scholarly journals Status of woodland caribou in western north America

Rangifer ◽  
1991 ◽  
Vol 11 (4) ◽  
pp. 91 ◽  
Author(s):  
E. Janet Edmonds
Keyword(s):  
Land Use ◽  
North America ◽  
Rangifer Tarandus ◽  
Relative Distribution ◽  
Western North America ◽  
Woodland Caribou ◽  
Habitat Changes ◽  
Wide Range ◽  
Unknown Status ◽  
Management Approaches

A review of current population size and trends of woodland caribou (Rangifer tarandus caribou) in seven jurisdictions in western North America shows a wide range of situations. A total maximum population estimate of woodland caribou west of the Ontario/Manitoba border is 61 090. Of 44 herds or populations described in this review: 14 are stable; two are stable to slightly decreasing; four are decreasing; four are increasing; and 22 are of unknown status. Caribou are classified as a threatened species in Alberta and as an endangered species in Washington/Idaho. The decline of caribou in North America following settlement (Bergerud, 1974) has continued along the southern edge of woodland caribou distribution. Direct loss of habitat to logging, mines and dams continued throughout the I960s, 1970s and 1980s. The secondary effects of these habitat changes, (i.e. increased roads leading to increased hunting and poaching, and increased early succession habitat leading to increased alternate prey/predator densities) has led in some cases to the total loss or decreased size of local herds. Three ecotypes of woodland caribou are described and their relative distribution delineated. These ecotypes live under different environmental conditions and require different inventory and management approaches. Woodland caribou herds in northern B.C., Yukon and N.W.T. generally are of good numbers and viable (stable or increasing), and management primarily is directed at regulating human harvest and natural predation to prevent, herd declines. Land use activities such as logging or energy development are not extensive. Managers in southern caribou ranges stress the need for a better understanding of caribou population stability within mixed prey/predator regimes; how habitat changes (eg. through logging) affect these regimes; and how to develop effective land use guidelines for resource extraction that can sustian caribou populations and maintain resource industries. Caribou managers have suggested that herds may be priorized for research and management efforts. Unstable, remnant populations may be left to their own fate. The limited research dollars available and difficult management decisions should be applied to caribou herds that are apparently sustainable and provide the greatest potential for long-term viability.

scholarly journals Woodland caribou persistence and extirpation in relic populations on Lake Superior

Rangifer ◽  
2007 ◽  
Vol 27 (4) ◽  
pp. 57 ◽  
Author(s):  
Arthur T. Bergerud ◽  
W. J. Dalton ◽  
H. Butler ◽  
L. Camps ◽  
R. Ferguson
Keyword(s):  
North America ◽  
Rangifer Tarandus ◽  
Lake Superior ◽  
Continuous Distribution ◽  
Adult Survival ◽  
Late Winter ◽  
Woodland Caribou ◽  
Wolf Predation ◽  
The Mean ◽  
Crucial Test

