bluuebunny/crossref_metadata_2025 huggingface dataset:
Vegetation biomass and habitat selection by a newly introduced population of muskoxen in northern Quebec
Authors: Nault René , Mathieu Carole , Crête Michel
Published: February 2013

Ground coverage by woody and herbaceous plant species and standing biomass of vegetation susceptible to being grazed upon were estimated in a 156 km2 area where 190 muskoxen were censused during the preceding autumn. Habitat use was estimated with droppings census. Six terrestrial habitat types were delineated on 1:32 000 aerial photographs and randomly sampled: low shrub on xeric sites (LSX; 64 km2), low shrub on mesic sites (LSM; 45 km2), bare ground (BG; 27 km2), forest-tundra (FT; 12 km2), wet meadow (WM; 2 km2) and riparian willows (RW; 1 km2). Dominant plant species varied greatly between habitat types, and only a few such as Betula glandulosa, Salix arctophila, and Polygonum viviparum were common. Tall shrubs were present only in RW where they covered most of the ground, and in FT. Low shrubs were uniformly distributed and covered 18-32% of the ground, with the exception of RW (5%). Ground cover by herbs had a similar range (i.e. 20-37%), except in RW where the mean exceeded 50%. Mosses and lichens occupied about half of the ground everywhere. Phytomass exhibited great variation within and between habitat types; extreme values averaged 892 kg*ha-1 in LSX, and 1965 kg*ha-1 in LSM. However the difference was not significant due to limited sample size and within habitat variance. Nevertheless the mass of herbaceous dicots was greater in RW than in any other habitat type. Total phytomass was 2-20 times greater in northern Québec than in Greenland. Based on droppings density, muskoxen preferred RW over BG and FT, and LSX over BG. Although the density of muskoxen in the study area was high relative to other muskox ranges, habitat quality and quantity should allow continued population growth.
Twinning in muskox and the cytogenetic investigation of a freemartin
Authors: Reindl N. J. , Buoen L. C. , Zhang T. Q.
Published: February 2013

The occurrence of twinning has been documented for muskox in both wild and captive populations. Of two known captive twin births only one set survived beyond 120 days. In both cases the twins were male-female pairs and both females showed abnormal sexual development. Two sets of stillborn twins have also been recorded. All four stillborn fetuses were female and none showed anomalies of the reproductive tract upon post-mortem examination. Blood cultures from the surviving male and female twins revealed that both were chimeric, indicating the admixture of fetal blood. Fibroblast cultures were normal for the respective sex of each individual. The freemartin heifer had anatomical abnormalities of the clitoris as well as the secondary sex characteristics of a male.
Dynamics of muskox groups in northeastern Alaska
Authors: Reynolds P. E.
Published: February 2013

Group size and stability was studied in a population of re-established muskoxen (Ovibos moschatus) in northeastern Alaska by re-locating radio-collared animals. Mixed-sex groups (cows, calves, sub-adults and often adult bulls) ranged in size from 2-118 with a mean of 19.2. Almost 60 % of all mixed-sex groups contained 5¬19 individuals. Solitary cows were seen infrequently. Adult bulls were observed in mixed-sex groups, in bull groups or alone. Bull groups averaged 3.9 and ranged in size from 2 to 12. Thirty percent of all adult bulls seen outside mixed-sex groups were solitary animals. Mixed-sex groups were significantly smaller in summer/ rut Quly-September) than in midwinter Qanuary-March), spring/calving (April-June) and early winter (October-November). Mean group size was 12.2 in August compared with 23.6 in February. In August, during the rut, numbers of small groups (2-14) increased, while numbers of medium-sized (15-29) and large groups (> 29) decreased. Bull groups were significantly larger in spring/calving than during other seasons. The ratio of single bulls to bull groups was less than 0.30 in winter, increased in June, and reached a maximum during the rut in August when more than 2 single bulls were seen for every bull group. Group size and individuals within a group changed frequently. This fluid social system provides a balance between protection from predators, efficient food acquisition and the formation of harems during the rut.
Causes of variation in growth rate of reindeer calves
Authors: Petersson C. J. , Danell B.
Published: February 2013

Weights of individual reindeer calves were registered on 3 or 4 occasions from the July roundup to the last slaughter roundup in January during each of four consecutive years (1986 to 1989). The observations were made in a tagged herd located in the southern part of the reindeer area in Sweden (63°N, 12°E). A total of 10 400 live-weight measurements were made, and the relationship between pre-slaughter weight and carcass weight was estimated using data from 109 individuals. Variation in weight and weight gain between weighing occasions was related to sex, number of days in the corral, scale and year. Non-linear growth curves were fit to the adjusted weights. For each sex, smoothed average weights and dispersions, both within and between year, as well as the coefficient of variation were calculated from data generated from the estimated functions. Individual calf weights were shown to be influenced by sex, weighing day within occasion, and by year. Reindeer calves gained between 20 and 25 kg in live body weight from two to 6-8 months of age. Male calves were heavier than female calves over the whole period and they gained in live weight on average 10 g/day more than female calves. Between year coefficient of variation was between 1.5 and 7% with the largest variation between years for July and January weights and the lowest variation for September weights. The growth curves showed that the major increase in weight was between July and September. From September to December/January the additional increase was only 5%. Dressing-percentage was influenced by live weight prior to slaughter. A positive relationship between live weight and dressing percentage was shown.
An erosive/ulcerative alimentary disease of undetermined etiology in Swedish moose (AIces alces L.)
Authors: Stéen Margareta , Diaz Regina , Faber William E.
Published: February 2013

