Research News To The Members of The West-Central Alberta Caribou Standing Committee
Issue 5, May 2002
© University of Alberta
West-Central Alberta Caribou Standing Committee Research Subcommittee
Woodland Caribou Recruitment in West-Central Alberta – How and Why is it Measured?
By Jeff Kneteman, Research Subcommittee Chair
By Kirby Smith, Area Wildlife Biologist, Alberta Fish and Wildlife Division, Edson
The research effort of West-Central Alberta, in the winter of 2001/02, has focused on completing the final year of the initial 3-year research plan and developing subsequent research efforts. The Masters thesis of Tara Szkorupa, on caribou habitat selection at multiple scales, has been accepted. Tara's findings along with Paula Oberg's research on caribou response to linear features in the RedRock/Prairie Creek Range, and research results from the boreal caribou program are being employed to define caribou habitat and assess habitat effectiveness in westcentral Alberta. With the anticipated completion this summer of Gerry Kuzyk's research on the response of wolves to cutblocks, the initial research plan will be complete and the application of findings facilitated. Bob Lessard's research into the relationships between wolves, ungulate species, and land use has been initiated with specific regard to implications for caribou. The research subcommittee has identified 15 questions categorized into wolf, caribou, and human activity groupings, for future investigations. The questions are assessed against 5 criteria of: (1) Importance to caribou conservation, (2) Availability and attainability of existing data, (3) Specificity to allow achievement, (4) Scope of interest among stakeholders, and (5) Uniqueness of question to west-central Alberta. Ten of the identified questions meet 4 or all of the criteria. We expect that several questions can be combined. The committee is targeting the completion of a draft research plan by early summer for implementation in the winter of 2002. For more information on the research program, contact Jeff Kneteman at Jeff.Kneteman@gov.ab.ca or 780-865-8265.
When annual recruitment, defined as the number of calves surviving to yearling age, replaces annual adult mortality, the result is population stability. Consequently, the West Central Alberta Caribou Standing Committee’s (WCACSC) Research Sub-committee considers these two demographic metrics cornerstone “measuring sticks” of success or failure of land management strategies relative to woodland caribou conservation. Tracking woodland caribou population size is a very challenging and expensive undertaking in west-central Alberta. Given this species use of mature forests in winter, it is difficult to detect all animals during aerial inventories at this time of the year. In recent years, an increase in the number of radiocollared animals has provided the opportunity to estimate numbers with greater confidence through the “marked-resight” technique. Nonetheless, due to their relatively low density, this approach still requires extensive helicopter coverage of heavily forested landscapes. Plans of the current program call for this to be accomplished at a limited 5-year interval. A more achievable and economical approach on an annual basis is to track adult female survival and calf recruitment. Radiocollared females are monitored regularly (ideally monthly) and survival estimates are updated after each interval. The same approach could be used to track calf survival. However, radiocollaring caribou calves has been attempted, but with limited success. The main difficulty has been in capturing newborns in forested cover. Even mothers in the 2 mountain herds tend to be found in forested habitats following calving, which severely compromises capture opportunity. As a consequence, monitoring calves “at heel” or classifying calves in composite samples obtained during aerial surveys is a “fall-back approach” for obtaining this demographic metric. Continued on page 4 …...
Research Oil & Gas Industry partners with Alberta Fish & Wildlife on Project to Recover Linear Disturbances By Carol Engstrom P.Biol, Husky Energy The Oil and Gas Industry is taking an active role in the recovery of linear disturbances in the West Central Caribou Range. There are over 300 abandoned wellsites in the caribou range and each of these has an associate road and pad. These wells have been drilled and abandoned over the past 50 years and are in various vegetative states. If we can eliminate these past footprints from the landscape, we will be securing future habitat for caribou. Last newsletter, Tara Szkorupa wrote an article detailing the work completed on Linear Recovery in 2001. The project is based on the research conducted in the past that states that caribou avoid roads, seismic lines, and pipelines. Starting in the spring 2002 we will build upon the work completed by increasing the number of project areas and the number of linear disturbances that will be reclaimed.
