High Arctic Caribou Literature Review by Amy Harff

1. Past, Present and Future Impacts of
Climate Change on High Arctic
Canadian Caribou Populations
Amy Harff
Changing Arctic Ecosystems
Literature Review
11/15/20

2. 1
Background:
Climate change is impacting species all
around the world, and as the Arctic warms at
nearly twice the global average (IPCC, 2007),
Arctic ecosystems and Indigenous
communities are especially vulnerable
(Anisimov et al., 2007). These high-latitude
ecosystems exhibit strong signs of climate
warming, low biodiversity and minimal
confounding anthropological factors which
makes them ideal systems for studying the
relationship between species, humans and
changes in their shared environment (Kutz et
al. 2009). Changing temperatures, melting sea
ice and extreme weather associated with
climate change have particularly affected the
caribou and reindeer (Rangifer tarandus)
populations in the Arctic, leading to an overall
56% population decline in the past two
decades, with some herds declining more than
90% (Russell et al., 2018).
Rangifer tarandus is the most common large
terrestrial herbivore in the circumpolar region
(Mallory and Boyce 2017). This species is not
only an important regulator of Arctic
ecosystems, but is also essential to High
Arctic Indigenous communities who rely on
caribou for cultural identity, tradition and
social cohesion (Taylor 2005 ; Kutz et al.,
2009 ; Kaluskar et al., 2019 ; Ford et al., 2007
; Mallory and Boyce 2017). Rangifer tarandus
is a key species in the arctic food web
contributing to nutrient cycling between
terrestrial and aquatic systems and the
abundance of predators and scavengers.
Caribou population decline is emblematic of
greater species decline around the world, so
understanding how this species is impacted by
climate change can provide insight into the
ability of species to adapt. Given the extensive
distribution of habitats that Rangifer tarandus
populations inhabit throughout the Arctic,
generalizing how climate change will impact
the whole species is quite challenging
(Mallory and Boyce, 2017), thus this literature
review primarily focuses on the Canadian
Arctic caribou populations such as the Peary
caribou (Rangifer tarandus pearyi) and
Dolphin and Union caribou herds (Rangifer
tarandus groenlandicus x pearyi). The
Dolphin and Union caribou were once
considered to be part of the Peary subspecies,
but genetic studies now show that these two
populations are distinct (NWT, 2018).
Nevertheless, these caribou face similar
challenges due to their overlapping habitat
range, remote island locations and shared
vulnerabilities parasites.
While many Rangifer tarandus populations
have declined globally (Mallory and Boyce,
2017; Vors and Boyce, 2009 ; Festa-Bianchet
et al., 2011), the Peary caribou has
experienced the most drastic population
decline of Rangifer tarandus subspecies
(Kaluskar et al., 2020). Recent estimates place
the total population at around 13,200 mature
adults which inhabit a large range of over
800,000 km2
of the Canadian Arctic
Archipelago including the eastern and western
Queen Elizabeth Islands, Banks Island,
northwestern Victoria Island, Prince of Wales
Island, Somerset Island, and the Bathurst
Island complex (see Figure 1 below)
(COSEWIC, 2015). Most of the Peary
caribou’s historic habitat is untouched by
anthropogenic infrastructure or industrial
developments, however, as increasing

3. 2
Figure 1: Peary caribou subpopulations (COSEWIC,
2015)
temperatures make this area more accessible
and hospitable, it is possible that this will
change.
This subspecies has witnessed an overall
population decline from about 50,000 caribou
since 1961, with dramatic decreases of up to
98% in the 1970s and 1990s, leaving only
about 5,400 in 1996 (Miller and Gunn, 2003 ;
COSEWIC, 2015). These drastic population
reductions led the Committee on the Status of
Endangered Wildlife in Canada (COSEWIC)
to declare the Peary caribou as Threatened in
1979 (Gunn et al., 1979) and as Endangered in
1991 (COSEWIC, 2004; Miller,
1991). While the population has
increased since then, of four
subpopulations, two are showing an
increasing trend, one is stable and
the fourth was recorded to have
fewer than 10 individuals in 2005,
showing no signs of recovery
(COSEWIC, 2015).
Peary caribou are considered to have
a Very High-Medium threat impact.
This is due to an accumulation of
numerous small threats such as
increased shipping routes which
break up ice and disrupt migration
patterns, increased exposure to
pathogens, and increased frequency
and intensity of extreme weather
events such as freezing rain
(COSEWIC, 2015 ; Vors and
Boyce, 2009). Extreme weather such
as freezing rain and heavy snow
events are responsible for
spatiotemporal changes in plant
phenology which impacts caribou populations
by altering their foraging patterns and food
availability (Vors and Boyce, 2009).
Similarly, increased temperatures are altering
insect phenology with earlier emergence and
increased longevity and abundance of
parasites and pathogens (Vors and Boyce,
2009). More specific extreme weather impacts
will be discussed later in the “Climate
Change’s Impacts on Abiotic Factors” section
below.
Similarly, the Dolphin and Union caribou
subspecies has also been listed as Endangered
in 2017 (COSEWIC, 2017). Dolphin and