During the years 1985 to 1987, 689 moose (Alces alces L.) collected throughout Sweden were necrop-sied at the National Veterinary Institute in Uppsala, Sweden. Sixty-eight of those investigated had catarrhal to hemorrhagic enteritis, atrophied lymphoid organs, and/or numerous erosive, uclerative, necrotizing lesions of the digestive mucosa. Histopathology of the mucous membranes revealed marked inter- and intracellular oedema, erosions, ulcers and intracytoplasmic inclusion bodies. Neither Bovine Virus Diarrhoea/Mucosal Disease (BVD/MD) or Infectious Bovine Rhinotracheitis (IBR) virus could be isolated from the diseased animals. It is suggested that the syndrome resembling BVD/MD complex, may have been caused by an yet unidentified virus.
Preliminary investigations on the parasite burden and distribution of endoparasite species of muskox (Ovibos moschatus) and caribou (Rangifer tarandus groenlandicus) in West Greenland
Authors: Korsholm H. , Olesen C. R.
Published: February 2013

In the autumn 1990 5 muskoxen and 5 caribou from Angujaartorpfiup Nunaa, West Greenland, were parasitologically examined. The findings included gastro-intestinal parasites as Eimeria spp., Ostertagia cir-cumcincta, Ostertagia trifurcata, Teladorsagia davtianiy Marshallagia marshalli, Nematodirella longissimespiculata, Nematodirus helvetianus and Moniezia expansa. No pulmonic or hepatic parasites were detected. A theoretically possible interaction of parasite species between muskox and caribou is most likely in the case of Ostertagia spp. and N. longissimespiculata. Preliminary investigations on the contamination of infective larvae (third stage larvae of gastro-intestinal nematodes) showed great differences on herbage from different types of habitats in the research area. A moist dwarf schrub heat on a north facing slope being the most contaminated (1643 L3/kg of dry herbage).
An examination of the impact of the commercial use of muskox underwool upon Native Alaskan villagers
Authors: Bruce M. , Robertson S.
Published: February 2013

The Musk Ox Producers' Co-operative was begun in 1969 under the «Musk Ox Project», a project aimed at domesticating muskoxen and harvesting their underwool («qiviut»), which would then be handknit into garments by Native Alaskan villagers. The aim of the co-op was to provide the cash income for the villagers without disturbing the villager lifestyle. It was reasoned that by using an Arctic animal to benefit an Arctic people, the villagers could gain income without losing their Native heritage and lifestyle. By examining the past and present status of the Co-operative we can evaluate the impact that it has had on the villagers compared to these original objectives.
The bacteriology of the small intestinal mucosa of free-living reindeer
Authors: Sørmo Wenche , Aagnes Tove H. , Olsen Monica A. , Mathiesen Svein D.
Published: February 2013

Bacteria in close associaton with the intestinal mucosa are thought to protect the mucosa from pathogenic microorganisms. The pH of the small intestinal mucosa and the viable populations of aerobic and anaerobic bacteria associated with the proximal and distal jejunal mucosa, were measured in four free-living reindeer in winter. The anaerobic bacterial populations were characterized. The median pH of the mucosa of the duodenum was 6.6 (n=4) at point 0.2 m from the pyloric sphincter. The mucosal pH increased along the length of the intestine to 8.3 at 14 m and then decreased to 7.9 at 19.8 m from the pyloric sphincter. Examination by transmission electron microscopy and cultivation techniques failed to reveal any bacteria on the mucosa of the proximal jejunum in two of the animals. In two other reindeer the median anaerobic bacterial densities in the proximal jejunum ranged from 25-2500 cells/g mucosa. The median anaerobic bacterial populations in the distal jejunum ranged from 80 to 20000 bacteria/g mucosa (n=4). The anaerobic population of bacteria in the proximal jejunum was dominated by streptococci and unidentified gram positive rods. Bacteroidaceae, streptococci and unidentified gram positive rods were common in the distal jejunum. The low density and the species diversity of bacteria in the small intestine suggests that these microorganisms are inhibited by components in the natural winter diet of reindeer. Bacteria evidently play a minor role in protection of the mucosa of reindeer in winter.
The moose nose bot fly Cephenemyia ulrichii Brauer (Diptera: Oestridae) reported in Norway for the first time
Authors: Nilssen Arne C. , Haugerud Rolf E.
Published: February 2013

