Prevalence of Toxoplasma gondii Antibodies in Barren-Ground Caribou (Rangifer tarandus groenlandicus) from the Canadian Arctic

2001 ◽  
Vol 87 (2) ◽  
pp. 439 ◽  
Author(s):  
S. J. Kutz ◽  
B. T. Elkin ◽  
D. Panayi ◽  
J. P. Dubey
Keyword(s):  
Toxoplasma Gondii ◽  
Rangifer Tarandus ◽  
Canadian Arctic ◽  
Barren Ground ◽  
Rangifer Tarandus Groenlandicus

scholarly journals Age-specific fecundity of the Beverly herd of barren-ground caribou

Rangifer ◽  
1990 ◽  
Vol 10 (3) ◽  
pp. 257 ◽  
Author(s):  
Donald C. Thomas ◽  
Samuel J. Barry
Keyword(s):  
Rangifer Tarandus ◽  
Barren Ground ◽  
Rangifer Tarandus Groenlandicus

The age-specific fecundity of the Beverly herd of barren-ground caribou (Rangifer tarandus groenlandicus) was monitored each winter from 1979-80 through 1986-87. Fecundity in 840 females increased with age from 12% in yearlings to 86% at age 5 years and it did not decline in old (> 11 yr) females. Significant variations occurred among winters and even between two subherds in one winter. Reproductive abnormalities were detected in 2 of 840 females and a probable resorption in 1 of 420 females collected in March. Only about 5% of the fetuses were conceived late, possibly by repeat ovulators. Combining survival and fecundity data yielded age-specific calf production, which indicated that, for example, 54% of calves were born to females 3-6 years old.

Morphology of the barren-ground caribou ovary

1978 ◽  
Vol 56 (8) ◽  
pp. 1684-1696 ◽  
Author(s):  
T. Charles Dauphiné Jr.
Keyword(s):  
Connective Tissue ◽  
Rangifer Tarandus ◽  
Corpora Lutea ◽  
Seasonal Incidence ◽  
Histological Techniques ◽  
Northern Canada ◽  
Ovary Weight ◽  
Barren Ground ◽  
Ovarian Stroma ◽  
Rangifer Tarandus Groenlandicus

Reproductive tracts were collected from 532 female caribou (Rangifer tarandus groenlandicus) in northern Canada over a [Formula: see text]-year period. Ovaries were weighed and scrutinized by gross and histological techniques. Ovaries of nulliparous and nongravid, parous cows responded to follicular fluctuations by increasing in weight in summer and declining in winter. Weights of ovaries from calves, yearlings, and 2 year olds overlapped extensively. Formation of corpora lutea of pregnancy more than doubled ovary weight. During gestation ovary weight declined and then partially recovered; it increased with age in pregnant cows. The number and size of follicles [Formula: see text] diameter increased with age until puberty, reaching greatest development just before the autumn rut. After puberty the seasonal incidence of such follicles remained stable except during gestation, when it declined. Corpora lutea of pregnancy regressed to form apparently permanent scars composed of vascular and connective tissue remnants. Secondary corpora lutea developed in 35% of the cows at or before conception and upon regression produced scars which were not permanent. Regressing corpora lutea of estrus also disappeared into the ovarian stroma, apparently within 1 year. In individual cows one ovary, selected at random, dominated in the production of ova and corpora lutea.

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.

scholarly journals Genetic diversity, structure and gene flow of migratory barren-ground caribou (Rangifer tarandus groenlandicus) in Canada

Rangifer ◽  
2016 ◽  
Vol 36 (1) ◽  
pp. 1 ◽  
Author(s):  
Keri McFarlane ◽  
Anne Gunn ◽  
Mitch Campbell ◽  
Mathieu Dumond ◽  
Jan Adamczewski ◽  
...  
Keyword(s):  
Genetic Diversity ◽  
Genetic Variation ◽  
Gene Flow ◽  
Rangifer Tarandus ◽  
Continuous Distribution ◽  
Effective Population ◽  
Genetic Population ◽  
Barren Ground ◽  
Cyclic Changes ◽  
Rangifer Tarandus Groenlandicus