This year the project areas will include Little Smoky, RedRock/Prairie Creek, Red Earth, and Firebag. We are in the process of hiring a project manager
Producers Group. To date a total of $350,000 has been raised When the Energy Industry goes about exploring for oil and gas, they create a
Pipeline right-of-way, photo by F. Schmiegelow
to oversee the Little Smoky and the RedRock/Prairie Creek project areas. The funding for this project is through the Habitat Stewardship Program, the Alberta Conservation Association, Canadian Association of Petroleum Producers, and the West Central
number of impacts on the landscape. These include seismic lines, construction of roads, wellsites, and pipelines. Our practices have improved in the past 10 years so that our industrial footprint in the future will be greatly reduced. For example, it is now
common practice to use low impact seismic which reduces the line width from about 8m to less than 3m. High blading is also employed so that the duff layer on the forest floor is left intact. Remote telemetry at wellsites reduces the frequency that we have to visit each well site and we work to follow existing disturbances when constructing roads and pipelines. We are also working with the Forest Industry to common corridor access when ever possible. The Energy Industry is excited about the possibility of returning its historical footprint on the landscape to usable caribou habitat. We believe that securing habitat for the future is one way to ensure that caribou will exist on the landscape. For more information on the recovery project, contact Carol Engstrom at carol.engstrom @huskyenergy.ca or 403-2986175.
2002 Caribou Collaring Program The WCACSC has radiocollared caribou in 3 herds: RedRock/Prairie Creek (RRPC), A la Peche (ALP), and Little Smoky (LSM). This past February, the WCACSC collared caribou in the LSM and ALP herds. â€˘ On the LSM herd, 5 GPS 2000 and 5 GPS 2200s collars were deployed. â€˘ On the ALP herd, 6 VHF collars were deployed, as well as 4 GPS 2000 collars along Highway 40.
Caribou capture, photo by C. Rohner, WCACSC
The data from the GPS 2000 collars will be available in 1 year and in 2 years for the GPS 2200s, unless a mortality or collar failure occurs.
Currently, the RRPC herd is monitored by 10 GPS collars and 19 VHF collars; ALP has 29 VHF collars; and LSM has 8 GPS collars, and 11 VHF collars. Two of the LSM GPS collars were retrieved in April 2002. Since 1998, GPS data has been retrieved from 42 female caribou: 33 in RRPC, 3 LSM, and 4 in ALP (Highway 40 animals). For more information on the caribou capture program, contact Kim Lisgo at email@example.com or 780-4920887.
Research Canfor Snow Tracking Program By Tom Sterr, Canadian Forest Products Ltd.
Canfor’s Forest Management Area contains 15% (77,228 ha) of the total range of the Little Smoky Caribou herd. As part of our commitment to maintaining caribou habitat, Canfor has elected to conduct aerial tracking of this area. This program is based on the protocol developed by Weyerhaeuser Company for the RedRock/Prairie Creek caribou range. Kent Brown, Wildlife Biologist for Terrestrial Aquatic Environmental Managers Ltd. who helped to develop this program, has been retained to manage Canfor’s tracking program. Twenty-three transects based on a 2-km interval are flown at 30-60 km/h at tree-top height in a helicopter. Identifiable tracks of ungulates and wolves are recorded on a 1:15000 scale map. In some cases, landing is required to verify tracks by back tracking until identifiable tracks, hair or fecal pellets are found. Human activities such as quad, snowmobile, seismic and maintained roads are also recorded if they are present in the caribou range. Three days are required to complete this portion of the project (weather permitting). This year due to lack of snowfall, tracks were up to 1½-months-old. At first we were concerned that identification of sign would be impossible, however after trying, it was concluded that sign was good and would provide a look at movement across the landscape on a longer time frame than normally captured. The largest amount of sign was located in the southern portion of the Forest Management Area. This was associated with the fen and bog complexes, feeding was also noted on abandoned well sites and in dry pine stands with southerly exposure in this area. Monitoring of collars was also done during flights and collar frequencies were recorded. Out of 10
Seismic line, Canfor photo
collars, 8 were recorded and these results were provided to Fish & Wildlife. This year, Tara Szorukpa from NRS was able to fly with us for one day as an observer to see this portion of the Little Smoky Caribou range. It is true that biologists sometimes get out of the office. This year marked the third year of track surveys and definite trends are becoming apparent. However, snow cover for the last 3 years has been minimal and may influence the results. Hopes are to fly this survey at a time when there is more snow to see if it has any effect on the trends that are showing. Maps and reports are supplied to NRS and the WCASC and are available from Canfor. With the ability to overlay the track surveys on AVI, we hope to use this in our planning process to maintain caribou habitat. As with any study new questions always arise, some of these are:
Fen-bog complex, Canfor photo
• The potential for lichen occurrence and therefore range suitability could be assessed using techniques similar to those developed for Canfor Chetwynd division, even though as work has been done in a mountain scenario it may be transferable into the boreal for predictive work.