Our conclusion is that C. ulrichii has reached the northeastern part of Norway (Pasvik). A further expansion of this parasite may be expected in Norway as well as in southern Sweden. This study shows that moose can be sampled for C. ulrichii with the described technique in the hunting season when the larvae are in their first instar.
Chemical capture of free-ranging red deer (Cervus elaphus) with medetomidine-ketamine
Authors: Arnemo J.M. , Negard T. , Søli N.E.
Published: February 2013

Seventeen free-ranging red deer (Cervus elaphus) (12 calves and 5 yearling hinds) were immobilized with a combination of medetomidine hydrochloride (MED) and ketamine hydrochloride (KET) in winter (January-March). Immobilizations were performed with plastic projectile syringes fired from a dart gun. Mean (SD) doses of 0.147 (0.024) mg MED/kg and 2.5 (0.4) mg KET/kg induced recumbency in 5.0 (2.0) minutes in the calves and all of them were completely immobilized. The initial doses in the yearling hinds were 0.099 (0.016) mg MED/kg and 1.9 (0.2) mg KET/kg but three of them required addirional dosing for induction of reliable restraint. The distance covered by the animals between darting and recumbency ranged from 40-250 m for calves and 100-300 m for yearling hinds. The animals were translocated to deer farms for breeding purposes and were given 12.5-25.0 mg of atipamezole hydrochloride before transportation. All animals recovered completely. Haematological and serum biochemical comparisons between free-ranging calves immobilized with medetomidine-ketamine (n=3) and captive unmedicated calves (n=4) showed that chemical capture induce very little stress in red deer.
Abundance and movements of caribou in the oilfield complex near Prudhoe Bay, Alaska
Authors: Cameron R.D. , Lenart E.A. , Reed D.J. , Whitten K.R. , Smith W.T.
Published: February 2013

We examined the distribution and movements of 141 radiocollared female caribou (Rangifer tarandus granti) of the Central Arctic Herd during summer, 1980-1993. Numbers of caribou locations within each of 5 quadrats along the arctic coast were totalled separately for days during which insects were active and inactive, and numbers of east-west and west-east crossings of each quadrat mid-line were determined from sequential observations. Both abundance and lateral movements of radiocollared females in the quadrat encompassing the intensively-developed Prudhoe Bay oilfield complex were significantly lower than in other quadrats (P < 0.001 and P < 0.00001, respectively). Avoidance of, and fewer movements within, the complex by female caribou are ostensibly in response to the dense network of production and support facilities, roads, above-ground pipelines, and the associated vehicular and human activity. Impaired access to this area constitutes a functional loss of habitat.
Round baled grass silage as food for reindeer in winter
Authors: Aagnes Tove H. , Mathiesen Svein D.
Published: February 2013

Round baled silage of mixed grasses was tested as emergency food for reindeer in winter. The silage was made of leaf rich regrowth of Phleum pratense, Agrostis tenuis and Poa spp. It contained 33-3% dry matter (DM), and 14.8 % crude protein, 24.5% cellulose and 26.7% hemicellulose on a DM basis. Palatability, food intake, digestion, rumen fermentation, body mass (BM), carcass weight and gastrointestinal (GI) anatomy were investigated. A group of adult female reindeer (n = 38), were taken from natural winter pasture and fed grass silage ad libitum. The majority (78%) of the animals were eating silage after two days and 95% of the animals ate silage after five days. Five reindeer calves were taken from natural winter pasture and fed lichens ad libitum for 14 days after which they were starved for two days before being offered silage adlibitum. The median daily DM food intake was 370 g (range 250-610 g) on the first day increasing to 810 g (range 530-1100 g) at days 16 to 20. Median apparent digestibility coefficient (DC) of DM was 64.3% (range 62.4-66.2%). The median in vitro DM digestibility (IVDMD) of the silage after 72 h of microbial digestion was 68.3 % (range 66.6-71.3 %) (Ws=30, n,=5, n2=4, P<0.01). Median ruminal VFA concentration and pH were 48.2 mM (range 38.4-52.5 mM) and 7.0 (range 6.95-7.17), respectively, in the reindeer calves (n=5). BM initially increased when the reindeer calves were fed silage, but stabilised after 11 days. The increased BM may have been due to an increased recticulo-rumen digesta load, which amounted to 19.6-23.7 % of BM (n=3). The carcass weight of the reindeer calves was 42.6-44.2% of the BM (n=3) after 47 days of silage feeding. The results indicate that although the round bale silage of mixed grasses of medium quality was highly palatable to reindeer it was apparantly of only limited value as an emergency food for the reindeer calves, as indicated by low DC of DM and low ruminal VFA concentration.
Comparison between grass-silages of different dry matter content fed to reindeer during winter
Authors: Nilsson Anna , Olsson Ingemar , Lingvall Per
Published: February 2013

