Aerial Classified Mountain Goat and Bighorn Sheep Count, Penticton Creek to Vaseux Creek, South Okanagan, March 2009.

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1 Aerial Classified Mountain Goat and Bighorn Sheep Count, Penticton Creek to Vaseux Creek, South Okanagan, March Prepared by: Les W. Gyug, R.P. Bio., Okanagan Wildlife Consulting, 3130 Ensign Way, Westbank, BC V4T 1T9 Prepared for: Weyerhaeuser Co. Ltd. P.O. Box 550, Old Hedley Road, Princeton, B.C. V0X 1W0 Submitted: March 21, Introduction and Methods Okanagan Wildlife Consulting was contracted by Weyerhaeuser Co. Ltd. with funding from the Forest Investment Account to conduct an aerial classified count of the bighorn sheep and mountain goat populations on the east side of Okanagan Lake from Penticton Creek to Vaseux Creek in Management Units 8-01 and 8-09 in March, 2009 (Figures 1-2). The survey method was an encounter transect (RISC 2002) with classification of all mountain goats as juveniles (kids), yearlings, and adults, and classification of bighorn sheep as juveniles (lambs), adult ewes (including yearlings of both sexes, and possibly some 2-year old rams) and adult rams (Classes I, II, III and IV). The flight was conducted using 6.0 hours of flying time on March 19, 2009, in a Bell Jet Ranger helicopter provided by Canadian Helicopters of Penticton piloted by Ted Fisher. The navigator and recorder (LG) sat in the front seat of the helicopter while two observers (Brian Harris of Ministry of Environment, and volunteer Brent Ryll) were in the back seat of the helicopter assisting in locating, counting and classifying ungulates. All other ungulates seen were recorded, but not necessarily classified to age or sex. Each observation was GPS marked, but the location of the helicopter when the GPS was marked was not necessarily right over the animal, so the accuracy of the observations should be considered to be within 200 m. All data was entered into the Ministry of Environment, Wildlife Species Inventory, Ungulate Aerial Observation Excel template, which was submitted electronically along with this report. Survey areas were covered by parallel flight paths about 300 m apart (Figure 1). Total survey area was 77 km 2 in MU 8-09 from Penticton Creek to Shuttleworth Creek, and 31 km 2 in MU 8-01 from Shuttleworth Creek to Vaseux Creek. Average search effort was about 19 km 2 /hour, or about 3 min/km 2. Additional bighorn sheep were known to occur south of Vaseux Creek, and additional mountain goats known to occur in Inkaneep Creek, but time constraints did not permit these areas to be surveyed. The results from the March, 2009, survey were compared to prior survey results from the Okanagan Region ungulate aerial survey database maintained by the Ministry of Environment. Results A total of 205 bighorn sheep (Table 1, Fig. 1) and 35 mountain goats (Table 2, Fig. 2) were observed. We also observed 2 moose (cow and calf on the south side of Ellis Creek), 219 mule deer scattered throughout the survey area, 6 while-tailed deer in the Shuttleworth Creek area, and a single herd of 25 elk including about 20 antlered bulls of all ages north of Penticton Creek (Fig. 2).

2 Table 1. Bighorn sheep observed, and numbers in each age and sex class on aerial survey of March 19, 2009, in the south Okanagan from Penticton to Vaseux Creek. Rams Location Total Lambs Ewes 1-2 yr old Cl I Cl II Cl III Cl IV Penticton Creek-Steward Creek Ellis Creek-Fairview Bluffs S of Gillies Creek MacLean Creek-Peach Bluffs Shuttleworth to Vaseux Creeks Upper Vaseux Creek Total Note: Ewe class includes yearlings of either sex. Yearling and 2-year old males may have been classified as ewes or young rams depending on how well the group was observed. Class III rams were not all >3/4 curl as per RIC manual standards, and included rams that were just at the 3/4 curl mark. Table 2. Aerial classified mountain goat count results in Penticton Creek, Ellis Creek and Shuttleworth Creek in March, 2009, compared to previous counts. Note that 2 yearlings were included in the 16 adults seen at Penticton Creek in Location Dates Total Count Adults Kids No. of Groups Seen Penticton Cr. 19-Mar Ellis Cr. 19-Mar Shuttleworth Cr. 19-Mar Prior Surveys Penticton Cr Oct Nov Jan Mar Mar Mar Nov Nov Ellis Cr Mar Mar Nov Nov Shuttleworth Cr. Oct Mar