4. 3
Union caribou populations
were estimated to be around
30,000 in 1997, declining to
about 18,000 in 2015, with
only about 4,000 left in 2018
(NWT, 2018). Inuit
Qaujimajatuqagit have
observed changes in the
distribution of Dolphin and
Union caribou and have also
noticed the declining
populations due to predation,
hunting, and drowning from
breaking through sea ice
(COSEWIC, 2017). Dolphin
and Union caribou summer
on Victoria Island and winter
on the mainland of Nunavut
in windy areas with shallow
snow cover (see Figure 2).
Dolphin and Union caribou and Peary caribou
were once considered to be the same
subspecies, however Dolphin and Union
caribou are slightly larger and have darker
pelage (COSEWIC, 2004). Both subspecies
are specially adapted to survive harsh winter
conditions. Peary caribou are adapted to live
in the sparsely vegetated environments of the
polar desert and arctic tundra (COSEWIC,
2015) Their compact body size, heat
conservation and hooves for foraging under
wind-driven snow allow them to better survive
the harsh winters. Both caribou subspecies
also have white pelage in winter which allows
them to blend in better with their surroundings
and avoid predators. In summer, their pelage
is slate gray to match the more snow-free
terrain (COSEWIC, 2015). These caribou
populations are specifically adapted to their
Figure 2: Dolphin and Union caribou population range
(COSEWIC, 2017)
intense Arctic environment, which means that
as climate change alters their environment,
their niche Arctic adaptations may actually
hinder the population’s ability to adapt.
The adaptive capacity of these northern
ecosystems is further limited due to their
spatial constraints (Vors and Boyce, 2009). As
tree line advances north, predator and parasite
ranges expand and the Arctic Ocean warms,
leading to less ice coverage, there is little
place for Peary and Union and Dolphin
caribou populations to migrate (Miller and
Gunn, 2003).
Literature Review Objectives:
This review will focus on how climate change
impacts the Peary caribou and the Dolphin and