A study was made of whether the dry matter content of silage influenced performance when 17-month-old male reindeer were fed solely silage outdoor during winter. Two kinds of round-baled silages with different wilting times were offered to the animals; low dry matter (LDM silage) with a mean of 39% DM, or high dry matter (HDM silage) with a mean of 53% DM. The 115 reindeer were allotted to slaughter at the start of the experiment in October or to be fed until slaughter in January or March. During the first three weeks of the experiment small amounts of lichens were mixed with the silages and the reindeer adapted to the feeding without problems. The daily intake of DM did not differ significantly between reindeer fed the LDM or the HDM silage despite a highly significant difference in daily silage intake. This resulted in small but significantly higher gains in live weight for animals fed the LDM silage, caused by increased weight of the rumen content. All groups of reindeer either retained or lost carcass weight during the experiment, and no improvements or differences were obtained between the kinds of silages in carcass assessment or gains in fat in the abdominal cavity. Animals slaughtered in January had a lower carcass weight and dressing percentage than reindeer slaughtered in October and March. Environmental conditions during the experiment were good but nonetheless mobbing and illness still occurred. The present results concur with those of earlier studies suggesting that it seems to be the bulk of the ration rather than the dry matter content of the silage that limits the intake.
Gross anatomy of the gastrointestinal tract in reindeer, free-living and fed baled timothy silage in summer and winter
Authors: Aagnes Tove H. , Mathiesen Svein D.
Published: February 2013

The gross anatomy of the gastrointestinal (GI) tract was investigated in reindeer calves (Rangtfer tarandus tarandus), free-living and fed two different qualities of timothy silage in September 1992 (summer) and April 1993 (winter) and related to the body condition. At both seasons nine male reindeer calves were taken from a natural pasture. Three animals were slaughtered directly (NP reindeer), three offered first cut (FC) silage and three regrowth (RG) silage ad lib., for 46 days. The FC silage contained 27% leaves and 57.8% dry matter (DM) cell wall content (CWC) and the RG silage 89 % leaves, and 38.7% DM CWC. The reticulo-rumen (RR) digesta wet weight in the NP reindeer in summer was 6.7-7.7% of body mass (BM), compared to 25.1-32.8% and 9.6-12.9% of BM, respectively, in the animals fed FC and RG silage. In winter the RR digesta wet weight relative to BM in the NP reindeer and in the animals fed FC and RG silages were 9-5-11.5%, 25.4-33.3% and 10.4-18.3%, respectively. The distal fermentation chamber (DFC) digesta wet weight in the NP animals in summer was 0.48-0.80% of BM, compared to 0.77-1.26% and 0.57¬0.65% of BM, respectively, in the animals fed FC and RG silage. In winter the DFC digesta wet weight relative to BM in the animals fed FC and RG silage did not differ significantly from the summer values (P>0.05), while in the NP reindeer it was 1.0-1.2% of BM which is significantly greater than in summer (P<0.05). The differences in relative weight of the fermentation chambers between the animals fed FC and RG silage both summer and winter were not reflected in total BM, which was similar in all groups fed silage. This is explained by a significantly lower carcass weight in the animals fed FC silage compared to the animals fed RG silage. Thus, the GI-tract gross anatomy in the silage fed animals seem to be highly affected by the plant structure and composition, and not by the season.
Requirements for maintenance and live weight gain of moose and wapiti calves during winter
Authors: Cool Normand , Hudson Robert J.
Published: February 2013

Energy requirements of moose (Alces alces) and wapiti (Cervus elaphus) calves were compared from December to February to determine whether metabolic requirements were lower in a boreal-adapted than in a parkland-adapted wild cervid. Eight calves of each species were divided equally into groups given high or low quality diets. Regression of metabolizable energy intake on liveweight gain provided estimates for maintenance and gain, Metabolizable energy requirements for liveweight maintenance were 560 kj/kg0.75.d and for gain were 27 kj/g. Neither value was significantly different between moose and wapiti nor between genders within species. This similariry in winter metabolism and consistency with the interspecies mean suggests that winter metabolic dormancy is not necessarily an important part of a seasonal energetic strategy. The main difference was that moose calves maintained appetite and continued to grow throughout the winter.
Proceedings Issue No. 1 - 2nd Arctic Ungulate Conference
Authors: Haugerud (ed.) Rolf Egil
Published: February 2013

The 2nd International Arctic Ungulate Conference was held 13-17 August 1995 on the University of Alaska Fairbanks campus. The Institute of Arctic Biology and the Alaska Cooperative Fish and Wildlife Research Unit were responsible for organizing the conference with assistance from biologists with state and federal agencies and commercial organizations. David R. Klein was chair of the conference organizing committee. Over 200 people attended the conference, coming from 10 different countries. The United States, Canada, and Norway had the largest representation. The conference included invited lectures; panel discussions, and about 125 contributed papers.
Arctic ungulates at the northern edge of terrestrial life
Authors: Klein David R.
Published: February 2013

