The use of a long-acting tranquilizer (zuclopenthixol acetate) and live video monitoring for successful long-distance transport of caribou (Rangifer tarandus)

Long-distance transport of caribou (Rangifer tarandus) can result in morbidities and mortalities. This case report describes the use of a long-acting tranquilizer, zuclopenthixol acetate (ZA) and live video monitoring (LVM) to transport caribou over 2300 kilometers. Two groups of captive caribou were transported from Fort St. John, British Columbia to Dryden, Ontario (n=14; 28.5 h transport) and Anchorage, Alaska (n=11; 32 h transport). The day prior to transport, caribou were administered ZA at 1 mg/kg via deep intramuscular (IM) injection. Digital video cameras allowed for live observation of caribou during transport. Still images of videos from each compartment in the Ontario transport were analyzed for percentage (%) lying versus standing over three time periods (Day 1, Night, and Day 2). Overall, caribou spent 57% of the transport lying down, with the highest percentage occurring at night (73%). As group size and animal density decreased there was a trend for caribou to spend more time lying down. Three animals developed extrapyramidal effects to the ZA and were effectively treated with midazolam at 0.2 mg/kg IM. There were no significant visible injuries or mortalities during or up to 6 weeks post-transport. Zuclopenthixol acetate and LVM were used to successfully transport caribou over long distances and should be considered in future translocations to improve animal welfare during transport.

Monitoring recovery of overgrazed lichen communities on Hagemeister Island, southwestern Alaska

Understanding the recovery rate of overgrazed lichen communities has value to mangers of lands in northern regions. We describe lichen community composition and present recovery rate measurements for a 12-year period following overgrazing by reindeer (Rangifer tarandus) on Hagemeister Island, Alaska. Reindeer were removed from the island in 1993 following overgrazing and average total lichen biomass increased from 504.2 kg/ha (SD 205.4) in 2003 to 795.3 (SD 489.6) in 2015. We estimate time to recovery with three competing growth curves which estimate grazeable biomass may be reached in 34-41 years. However, estimates of full recovery to climax biomass varied among the models, ranging from 71 to 400 years. In 2015, lichen communities were composed of various mixtures of at least 78 lichen taxa, and were dominated by Cladina stygia and other important reindeer forage species. While reindeer overgrazing diminished forage quantity, it did not extirpate preferred forage taxa.

Reindeer fidelity to high quality winter pastures outcompete power line barrier effects

We investigated barrier effects of a 66 kV power line established in 1966 before and after the line was upgraded to 132 kV in 2004 over a period of 44 years (1974-2017) in the North Ottadalen wild reindeer area (3245 km2) of which 1038 km2 are in use as winter pastures. The power line transects a peninsula (135 km2) with high quality winter pastures in the southeast periphery. The reindeer population originated from a nucleus herd of 402 animals of domestic origin released in the area in 1964-1965 and 100 resident wild animals. Yearly winter survey started in 1974 and reindeer were first surveyed south of the 66 kV power line in 1982. Comparing the number of animals recorded in the peninsula vs. the number of individuals expected relative to available grazing area during the three periods (1974-2004, 1982-2004 and 2005-2017), the number of animals recorded in the peninsula was 3.6–4.9 times higher than expected. Since the upgrade of the power line, a substantial part of the reindeer population grazed in the peninsula every year. We therefore conclude that there was no long-term barrier effect from the original power line and no barrier effects at all from the upgrade. However, during the first 5 surveys of this study, there were no animals in the peninsula. Therefore, even if there are several possible reasons for this, we cannot exclude the possibility of short-term barrier effects resulting from the construction of the original power line. Our results support recent studies that report no effects from existing power lines and contrast some previous findings that have reported strong long-term barrier and avoidance effects of such infrastructure for Rangifer migration and grazing behaviour.