5. 4
Union caribou populations, in the past, present
and in future predictions. While Rangifer
tarandus population fluctuations are
reportedly normal (Russell et al., 2018 ; Gunn,
2003 ; Vors and Boyce, 2009 ; Taylor, 2005 ;
Fauchald et al., 2017), it is important to
understand how climate change impacts
Canadian Arctic caribou populations. Climate
change has been linked to Rangifer tarandus
population decline, not all predicted effects
will be bad (Hulme, 2005). The effects of
climate change are also likely to shift over the
years as environmental conditions change
(Tews et al., 2007). Understanding how a
changing climate can exacerbate existing
threats to Canadian Arctic caribou can help
researchers better prepare for and help to
prevent future population declines.
While there are many climate change factors
that impact Canadian Arctic caribou, the focus
of this review is on changing seasonal
patterns, parasites and extreme weather
events. Other important factors of population
decline not fully discussed in this review
include forage availability, movement and
migration, predation and hunting, vegetation
changes, caribou adaptive capacity, and
habitat disturbance (Mallory and Boyce, 2017
; Tews et al., 2007 ; Vors and Boyce, 2009 ;
Festa-Bianchet et al., 2011). This review will
also examine how caribou population decline
in the Arctic has impacted and been observed
by native Inuit populations that rely on the
caribou for food security and cultural
significance.
Vegetation:
Plant productivity in the High Arctic is
generally very low, but less than 5% of the
total Peary caribou range is vegetated
(Nellemann, 1997). Fortunately, Peary caribou
are opportunistic foragers. Their diets vary
seasonally depending on forage availability
and nutritional quality (Kaluskar et al., 2020).
From June to August, Peary caribou diets
consist primarily of willow, grass, forbs, and
sedges. From September to May, legumes
(Larter et al., 2002) and lichens (Thomas et
al., 1999) are commonly eaten for their
digestibility. In the winter, only a fraction of
those foraging areas are accessible, so Peary
caribou primarily forage on ridges and well-
drained uplands, even though these are some
of the least productive vegetated areas (Larter
and Nagy, 2001). These areas are accessible,
however, due to limited or absent snow cover
which makes foraging for vegetation easier
(Tews et al., 2007).
Summer is a critical foraging time when
caribou populations recover from the lack of
nutrition during the previous winter and build
up body reserves for the coming winter
(Mallory and Boyce, 2017). During these
months, cows have the additional energetic
stress of lactation, and males need to build up
body reserves for the fall rut, both of which
require adequate nutrition (Mallory and
Boyce, 2017 ; Gerhart et al., 1996). Calves
also need to maximize their physical growth
rate and build body mass in order to increase
their chances of surviving harsh Arctic winters
(Vors and Boyce, 2009). Poor summer
foraging conditions have been associated with
reductions in fertility and overwinter survival
rates from failure to regain sufficient body
mass (Mallory and Boyce, 2017).

6. 5
Figure 3: Biomass in relation to forage inaccessibility
and subsequent caribou mortality (Tews et al., 2007)
As climate change impacts seasonal length
and temperatures, earlier and longer growing
seasons have been predicted to benefit
Rangifer tarandus populations (Tews et al.,
2007). Increased plant productivity due to
warming summer temperatures has been
associated with increased Svalbard reindeer
body mass (Albon et al., 2017). As Figure 3
shows, increased biomass strongly decreased
mortality rates because caribou were less
likely to starve during winter months (Tews et
al., 2007 ; Vors and Boyce, 2009). Starvation
has been a challenge for Canadian caribou
populations in the past, as extreme weather
events inhibited foraging through ice and
snow (Vors and Boyce, 2009 ; Mallory and
Boyce, 2017). Increased temperatures and
shorter winters may benefit Rangifer tarandus
populations by decreasing snowcover and
making vegetation easier to access (Mallory
and Boyce, 2017). Conversely, warmer
weather may also increase the frequency of
icing events that have caused previous mass
starvation by preventing access to vegetation
(Miller and Gunn, 2003). More detailed
information on extreme weather events is
discussed in the “Extreme Weather” section
below.
While Tews et al., 2007 suggests that longer
growing seasons should be beneficial to
caribou populations, Fauchald et al., 2017
found a strong bottom-up effect, where
increased plant biomass on summer pastures
due to a warmer climate is associated with a
decline in caribou populations. This study
suggests that climate-induced greening has led
to a deterioration of pasture quality.
Figure 4: Causal diagram of the relationship between
climate, plant biomass, and caribou (Fauchald et al.,
2017)
As shrub ranges have expanded northward
throughout the Arctic (Parmesan & Yohe,
2003), some plant species now growing in
caribou territory have strong anti-browsing
defenses. Fauchald et al., 2017 suggests that
these changes might be indicative of future
climate-driven shifts in caribou and plant
interactions from areas of low plant biomass
to habitats dominated by nonedible shrubs and
subsequently, diminished caribou populations.
Shrubification of the Arctic is also changing
the ground and air temperatures. In summer
shrub canopies shade tundra soils, which
keeps the ground temperature cooler (Loranty
et al., 2018). Shrubs also absorb more heat due
to the decreased albedo compared to snow,
which warms the ground in the winter. Given