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.
Canadian Muskoxen in Central Europe - A Zoo Veterinary Review
Authors: Seidel K.B. , Rowell J.E.
Published: February 2013

This paper summarizes 29 years of veterinary experience maintaining a herd of muskoxen at the Tierpark Berlin-Friedrichsfelde, Berlin, Germany. The transplanted muskoxen acclimated to the zoo enviroment without fatalities. However, a few striking changes were seen. They exhibit a high sensitivity to sudden changes in weather conditions (especially falling atmospheric pressure); there is a tendency for their qiviut to become sparser with time; rutting and subsequent calving occur later than in their native habitat. Details of medical conditions in both calves and adults ate given along with information on hematology and immobilization.
Influence of diet on the morphology of the ruminal papillae in reindeer calves (Rangifer tarandus tarandus L.)
Authors: Josefsen Terje D. , Aagnes Tove H. , Mathiesen Svein D.
Published: February 2013

The influence of diet on the morphology of reindeer ruminal papillae was investigated in 4 groups of 3 free-ranging reindeer calves at different seasons, and in 11 groups of 3 reindeer calves fed experimental diets. Length, cross-sectional perimeter and density (number/cm2) of the ruminal papillae were measured in 4 sample sites in the rumen wall, and the ruminal surface enlargement factor (SEF) was calculated at each sample site. The range of group means were 2.3 to 3.4 mm for overall papillary length (mean of the four sample sites), 2.2 to 3.5 mm for overall cross-sectional perimeter, 85 to 189 papillae/cm2 for overall papillar density and 5.8 to 18.6 for overall SEF. Differences between sample sites wete observed, atrium ruminis having the highest and caudodorsal blind sac the lowest SEF (25% over and 24% below overall value, respectively). The differences between sample sites were considered to be small, indicating a homogenous ruminal content. The SEF of free-ranging animals showed a seasonal pattern, with high overall SEF (18.6) in September (late summer) and lower overall SEF {9.1) in April (late winter). Groups fed timothy silage with low content of cellulose (18.7% of dry matter) showed highest overall SEFs of the fed animals (17.8 and 13.9), while groups fed timothy silage with high content of cellulose (30.4%' of dry matter) showed lowest overall SEFs (5.8 and 7.0), indicating low ability to ferment silage with high content of cellulose. The SEF in animals fed experimental diets seemed partly to be influenced by SEF at the beginning of the feeding period.
Evaluation of silage diets offered to reindeer calves intended for slaughter. I. Feeding of silage and barley from September to March
Authors: Nilsson Anna , Olsson Ingemar , Lingvall Per
Published: February 2013

An experiment involving 75 male reindeer calves (mean initial live weight 39.6 kg, SD=3.7) intended for slaughter was undertaken to study the effect of proporrion of barley to silage in the diets on animal performance. The calves were alloted to five groups including one group slaughtered at the start of the experiment in September. The remaining groups were offered diets containing either, 30% (LB), or 60% (HB) rolled barley, based on the dry matter (DM) content, until slaughter in November (LB and HB) or in March (HB). The silage (43% DM) was made from the primary growth of a predominantly grass sward preserved as plastic-wrapped big bales. Small amounts of lichens were mixed with the rations during rhe first two weeks of the experiment and the calves adapted well to the experimental diets. However, health problems and deaths occurred on borh rarions after five weeks of feeding. Since the animals fed the LB diet lost live weight and condition the experimental feeding of these calves were interrupted at the slaughter in November. Calves fed the LB diet had significantly lower daily DM intake (P<0.01). They also had lower live weighr gain (not significant), greater losses of carcass weight and fat in the abdominal cavity relative to those offered the HB diet. During the second period of the study the remaining animals offered the HB diet showed no signs of ill-health and increased live weight, carcass weighr, and fat in the abdominal cavity. The results of the presenr experiment indicate that when silage of the investigated quality is fed to reindeer calves rhe proportion of silage should not exceed 40% of the DM.
Population Ecology of Caribou Populations without Predators: Southampton and Coats Island Herds
Authors: Quellet Jean-Pierre , Heard Douglas C. , Mulders Robert
Published: February 2013