3 Bighorn Sheep The 205 bighorn sheep counted during the March, 2009, survey was a much higher count than the 126 counted in the same survey area in March, 2003, (Table 3). The herd appears to have at least partly recovered from the disease outbreaks that significantly reduced herd numbers around Sightability has been estimated at about 70% (Gyug 2003) and 76% (Chapman 1999) for this herd in spring helicopter surveys. Four radio-collared sheep (two rams and two ewes) were sighted, but the radio telemetry project had finished so we did not know how many collars were available for sighting at the time of our survey. At least one band of about 20 at Penticton Creek (Mark Hubbard, pers. comm.) was not sighted on the count. The previous sightability estimates of 70-75% probably applied to the 2009 count as well. Therefore overall herd size north of Vaseux Creek in spring of 2009 was probably in the range of sheep. This estimate did not include any sheep that may have been south of Vaseux Creek. Size of the band south of Vaseux Creek near Mud Lake was estimated at 20 in 2003 (John Kruger, pers. comm. 2003) and had been as high as 60 in 1991, although it was generally in the range of in most years (Table 3). As of late winter 2009, sheep numbers in the Mud Lake area south of Vaseux Creek may be in the range of 20-25, and further south by Osoyoos may be in the range of or slightly more (Jim Weins, pers. comm..). Therefore the size of the sheep population east of Okanagan Lake and from Penticton Creek south is probably in the range of , and may be only slightly below the estimate of about 430 made in the late 1990 s (Chapman 1999). Considering only those counts that classified nearly 100% of the sheep observed, the ratio of lambs to 100 ewes was 20 in 1998, 48 in 1999, 23 in 2003, and 35 in The ratio of rams per 100 ewes was only 33 in 1998, but was much higher at 55 in 2003 and 50 in This only included ram ratios from counts when surveys of all habitats were completed. The ratio was usually much lower when only partial counts were done because rams tended to be found in small isolated groups, and partial counts tended to be done where the maximum number of sheep could be counted in the minimum amount of time, which meant survey effort was concentrated in the areas where ewe-lamb herds were known to occur. Unbiased ratios of rams to ewes can only be estimated from complete area surveys, or from counts done during the rut when both ewes and rams are found on the same ranges. Mountain Goats The size of the Penticton and Ellis Creek mountain goat herd appears to have stabilized at about 30 (range of from ; Table 2) considering only the highest of the counts (i.e. excluding March and November 2005 when very few goats were seen in Ellis Creek). The percentage of kids in the herd has been quite consistent at 17-22% during that period. The herd appeared to peak in size in (Table 2) after the Penticton Creek fire of 1971 probably opened additional range to the herd, but which has since reforested and is no longer suitable (Gyug 2006). No more than 4 goats have ever been observed in Shuttleworth Creek on any survey, but additional goats to the 4 observed in March, 2009, may have been present. The 4 goats were observed on the north side of the canyon but additional goat tracks were seen 3.4 km downstream on the south side of the canyon where some goats were seen by the helicopter pilot on a training flight about one month earlier.

4 Table 3. Comparison of 2009 bighorn sheep counts to prior counts in the south Okanagan. North of Vaseux Cr. South of Vaseux Cr. Date Total Total Total 19-Mar Mar Mar Mar Jan-Feb Mar Jun Jun Notes: 2009 did not cover S of Vaseux Cr 2003 did not cover Long Joe (Osoyoos) but did cover Mud Lake south of Vaseux Cr 1998 data was not separated by area or individual locations Literature Cited Chapman, T.E South Okanagan valley California bighorn sheep habitat inventory: Final report B.C. Environment, Okanagan sub-region, Penticton, B.C. Gyug, L.W Ungulate Aerial Surveys, Okanagan Region, February-March Okanagan Region, B.C. Ministry of Water, Land and Air Protection, Penticton, B.C. Gyug, L.W Mountain goat population and harvest assessment in the Okanagan Region. B.C. Ministry of Environment, Penticton, BC. Resources Inventory Standards Committee (RISC) 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. Ministry of Environment, Victoria, B.C.

5 %U Penticton Fairview S S S S Penticton Cr. Steward Cr. S S Ellis Cr. Sheep Group Size S 1-2 S 3-6 S 7-10 S S Survey Track S SS S S Gillies Cr. S S 8-9 OK Falls %U S S S S S S MacLean Cr. S Shuttleworth Cr. S N Kilometers S SS S S S SS S S S S S S 8-1 S Vaseux Cr. Figure 1. Locations of bighorn sheep observed during aerial classification survey of the area from Penticton Creek to Vaseux Creek on the east side of the Okanagan valley, 19 March 2009.

6 %U Penticton Fairview S $T Y Y Y Y Y Y Y Penticton Cr. Steward Cr. Ellis Cr. Survey Results Y Mt. Goat $T Moose Mule Deer S White-tailed Deer S Elk Survey Track S Gillies Cr. 8-9 MacLean Cr. OK Falls N %U Y S Y S Shuttleworth Cr. Tracks Only Kilometers Vaseux Cr. Figure 2. Locations of mountain goats and other ungulates observed during aerial survey of the east side of Okanagan valley from Penticton Creek to Vaseux Creek, 19 March 2009.