderosa) and localized patches of bunchgrass grasslands are interspersed throughout. The area overlaps the BC Hydro Bridge River complex, namely the La Joie and Terzaghi Dams which impound Downton and Carpenter Lakes (BCWRP 2004). FIGURE 1. Map of Bridge River study area in Management Unit Stars represent capture locations for 9 mule deer bucks during spring

8 4. METHODS Buck captures Starting March 2011, buck captures were attempted using modified clover traps (Clover 1956) on deer winter range in the study area. Areas to bait were selected to maximize presence of bucks (e.g., higher elevation, rugged terrain, presence of cover). Deer were baited to these sites using alfalfa, apples and minerals. Trail cameras were setup at bait sites to confirm the presence of bucks. Twelve to fourteen sites were baited for 7-10 days and traps were erected at 6 sites bucks were observed utilizing. In total, traps were set for a total of 31 days for a total clover trapping effort of 186 trap days. During April and early May, when deer were congregating on lower elevation spring ranges, bucks were captured by ground-based chemical immobilization with XZT (i.e., Telazol/Xylazine cocktail). Drugs were administered via darts fired from a specialized rifle. Xylazine was reversed with Tolazoline 30 minutes after induction occurred. Biologists stayed with immobilized deer until deer were mobile to monitor recovery and ensure recovery occurred. Captured bucks were fitted with Advanced Telemetry Systems (ATS) G2000 GPS collars. Collars had specialized expandable/retractable inserts, manufactured by ATS, so they could expand when bucks necks swelled during the fall rut and retract again afterwards. Collars were programmed to collect location data for approximately 12 months. To meet objectives, collars were programmed to collect locations every 3 ½ hours from January 1 April 30, when deer are on winter and spring ranges, and July 1 to August 31, when deer are on summer ranges and every 45 minutes May 1 June 30, when deer are migrating to summer range and September 16 to December 31 when deer are migrating back to winter range and are on fall and early winter ranges. Monitoring From the time of capture until deer were on summer ranges in early June, deer were ground monitored, where possible, for survival on a weekly basis using ground-based radio-telemetry techniques. Four helicopter monitoring flights (August 17, December 21, January 6 & March 21) were also undertaken to assess survival status and approximate distribution and to retrieve dysfunctional collars and/or collars from mortalities. Because the collars used stored location data onboard, very little effort was made to pinpoint buck locations during monitoring flights, unless necessary, as the cost didn t justify collection of that data point. 5. RESULTS Buck captures In total, 9 bucks were captured and collared in the study area (Figure 1; Table 1). Three deer, all females, were captured and released during clover trapping. One buck was captured in a clover trap but managed to escape due to trap failure. In the end, all 9 bucks were caught by free range darting. In all cases, induction occurred in under 10 minutes ( 5.5 min.) and recoveries were mostly smooth and normal. 3

9 TABLE 1. Statistics for mule deer bucks captured in the study area spring Bolding indicates that a mortality or disfunctional collar occurred and the collar has been retrieved. Species Capture Est. Weight Est. Age Collar Date (lbs.) (yrs.) Frequency Capture Location Mule deer April W. of Sebring Creek Mule deer April Mile Ridge Mule deer April Viera Creek Mule deer April Mile Ridge Mule deer April Mile Ridge Mule deer April Tyaughton Lake Mule deer April Sebring Creek Mule deer April Marshall Ridge Mule x Black-tailed deer May Slim Creek Monitoring At the time of this report, 3 collars have been retrieved. Two collared bucks ( & ) were legally harvested by resident hunters in the Mowson Pond and 5 Mile Ridge areas in October and November One buck ( ) was apparently harvested between January and March following the regular hunting season. Technical collar issues (likely due to their age) with a couple of the remaining collars ( & ) resulted in those collars transmitting mortality signals when the deer were actually still alive. Because battery life is significantly reduced when sending mortality signals, two collars needed to be prematurely blown-off but have not yet been recovered given difficult access to the area. One other collar on a live buck ( ) recently started sending mortality signals but to maximize data collection, this collar has not yet been blown-off or retrieved. Although buck locations were not accurately collected during monitoring flights, approximate locations were noted. The general pattern of migration to summer range appeared to be west with many bucks summering in the vicinity of Goldbridge and the lower reaches of several drainages in the area. One buck apparently migrated north and summered in the Shulaps Range. Another buck ( ) moved south and summered in the alpine near McGillvray Pass. Most bucks that survived generally returned to winter in higher elevation habitats above their capture locations. Data from collars is needed to confirm these general observations. 6. DISCUSSION Buck captures Overall, buck captures went extremely well using ground-based chemical immobilization techniques. In contrast, buck captures using clover traps were difficult and labor intensive for a couple of reasons. First, March is generally too late in the winter to begin baiting and capturing deer using traps as preferred natural forage becomes available with the onset of spring. A December start would increase success but funding cycles did not correspond with an earlier start. Secondly, the study area and trap sites were remote and required snowmobile access and it proved to be labor intensive and costly just to check traps on a daily basis. Thirdly, selective study animals were required (i.e., spatially distributed bucks across age classes) and given the low capture rate experienced it was not practical to be selective. 4

