scholarly journals Apparent Collapse of the Peary Caribou (Rangifer tarandus pearyi) Population on Axel Heiberg Island, Nunavut, Canada

ARCTIC ◽  
2020 ◽  
Vol 73 (4) ◽  
pp. 499-508
Author(s):  
Conor D. Mallory ◽  
Matthew Fredlund ◽  
Mitch W. Campbell

  In spring 2019, we conducted a comprehensive abundance and distribution survey for Peary caribou (Rangifer tarandus pearyi) and muskox (Ovibos moschatus) on Axel Heiberg Island, Nunavut, Canada. Although much of Axel Heiberg Island is rugged and extensively glaciated, areas east of the Princess Margaret mountain range have high productivity given the latitude and have supported relatively large numbers of Peary caribou and muskoxen. This region of the island has been previously identified as a potential High Arctic refugium. The last island-wide survey, in 2007, estimated 4237 muskoxen (95% confidence interval [CI] [3371:5325]) and 2291 Peary caribou (95% CI [1636:3208]); based on our 2019 results, it appears that muskox numbers have been stable on Axel Heiberg Island since then. Using distance sampling and density surface models, we estimated 3772 muskoxen (95% CI [3001:4742]) on Axel Heiberg Island during our 2019 survey. In contrast, Peary caribou, which is listed as an endangered species under the Canadian Species at Risk Act, appear to have declined dramatically from the 2007 estimate. During the 2019 survey, we observed only six Peary caribou and could not generate an island-wide estimate. Abrupt declines in numbers are characteristic of the species and are usually related to poor winter conditions such as dense snowpack or extreme weather events that result in widespread ground-fast icing. However, the limited monitoring information available at the northern extent of Peary caribou range presents major challenges to our understanding of the mechanisms leading to this near total absence of approximately 20% of range-wide Peary caribou numbers.

2019 ◽  
Vol 11 (3) ◽  
pp. 56 ◽  
Author(s):  
Ramón A. Delanoy ◽  
Misael Díaz-Asencio ◽  
Rafael Méndez-Tejeda

The Bay of Samaná, formed by tectonism and sedimentation, is delimited to the north by the peninsula of the same name, to the south by the north slope of the Eastern Mountain Range and Los Haitises National Park, to the east by the Atlantic Ocean, and to the west by the ancient Gran Estero, today the Lower Yuna. There follows a process of continuous degradation by the existing tectonic forces and the sediment contributions by the Yuna, Yabón, and La Yeguada rivers to the south as well as by the landslides of the mountainous area of the Samaná Peninsula, during periods of storms and hurricanes. The coastal area of Samaná Bay has altered by 2.17 km2 at the mouth of the Yuna River from 2003–2015. The high turbidity level has affected coral reefs and marine species.  The  mangroves  are  lost  faster  than  they  are  regenerated  by  the  coastline’s change. Variations in the elemental compositions of calcium and iron show the terrigenous influence on the dynamics of the bay during Extreme Weather Events (EWP) in the river basins that flow into it. Abrupt changes in the rainfall regime produced an equal change in the estuary sedimentation regime, according to the 210Pb. In the 2007–2016 period, a column of sediment that reached 38 cm and a 12 cm to 8.4 km column were deposited 4 km southeast of the municipality of Sánchez and east of the mouth of the Yuna River. The Sedimentary Accumulation Rate is very high, and the content of heavy metals exceeds the threshold values of Table SQuirt.


Rangifer ◽  
2003 ◽  
Vol 23 (5) ◽  
pp. 213 ◽  
Author(s):  
Frank L. Miller ◽  
Anne Gunn

The Peary caribou (Rangifer tarandus pearyi) was recognized as 'Threatened' by the Committee on the Status of Endangered Wildlife in Canada in 1979 and 'Endangered' in 1991. It is the only member of the deer family (Cervidae) found on the Queen Elizabeth Islands (QEI) of the Canadian High Arctic. The Peary caribou is a significant part of the region's biodiversity and a socially important and economically valuable part of Arctic Canada's natural heritage. Recent microsatellite DNA findings indicate that Peary caribou on the QEI are distinct from caribou on the other Arctic Islands beyond the QEI, including Banks Island. This fact must be kept in mind if any translocation of caribou to the QEI is proposed. The subspecies is too gross a level at which to recognize the considerable diversity that exists between Peary caribou on the QEI and divergent caribou on other Canadian Arctic Islands. The Committee on the Status of Endangered Wildlife in Canada should take this considerable diversity among these caribou at below the subspecies classification to mind when assigning conservation divisions (units) to caribou on the Canadian Arctic Islands. In summer 1961, the first and only nearly range-wide aerial survey of Peary caribou yielded a population estimate on the QEI of 25 845, including about 20% calves. There was a strong preference for range on the western QEI (WEQI), where 94% (24 363) of the estimated caribou occurred on only 24% (ca. 97 000 km2) of the collective island-landmass. By summer 1973, the overall number of Peary caribou on the QEI had decreased markedly and was estimated at about 7000 animals. The following winter and spring (1973-74), the Peary caribou population declined 49% on the WQEI. The estimated number dropping to <3000, with no calves seen by us in summer 1974. Based on estimates from several aerial surveys conducted on the WQEI from 1985 to 1987, the number of Peary caribou on the QEI as a whole was judged to be 3300-3600 or only about 13-14% of the 1961 estimate. After a partial recovery in the late 1980s and early 1990s, Peary caribou on the WQEI declined drastically between 1994 and 1997 and were estimated at an all-time known low of about 1100 animals by summer 1997. The number of Peary caribou on the QEI in summer 1997 was likely no more than 2000-2400 or only 8-9% of the 1961 estimate. The four known major die-offs of Peary caribou on the WQEI between 1973 and 1997 occurred during winter and spring periods (1 Sep-21 Jun) with significantly greater (P<0.005) total snowfall, when compared to the long-term mean obtained from 55 caribou-years (1 Jul-30 Jun), 1947/48-2001/02, of weather records from Resolute Airport on Cornwallis Island. Of ecological significance is that the die-offs occurred when the caribou were at low mean overall densities and involved similar high annual rates of loss among muskoxen (Ovibos moschatus). All of the available evidence indicates that Peary caribou (and muskoxen) on the QEI experienced die-offs from prolonged, under-nutrition (starvation) caused by relative unavailability of forage-the forage was there but it was inaccessible to the caribou due to snow and/or ice cover. We cannot control the severe weather that greatly restricts the forage supply but we should try to reduce the losses of Peary caribou from other sources-humans, predators and competitors.