Extended: The hypothesis was proposed that woodland caribou (Rangifer tarandus caribou) in North America had declined due to wolf predation and over-hunting rather than from a shortage of winter lichens (Bergerud, 1974). In 1974, two study areas were selected for testing: for the lichen hypothesis, we selected the Slate Islands in Lake Superior (36 km2), a closed canopy forest without terrestrial lichens, wolves, bears, or moose; for the predation hypothesis, we selected the nearby Pukaskwa National Park (PNP) where terrestrial lichens, wolves, bears, and moose were present. Both areas were monitored from 1974 to 2003 (30 years). The living and dead caribou on the Slates were estimated by the ‘King census’ strip transect (mean length 108±9.3 km, extremes 22-190, total 3026 km) and the Lincoln Index (mean tagged 45±3.6, extremes 15-78). The mean annual population on the Slate Islands based on the strip transects was 262±22 animals (extremes 104-606), or 7.3/km2 (29 years) and from the Lincoln Index 303±64 (extremes 181-482), or 8.4/km2 (23 years). These are the highest densities in North America and have persisted at least since 1949 (56 years). Mountain maple (Acer spicatum) interacted with caribou density creating a record in its age structure which corroborates persistence at relatively high density from c. 1930. The mean percentage of calves was 14.8±0.34% (20 years) in the fall and 14.1±1.95% (19 years) in late winter. The Slate Islands herd was regulated by the density dependent abundance of summer green foods and fall physical condition rather than density independent arboreal lichen availability and snow depths. Two wolves (1 wolf/150 caribou) crossed to the islands in 1993-94 and reduced two calf cohorts (3 and 4.9 per cent calves) while female adult survival declined from a mean of 82% to 71% and the population declined ≈100 animals. In PNP, caribou/moose/wolf populations were estimated by aerial surveys (in some years assisted by telemetry). The caribou population estimates ranged from 31 in 1979 to 9 in 2003 (Y=1267 - 0.628X, r=-0.783, n=21, P<0.01) and extirpation is forecast in 2018. Animals lived within 3 km of Lake Superior (Bergerud, 1985) with an original density of 0.06/km2, similar to many other woodland herds coexisting with wolves (Bergerud, 1992), and 100 times less than the density found on the Slate Islands. The mean moose population was 0.25±0.016/km2 and the wolf population averaged 8.5±0.65/1000 km2. Late winter calf percentages in PNP averaged 16.2±1.89 (25 years); the population was gradually reduced by winter wolf predation (Bergerud, 1989; 1996). The refuge habitat available is apparently insufficient for persistence in an area where the continuous distribution of woodland caribou is fragmented due to moose exceeding 0.10/km2 and thereby supporting wolf densities ≥6.5/1000 km2. A second experimental study was to introduce Slate Island caribou to areas with and without wolves. A release to Bowman Island, where wolves and moose were present, failed due to predation. Bowman Island is adjacent to St. Ignace Island where caribou had persisted into the late 1940s. A second release in 1989 to the mainland in Lake Superior Provincial Park of 39 animals has persisted (<10 animals) because the animals utilize off-shore islands but numbers are also declining. A third release to Montréal Island in 1984 doubled in numbers (up to 20 animals) until Lake Superior froze in 1994 and wolves reached the island. A fourth release was to Michipicoten Island (188 km2) in 1982 where wolves were absent and few lichens were available. This herd increased at λ= 1.18 (8 to ±200, 160 seen 2001) in 19 years. This was the island envisioned for the crucial test of the lichen/predation hypotheses (Bergerud, 1974: p.769). These studies strongly support the idea that ecosystems without predators are limited bottom–up by food and those with wolves top-down by predation; however the proposed crucial test which has been initiated on Michipicoten Island remains to be completed and there is a limited window of opportunity for unequivocal results.

Synlophe of Nematodirus odocoilei (Trichostrongyloidea) from deer and caribou in North America with comments on the evolution of Nematodirus spp. among the Cervidae (Artiodactyla)

1989 ◽  
Vol 67 (6) ◽  
pp. 1489-1494 ◽  
Author(s):  
Eric P. Hoberg ◽  
Michael Fruetel ◽  
Lora G. Rickard
Keyword(s):  
North America ◽  
Rangifer Tarandus ◽  
Odocoileus Hemionus ◽  
Cervical Region ◽  
Host Switching ◽  
Rangifer Tarandus Caribou ◽  
Woodland Caribou ◽  
Caudal Extremity ◽  
Males And Females ◽  
Host Parasite

The synlophe for specimens of Nematodirus odocoilei from deer (Odocoileus hemionus) and woodland caribou (Rangifer tarandus caribou) is characterized. In the cervical region, at the level of the cervical papillae, there are 36–42 and 38–47 ridges of variable height in males and females, respectively. Sixteen ridges extend to the cephalic expansion. In males, 34–40 ridges occur at midbody, and the synlophe extends posteriad to within 50 μm of the prebursal papillae. In females, 36–42 ridges occur at midbody; the maximum number of ridges occurs posterior to the vulva (50) with a decrease again posteriad. The synlophe is continuous and extends to the caudal extremity of females. Based on concepts of parasite–host biogeography, both host switching and coevolution appear as determinants in the relationships of Nematodirus spp. and cervids. An evaluation of parasite morphology and host–parasite biogeography suggests that in the plesiomorphic condition the synlophe is composed of a high number of ridges as exemplified by Nematodirus spp. from cervids and neotropical camelids.

scholarly journals The genomics of rapid climatic adaptation and parallel evolution in North American house mice

PLoS Genetics ◽  
2021 ◽  
Vol 17 (4) ◽  
pp. e1009495
Author(s):  
Kathleen G. Ferris ◽  
Andreas S. Chavez ◽  
Taichi A. Suzuki ◽  
Elizabeth J. Beckman ◽  
Megan Phifer-Rixey ◽  
...  
Keyword(s):  
Body Weight ◽  
North America ◽  
Genome Wide Association Study ◽  
Phenotypic Change ◽  
House Mice ◽  
Western North America ◽  
Selection Pressures ◽  
Genome Wide ◽  
A Genome ◽  
Wide Range