7. 6
that winter is much longer than summer in the
Arctic, the decreased temperature in the
summer is shadowed by the increased winter
temperature. These changing temperatures are
part of feedback loops that increase CO2
atmospheric warming globally, but it is also
possible that increased ground temperatures
might be favorable for caribou in the winter as
it might make foraging for food easier if it is
buried under less snow. Conversely, shrub
range expansion and increased density of
shrubs and trees might lead to more fires
which would not only be deadly to caribou
populations but would also wipe out their
already scarce food resources. Arctic fires are
already becoming increasingly more severe,
frequent and spatially expansive, and more
fuel for fires (in the way of shrubs and trees)
would likely only increase these occurrences
(Loranty et al., 2018). More information on
fires is in the “Fire” section below.
Earlier spring season also means earlier peak
forage availability (Vors and Boyce, 2009).
Parturition typically coincides with the growth
of highly nutritious plants in spring, given that
calf growth depends on nutrient-dense plants
for building body mass required to survive
harsh Arctic winters (Post & Klein, 1999 ;
Weladji & Holand, 2006). As climate change
shifts the onset of spring earlier, caribou
parturition has not adapted to correspond to
the peak forage availability (Post &
Forchhammer, 2008). This “trophic
mismatch” can tax female body condition and
lower calf production because the mother and
calf are less able to meet their energy
requirements once the peak foraging period
ends. Post and Forchhammer, 2008 found that
offspring mortality increased and offspring
production decreased fourfold as temperatures
increased by more than 4ºC between 1993 and
2007.
Climate Change’s Impacts on
Abiotic Factors:
This section focuses on the different ways that
climate change is altering weather patterns
and other abiotic factors such as sea ice and
fire, and how these changes impact Arctic
caribou populations. While there are many
factors to consider, the primary ones include
fire, sea ice, temperature increase and extreme
weather. While most of these factors don’t
currently cause major stress to Arctic caribou
populations individually (except for extreme
weather), the cumulative impacts of these
changes threaten caribou populations, increase
vulnerability to parasites and diseases,
increase calf mortality and also impact
vegetation and foraging abilities (NWT, 2018
; Mallory and Boyce, 2017).
Fire:
Climate change is also predicted to cause
more variable weather and increased
temperatures create drier and hotter
ecosystems more prone to fires. The predicted
fire weather index is between 1.5 to 2 times
current rates in Canada (Thompson et al.,
1998). This is likely to change forest
composition, creating more homogenous
forests and favoring white-tailed deer
populations at the expense of moose and
caribou populations. Increased wildfire
activity in winter ranges may also degrade
vegetation quality and quantity for caribou,
while improving the vegetation for ungulate
species, allowing them to further spread north

8. 7
(Mallory and Boyce, 2017). Northern
Indigenous caribou hunters have also
witnessed the increased fire frequency within
the caribou range and have observed how this
impacts caribou migration patterns (Vors and
Boyce, 2009).
Sea Ice:
Ice surrounds the High Canadian Arctic
islands for most of the year. As the Arctic
warms faster than most of the rest of the
world, a phenomenon known as Arctic
Amplification, sea ice is experiencing historic
declines (Dai et al., 2018 ; Kumar, 2020).
Increased temperatures due to Arctic
Amplification cause the ice to melt more
rapidly, and more dark open sea absorbs more
longwave radiation which in turn creates a
feedback loop which further increases Arctic
Amplification (Dai et al., 2018). Not only is
multi-year ice declining, but the thickness of
the ice has also been observed to be
decreasing (Kumar, 2020). In September
2018, the sea-ice volume was three times
lower than in September 1979.
Changing sea ice impacts migratory caribou as
these populations rely on ice for safe crossing
between islands in winter. Warming surface
temperatures have already begun to change
the annual timing of sea ice and freshwater ice
formation and break-up (Mallory and Boyce,
2017). Between 1982 and 2008, sea ice
between Victoria Island and the mainland
formed 8-10 days later (Poole et al., 2010).
Thinner ice due to climate warming has been
associated with increased caribou drowning
and is altering caribou migration patterns,
often necessitating longer migration routes in
order to avoid bodies of water (NWT, 2018 ;
Mallory and Boyce, 2017). Longer distances
will also likely increase the migration
energetic costs, which threatens the caribou’s
already precarious balance between winter
body mass and forage availability.
While some studies show that caribou are
adept swimmers (Miller, 1995 ; Avgar et al.,
2013), others indicate that breaking through
ice can be fatal (Miller and Gunn, 1986 ;
Poole et al. 2010; COSEWIC, 2017). As ice
cover becomes increasingly thinner and more
absent for longer periods of the year, caribou
populations will have to adjust migration
patterns to avoid riskier times of the year, and
some are likely to perish during the
migrations. It is also possible that changing
sea ice conditions will restrict movement,
causing genetic isolation on islands and
potentially threatening population viability
(Mallory and Boyce, 2017).
Peary caribou in the Queen Elizabeth Islands
also live in a non-equilibrium grazing system
which is driven primarily by abiotic factors
such as ice conditions (Miller and Barry,
2009). Peary caribou rely on migration to
decrease the grazing pressure on specific
islands given their sparse vegetation and
possibly to reduce predation risk from wolves
(Mallory and Boyce, 2017). The Dolphin and
Union caribou population is also threatened by
increased ship traffic that can affect ice
formation and impact caribou migration
patterns, and by increased summer predators
in Victoria Island (NWT, 2018 ; Kaluskar,
2020).
As sea ice melt furthers Arctic Amplification
and contributes to increased heating of the

