An overwhelming response to a request for volunteers lead the Tranquille sheep transplant to be a great success. The Wild Sheep Society would like to thank all the volunteers who came out from the Kamloops fish and game club, the Wild Sheep Society, ministry staff, and local first nation groups. As well as others as there was close to 100 people in attendance.

It was great to see the level of commitment many outdoorsman have, this resulted in some volunteers not being able to participate as the provincial wildlife veterinarian felt that the more noise and people around the sheep would only increase the stress levels of the animals.

To give some background of the transplant the tranquille area has close to 150 sheep in it. There were approximately 75 at the bait at one point and up to 50 rams were spotted along the road to the bait. These rams never came to the bait. Poles and guy ropes were set up on Dec 20 and placed out with bait. Once again we would like to thank the volunteers that came out in near -20 temps to help put up the poles. It’s always easy getting help for the actual sheep work and a little tougher for the other stuff. Thanks again. Wild Sheep Society of BC

Bighorn Sheep Transplant Report
to Okanagan Mountain Provincial Park: prepared By Brian Harris
January 2009

On January 17, 2009, 15 California bighorn sheep were captured near Kamloops B.C. and transported 200km to Okanagan Mountain Provincial Park, on the east side of Okanagan Lake between Kelowna and Penticton. This release will augment the bighorn population already in the Park.

Background
California bighorn sheep are native to the Okanagan Valley and once roamed from the US border to north of Kelowna (Shackleton, 1999). However, more than a century of challenges and habitat changes including fire suppression, human development, agriculture, range loss, disease, over-hunting and competition with domestic livestock had reduced the bighorn range to a narrow band of low elevation land primarily on the east side of the Valley south of Penticton. In 1999 the south Okanagan bighorns numbered at least 450. However, during the winter of 1999/2000, a pneumonia epidemic killed about 70% of these animals. The Recovery Plan recommended expanding the bighorn range in the Okanagan by establishing healthy new sub-populations in suitable but unoccupied habitat (Harper 2002). Okanagan Mountain Provincial Park was one potential area that was made suitable for bighorns by the fire of 2003. In January 2007, 34 bighorns were captured by drop net near Keremeos, B.C. and released near Wildhorse Canyon in Okanagan Mountain Provincial Park (Harris 2007). An inventory flight in November 2008 counted 40 bighorns in the Park.

Okanagan Mountain Provincial Park (OMPP) is 10,000 ha of rugged, rocky grassland and dry forest on the east side of the Okanagan Valley between Kelowna and Penticton. The elevation ranges from 325m at the lakeshore to the 1572m peak of Okanagan Mountain. Until the transplant of 2007, bighorns were only casual visitors to OMPP. The most likely reason for this lack of persistence was the habitat condition. Historically, the normal fire return interval for the low elevations of the Okanagan was less than 35 years (Blackwell 2003) perhaps as frequent as 5-7 years. However, following nearly a century of fire suppression, dense stands of Douglas fir and yellow pine had invaded the rocky hillsides, grasslands and open forest preferred by bighorns, making the habitat basically unsuitable. That situation changed with the wildfire of 2003. Many of the encroaching trees, especially in dense and stunted stands, were killed. The most common surviving trees were the veteran Douglas fir and yellow pine with thick, corky bark which are now widely spaced with vigorous grasses and shrubs between. A habitat capability study found that conservatively the Park could support at least 90 bighorns (Wood and Haney, 2005).

Source Population
The bighorns at Tranquille, about 10km east of Kamloops, had increased to the point that MOE biologists in Kamloops had concerns about disease due to crowding and habitat overuse. The goal was to reduce that population by about 50 animals (D. Jury, pers.com) and suitable release sites were needed.

Release Site
Habitat mapping (Wood and Haney 2005) showed the south-western corner of OMPP to have both high capability winter forage and escape terrain. Access to this habitat involved crossing Mission Hill Naramata Ranch Vineyard north of Naramata, B.C.

Capture
Every morning for several weeks, the bighorns were enticed to the selected trap location with a bait of rich alfalfa hay and apple pulp. Once a pattern was established, the drop net was installed. This is a 20mX20m square net with a 10cm mesh of heavy nylon cord suspended at the four corners on 6.5m tall poles. The suspension system includes electrically operated switches that, when activated, release the net to drop on the unsuspecting animals at the bait.

All volunteers were assigned specific tasks and received instruction on stabilizing and moving the captured animals. Once entangled in the net, each bighorn was blindfolded to cover and protect their eyes and calm the animal and their legs bound with leather hobbles. The restrained bighorns were carried to a processing area for samples of blood, hair and feces and medications. All bighorns were ear tagged and some were fitted with a radio transmitting collar. Once processed, the animals were freed of the hobbles and blindfolds and placed in two modified horse trailers.

Release
The 2.5m high page wire fence separating the Mission Hill vineyard from OMPP was cut and opened so that the horse trailers could be maneuvered into position. Snow fencing created a chute from the rear of the trailer, through the fence and into the Park. When the sliding door of the trailer was opened the bighorns ran up the hill to their new home.

