Seasonal movement and activity of Akia-Maniitsoq caribou cows in West Greenland as determined by satellite. Technical Report No. 99

n May 2008 GPS satellite collars were deployed on 40 cows from the AkiaManiitsoq (AM) caribou (Rangifer tarandus groenlandicus) population. In the period 
2008-2010, the satellite-collared cows provided locations, which we analysed for 
movements, spatial distribution, calving sites, location attributes, seasonal activity 
periods, and habitat resource selection. The AM caribou are substantially less 
documented than herds in North America. The results in this report are particularly 
valuable for management in Greenland because they establish a baseline for AM 
habitat use in the current absence of significant development and infrastructure in 
the Central region. However, the short study period and small sample size, 
exacerbated by high mortality, weaken results. Although obtaining collar data in 
Greenland is difficult and costly, a longer time series with a stable large number of 
collared caribou is necessary before sweeping conclusions can be supported. 
AM cows behave similarly to the mountain ecotype of caribou rather than the 
barren-ground. Calving was not confined to specific exclusive calving grounds close 
to the Ice Cap. Birthing cows spaced-away in a continuum across the entire Central 
region, from seacoast to Ice Cap. There is little relevance to protecting specific 
exclusive calving grounds in the AM region. Instead, conservation measures would 
profit from applying a broad-scale habitat management approach to the widespread 
AM calving habitat. Elevation was a good predictor for probability of cow occurrence 
at calving. Whether in a xeric zone or not, south facing slopes around 600 m elevation 
with snow were favoured. Although timing and width of the emergent vegetation 
period and possibly rain avoidance may be the driving factors behind choice of high 
elevation for calving by parturient AM cows, these remain to be investigated. AM 
calving appears to begin earlier than previously assumed, and suggests that the 
period for protection measures might be shifted forward. Habitat possessing the 
preferred attributes for birthing comprises 42-45% of the Central region. Thus 
although calving range is essential for caribou production, at present it is not likely 
limiting the AM population. However, given the high fidelity by AM cows to 
previous birthing sites, a warming Arctic or anthropogenic influences could have 
negative impacts if cows are displaced to habitats less favourable for calf survival. 
Mortality among satellite-collared cows was high and much appeared due to 
harvest. If common to the entire population, this would have played a major role in 
the decline of AM abundance from 2001 to 2010. 
Patterns of annual movement confirmed a southwest-northeast axis. Distance 
moved could be short, with individuals typically at the western end of their axis in 
winter and eastern end in summer. Each cow utilized just a fraction of the available 
area. This strongly indicates population sub-division within the Central region and 
suggests that the entire AM population will not be influenced when either stochastic 
weather events or management actions affect only a portion of the region. 
Patterns of seasonal movement revealed 10 seasonal activity periods, which 
were associated with specific habitat attributes. Elevation was the primary habitat 
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attribute that varied significantly across the seasonal activity periods. Breeding 
occurred at low elevations. If hunting seasons coincide with the rut, then human 
disturbance may negatively influence breeding and subsequently calf production. 
Caribou vulnerability to harvest would also likely increase because of their relative 
accessibility to hunters. 
Daily movement patterns varied throughout the year. Cows moved least in 
early March making it optimal for aerial survey. July had maximum movement, 
suggesting insect harassment as the cause and supporting the necessity of insect 
relief habitat. During the calving period, a characteristic daily movement pattern was 
assumed to indicate a birthing event, i.e., rise from normal immediately preceding a 
sharp drop to near zero and thereafter a gradual rise. In future, birthing could be 
validated by visually locating satellite-collared cows by airplane or helicopter, or
equipping the satellite-collars with video capability.
Habitat attributes are not evenly distributed. Relative to the entire Central 
region, and in contrast to calving habitat, the available area is small for late summer, 
fall and winter habitats. These could be limiting for the AM population. Specifically, 
the largest tract of winter habitat, Akia, albeit still small in size, is vulnerable to south 
westerly storm systems that can render winter forage unavailable or energetically 
costly to access. Thus, special attention and protection through fine-scale habitat 
management may be appropriate. AM caribou abundance would likely benefit if for 
those habitats that are scarce, a) caribou access was preserved, b) anthropogenic 
disturbance was mitigated, and c) that densities of AM caribou were kept below 
carrying capacity of these limited ranges. 
Management is best tailor-made to the population, the seasonal activity under 
consideration and the amount of habitat available for that activity. Conservation 
efforts should address not just one several seasonal ranges vital to reproduction, 
insect relief and survival. Protecting parturient cows and their birthing habitat is not 
a one-shot cure for ensuring recovery or sustainability of caribou populations. 
Caribou roam. Globally, caribou range shifts are common, even for ‘sacrosanct’ 
calving areas. Thus, management must consider conserving currently unused areas 
for potential future use by caribou. Meanwhile, human influences on the landscape 
are recognized factors that can exacerbate caribou declines. In North America, the 
current threshold proposed for preventing caribou decline, is that 65% of the total 
range remains unexposed to human disturbance. Proactive management and 
conservation directed towards preserving large undisturbed intact landscapes, 
relevant for several seasonal activities and their movement corridors, would foster 
caribou conservation now and for future generations.