Ecosphere ◽  
2016 ◽  
Vol 7 (6) ◽  
Author(s):  
Leif Egil Loe ◽  
Brage B. Hansen ◽  
Audun Stien ◽  
Steve D. Albon ◽  
Richard Bischof ◽  
...  

Rangifer ◽  
1996 ◽  
Vol 16 (2) ◽  
pp. 51 ◽  
Author(s):  
David R. Klein

The two ungulate species that occur in the High Arctic, Rangifer tarandus and Ovibos moschatus, exhibit considerable adaptive plasticity in response to habitat variability throughout their circumpolar distribution. R. tarandus, however, has a much wider latitudinal distribution and occurs within a wider range of both forest and tundra habitat types than 0. moschatus, reflecting greater morphological, physiological, and behavioral plasticity. As a consequence, muskoxen have been less successful than caribou and reindeer in maintaining populations at their southern limits. Muskoxen, however, existed throughout Pleistocene glaciations in the cold periglacial steppes of Eurasia and North America and find the closest analog to this vegetation type in the High Arctic, where they have been more successful than R. tarandus in maintaining their populations.


2019 ◽  
Vol 53 (5) ◽  
pp. 399-416
Author(s):  
V. M. Tytar ◽  
Ya. R. Oksentyuk

Abstract In this study an attempt is made to highlight important variables shaping the current bioclimatic niche of a number of mite species associated with the infestation of stored products by employing a species distribution modeling (SDM) approach. Using the ENVIREM dataset of bioclimatic variables, performance of the most robust models was mostly influenced by: 1) indices based on potential evapotranspiration, which characterize ambient energy and are mostly correlated with temperature variables, moisture regimes, and 2) strong fluctuations in temperature reflecting the severity of climate and/or extreme weather events. Although the considered mite species occupy man-made ecosystems, they remain more or less affected by the surrounding bioclimatic environment and therefore could be subjected to contemporary climate change. In this respect investigations are needed to see how this will affect future management targets concerning the safety of food storages.


Author(s):  
I. Zolnikov ◽  
◽  
A. Vybornov ◽  
A. Anoikin ◽  
A. Postnov ◽  
...  

In the course of studies conducted by IAET SB RAS in the Lower Ob in 2016–2019, the understanding of the conditions for settlement of the Paleolithic population in the north of Western Siberia was significantly supplemented. Dating of a series of paleontological finds was carried out at the "Accelerated mass spectrometer of the Budker Institute of Nucle- ar Physics of SB RAS". The dates obtained show the distribution of the main representatives of the Upper Pleistocene fauna of Subarctica: Mammuthus primigenius – 50,000–15,000 BP, Coelodonta antiquitatis – 43,000–38,000 BP and 27,000–25,000 BP, Rangifer tarandus, Equus ferus – 40,000–10,000 BP, Bison sp. – 50,000–40,000 BP, Ovibos moschatus – 41,000–32,000 BP.


Author(s):  
Sergio A. Molina Murillo

Most scenarios indicate that people in developing countries are more vulnerable and less capable of adapting to climate change. Since our public understanding of risk toward climate change in developing countries is limited, this article presents results from Costa Rica and Nicaragua, two countries which are socio-economically distinct, but which are expected to suffer similar extreme weather events. From October of 2008 until May 2010, a total of 1,047 respondents were surveyed in cities of both countries. The main results indicate that climate change is a widely known concept but other notions such as “carbon footprint” are foreign to most respondents. Despite the general concern with its negative consequences, respondents’ foremost concern is linked to their socioeconomic situation, and how it will be impacted by climate change in such aspects as poverty and social security. The results presented here contribute to advance national and international policies aiming to support mitigation or adaptation strategies in developing countries.


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