scholarly journals Fire - caribou - winter range relationships in northern Canada

Rangifer ◽  
1996 ◽  
Vol 16 (2) ◽  
pp. 57 ◽  
Author(s):  
D.C. Thomas ◽  
S.J. Barry ◽  
G. Alaie
Keyword(s):  
Rangifer Tarandus ◽  
Fire Suppression ◽  
Age Classes ◽  
The West ◽  
North Central ◽  
Winter Range ◽  
Peak Biomass ◽  
Central Canada ◽  
Cladina Rangiferina ◽  
Terrestrial Lichen

We needed data on temporal changes in caribou forages after fire and relative use of age-classes of forests by caribou to help devise a fire suppression priority strategy for caribou winter range in north-central Canada. Consequently, from 1983 through 1986, we estimated the abundance of vegetation and relative use by caribou at 197 sites in western and eastern study areas on the winter range of the Beverly herd of caribou {Rangifer tarandus). Species of lichens attained peak biomass at different periods after fire - as early as 40-60 years for Cladonia spp. to > 150 years for Cladina rangiferina and Cetraria nivalis. Biomass of the primary "caribou lichen", Cladina mitis, increased rapidly from 21-30 years after fire to 41-50 years and attained maximum biomass at 81-90 yeats in the west and 41-60 years in the east. However, total lichen biomass increased with age of forest to 100-150 years because biomass of Stereocaulon spp. did not peak until after 100 years. The biomass of "caribou lichens" {Cladina spp. and Cetraria nivalis) stabilized after 61-80 years in the west and 41-60 years in the east. The biomass of terrestrial lichen species can be predicted from their cover. Caribou lichen abundance apparently was only one of several factors that caused caribou to use stands 151-250 years after fire more than othet age classes.

scholarly journals A fire suppression model for forested range of the Beverly and Qamanirjuaq herds of caribou

Rangifer ◽  
1996 ◽  
Vol 16 (4) ◽  
pp. 343
Author(s):  
Donald C. Thomas ◽  
The Beverly and Qamanirjuaq Caribou Management Board
Keyword(s):  
Rangifer Tarandus ◽  
Aboriginal People ◽  
Fire Suppression ◽  
Specific Area ◽  
Fire Cycle ◽  
Management Board ◽  
Winter Range ◽  
Natural Fires ◽  
Central Canada ◽  
Cycle Lengths

A fire suppression model was developed for forested winter range of the Beverly and Qamanirjuaq (formerly Kaminuriak) herds of barren-ground caribou (Rangifer tarandus groenlandicus) in north-central Canada. The model is a balance between total protection, as voiced by some aboriginal people, and a let-burn policy for natural fires advocated by some ecologists. Elements in the model were caribou ecology, lichen recovery after fire, burn history, community priorities for caribou hunting, and fire cycle lengths. The percent ratio of current productive caribou habitat to the goal for that habitat determines whether fire should be suppressed in a specific area. The goals for productive caribou habitat, defined as forests older than 50 years, were scaled by fire cycle length and community priority ranking. Thus, the model is an example of co-management: traditional knowledge combined with science in a joint forum, the Beverly and Qamanirjuaq Caribou Management Board.

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.

scholarly journals Feeding site selection by woodland caribou in north-central British Columbia

Rangifer ◽  
2000 ◽  
Vol 20 (5) ◽  
pp. 158 ◽  
Author(s):  
Chris J. Johnson ◽  
Katherine L. Parker ◽  
Douglas C. Heard
Keyword(s):  
British Columbia ◽  
Rangifer Tarandus ◽  
Lower Percentage ◽  
Percent Cover ◽  
Woodland Caribou ◽  
North Central ◽  
Feeding Site ◽  
Feeding Sites ◽  
Cladina Rangiferina ◽  
The Individual

We examined the foraging habits of the northern woodland caribou ecotype {Rangifer tarandus caribou) at the scale of the individual feeding site. Field data were collected in north-central British Columbia over two winters (Dec 1996-Apr 1998). We trailed caribou and measured vegetation characteristics (species composition and percent cover), snow conditions (depth, density, and hardness), and canopy closure at terrestrial and arboreal feeding sites, and at random sites where feeding had not occurred. Logistic regression was used to determine the attributes of feeding sites that were important to predicting fine scale habitat selection in forested and alpine areas. In the forest, caribou selected feeding sites that had a greater percent cover of Cladina mitis and Cladonia spp, lower snow depths, and a lower percentage of debris and moss. Biomass of Bryoria spp. at the 1-2 m stratum above the snow significantly contributed to predicting what trees caribou chose as arboreal feeding sites. In the alpine, caribou selected feeding sites with a greater percent cover of Cladina mitis, Cladina rangiferina, Cetraria cucullata, Cetraria nivalis, Thamnolia spp., and Stereocaulon alpinum as well as lower snow depths.

