Geographic variation in caribou on the Canadian arctic islands

1982 ◽  
Vol 60 (10) ◽  
pp. 2442-2454 ◽  
Author(s):  
D. C. Thomas ◽  
P. Everson
Keyword(s):  
Geographic Variation ◽  
Rangifer Tarandus ◽  
Canadian Arctic ◽  
The Other ◽  
Long Bones ◽  
Body Measurements ◽  
Morphological Similarity ◽  
North Central ◽  
Barren Ground ◽  
Northern Regions

Analyses of body, leg bone, skull, and pelage data indicated a cline in the characters of caribou (Rangifer tarandus) from central Boothia Peninsula to the western Queen Elizabeth Islands. The main difference between the skulls of barren-ground caribou (R. t. groenlandicus) on central Boothia Peninsula and the more northerly Peary caribou (R. t. pearyi) was a shorter muzzle in the latter. Pelage tone was markedly lighter in Peary caribou and they were smaller in most body measurements, most notably in the length of long bones. Two major populations of Peary caribou were identified: one on the western Queen Elizabeth Islands (Parry Islands), the other on Somerset and Prince of Wales islands. Differences in skull size and form suggest that each population was composed of two or more subpopulations. The larger and darker R. t. groenlandicus occurred on north-central Boothia Peninsula and the two subspecies and apparent intergrades were present in winter on northern regions of the peninsula. The morphological similarity of Peary caribou on Somerset and Prince of Wales islands is explained by interisland movements resulting in genetic mixing. The same is true for caribou on the western Queen Elizabeth Islands and that population apparently has little genetic interchange with the other.

Morphological variation and systematics of Dipsas catesbyi (Sentzen, 1796) and Dipsas pavonina Schlegel, 1837 (Serpentes: Dipsadinae)

Zootaxa ◽  
2009 ◽  
Vol 2203 (1) ◽  
pp. 31-48 ◽  
Author(s):  
ANA CAROLINE DE LIMA ◽  
ANA LÚCIA DA COSTA PRUDENTE
Keyword(s):  
South America ◽  
Geographic Variation ◽  
Geographic Distribution ◽  
Morphological Variation ◽  
Color Pattern ◽  
High Variability ◽  
The Other ◽  
Morphological Similarity ◽  
Morphometric Characters ◽  
Morphological Studies

The genus Dipsas includes approximately 32 species, distributed from Mexico to South America (Brazil, Argentina, Paraguay, Bolivia and Peru). High variability in color pattern and scalation has made it difficult to define limits among Dipsas species and to interpret patterns of geographic variation. We analyzed 14 meristic and 18 morphometric characters of 483 specimens of D. catesbyi and 129 specimens of D. pavonina, as well as their color pattern, coloration, hemipenis, cephalic glands and geographic distribution. We describe variation in meristic and morphometric characters and incorporate new characters into revised diagnoses. The results indicate a greater morphological similarity between D. catesbyi and species of Sibynomorphus than with the other species of Dipsas. More morphological studies should be done to evaluate current phylogenetic proposals for relationships within the tribe Dipsadini.

scholarly journals The late winter diets of barren-ground caribou in North-Central Canada

Rangifer ◽  
1986 ◽  
Vol 6 (2) ◽  
pp. 305 ◽  
Author(s):  
Donald C. Thomas ◽  
David P. Hervieux
Keyword(s):  
Rangifer Tarandus ◽  
Late Winter ◽  
North Central ◽  
Winter Range ◽  
Barren Ground ◽  
South Central ◽  
Conifer Needles ◽  
Central Canada ◽  
Winter Diets ◽  
Composite Samples