9. 8
Arctic, it is likely that the other climate
change impacts on caribou populations will
only increase.
Temperature Increase:
As surface air temperatures rapidly warm in
the Arctic, caribou populations are
increasingly vulnerable to increased heat,
insect abundance, extreme weather and loss of
sea ice (Mörschel and Klein, 1997 ;
COSEWIC, 2017 ; Mallory and Boyce, 2017 ;
Miller and Gunn, 1986). As already discussed
above, increased temperatures also impact
vegetation and predator habitat range
expansion, which further stress caribou
populations. Increased temperatures have also
been associated with decreased caribou
foraging, regardless of insect abundance
(Mörschel and Klein, 1997).
Extreme Weather:
Peary caribou are the most Canadian Arctic
caribou subspecies vulnerable to increased
frequency and severity of extreme winter
weather events due to their high arctic location
(Vors and Boyce 2009). From 1993-1998,
Peary Caribou populations declined 98% on
Bathurst Island (Miller and Gunn, 2003).
These die-offs were associated with heavy
snow and icing events from three successive
winters (1995-1997). As climate change
increases the frequency of extreme
weather events, Miller and Gunn warn that
Peary caribou populations will not be able to
recover (2003).
Extreme prolonged winter events can
devastate caribou populations when snow and
ice cover vegetation and essentially create a
barrier that prevents the caribou from being
able to forage (Tews et al., 2007 ; Miller and
Barry, 2009). It is less about the amount of
snowfall, and more related to the depth,
density and hardness of the snow cover that
can result in these unfavorable conditions
(Miller and Gunn, 2003).
While these abiotic factors have been
separated for clarity in the section above, it is
Figure 5. Distribution of observations of live Peary
caribou obtained by aerial searches in 1993 and 1998
given by sex and age class. (Miller and Gunn, 2003)
important to note that all of these changes are
not isolated from the others. As warmer
temperatures decrease sea ice extent,
exacerbate extreme weather events and
increase fire frequency and severity in the
Arctic, it is important to consider the
relationship between each of these abiotic
factors and how they create feedback loops
(Thompson et al., 1998).