This paper is a review of the ecology of two caribou populations inhabiting predator-free northern islands, Coats and Southampton Island. Findings are analyzed in light of the hypothesis that in absence of prédation or high human harvest, food competition results in delayed puberty, reduced calf production, increased winter starvation of caribou and regulates populations at high densities (>2 km-2). Caribou were hunted to extinction on Southampton Island (Northwest Territories, Canada) by mid-century. In 1967, 48 caribou were captured on neighbouring Coats Island and released on Southampton Island. Southampton Island is characterized by a high per capita winter food availability in summer and in winter. The population on Southampton Island has been increasing at a rapid rate of growth since re-introduction (Lamba=1.27). Fast population growth was possible because females invested early in reproduction and over winter survival rate was high. The population on Coats Island is also characterized by high per capita food availability in summer but low food availability in winter. The population size has undergone some marked fluctuations, abrupt declines followed by relatively rapid recovery and, contrary to predictions, densities were always less than 1 km-2. Low population densities on Coats Island result primarily from low food availability. This review suggests that in the absence of prédation or high human harvest competition for food regulates caribou population abundance. However, caribou numbers can fluctuate markedly among years because inter-annual variation of weather conditions affects forage accessibility in winter. This review also emphasizes the importance of distinguishing between factors that determine absolute population density and variation in density among years (in our case probably plant production and winter weather conditions which influence forage accessibility) from the regulatory factors, processes that stop population increase (competition for winter food leading primarily to density dependent changes in mortality from starvation) when examining population dynamics.
The relationship between food intake and predation risk in migratory caribou and implications to caribou and wolf population dynamics
Authors: Heard Douglas C. , Williams T. Mark , Melton Derek A.
Published: February 2013

We examined the hypothesis that spring migration in barren-ground caribou (Rangifer tarandus) enhances access to high quality food, reduces predation risks or both. We related our findings to the hypothesis that one of the consequences of migration is that prey populations cannot be regulated by predation because predators are unable to respond numerically to changes in abundance of migratory prey. In the Northwest Territories, migration to calving grounds by pregnant cows reduced the risk of predation on neonates. Wolf (Canis lupus) densities on calving grounds averaged only 22% of winter range densities because most wolves denned near tree line. The quality and quantity of food that was available to cows that migrated to calving grounds was lower than for bulls and other caribou that lagged far behind the pregnant cows during spring migration. Fecal nitrogen levels were higher in bulls than in cows in late May and early June but there were no differences in mid or late June. Areas occupied by bulls in late May had a greater biomass of live sedges than on the calving ground in early June. It appears that although food in July is abundant and nutritious, insect harassment prevents efficient feeding. Body fat reserves in both sexes declined to almost zero by mid-July, the lowest level of the year. Insect numbers declined in August and body fat levels increased to the highest level of the year by early September. Because the timing of caribou's return to the hunting ranges of tree line denning wolves was related to caribou density, our data were inconsistent with the suggested consequence of migration. Tree line denning by wolves and density-dependent changes in caribou migration suggests a mechanism for population regulation in caribou and wolves. We suggest that the process is as follows; when caribou numbers increase, some density-dependent factor causes range expansion in August (e.g., competition for food) causing caribou to return earlier to the hunting ranges of tree line denning wolves, more denning wolves have access to caribou, wolf pup survival increases and wolf numbers increase. The effect on caribou population growth will depend on the timing and magnitude of the wolf numerical response.
Ecology of the Porcupine caribou herd
Authors: Whitten Kenneth R.
Published: February 2013

Researchers have described general patterns of population regulation that fit most caribou (Rangifer tarandus) herds. Nevertheless, specific factors operating on particular populations vary greatly, and efforts to categorize herds according to the general patterns often lead to confusion. It is difficult for biologists to attempt to describe population dynamics in terms of density relationships for wide-ranging arctic caribou such as the Porcupine Herd. In these herds density varies as a function of dispersal and erratic movement patterns and is not simply the number of caribou divided by a fixed range area. Density is also a poor surrogate for resource availability per individual caribou because climatic factors affect forage and/or access to forage independendy of caribou numbers. Thus classic signs of nutritional stress such as delayed puberty, reduced productivity, and winter starvation can occur when a population is small as well as large and do not necessarily denote food competition brought on by high density, per se. Nutritional stress and exacerbated predation due to adverse weather conditions occasionally cause the Porcupine Herd to decline, and limiting factors such as poor nutrition, predation, harvest, accidents, and disease act in combination to keep herd growth rates low during periods of good weather. Adverse weather setbacks occur frequently, and the herd remains within a fairly restricted range of densities over long time periods. There is no true density dependent regulation and no equilibrium in this system.
Evolving perspectives on caribou population dynamics, have we got it right yet?
Authors: Bergerud A.T.
Published: February 2013