Rumen samples from 104 barren-ground caribou (Rangifer tarandus groenlandicus) collected in March 1980 and 1981 at 18 sites on the winter range in south-central Northwest Territories (NWT) and northern Saskatchewan were examined microscopically for relative occurrence of plant fragments. The composition of plant fragments in the rumens of calves did not differ from that in older caribou. Samples were homogeneous within sites and among them. Therefore we analyzed composite samples for each site and then pooled the data. Terricolous fruticose and foliose lichens averaged 68.5 ± 1.5% (SE) ot tallied fragments at all 18 sites, followed by conifer needles (11.9 ± 1.2%), green leaves of Vactinium spp., Ledum spp., and other shrubs and iorbs (5.6 ± 0.6%), twigs and bark (5.5 ± 0.4%), bryophytes (4.9 ± 0.6%) and 3.6% unidentified. The lichen component consisted of 8.4 ± 1.5% Stereocaulon spp., 46.9 ± 2.6% other fruticose lichens (largely Cladina spp., Cladonia spp., and Cetraria spp.), and 13.2 ± 1.5% foliose lichens (largely Peltigera spp.). A comparison of rumen contents with the average relative abundance of plants found in feeding craters at 13 sites suggests that use of plant species was not always proportionate to their occurrence.

Surplus killing as exemplified by wolf predation on newborn caribou

1985 ◽  
Vol 63 (2) ◽  
pp. 295-300 ◽  
Author(s):  
Frank L. Miller ◽  
Anne Gunn ◽  
Eric Broughton
Keyword(s):  
Northwest Territories ◽  
Canis Lupus ◽  
Rangifer Tarandus ◽  
The Other ◽  
Wolf Predation ◽  
Barren Ground ◽  
Rangifer Tarandus Groenlandicus

We searched for newborn calf carcasses of migratory barren-ground caribou (Rangifer tarandus groenlandicus) in June 1982 in the Northwest Territories. On 17 June, we found 34 calves killed by wolves (Canis lupus), clumped in a 3-km2 area. The calves had been killed apparently within minutes of each other and about 24 h before being found. Wolves had not fed on 17 of the carcasses and had only partially eaten the other 17. Ground observations illustrate the speed of and efficiency with which wolves can kill calves: a single wolf killed three calves on one occasion and three and possibly four calves on a second occasion at average kill rates of 1 calf/min, and 1 calf/8 min or 1 calf/6 min between the first and last deaths. We attributed the surplus killing of newborn caribou calves to their high densities and their vulnerability on the calving grounds. We recommend that a distinction be made between "surplus killing" and "excessive killing" by predators.

scholarly journals Warble infestations in some Canadian caribou and their significance

Rangifer ◽  
1990 ◽  
Vol 10 (3) ◽  
pp. 409 ◽  
Author(s):  
Donald D. Thomas ◽  
Hendrick P. L. Kiliaan
Keyword(s):  
Rangifer Tarandus ◽  
Canadian Arctic ◽  
Age Classes ◽  
Poor Condition ◽  
Barren Ground ◽  
Fly Larvae ◽  
Two Populations

Warble fly larvae (Oedemagena tarandi) occurred in 97-100% of barren-ground caribou (R.t. groen-landicus) sampled in March from the Beverly herd. In December, they occurred in 98% of males and 75% of females. Larvae numbers increased up to several-fold from December to March. Within age classes, males generally were more heavily infected than females. Annual differences were small. Larvae occurred in 14 and 26% of two populations of Peary caribou (Rangifer tarandus pearyi) on the Canadian Arctic Islands. In them, incidences of larvae were unrelated to sex or age. Greater than average numbers of larvae in barren-ground caribou sometimes were associated with females in relatively poor condition and therefore less fecund. These results are discussed in relation to current hypotheses of the factors that affect warble infections.

scholarly journals A life table for female barren-ground caribou in north-central Canada

Rangifer ◽  
1990 ◽  
Vol 10 (3) ◽  
pp. 177 ◽  
Author(s):  
Donald C. Thomas ◽  
Samuel J. Barry
Keyword(s):  
Life Table ◽  
Rangifer Tarandus ◽  
Sampling Error ◽  
Sampling Period ◽  
Cohort Size ◽  
North Central ◽  
Pooled Data ◽  
Barren Ground ◽  
Average Survival ◽  
Central Canada

A survivorship curve and cohort-specific life table were developed for female barren-ground caribou (Rangifer tarandus groenlandicus) sampled from the Beverly herd from 1980 through 1987. Significant (P~< 0.05)differences among yearly samples in the age distributions of females>2.5 years old were attributed to sampling error and real cohort size fluctuations caused by variations in productivity. Pooled data overcame much of that variation and the resultant quadratic-fit curve and life table are believed to yield about average survival/mortality statistics over the 8-year sampling period. Mortality rates increased progressively from 10.6% between age 2 and 3 years to 22.4% between age 10 and 11 years and accelerated thereafter.