scholarly journals Prevalence of Echinococcus granulosus and Taenia hydatigena in caribou in north-central Canada

Rangifer ◽  
1996 ◽  
Vol 16 (4) ◽  
pp. 331 ◽  
Author(s):  
Donald C. Thomas
Keyword(s):  
Echinococcus Granulosus ◽  
Rangifer Tarandus ◽  
Infection Intensity ◽  
Parasite Prevalence ◽  
Predation Rate ◽  
Older Individuals ◽  
Taenia Hydatigena ◽  
North Central ◽  
Central Canada ◽  
Few Data

There are few data on the prevalence and infection intensity of parasites in large samples of caribou (Rangifer tarandus). Therefore, differences related to sex, age, and season are unknown. The effect of parasites on the health and condition of caribou also is poorly known. From 1980 through 1987, 1258 barren-ground caribou (R.t. groenlandicus) were collected from the Beverly herd in north-central Canada. The prevalence in lungs of cysts of the hydatid tapeworm (Echinococcus granulosus) increased significantly with age of caribou. Prevalence in females was 2% in the 2-5 year class and 8% in older individuals. Cysts were more prevalent in young females compared with young males. Reductions in physical condition and fecundity were not statistically significant. The prevalence of Taenia hydatigena cysts in livers increased significantly with age of host but not with sex and condition of the hosts. The use of parasite prevalence as an index of predation rate is discussed.

scholarly journals Assessment of Alaska reindeer populations and range conditions

Rangifer ◽  
1992 ◽  
Vol 12 (1) ◽  
pp. 33 ◽  
Author(s):  
J. D. Swanson ◽  
M. H. W. Barker
Keyword(s):  
Bering Sea ◽  
Rangifer Tarandus ◽  
Alces Alces ◽  
Ecological Condition ◽  
Sea Islands ◽  
Ovibos Moschatus ◽  
Winter Range ◽  
Monitoring Programs ◽  
Cladina Rangiferina

Populations of reindeer (Rangifer tarandus) have fluctated greatly since their introduction to Alaska in 1891. In the 1930s, reported numbers exceeded 600 000. Presently, 38 000 reindeer graze 6.2 million ha of rangeland and woodland in Western Alaska (from 66°54'N to 52°07'N latitude). Condition of winter range producing fruticose lichens (Cladina rangiferina, Cladina arbuscula, Cladina stellaris, Cetraria cucullata, Cetraria islandica) is of major concern. Monitoring programs have been established for vegetation, fire, reindeer and wildlife. Reindeer have overgrazed lichen resources on some Bering Sea Islands. Wildfires have had the greatest impact on lichen range depletion on the mainland. Overgrazing has been a problem in localized areas. Moose (Alces alces) and muskox (Ovibos moschatus) rarely contribute to major lichen depletion. 60-80% of the mainland and 5-30% of most island winter lichen ranges are presently estimated to be in good to excellent ecological condition. Procedures for assessing condition of the lichen ranges are being further refined.

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.

PRE-BONNEVILLE LAKES IN CACHE VALLEY AND EXCAVATION OF CUTLER NARROWS ACROSS THE CACHE BUTTE DIVIDE IN THE WEST, NORTH-CENTRAL UTAH AND SOUTHEASTERN IDAHO

2020 ◽  
Author(s):  
Robert Q. Oaks ◽  
◽  
Susanne U. Janecke ◽  
Tammy M. Rittenour ◽  
Thad L. Erickson ◽  
...  
Keyword(s):  
The West ◽  
North Central ◽  
Cache Valley ◽  
West North Central

Abstract MP75: Geographic Variation in Stroke Rates and Oral Anticoagulation Use among Medicare Beneficiaries with Atrial Fibrillation

Circulation ◽  
2018 ◽  
Vol 137 (suppl_1) ◽  
Author(s):  
Inmaculada Hernandez ◽  
Samir Saba ◽  
Yuting Zhang
Keyword(s):  
Atrial Fibrillation ◽  
Ischemic Stroke ◽  
Geographic Variation ◽  
Newly Diagnosed ◽  
Medicare Beneficiaries ◽  
The West ◽  
North Central ◽  
Census Division ◽  
Adjusted Rate ◽  
West North Central

