Mountain goat survey in the Shulaps Range, subzone 3-32C, Thompson region, British Columbia, July 2007

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Thompson Region 1259 Dalhousie Drive Kamloops, BC V2C 5Z5 Prepared by: Kim G.

1 Shulaps Range Mountain goat survey in the Shulaps Range, subzone 3-32C, Thompson region, British Columbia, July 2007 Prepared for: Doug Jury British Columbia Ministry of Environment Thompson Region 1259 Dalhousie Drive Kamloops, BC V2C 5Z5 Prepared by: Kim G. Poole 2305 Annable Road, Nelson BC V1L 6K4 Tele. (250) ; September 2007

2 ii ABSTRACT Mountain goats (Oreamnos americanus) are managed as a big game species in British Columbia, and as such, aerial surveys are conducted periodically to document population trend and productivity, and to establish hunting quotas. As a result of low hunter resident success and suspected declines in the population, a survey was conducted to determine the numbers and distribution of goats in subzone 3-32C in the Shulaps Range of the Chilcotin Ranges west of Lillooet in late July Standard survey techniques were followed using a Bell 206B helicopter. We used 5.0 hrs of helicopter time, including 4.2 hrs on survey, and surveyed a km 2 census zone of potential goat habitat under good survey conditions. Overall survey effort averaged 1.4 min/km 2. We observed 1 group of 10 goats (6 adults, 4 kids) in the headwaters of Bighorn Creek at 7,100 feet (2,170 m) elevation. A sightability correction was difficult to apply, but I suggest that the subzone s goat population numbers <30 40 animals, and may be as low as 20 goats. Five groups of California bighorn sheep (Ovis canadensis californiana) totalling 34 animals were also observed (primarily ewes and young rams, with 2 lambs). The last complete summer survey within the subzone was conducted in 1991, when 69 goats were counted. The survey in 2007 covered almost all areas where goats have been observed in previous years, including the historic core area of use. It appears unlikely that we missed significant numbers of goats within the census zone. These results suggest that the population has declined considerably in the past 15 years. The causes of this decline are unknown; approximately animals were harvested in the subzone between 1988 and 2005, the bulk of them during the 1990s. Predation and disease may also factor in the decline. Based on the low numbers of goats estimated for the area, I suggest that hunting be eliminated until such point as the population is shown to be larger. Should funding and priorities permit, I suggest resurveying the subzone in 1 2 years to verify or refute the results we observed.

3 iii TABLE OF CONTENTS ABSTRACT...ii INTRODUCTION...1 STUDY AREA...1 STUDY DESIGN AND METHODOLOGY...2 RESULTS...2 DISCUSSION...4 Population estimate...4 Management recommendations...4 ACKNOWLEDGEMENTS...5 LITERATURE CITED...5