Parallel changes in genotype and phenotype in response to similar selection pressures in different populations provide compelling evidence of adaptation. House mice (Mus musculus domesticus) have recently colonized North America and are found in a wide range of environments. Here we measure phenotypic and genotypic differentiation among house mice from five populations sampled across 21° of latitude in western North America, and we compare our results to a parallel latitudinal cline in eastern North America. First, we show that mice are genetically differentiated between transects, indicating that they have independently colonized similar environments in eastern and western North America. Next, we find genetically-based differences in body weight and nest building behavior between mice from the ends of the western transect which mirror differences seen in the eastern transect, demonstrating parallel phenotypic change. We then conduct genome-wide scans for selection and a genome-wide association study to identify targets of selection and candidate genes for body weight. We find some genomic signatures that are unique to each transect, indicating population-specific responses to selection. However, there is significant overlap between genes under selection in eastern and western house mouse transects, providing evidence of parallel genetic evolution in response to similar selection pressures across North America.

scholarly journals Status of woodland caribou in Alberta

Rangifer ◽  
1998 ◽  
Vol 18 (5) ◽  
pp. 111 ◽  
Author(s):  
J. Edmonds
Keyword(s):  
Rangifer Tarandus ◽  
Oil And Gas ◽  
Timber Harvesting ◽  
Conservation Strategy ◽  
Peat Moss ◽  
Woodland Caribou ◽  
Oil And Gas Development ◽  
The North ◽  
Wide Range ◽  
Multi Stakeholder

A recent review of woodland caribou {Rangifer tarandus caribou) status in Alberta estimated that there are between 3600 and 6700 caribou occupying 113 000 km2 of habitat. There are two ecotypes of caribou in Alberta; the mountain ecotype in the west central region and the boreal ecotype primarily in the north. Mountain caribou populations are stable or declining and boreal populations, where data are available, appear to be stable or declining slowly. A major initiative in caribou management in Alberta has been the development of the Woodland Caribou Conservation Strategy. This document was developed over two and a half years by a committee of multi-stakeholder representatives. The past five years has seen an increase in baseline inventory and applied research jointly funded by government, industry and universities, addressing a wide range of management issues from caribou response to logging to interactions of moose, wolves and caribou in the boreal ecosystem. Land use conflicts on caribou range remain high with timber harvesting, oil and gas development, peat moss extraction, coal mining, agricultural expansion and increasing road access overlapping. Cumulative effects of these disturbances are poorly understood and have received little attention to date.

Estimating the biomass of woodland caribou forage lichens

2011 ◽  
Vol 41 (10) ◽  
pp. 1961-1969 ◽  
Author(s):  
Richard Troy McMullin ◽  
Ian D. Thompson ◽  
Brian W. Lacey ◽  
Steven G. Newmaster
Keyword(s):  
Boreal Forests ◽  
Food Source ◽  
Rangifer Tarandus ◽  
Ecological Studies ◽  
Woodland Caribou ◽  
Wide Range ◽  
Winter Food ◽  
Biomass Assessment ◽  
Biomass Ratio ◽  
Lichen Growth

Lichens are an important winter food source for woodland caribou ( Rangifer tarandus caribou ), but quantifying their abundance is difficult. Here, we present an efficient method for assessing lichen biomass at the stand level in boreal forests. We measured lichens occurring in high enough abundance to serve as a winter food source for woodland caribou in 51 boreal forest stands. Samples of each species or genus were collected from each stand and a mean abundance (cover) to biomass ratio was established. The method does not require samples to be collected or weighed, due to this predetermined relationship, and it also accounts for the variation in biomass among lichen species that are equally abundant. The variation in lichen growth between stands was assessed by means of five lichen abundance classes. The proposed method was tested in 34 stands with a wide range of ages and stem densities. The average time to complete a lichen biomass assessment was approximately 2 h. This method is an efficient and accurate tool that can assist forest managers and researchers with ecological studies on lichens or with monitoring changes in lichen biomass over time and with habitat assessments for organisms for which lichens are important, such as woodland caribou.

SOME TRENDS IN GRASSLAND FARMING IN EUROPE

1977 ◽  
pp. 5-19
Author(s):  
R.W. Brougham
Keyword(s):  
Land Use ◽  
Crude Protein ◽  
Energy Usage ◽  
Hill Country ◽  
Wide Range

IN an assessment such as this, one could cover a wide range of topics fairly shallowly or a lesser number in a bit more depth. I have opted for the latter. The topics discussed will embrace some trends in dairying, beef farming, sheep farming, hill country farming, and land use generally, species and variety usage in grassland farming, use of crude protein produced from pasture, and some implications of energy usage.

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