10 7. RECOMMENDATIONS The following are recommendations arising from the project to date: 1. Free range darting should be used for future captures. It is the most efficient method of capturing deer in this study area, especially when selective and spatially distributed study animals are required. 2. New collars should be purchased to continue the project in the future to maximize data collected from study animals. 8. ACKNOWLEDGEMENTS We d like to thank the Fish & Wildlife Compensation Program for providing financial support to initiate and continue this project. Thanks to Bob Butcher, Gilbert Redan, Gerry Kuzyk, Kevin VanDamme, Mike Burwash, Tim Cody and Matt Manual for assisting with capturing, collaring and monitoring bucks. Thanks also to CC Helicopters for providing safe helicopter services. 5

11 9. REFERENCES Bridge Coastal Fish and Wildlife Restoration Program Strategic Plans. Volume. 2. Available: Accessed September 24, Brown, C.G Movement and migration patterns of mule deer in southeastern Idaho. Journal of Wildlife Management 56: Clover, M.R Single-gate deer trap. California Department of Fish and Game Bulletin 42: Environment Canada Canadian climate normals Environment Canada, Ottawa, Ont. Hatter, I.D. Low, B. Lincoln and D.Janz Deer Management Plan for British Columbia BC Fish and Wildlife Branch, Ministry of Environment, Victoria, BC. Kie, J.G., R. T. Bowyer, M.C. Nicholson, B.B. Boroski, and E.R. Loft Landscape heterogeneity at different scales: effects on spatial distribution of mule deer. Ecology 83: Poole, K. and K. Wright Mule Deer Migration and Seasonal Ranges within the St at mic Nation Territory, southwestern British Columbia. Prepared for the Lillooet Tribal Association. 35pp Sawyer, H., M.J. Kauffman and R.M. Nielson Influence of Well Pad Activity on Winter Habitat Selection Patterns of Mule Deer. Journal of Wildlife Management 73: Walter et al Regional assessment on influence of landscape configuration and connectivity on range size of white-tailed deer. Landscape Ecology 24:10,

12 10. APPENDIX 1. Financial Statement INCOME BUDGET ACTUAL FWCP Other FWCP Other Total Income by Source 38, , , , Grand Total Income (FWCP + other) 119, , EXPENSES Project Personnel St at imc Technician 9, , Contract Biologist 1, MOE Biologists 25, , St at imc NRO 2, , Materials & Equipment Equipment Rental/In-kind 12, , , , Materials Purchased 4, , , , Equipment maintenance 8, , Travel cost-fuel Vehicle Rental/Mileage Food/Per Diem/Accomodation 3, , Administration Office Supplies Photocopies & printing Postage/customs fees Computer costs Communications Total Expenses 38, , , , Grand Total Expenses (FWCP + other) BALANCE (Grand Total Income Grand Total Expenses) 119, , The actual balance might not equal $0* 2,

Mule Deer Buck Migrations and Habitat Use in the Bridge River, British Columbia: Preliminary Results (FWCP Project # 12.W.BRG.03)

Mule Deer Buck Migrations and Habitat Use in the Bridge River, British Columbia: Preliminary Results (FWCP Project # 12.W.BRG.03) PREPARED BY: Chris Procter, R.P.Bio Francis Iredale, R.P.Bio Ministry of