4 1 INTRODUCTION Mountain goats (Oreamnos americanus) are a high profile species in British Columbia, valued by hunters and non-hunter alike. Mountain goats are widespread in eastern and western sections of the Thompson Region (Region 3) of southern British Columbia (Shackleton 1999), with roughly 6% of the provincial total (Hatter 2005b). All goat hunting within the region is controlled on a permit system, based on estimated population size, with approximately 220 resident goat permits and 17 non-resident permits allocated annually. There is a perception of population declines across much of the region (Lemke 2005, D. Jury, Ministry of Environment [MoE], Kamloops, pers. comm.), but limited surveys have been conducted from the late 1980s to mid 2000s to substantiate this trend (Poole 2007a). Periodic surveys are required to update population estimates to ensure that harvests are sustainable. This survey focussed on subzone 3-32C in the Shulaps Range west of Lillooet and north of Carpenter Lake (Fig. 1). The impetus for the survey was very low resident harvest success and a suspicion that goat numbers were reduced in the area (D. Jury, MoE, Kamloops, pers. comm.). Survey data from this subzone are sparse. In a mid-august 1991 survey, 69 goats in 4 groups were observed within the subzone (MoE, Victoria, unpublished data). Five goats were observed during a reconnaissance flight for wildfires in early August 2000, and 13 goats were observed during a late February 2003 winter range survey (D. Jury, MoE, Kamloops, pers. comm.). Although 10 resident Limited Entry Hunting (LEH) permits are allocated annually within the subzone and resident interest for permits appears high (~7:1 first choice odds in recent years), only 1 goat was reported killed by residents from 1999 to 2005 (compulsory inspection reports, MoE, Victoria). Resident hunter effort within the subzone (i.e., whether a permitted hunter actually hunts) is unknown. Three non-resident permits are allocated to the one guide outfitter assigned the subzone for the current 5-year period (0.6 permits/year). The objectives of this survey were to determine the number and distribution of mountain goats within the subzone, and to compare survey results with historic data. Data obtained will be used to support current harvest management strategies. STUDY AREA The Shulaps study area is located in the Chilcotin Ranges of the Coast Mountains, in the dry climatic moisture regime of the (former) Kamloops Forest Region (Lloyd et al. 1990). Potential goat habitat in the study area primarily is made up of 2 biogeoclimatic zones: the Engelmann Spruce- Subalpine Fir (ESSF) zone and the Alpine Tundra (AT) zone above tree line. Tree line is generally located between 1,800 2,000 m (5,900 6,550 ft) (Lloyd et al. 1990). July and January mean temperatures for Lillooet, 20 km southeast of the study area, are 21.4ºC and 3.6ºC, respectively (Environment Canada climate normals, unpublished data). Lillooet receives an average of 330 mm of precipitation including 32 cm of snowfall annually. Climate varies within the study area, with cooler temperatures and deeper snowfalls at higher elevations and on north and east-facing slopes. High on the valley sides, hybrid white-engelmann spruce (Picea glauca x engelmannii) and subalpine fir (Abies lasiocarpa) dominate, with scattered stands of lodgepole pine (Pinus contorta) on drier sites (Lloyd et al. 1990, Parish et al. 1996). In the AT zone, conifers are present only in stunted krummholz forms. A census zone of potential goat habitat was surveyed, which generally included steep or cliff habitat above 6,000 6,500 feet (1,850 2,000 m) elevation and below tree line down to about 5,500 feet (1,675 m). (Feet are included as the unit of measure because the helicopter s altimeter was in feet).

5 2 STUDY DESIGN AND METHODOLOGY Study design and methodology generally followed RISC standards (RISC 2002, Poole 2007b), and consisted of a total count survey, with sightability correction subjectively applied afterwards. The study area was comparatively small, and thus the area was not divided into blocks. We began our survey at first light (5:55 am) and finished prior to noon. We used a Bell 206B Jet Ranger helicopter with pilot, navigator, and 2 observers. The helicopter was equipped with bubble windows in the rear, and wedge windows in the front. All occupants participated in locating mountain goats, and all had extensive experience at aerial surveys. We surveyed all alpine and open subalpine habitat, as well as areas of broken or disjointed cliffs and avalanche chutes below tree line down to about 6,000 feet. Some lower elevation slopes were also surveyed. We flew roughly m ( foot) contour lines at km/hr, m out from the hillsides. We rarely used >10 minutes between adjacent contour flights to minimize the potential for excessive vertical movements of goats between passes. We mapped approximate flight lines and survey coverage on 1:50,000 scale topographical maps and calculated the census zone based on the area surveyed. We also recorded broad habitat type, and elevation from the helicopter s altimeter (estimated to the nearest 100 feet). Goat locations and helicopter flight tracks were recorded with a hand-held global positioning system (GPS) unit, which was later downloaded to a computer. We classified goats only into kids and non-kid (yearlings and older; hereafter called adults) based on body size (Smith 1988) to reduce survey time, to minimize harassment (Côté 1996), and because researchers familiar with classification from aircraft agree more detailed age and sex classification is not reliable (Houston et al. 1986, Stevens and Houston 1989, Gonzalez-Voyer et al. 2001, S. Côté, Université de Sherbrooke, personal communication). Incidental wildlife sightings were also recorded. RESULTS We censused subzone 3-32C on 25 July Survey conditions and lighting were generally good with clear skies and calm winds. Temperatures within the census zone ranged from 4 8ºC at survey time. We used 5.0 hrs of helicopter time, including 4.2 hrs on survey, and surveyed a census zone of km 2. Survey intensity averaged 1.4 min/km 2. We observed 10 goats (6 adults, 4 kids) in 1 group in the Bighorn Creek drainage (Fig. 1), for an average observed density of 0.05 goats/km 2. Given the single goat group observed it is difficult to apply a sightability correction to this survey (Poole 2007b). Conservatively, I would guess that the subzone has <30 40 goats present, possibly as low as 20 animals. The goat group was observed at 7,100 feet (2,170 m) elevation in an area of broken cliffs several hundred metres below a ridgeline. The only other wildlife observed during the survey was 34 California bighorn sheep (Ovis canadensis californiana) in 5 groups (Fig. 1). Only 2 lambs were seen among the ewes and young rams observed. Sheep groups occurred at 7,200 8,000 feet (2,200 2,450 m) elevation.