A review of reindeer lichen (Cladonia subgenus Cladina) linear growth rates

Cladonia subgenus Cladina (the reindeer lichens) can be a dominant part of terrestrial ecosystems worldwide. They are particularly abundant in arctic-alpine and boreal regions, where they are a primary food source for woodland caribou/reindeer in winter months. Determining the growth rates of reindeer lichen is important for understanding and managing lichen regeneration following disturbances such as timber harvesting, mining, grazing, and wildfire. Regeneration and rehabilitation rates can be calculated with greater accuracy when growth rates are well understood. We provide a summary of 17 studies from 6 countries that determined the linear growth rates of three reindeer lichen groups, Cladonia arbuscula/mitis (mean = 4.7 mm/yr.), C. rangiferina/ C. stygia (mean = 5.1 mm/yr.), and C. stellaris (mean = 4.8 mm/yr.). We use linear growth rates as a proxy for over-all growth and biomass. Variables found to influence lichen growth rates are also discussed, which include light, moisture, temperature, air pollution, acid rain, precipitation, snow accumulation, substrate, age of individuals, and type of disturbance. These results can assist land managers in developing more accurate strategies for restoring lichens in disturbed areas.

Spatial structure of boreal woodland caribou populations in northwest Canada

Local population units (LPUs) were delineated in Canada’s recovery strategy for threatened boreal woodland caribou (Rangifer tarandus caribou). Population viability analyses central to contemporary integrated risk assessments of LPUs implicitly assume geographic closure. Several LPUs in northwest Canada, however, were in part delineated by geopolitical boundaries and/or included large areas in the absence of evidence of more finely resolved population spatial structure. We pooled >1.2 million locations from >1200 GPS or VHF-collared caribou from northeast British Columbia, northwest Alberta and southwestern Northwest Territories. Bayesian cluster analysis generated 10 alternative candidate LPUs based on a spatial cluster graph of the extent of pairwise co-occurrence of collared caribou. Up to four groups may be artifacts in as yet under-sampled areas. Four were mapped LPUs that were conserved (Prophet, Parker, Chinchaga and Red Earth). One small group between Parker and Snake-Sahtaneh known locally as the “Fort Nelson core,” and outside any mapped LPU, was also conserved. Finally, one large group, at >136000 km2, spanned all three jurisdictions and subsumed all of six delineated LPUs (Maxhamish, Snake-Sahtaneh, Calendar, Bistcho, Yates, Caribou Mountains) and part of southern Northwest Territories. These results suggest less geographic closure of LPUs than those currently delineated, but further analyses will be required to better reconcile various sources of knowledge about local population structure in this region.

Are the Jameson Land muskoxen, Northeast Greenland, in decline?

The Jameson Land region contains the largest muskox population in Northeast Greenland. In the period 1980-1990, late winter population size averaged 3,645. A late winter 2000 survey estimated ca. 1,705 muskoxen. Although no further late winter surveys for muskox abundance have occurred since, there have been two summer bird surveys, which recorded incidental observations of muskoxen, i.e., 607 in 2008 and 610 in 2009. We report on muskox observations obtained in a subarea of Jameson Land during the summer 2016 ground survey for birds. Although in the 1982-2000 period this subarea averaged 1,153 ± 346 muskoxen, we observed 138 individuals and a low calf number. The few muskoxen observed and poor calf production suggest population decline. We briefly discuss possible factors that could influence muskox mortality and population abundance. Surveys specific to muskoxen are necessary to ascertain current population abundance, demographics and trend.