Results
We moved 15 animals, 10 adult ewes, 4 ewe lambs and 1 ram lamb (see details in appendix). Lab tests verified that all 10 ewes are pregnant.

Participants
There were at least 70 people involved at the capture, including representatives from Wild Sheep Society of BC, BC Wildlife Federation, Kamloops Fish and Game Association, Ministry of Environment, Conservation Officer Service, Kamloops Indian Band and students from Nicola Valley Institute of Technology and Thompson Rivers University, Animal Health Technology.

Media coverage in the Okanagan included: local newspapers (Kelowna Capital News, Penticton Herald, Okanagan Sunday, Penticton Western News) and CHBC TV.

The project was funded primarily by the Wild Sheep Society of BC.

Habitat Management
A management goal of BC Parks for Okanagan Mountain Provincial Park is the re-introduction of fire into fire maintained ecosystems and 20 potential burn sites have been identified (Gebauer, 2001). Following the wildfire of 2003 and the approval to transplant the bighorn sheep, a habitat maintenance plan was developed to prioritize the identified burn sites for their value to bighorns (Wood, 2006). Reburning some selected sites is scheduled to begin in 2009 in order to maintain habitat condition and remove conifer seedlings.

Harvest Management
Management Unit 8-09, which includes Okanagan Mountain Provincial Park is divided into zones A and B for bighorn hunting. A hunting moratorium is in place for Zone B, which includes the area of this transplant, so that bighorn hunting can continue in the remainder of the Management Unit while the transplanted animals get established in their new range.

Literature cited

Blackwell, B.A. (2003). Developing a Coarse Scale Approach to the Assessment of Forest Fuel Condition in Southern B.C. Forest Investment Initiative Report R2003-0112. Pacific Forestry Centre, Victoria, B.C.
Gebauer, Martin (2001) Candidate Prescribed Burning Sites in Okanagan Mountain Provincial Park. Report for BC Parks, Okanagan District, Summerland, B.C.
Harper, W.L., T.J. Ethier, H.M. Schwantje and I. Hatter. (2002). Recovery Plan for California Bighorn Sheep in the South Okanagan Valley, British Columbia. Unpublished report. Ministry of Environment, Lands and Parks, Victoria, BC.
Harris, B. (2007). Okanagan Mountain Park Bighorn Transplant Report. Unpublished report for Ministry of Environment, Penticton, B.C.
Shackleton, D. (1999). Hoofed Mammals of B.C. Royal British Columbia Museum Handbook, Volume 3. UBC Press, Vancouver, B.C. ISBN 0-7748-0728-8.
Wood, C. and A. Haney. (2005) Okanagan Mountain Park California Bighorn Sheep Transplant: A Review of Available Habitat Based on Updated Suitability Modeling. Unpublished report for BC Environment, Penticton B.C.
Wood, S., Stepaniuk, D., and Wood, C., (2006). Okanagan Mountain Park Habitat Maintenance Plan. Unpublished report for B.C. Ministry of Environment, Penticton, B.C.

Appendix

SEX AGE WEIGHT(approx) EAR TAG COLLAR Pregnant?
F LAMB 65 lbs 17 (right) none N
F 5 100+ lbs 10 (right) 151.010 Y
F 4 100 lbs 28 (right) none Y
F 4 16 (left) none Y
F 8+ 100+ lbs 8 (left) 151.480 Y
F 7 12 (right) 151.470 Y
M LAMB 31 (right) none N
F 3 80 lbs 20 150.325 Y
F 2 80+ lbs 18 (left) none Y
F 5 3 (left) none Y
F LAMB 60 lbs 15 (right) none N
F 6+ 100+ lbs 14 151.380 Y
F LAMB 27 (right) none N
F LAMB 50 lbs 19 (left) none N
F 6 100+ lbs 9 (right) 150.701 Y

Around Jan. 5 the net was strung above the bait. This is always a stressful time as you don’t know how the sheep will react. In this instance they were almost pushing us out of the area trying to come into the bait.

With the warmer weather we have had, some of the sheep had wandered off but we still had close to 40 animals coming in daily so we knew we would get a good catch. All week before the big drop we were getting close to the 40 sheep coming in like clockwork. On Thursday the bio went out to bait and there were no sheep in area, they vanished. He went for a hike to see if he could find them and no luck. On his way back there was 3 sheep on the bait and that’s it. No sheep the day before the transplant. It was a stressful night that night as we had close to 80 volunteers lined up for the morning and the possibility of no sheep.

Morning arrived and there was sheep in the area. Things went pretty good. There was close to 30 under the net when the release was hit but a corner of the net did not release so about 8 animals got out. Even with that 20 sheep were captured and thanks to those who volunteered were within the hour headed to their new home.

After the sheep were on there way, the net was strung up again and there were once again about 8-10 sheep waiting for us to clear to get to the bait.

Saturday morning we had just as many volunteers and the net dropped on 15 sheep. These sheep were also quickly processed and headed for Okanagan Mountain Park.

So 35 sheep have new homes and there were no major injuries so it was a great weekend. Thanks again to all those who volunteered.