6 Figure 1. Location and number of mountain goats and California bighorn sheep observed during the survey of subzone 3-32C, 25 July The orange polygon approximates the census zone, which covers potential goat habitat. 3

7 4 DISCUSSION Population estimate Weather conditions during the survey were close to ideal. Hot weather earlier in July had been followed by a period of cooler and wetter weather, which had ended a couple of days prior to the survey Thus, we did not suspect that goats were hiding within treed areas in reaction to hot weather. Survey effort was similar to effort used for goat surveys in the Kootenay Region (Poole 2007b) and a recent survey in the North Thompson (Poole 2006), and the open habitat at higher elevations facilitated effective scans of the census zone. Although it is almost certain that we missed some animals, it is unlikely that we failed to detect a substantial number of goats within the census zone. With the exception of a single goat observed in August 2000, our survey coverage corresponded with all areas where goats have been sighted on past summer surveys. The goat group observed was centred in the area where historic survey data indicated the greatest number of animals have been present, the mountains between Jones, Bighorn, and Fall creeks to the south and Shulaps and Holbrook creeks to the north. Our survey effort was greatest within this area. Few tracks were observed during the survey, but where fresh tracks were observed on scree or on rare snow patches, they were invariably associated with bighorn sheep. Given the single goat group seen, it is difficult to reliably assign an estimate to the survey. I suspect that at the most fewer than goats may occur within the area, and the number may be as low as 20 animals. However, given the small number of goat groups likely present within the study area, missing 2 3 groups could have a substantial impact on the estimate for the area. Although we have no indication that this occurred, if significant numbers of goats were located outside of our census zone but within the subzone, then our estimate for the subzone will be biased low. No complete survey of the subzone has been conducted since 1991, when 69 goats were counted (group sizes were 1, 13, 22, and 33). Thirteen animals were observed during February 2002 winter range surveys, consistent with numbers observed during the current survey. It appears highly likely that the goat population within the subzone has declined substantially over the past decade and a half. Causes for this decline are unknown. According to compulsory inspection data, goats were harvested in the subzone between 1982 and 2005 (~1.0/yr; 4 F, 8 9 M), with 11 animals taken between 1990 and (Compulsory inspection data are difficult to reliably quantify at the subzone level because of management unit/subzone label and location issues; thus the uncertainty in the total number of goats harvested within 3-32C). Resident hunters took all but 1 2 of the goats harvested. Harvesting at this rate may have contributed to the decline, although predation and disease could have also played a factor. Although a small sample, the 4 kids in the group of 10 animals suggest that kid production is currently healthy. In summary, based on the observation of 10 goats within the historic summer range, I suggest that the goat population in the subzone numbers fewer than animals. However, based on our observation of only 1 group of goats, I have limited confidence in this estimate. Management recommendations Our survey indicates that the goat population likely numbers fewer than animals within subzone 3-32C. Based on currently Ministry of Environment recommendations on sustainable mountain goat hunting, populations of <50 animals should not be hunted (Hatter 2005a). Until there is evidence that more goats inhabit the subzone, I recommend that all resident and non-resident goat hunting be eliminated. In fairness to resident and non-resident hunters within the subzone, and if funding is available, it may be worthwhile to resurvey the area in 1 2 years to confirm or refute these results. I suggest that the