The roles of food, weather and predation are compared between sedentary and migratory caribou herds. Sedentary herds disperse (space out) at calving time while the cows of migratory herds move in masse (space away) to calving grounds to reduce predation risk. The sedentary ecotype calves on ranges near open water if tree cover is present or in rugged topography in the absence of tree cover. The migratory ecotype aggregates on calving grounds located on alpine mountain plateaus or on the tundra north of the Arctic tree line. The two herds with the greatest densities in North America, the sedentary Slate Islands Herd and the migratory George River Herd both had changes in abundance that followed summer food problems. The hypothesis that winter lichen supplies determine abundance and set the carrying capacity is rejected. Lichens are not a necessary food for caribou. A review of the mortality of young calves documented in the past 30 years provides no support for the hypothesis that hypothermia is a common mortality problem. Young calves documented can be born inviable at birth if their dams are severely malnourished. The migratory caribou in North America reached peak numbers in the 1980s after wolf populations were heavily harvested in the 1970s. The sedentary ecotype is frequently regulated by wolf predation that affects both recruitment (R) and the mortality of adults (M). The balance between R/M schedules commonly occurs when R (calves) represents, about 15% of the herd and when numbers (prorated to the area of the dispersed annual range) approximate 0.06 caribou/km2. Population limitation of migratory herds by predation has occurred in the NWT and in several herds in Alaska but only when wolf densities were > 6.5/1000 km2. Wolf predation halted the growth of the George River Herd in 1980 but then wolves contracted rabies and the herd again increased and degraded spring/summer ranges. The reduced summer phytomass resulted in lower birth rates and increased the vulnerability of calves and possibly adults to wolf predation. Stabilizing mechanisms for migratory herds include movements between herds above tree line and range contractions/expansions with resultant changes in demography. It is hypothesized that the most important ecological variable in all seasonal distributions of caribou is predation risk rather than to maximize forage supplies.
Using Alternative Silvicultural Systems to Integrate Mountain Caribou and Timber Management in British Columbia
Authors: Armleder Harold M. , Stevenson Susan K.
Published: February 2013

Even-aged forest management using the clearcutting silvicultural system as it is currently applied threatens mountain caribou habitat in British Columbia. Since neither complete preservation nor maximum development of timber resources are socially acceptable alternatives, forest managers are anxious to find integrated management options. We describe alternative silvicultural systems currently being tested, including single-tree and group selection. All the treatments have the goal of periodically extracting viable timber volumes while perpetually retaining stand characteristics necessary for caribou. The effects of these logging prescriptions on lichen biomass and growth rates are being tested. Alternative silvicultural systems may become part of a larger strategy to maintain caribou habitat in managed forests.
Integrated Management of Mountain Caribou and Forestry in Southern British Columbia
Authors: Simpson Keith , Kelsall John P. , Leung Maria
Published: February 2013

Integrated Management of Mountain Caribou and Forestry in Southern British Columbia
A Cooperative Industry - Government Woodland Caribou Research Program in Northeastern Alberta
Authors: Rippin Blair , Edey Colin , Hebert Daryl , Kneteman Jeff
Published: February 2013

Rapid development of large scale logging and increasingly intensive petroleum exploration and development in northeastern Alberta prompted the establishment of a cooperative research program to investigate various aspects of woodland caribou (Rangifer tarandus caribou) biology. The ultimate goal of the program is to develop an effective plan that will ensure the long term survival of caribou while allowing for renewable and non-renewable resource development. There are three parts to the program. Part I began early in 1991 and makes use of conventional radio telemetry as a means of recording various parameters of general caribou biology. The study area encompasses approximately 4000 km2 of low relief, boreal mixedwood forest. Preliminary results from 2500 radio locations (involving 50 individuals) indicate that woodland caribou inhabiting the study area are non-migratory and are strongly associated with some of the more scarce peatland forest types present in the area. Investigations to document the basic biology and ecology will continue for another two years. Part II began in early 1993 as a part of a two-year investigation into the disturbance effects of petroleum exploration and development on caribou movements and behaviour. One objective of this study is to develop a predictive model useful in determining the cumulative effects of varying intensities of disturbance on caribou. Part III began in early 1994 with a proposed three-year investigation to determine the mechanism of spatial and temporal separation of caribou and moose in the study area. These relationships may indicate the means by which caribou minimize the impact of wolf predation on their populations in northeastern Alberta. Results will be applied to industrial land use and specifically to large scale forest harvesting planned for the area. The research program is supported through cooperative funding contributed by 24 petroleum companies, 1 forest company, 2 peat companies and the Alberta Departments of Environmental Protection and Energy. The research aspect of the program has been developed and implemented by staff of the University of Alberta, Alberta-Pacific Forest Industries, the Alberta Fish and Wildlife and Forest Services and the Alberta Environmental Centre. The program also incorporates a public information and liaison function. Newsletters, information videos, brochures and public consultation are the means used to accomplish this task.
Successful and unsuccessful attempts to resolve caribou management and timber harvesting issues in west central Alberta
Authors: Hervieux David , Edmonds Janet , Bonar Richard , McCammon Jim
Published: February 2013