Background: Recent studies have shown strong geographic variation in oral anticoagulation (OAC) use in atrial fibrillation (AF); however, it remains unknown how this contributes to the geographic variation in ischemic stroke observed across the US. The objective of the present study was to evaluate the relationship between the geographic variation in the initiation of OAC and the incidence of ischemic stroke in a cohort of Medicare beneficiaries newly diagnosed with AF. Methods: Using 2013-2014 claims data from a 5% random sample of Medicare beneficiaries, we identified patients newly diagnosed with AF in 2013-2014 and categorized them according to their initiation of OAC. Our sample included 21,226 OAC initiators and 20,068 patients who did not initiate OAC therapy. We assigned each patient to one of the 9 US Census Divisions using the zip code, and collected their medical claims with a diagnosis of ischemic stroke. We constructed logistic regression models to estimate the average adjusted probability of OAC initiation and Poisson models to estimate the average adjusted rate of ischemic stroke, in each Census Division. Both estimates were adjusted for demographics, eligibility for Medicaid coverage and for low-income subsidy, enrollment in a Medicare Advantage Part D plan, and a comprehensive list of clinical characteristics. We computed the correlation between the average adjusted probability of OAC initiation and the average adjusted rate of ischemic stroke at the Census Division level. Results: The probability of OAC initiation was lowest in the West South Central (0.47) and highest in the West North Central (0.54) and New England (0.54). The average adjusted rate of ischemic stroke was lowest in the West North Central (0.09) and highest in the South Atlantic (0.14) and South West Central (0.14). The average adjusted probability of OAC initiation at the Census Division level and the average adjusted rate of ischemic stroke were inversely correlated, with R=-0.576, p-value=0.10. This suggests that variation in OAC initiation likely explains at least a third of geographic variation in ischemic stroke [R 2 =(-0.576) 2 =0.332]. Conclusions: Our results suggest that geographic variations in OAC initiation within the U.S. explain, in part, variations in the incidence of ischemic stroke among AF patients. Further mechanistic research using advanced causal mediation models is warranted.

PUBLIC HEALTH, NURSING AND MEDICAL SOCIAL WORK

PEDIATRICS ◽  
1948 ◽  
Vol 2 (1) ◽  
pp. 138-140
Keyword(s):  
Public Health ◽  
South Carolina ◽  
New England ◽  
The West ◽  
Central Section ◽  
North Central ◽  
South Central ◽  
High Incidence ◽  
Health Nursing ◽  
West North Central

THE accompanying table summarizes the incidence of nine important communicable diseases, based on weekly telegraphic reports from State health departments. The reports from each State for each week are published in PUBLIC HEALTH REPORTS under the section "Incidence of Disease." [See Table in Source Pdf]. Diseases Above Median Incidence Measles—The number of cases of measles rose from 102,680 during the preceding 4 weeks to 114,983 during the 4 weeks ended May 22. The incidence was 3.4 times the number of cases reported for the corresponding period in 1947, which was, however, a comparatively low measles year, but it was only about 10 percent above the 1943-47 median. In the New England and East South Central sections the incidence was below the normal expectancy and in the South Atlantic section the number of cases was only slightly higher than the median for the preceding 5 years, but in the other 6 sections the increases over the median expectancy ranged from 1.1 times the median in the West North Central section to 3.4 times the median in the West South Central section. Poliomyelitis.— The number of cases of poliomyelitis rose from 126 during the preceding 4-week period to 440 during the current 4 weeks. The incidence was 3.5 times that reported for these weeks in 1947, which number (126 cases) also represents the 1943-47 median. An increase of this disease is expected at this season of the year, but the current number of cases represents a larger increase at this time than has normally occurred in preceding years. While each section of the country except New England contributed to the relatively high incidence, the greatest excesses over the 5-year medians were reported from the West North Central and West South Central sections. Of the total cases Texas reported 179, California 62, South Carolina 46, New Jersey 16, Iowa 14, Florida 12, Alabama 11, and Illinois, South Dakota, and Louisiana 10 each; 85 percent of the reported cases occurred in those 10 states which represent every section of the country except the New England and Mountain sections. Since the beginning of the year there have been 947 cases of poliomyelitis reported as compared with 894 and 810 for the corresponding period in 1947 and 1946, respectively.

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