8 5 local outfitter(s) and knowledgeable residents be interviewed prior to the survey to ensure that all areas where goats are thought to occur are surveyed. Participation in the survey by an interested and experienced local resident or outfitter would enhance the value of the exercise in the eyes of users. ACKNOWLEDGEMENTS This survey was funded by British Columbia Ministry of Environment. S. Taylor, C C Helicopters Ltd., Lillooet, provided expert piloting. D. Jury and B. Butcher, BC Ministry of Environment were observers during the survey, and I thank them for their enthusiasm and assistance. Thanks to D. Jury for the opportunity to conduct this survey. D. Jury provided helpful comments on an earlier version of this report. LITERATURE CITED Côté, S.D Mountain goat responses to helicopter disturbance. Wildlife Society Bulletin 24: Gonzalez-Voyer, A., K.G. Smith, and M. Festa-Bianchet Efficiency of aerial surveys of mountain goats. Wildlife Society Bulletin 29: Hatter, I. 2005a. Guidelines for determining sustainable harvest of mountain goats. Presented at the 1st BC Mountain Goat Workshop, Prince George, BC, March Hatter, I. 2005b. Mountain goat status and inventory needs in British Columbia. Presented at the 1st BC Mountain Goat Workshop, Prince George, BC, March Houston, D.B., B.B. Moorhead, and R.W. Olson An aerial census of mountain goats in the Olympic Mountain Range, Washington. Northwest Scientist 60: Lemke, S Mountain goat population inventory, Thompson region, management units 3-43 and Ursus Ecological Consulting, Kamloops. Unpublished report for British Columbia Ministry of Environment, Kamloops, British Columbia. Lloyd, D., K. Angove, G. Hope, and C. Thompson A guide to site identification and interpretation for the Kamloops Forest Region. British Columbia Ministry of Forests Land Management Handbook no. 23, Victoria, British Columbia. Parish, R., R. Coupé, and D. Lloyd (Editors) Plants of southern interior British Columbia. Lone Pine Publishing, Vancouver, British Columbia. Poole, K.G Mountain goat survey in Management Unit 3-44, Thompson region, British Columbia, September Unpublished report for British Columbia Ministry of Environment, Kamloops, British Columbia. Poole, K.G. 2007a. A population review of mountain goats in the Thompson Region. Unpublished report for British Columbia Ministry of Environment, Kamloops, British Columbia. Poole, K.G. 2007b. Does survey effort influence sightability of mountain goats during aerial surveys? Wildlife Biology 13: RISC (Resources Information Standards Committee) Aerial-based inventory methods for selected ungulates: bison, mountain goat, mountain sheep, moose, elk, deer and caribou. Standards for components of British Columbia s biodiversity No. 32. Version 2.0. Resources Information Standards Committee, B.C. Ministry of Sustainable Resource Management, Victoria, British Columbia.

9 6 Shackleton, D Hoofed mammals of British Columbia. The Mammals of British Columbia, Volume 3, Royal British Columbia Museum. UBC Press, Vancouver, British Columbia. Smith, B.L Criteria for determining age and sex of American mountain goats in the field. Journal of Mammalogy 69: Stevens, V., and D.B. Houston Reliability of age determination of mountain goats. Wildlife Society Bulletin 17:72 74.

Mountain Goat Population Inventory Thompson Region Management Units 3-32 and July 18 20, 2005

Mountain Goat Population Inventory Thompson Region Management Units 3-32 and 3-33 July 18 2, 25 Prepared for: British Columbia Conservation Foundation Prepared by: S. L. Lemke, R.P. Bio. October 25 SUMMARY