Migratory barren-ground caribou (Rangifer tarandus groenlandicus) provide an opportunity to examine the genetic population structure of a migratory large mammal whose movements and distribution, in some instances, have not been heavily influenced by human activities that result in habitat loss or fragmentation. These caribou have likely reached large effective population sizes since their rapid radiation during the early Holocene despite cyclic changes in abundance. Migratory barren-ground caribou are managed as discrete subpopulations. We investigated genetic variation among those subpopulations to determine the patterns of genetic diversity within and among them, and the implications for long-term persistence of caribou. We identified three distinct genetic clusters across the Canadian arctic tundra: the first cluster consisted of all fully-continental migratory barren-ground subpopulations; the second cluster was the Dolphin and Union caribou; and the third cluster was caribou from Southampton Island. The Southampton Island caribou are especially genetically distinct from the other barren-ground type caribou. Gene flow among subpopulations varied across the range. Occasional gene flow across the sea-ice is likely the reason for high levels of genetic variation in the Dolphin and Union subpopulation, which experienced very low numbers in the past. These results suggest that for most migratory caribou subpopulations, connectivity among subpopulations plays an important role in maintaining natural genetic diversity. Our analyses provide insight into the levels of microsatellite genetic diversity and patterns of gene flow that may be common to large subpopulations that historically had a continuous distribution across a large continental range. These data can also be used as a benchmark to compare the effects of habitat fragmentation and bottlenecks on other large caribou populations.

scholarly journals What Happened to the Beverly Caribou Herd after 1994?

ARCTIC ◽  
2015 ◽  
Vol 68 (4) ◽  
pp. 407 ◽  
Author(s):  
Jan Adamczewski ◽  
Anne Gunn ◽  
Kim G. Poole ◽  
Alexander Hall ◽  
John Nishi ◽  
...  
Keyword(s):  
Rangifer Tarandus ◽  
Alternative Explanation ◽  
Herd Size ◽  
Barren Ground ◽  
Management Actions ◽  
The North ◽  
Large Size ◽  
Ground Survey ◽  
Newborn Calves ◽  
Rangifer Tarandus Groenlandicus

The Beverly herd was one of the first large migratory herds of barren-ground caribou (Rangifer tarandus groenlandicus) defined in northern Canada on the basis of annual return of breeding females to traditional calving grounds near Beverly Lake in Nunavut. In 1994, herd size was estimated at 276 000 ± 106 600 (SE) adult caribou, but monitoring was minimal from 1994 to 2007. The next calving ground survey in 2002 revealed that caribou densities had dropped by more than half since 1994; annual surveys following from 2007 to 2009 demonstrated an extreme decline in numbers of calving cows, and by 2011, no newborn calves were seen there. We examine two possible explanations for the declining use of the traditional Beverly calving grounds from 1994 until their abandonment by 2011. One explanation is that a true numerical decline in herd size occurred, driven in at least the later stages by low cow survival and poor calf productivity, which led the remaining Beverly cows to switch to the neighbouring Ahiak calving ground 250 km to the north in 2007 – 09 and join that herd. An alternative explanation is that the decline on the traditional Beverly calving grounds was largely due to a distributional shift to the north of the Beverly herd that may have begun in the mid-1990s. We suggest that the former explanation is the more likely and that the Beverly herd no longer exists as a distinct herd. We acknowledge that gaps in monitoring of Beverly and Ahiak caribou hamper definitive evaluation of the Beverly herd’s fate. The large size sometimes achieved by barren-ground caribou herds is not a guarantee of persistence; monitoring shortfalls may hamper management actions to address declines.

Brucellosis in reindeer, Rangifer tarandus L., and the migratory barren-ground caribou, Rangifer tarandus groenlandicus (L.), in Canada

1970 ◽  
Vol 48 (5) ◽  
pp. 1023-1027 ◽  
Author(s):  
E. Broughton ◽  
L. P. E. Choquette ◽  
J. G. Cousineau ◽  
F. L. Miller
Keyword(s):  
Public Health ◽  
Positive Reaction ◽  
Rangifer Tarandus ◽  
River Delta ◽  
Serum Samples ◽  
Barren Ground ◽  
Animal Populations ◽  
Sexually Mature ◽  
Rangifer Tarandus Groenlandicus ◽  
Mackenzie River

Serum samples from 1692 reindeer slaughtered in the Mackenzie River Delta in the last decade and from 320 Kaminuriak barren-ground caribou killed between June 1966 and July 1968 were tested for brucellosis. All sera yielding titers of 1:25 or higher were considered to be positive. A positive reaction was obtained in 148 of the 1692 reindeer and 14 of the 320 barren-ground caribou tested, giving an overall reactor percentage of 8.74 in reindeer and 4.37 in caribou.Orchitis, epididymitis, bursitis, metritis, abortion, and placental retention—conditions associated with brucellosis in reindeer in the U.S.S.R. and caribou in Alaska—were not noted in the autopsy of the 1692 reindeer and of 500 sexually mature barren-ground caribou. Three possible records of bursitis, of unknown nature, in barren-ground caribou are discussed. Seemingly, brucellosis does not represent a serious threat to either the Mackenzie River Delta reindeer or the Kaminuriak barren-ground caribou population, but its detection in these animal populations is of interest from a public health standpoint.

Sign in / Sign up

Export Citation Format

Share Document