Stromatoporoids from the Famennian (Devonian) Wabamun Formation, Normandville oilfield, north–central Alberta, Canada

1988 ◽  
Vol 62 (03) ◽  
pp. 411-419 ◽  
Author(s):  
Colin W. Stearn
Keyword(s):  
Patch Reef ◽  
Abundant Species ◽  
The Other ◽  
North Central ◽  
Biotic Crisis

Stromatoporoids are the principal framebuilding organisms in the patch reef that is part of the reservoir of the Normandville field. The reef is 10 m thick and 1.5 km2in area and demonstrates that stromatoporoids retained their ability to build reefal edifices into Famennian time despite the biotic crisis at the close of Frasnian time. The fauna is dominated by labechiids but includes three non-labechiid species. The most abundant species isStylostroma sinense(Dong) butLabechia palliseriStearn is also common. Both these species are highly variable and are described in terms of multiple phases that occur in a single skeleton. The other species described areClathrostromacf.C. jukkenseYavorsky,Gerronostromasp. (a columnar species), andStromatoporasp. The fauna belongs in Famennian/Strunian assemblage 2 as defined by Stearn et al. (1988).

MEASUREMENTS OF GRAVITY IN THE CANADIAN ARCTIC AND GREENLAND

1950 ◽  
Vol 28a (5) ◽  
pp. 535-541
Author(s):  
Michael Beer
Keyword(s):  
Canadian Arctic ◽  
Reference Points ◽  
The Other ◽  
Baffin Island ◽  
Resolute Bay ◽  
Future Work ◽  
Cornwallis Island

Four determinations of gravity were made during the summer of 1948, with the pendulum apparatus of the Dominion Observatory, at Goose Bay, Labrador (latitude 53°), Frobisher Bay, Baffin Island (latitude 64°), Resolute Bay, Cornwallis Island (latitude 75°), and Thule, Greenland (latitude 77°), approximately. The anomalies at the two most northerly stations are comparatively small and those at the other two stations, although larger, do not exceed many that have been observed in other parts of Canada. Norgaard's determination at Thule is confirmed by the author.It is anticipated that these determinations, apart from their immediate interest, will serve as useful reference points for future work in the Canadian Arctic.

Explorer without a country: the question of Vilhjalmur Stefansson's citizenship

Polar Record ◽  
2009 ◽  
Vol 45 (3) ◽  
pp. 237-241
Author(s):  
Janice Cavell ◽  
Jeff Noakes
Keyword(s):  
United States ◽  
Canadian Arctic ◽  
The United States ◽  
The Other ◽  
Dual Citizenship ◽  
American Citizen ◽  
American Citizenship ◽  
The Subject ◽  
The Government

ABSTRACTConfusion has long existed on the subject of Vilhjalmur Stefansson's citizenship. A Canadian (that is, a British subject) by birth, Stefansson was brought up and educated in the United States. When his father became an American citizen in 1887, according to the laws of the time Stefansson too became an American. Dual citizenship was not then permitted by either the British or the American laws. Therefore, Stefansson was no longer a British subject. After he took command of the government sponsored Canadian Arctic Expedition in 1913, Stefansson was careful to give the impression that his status had never changed. Although Stefansson swore an oath of allegiance to King George V in May 1913, he did not take the other steps that would have been required to restore him to being Canadian. But, by an American act passed in 1907, this oath meant the loss of Stefansson's American citizenship. In the 1930s American officials informed Stefansson that he must apply for naturalisation in order to regain it. From 1913 until he received his American citizenship papers in 1937, Stefansson was a man without a country.

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