10. 9
Parasites:
The predominant pests that harass Peary
caribou are warble flies (Hypoderma tarandi)
and nose botflies (Cephenemyia trompe), both
belonging to the family Oestridae (Downes et
al., 1986). Other known caribou pests include
mosquitoes (Culicidae), blackflies
(Simuliidae), and horseflies (Tabanidae)
(Hagemoen and Reimers, 2002). While
parasitism by protozoans and helminths will
not be discussed in this subsection, it is
important to note that climate change is
predicted to increase caribou parasitism by
other taxa in addition to the current pests
(Mallory and Boyce, 2017).
Parasites are not just predicted to expand
northward and impact future caribou
populations, they already have. Laaksonen et
al. describes caribou being attacked by large
swarms of blood-feeding insects of up to
8,000 mosquitoes per hour (2010). Mosquito
activity is positively correlated with air
temperature and subsequent mosquito
harassment is linked to poor caribou body
condition (Vors and Boyce, 2009).
Warble fly larvae was also found in 14% and
26% of two populations of Peary caribou in
1990 (Thomas and Kiliaan, 1990), and greater
than average numbers of larvae are sometimes
associated with poor health, decreased body
weight and less fecundity in female caribou
(Vors and Boyce, 2009 ; Hughes et al., 2009).
The Thomas and Kiliaan study (1990) found
that infestation levels of warble larvae in
caribou are impacted by climate, caribou
density, migratory behavior, caribou
avoidance behaviors, and intrinsic
immunological factors.
Protostrongylid nematodes have emerged
recently in the Arctic and are linked to climate
change (Kutz et al., 2009). Protostrongylidae
can be pathogenic and can cause pneumonia,
myositis and neurological disease in their
hosts. In 2010, Varestrongylus sp., a type of
lungworm, was recently discovered near
Ikaluktutiak and has since been suspected to
have traveled to the islands and mainland due
to migratory caribou populations (Kutz et al.,
2009).
Insect harassment is limited by the
environmental factors of temperature, wind
and precipitation (Downes et al., 1986). In the
past, there were periods of the Arctic summer
and fall that did not have significant pests due
to environmental factors limiting the period of
time conducive to insect activity (Mallory and
Boyce, 2017). As climate change warms
Arctic temperatures, insects are able to survive
for longer and the amount of pests is predicted
to increase.
Some studies have already observed a
correlation between warmer summers, caribou
body health decline and increased levels of
insect harassment (Mörschel and Klein, 1997 ;
Hagemoen and Reimers, 2002). Caribou ate
less and were more active in the presence of
oestrid flies, which was particularly apparent
in higher temperatures (Mörschel and Klein,
1997). Some studies have observed caribou
running and jumping for hours to avoid oestrid
flies, which means that more time is spent
expending energy than grazing (Hagemoen
and Reimers, 2002). Alternative methods to
avoid insects include spending time on windy

11. 10
hilltops, snow patches and other unproductive
areas (Mallory and Boyce, 2017).
In order to compensate for lost foraging time
in the summer due to increased insect
harassment, caribou may increase foraging
habits during times with less harassment (such
as in the evening) or after the insect season
(later in the summer) (Downes et al. 1986),
although some studies show that this is not
currently the case (Mallory and Boyce, 2017).
As climate change impacts Peary caribou
vegetation availability (Gould et al., 2003),
quality (Fauchald et al., 2017) and growing
season (Post & Forchhammer, 2008), caribou
may become more susceptible to parasitic
infections. Warming temperatures are also
associated with altered geographic
distribution, transmission rates, host-parasite
assemblages and life-cycle phenology of
pathogens (Mallory and Boyce, 2017). Not
only do animals in poorer health tend to be
more vulnerable to parasites, but the costs of
such infections can create a feedback loop
which further deteriorates the caribou body
condition and increases chances of future
infections (Beldomenico and Begon, 2010 ;
Thomas and Kiliaan, 1990; Tompkins et al.,
2011).
Northward expansion of alternate prey species
has also been observed in North America
(Thompson et al., 1998). The white-tailed deer
range expansion is of particular concern for
woodland caribou as deer often carry the
meningeal brain worm (Parelaphostrongylus
tenuis). While P. tenuis is harmless to its deer
host, it is deadly for caribou (Vors and Boyce,
2009). As white-tailed deer range expands, it
is likely that caribou will come into contact
with P. tenuis, and this may shift the wolf-
caribou-moose balance into one of primarily
wolves and moose.
Conclusion
Caribou current and predicted population
declines not only threaten the delicate Arctic
ecosystem balance, but also impact
Indigenous communities. Peary and Dolphin
and Union caribou are important cultural and
socioeconomic staples for traditional High
Arctic communities (Ferguson et al., 1998 ;
Vors and Boyce, 2009 ; Miller and Barry,
2009 ; Ford et al., 2007 ; Gun et al., 2000).
Caribou hunting and other traditional food
rituals account for between 40 and 60 million
(Canadian dollars) of Nunavut’s land-based
economy per year (Ford et al., 2007). While
there is no evidence that past hunting has
caused or even significantly contributed to the
Peary population decline (Miller and Gunn,
2003), Peary caribou populations have been
monitored by the Olokhaktomiut Hunters and
Trappers Committee (Ulukhaktok) since 1990,
with self-imposed restrictions (NWT, 2020).
Dolphin and Union caribou populations are
Endangered, and subsequent population
declines led to a hunting restriction in 2020
(Minogue, 2020). These restrictions, while
important for caribou survival, threaten the
Indigenous communities who rely on caribou
for food, clothing, artwork and income (Ford
et al., 2007, Vors and Boyce, 2009 ; Festa-
Bianchet et al., 2011).
Climate change’s impact on weather and sea
ice also makes accessing remote caribou
populations more dangerous, expensive and