For more information on Canfor’s snow tracking program, contact Tom • Lichen occurrence and increase Sterr at firstname.lastname@example.org or 780and decrease in relation to crown 538-7746. closure,
Research Continued from Page 1 ... Documenting calf-cow ratios in late winter/early spring is preferred before aerial survey conditions deteriorate due to melting snow. However, the 2 mountain herds (A la Peche and RedRock/Prairie Creek) are surveyed in late fall/early winter when groups are in the process of migrating to forested winter range. At this time, the animals are still in alpine habitats with much better visibility and they are concentrated on front ranges in the mountains, reducing the area that must be searched. The census of mountain herds at this time allows survey crews to either classify adults at close range or, if required, land to classify herds via spotting scopes. This permits yearling males to be differentiated from adult females by the presence of a penis sheath. When this classification can be accomplished, the ratio of calves to cows can be calculated directly. If animals are located in dense forests, it is very difficult to classify adults. In this case, the survey simply results in % calves in the composite aerial survey sample. To obtain a calf-cow ratio, the % of males based on previous surveys is subtracted from the adult portion. This provides an estimate of the number of adult females, which then can be divided into the number of calves to provide the calf-cow ratio and multiplied by the adult female survival rate to provide an estimate of recruitment. In west-central Alberta, the mean calfcow ratio has varied from 0.224 to 0.314 depending on the herd (Table 1). The annual assessment of recruitment is compared to the annual survival rate of adult females to calculate the “trajectory” of the population. Because males tend to be surplus to the population, population tracking can be simplified by tracking outcomes for females only. Consequently, the population at the end of the year is equal to the number of adult females that survived the year plus the number of female calves that survived their first year. Since calves cannot be readily sexed during aerial surveys, a 50:50 sex ratio of calves is assumed. For example, starting with
Alberta Fish and Wildlife Division photo
Table 1. Woodland caribou calf-cow ratios in aerial surveys, standard deviation, and the number of surveys and years that ratios were obtained for 3 herds of woodland caribou in west-central Alberta.
Herd* ALP LSM RRPC *
Mean CalfCow Ratio 0.277 0.224 0.314
Standard deviation 0.109 0.187 0.119
Number of Surveys 9 6 10
Years 1991 – 2001 1982 - 2001 1990 - 2001
ALP = A la Peche, LSM = Little Smoky, RRPC = Redrock/Prairie Creek
a theoretical number of 100 females, an observed adult female survival rate of 90% and a calf-cow ratio of 0.29, the projected population of females at the start of the next year would be: 100*0.90 (# of adult females) + (100*90) *0.29/2 (# of female calves) = 90 adult females + 13 female calves = 103 adult females in Year 2
In addition, future population trajectories can be estimated by randomly choosing adult female survival and calf-cow ratios from the statistical distribution around the means calculated from the existing data and projecting them over time (i.e. 20-year projection). When replicated a number of times (e.g. 1000 replicates), this approach can provide an “assessment of risk” associated with population performance based on the data already collected over a number of years. This is a very simplified approach to calculating population performance. For example, true recruitment is defined as the number of females entering breeding age (caribou
females would normally breed at 2.5 years of age and produce a calf at age 3). Since the WCACSC program has not collected age specific survival, the assumption is that survival of yearlings is similar to adults (3 years) based on data published from other herds. One of the advantages of tracking the individual parameters of population response is that the mechanisms affecting the overall outcome are measured annually, and in some cases (adult female survival), monthly. Consequently, if the 5-year interval population estimate is smaller or greater than the previous estimate, data are available to see if it was the outcome of calf recruitment, adult female survival, or both. By providing an assessment of year to year variation in these important population parameters, population persistence can be tracked annually and projected into the future: a useful tool for measuring the success of caribou conservation in west-central Alberta. For more information contact Kirby Smith at Kirby.Smith@gov.ab.ca or 780-723-8248.
'Research News' is intended to update members of the West-Central Alberta Caribou Standing Committee (WCACSC) about recent highlights of supported research, which are being prepared for final products. All results are preliminary and for information purposes only, and cannot be used without permission by the authors.
Published on Apr 17, 2014