Aerial survey and telemetry data analysis of a peripheral caribou calving area in northwestern Alaska

With industrial development expanding in the Arctic, there is increasing interest in quantifying the impacts of development projects on barren ground caribou (Rangifer tarandus granti). The primary data source to assess caribou distribution and predict impacts in remote areas of Alaska has shifted in recent decades from aerial survey data to telemetry data, but these techniques have different strengths and weaknesses. The ranges of two caribou herds, the Western Arctic Herd and the Teshekpuk Herd, overlap in northwest Alaska between Wainwright and Atqasuk, Alaska. Based on long-term telemetry data sets, this region was thought to be outside of the core calving ranges of both herds. Calving has long been reported to occur in this general area, but early reports assumed caribou were from the Western Arctic Herd and only one systematic aerial survey of caribou density and distribution during calving has been conducted in this area in recent decades. Following interest in industrial development in this area, we conducted aerial strip-transect surveys during early to mid-June 2013–2015 to directly assess the density and distribution of caribou in the area and we used existing telemetry data to compare our results to the seasonal distribution of both herds. Total caribou densities varied between 0.36 and 1.06 caribou/km² among years, and calf densities varied 0.04 and 0.25 calves/km² among years. Contrary to assumptions by early researchers in the area, telemetry data indicated that caribou in this area during early to mid-June were from the Teshekpuk Herd. The use of telemetry data alone underestimated the importance of this area for calving, but the combination of aerial surveys and telemetry data provided complementary information on caribou use of this area showing the importance of collecting the appropriate types of data for assessing potential impacts of development on caribou.

Behavioural responses of southern mountain caribou to helicopter and skiing activities

Helicopter- and snowcat-supported backcountry skiing is a unique industry that is widespread throughout southern mountain caribou habitat in British Columbia. We analyzed standardized caribou encounter data collected by operators under an agreement between the BC government and Helicat Canada. Average reported encounter rates were low for helicopters (0.6%) and skiing groups (0.1%); however, encounters were likely underreported due to factors that affect caribou sightability. Although helicopters encountered caribou more frequently than skiing groups, caribou were detected from helicopters at greater distances than by skiers. We used Bayesian network models to assess the independent contribution of different factors to the behavioural response of caribou to encounters. Encounter distance was the most important factor in both helicopter and skiing models. Larger groups of caribou responded strongly to skiers but not to helicopters, although the independent effect of this factor was small in both models. Larger helicopters elicited stronger reactions from caribou than smaller machines and was responsible for 25% of the modelled variation in caribou response. Encounters with helicopters at distances of 100–500m had a 78% probability of eliciting a concerned-to-very-alarmedresponse from caribou, while skiers at a similar distance had a 60% probability of eliciting the same response. The probability of concerned-to-very-alarmed responses dropped to <20% at encounter distances of >1000 m. These results indicate that initial encounter distance is the key variable to manage risk to caribou of helicopter and skiing encounters. Ongoing feedback on the effectiveness of management practices is critical to ensure the continued viability of industries operating in caribou habitat.

Metric and non-metric guides for the determination between fore- and hindlimb phalanges of Rangifer tarandus

Phalanges are a great untapped resource in the zooarchaeology of Rangifer tarandus. The utilization of this resource, however, is constrained by a current inability to consistently differentiate fore- from hindlimb phalanges in a mixed assemblage. The ability to separate and identify forelimb and hindlimb phalanx 1 (PI) and phalanx 2 (PII), as well as to recognize and identify other small bones of the hoof, leads to great opportunities for archaeologists. In large scale-analysis, this capacity allows a greater ability to determine minimum number of individuals and assess butchery and transport practices. In the examination of individual life histories of Rangifer tarandus, these designations allow a more precise study of pathology and entheseal change, which can shed light on adaptation, foraging strategy, and human-animal interactions. This study presents qualitative and quantitative methods for the differentiation of PI and PII of the fore- and hindlimbs and describes other bones of the hoof. Metric techniques were developed to differentiate fore- from hindlimb phalanges using non-invasive, non-destructive, and simple methods. The efficacy and accuracy of these methods were assessed using blind testing by students and staff. The average success rates of metric analysis yielded 87% accuracy for determinations of fore- versus hindlimb PI and 92% accuracy for determination of fore- versus hindlimb PII. These results show that this method could benefit researchers working with Rangifer tarandus remains.