12. 11
time consuming (Ford et al., 2007). Many
Igloolik travel over 150km to access caribou,
and their snowmobiles are vulnerable to
changing snow depth and textures. Given that
climate models indicate that these poor
conditions (ex. freeze-thaw cycles and
freezing rain) will likely increase in the future,
the future, the livelihoods of many caribou
hunters is becoming increasingly threatened.
These challenges are further exacerbated by a
slow erosion of hunting skills which is due to
increased community sedentary behaviors in
the 1960s and Canadian federal government’s
required ‘southern’ educational requirements
(Ford et al., 2007). As young Inuit have
become more removed from traditional
hunting practices, the dangers of a lack of
hunting knowledge compounded with variable
weather conditions further increases risk for
Indigenous hunters.
Climate change is already impacting Peary
and Dolphin and Union caribou populations,
and their neighboring Indigenous
communities, and it is important to further
monitor how these changing weather patterns
and temperatures increase caribou
vulnerability to changing vegetation, increased
predation and parasitism. As caribou
populations become more threatened, so will
the subsequent Indigenous communities be
similarly vulnerable. Many of the climate
change impacts such as decreased food
availability and sea ice, increased extreme
weather and increased parasitism that harm
Arctic caribou populations will also hurt
Indigenous communities.
Thus, is important to include Indigenous
voices in climate dialogues, research and
policy-making. Indigenous peoples possess
knowledge about wildlife and caribou
populations that dates back to several
generations (Ferguson et al., 1998), and this
background can be extremely useful for
understanding past caribou population
fluctuations. The Inuit understanding of Arctic
ecosystems differs from scientific research
because the Indigenous communities are
collecting research that is geared around their
own survival, so they may be more in tune
with changes than a remote scientist would
(Ferguson et al., 1998). Northern Indigenous
caribou hunters have already noticed how
changing weather patterns, industrial
development in caribou habitat and increased
frequency of forest fires have led to a
deterioration of caribou body health and
migration patterns (Vors and Boyce, 2009).
Future research should also be done to explore
how caribou populations (and, subsequently,
Indigenous communities) are impacted by
other Arctic factors such as permafrost thaw
and thermokarsts. Other areas for more
research include a greater understanding of
parasites and other pathogenic threats to
Canadian High Arctic caribou populations and
their transference to nearby Indigenous
communities. Continually monitoring caribou
populations will also help researchers to better
understand how much this current decline is
impacted by climate change, or if it is more
related to typical population fluctuations.
While the predicted impacts of climate change
are varied and complex (Hulme, 2005 ;
Mallory and Boyce, 2017), this review
suggests that the overall effect on Canadian
Arctic caribou populations will be negative.

13. 12
Climate models suggest that extreme weather
events and other unfavorable conditions will
be more common in the future (Ford et al.,
2007 ; Tews et al., 2007), which will likely
significantly stress the caribou populations. It
is possible that the impacts of climate change
will shift over time, and that these population
declines are simply due to normal caribou
population fluctuations (Vors and Boyce,
2009 ; Mallory and Boyce, 2017). However,
the current predictions suggest that Peary
caribou populations may not be able to cope
with the additional environmental stresses,
and assuming that this current decline is
emblematic of past population fluctuations
could prevent governmental adaption and
mitigation measures from being taken (Miller
and Barry, 2009 ; Vors and Boyce, 2009). On
the species level, it is possible that caribou
populations will not be able to adapt at the
pace of current and predicted environmental
change (Mallory and Boyce, 2017).

14. 13
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