Research studies of woodland caribou in west central Alberta began in 1979 in response to proposed timber harvesting on their winter ranges. Using results from initial studies, timber harvest guidelines were developed. A recent review of these guidelines, and the assumptions on which they were based, has resulted in a renegotiation by government and industry of timber harvesting on caribou range in west central Alberta. Caribou range in west central Alberta overlaps many jurisdictional boundaries: federal and provincial lands, four Forest Management Agreement Areas, three Alberta Land and Forest Service Regions and two Alberta Fish and Wildlife Service Regions. This jurisdictional complexity in combination with other factors such as total allocation of the timber resources, high levels of petroleum, natural gas and coal extraction activities, a high level of concern by public groups for caribou conservation and recent understanding of woodland caribou needs for abundant space has made resolution of caribou/timber harvest conflicts exceedingly slow and often relatively unproductive. This paper reviews 10 years of trying to resolve conflicts between timber harvesting and caribou conservation through meetings, committees, integrated resource planning, policy papers and public consultation. We describe what might be learned by other jurisdictions that are trying to resolve similar caribou/timber harvesting issues. We conclude with an overview of recent timber harvest planning initiatives on caribou range in west central Alberta.
Winter foraging dynamics of woodland caribou in an artificial landscape
Authors: Rominger Eric M. , Robbins Charles T.
Published: February 2013

The data suggest that arboreal lichen biomass and/or bite size are primary factors influencing intake rate. Caribou did not increase bite rate to compensate for smaller bite sizes or decreased biomass. Forest management should enhance lichen production to maximize intake rates for woodland caribou.
Canopy, snow, and lichens on woodland caribou range in southeastern Manitoba
Authors: Schaefer James A.
Published: February 2013

I examined the relationships among snow cover (api), lichen abundance, and canopy composition on the range of the Aikens Lake population of woodland caribou (Rangifer tarandus caribou) in southeastern Manitoba. Percent cover of forage lichens (Cladina spp.) was positively correlated with maximum total thickness and with maximum vertical hardness of api. Mixed communities of trembling aspen (Populus tremuloides), spruce (Picea spp.), and balsam fir (Abies balsamea) showed the most favourable nival conditions for caribou but had low lichen abundance; those dominated by jack pine (Pinus banksiana) were the converse. The results suggest an energetic compromise for woodland caribou when foraging for terrestrial lichens. During winter, caribou exhibited significant selection for jack pine communities whereas mixed communities were avoided.
Structures for caribou management and their status in the circumpolar north
Authors: Klein D.R.
Published: February 2013

Large herds of caribou (Rangifer tarandus) in Canada, Alaska, and Russia that winter in northern coniferous forests and summer in tundra of the Arctic have provided a sustainable source of meat and other products for indigenous peoples for thousands of years. Several different administrative structures for management of large caribou herds have emerged throughout the circumpolar North. In Russia under the previous Soviet government, the herd of the Taimyr Region, numbering around 500 000 caribou, was managed under a harvest quota system for both subsistence use by indigenous people and commercial sale of meat and skins. In North America, as indigenous peoples have gained increasing political empowerment, systems for caribou management have been undergoing change. Establishment of the Beverly and Qamanirjuaq Caribou Management Board in Canada, with majority representation from users of the resource, provides a model and a test of the effectiveness of a comanagement system. The Western Arctic Herd in northwestern Alaska, numbering close to 500 000 caribou, has been managed under the traditional American system of game management, with user advisory groups, but with management decisions resting with a statewide Board of Game, whose major representation is from sport-hunting interests. The Porcupine Caribou Herd, which is shared by the United States and Canada, is the focus of an international agreement, in principle designed to assure its continued productivity and well-being. The diversity of systems for caribou management in the circumpolar North provides an opportunity for comparing their effectiveness.
Peary caribou, muskoxen and Banks Island forage: Assessing seasonal diet similarities
Authors: Larter Nicholas C. , Nagy John A.
Published: February 2013

Peary caribou (Rangifer tarandus pearyi) and muskoxen {Ovibos moschatus) on Banks Island had considerable similarity in their annual diets, with monthly similarities ranging from 17.8-73.3%. Diet similarity was more pronounced in areas of high muskox density {ca. 1.65/km2) than in areas of low muskox density {ca. 0.4/km2). Willow (Salix arctica) and sedge (Carex aquatilis and Eriophorum spp.) represented >80% of the monthly diet of muskoxen. The caribou diet was more diverse, and was dominated by sedge, willow, Dryas integrifolia, and Oxytropis maydelliana, Lichen use was rare, likely as a consequence of low availability on Banks Island. Lichen standing crop was estimated at 2.96 g/m2. The differences in muskox diet between high and low density areas could not be explained by differences in forage distribution or standing crop. We discuss diet similarities of caribou and muskoxen and potential consequences for the current Peary caribou population in relation to winter weather conditions and increasing muskox density.
Proceedings of the 2nd International Arctic Ungulate Conference, Fairbanks, Alaska, 13-17 Aug 1995: Issue No. 2
Authors: Haugerud (editor) Rolf Egil
Published: February 2013

This issue of the proceedings of AUC 1995 is the 2nd of four issues. Issues 1, 3 and 4 are found respectively in Rangifer 1996, 16 (2): 49-92; 1997, 17 (3): 10-138 ; 1998, 18 (3-4): 99-154. A list of contents of the four proceedings issues is found in the latter proceedings issue.
In defence of "anecdotal data". A case study from a caribou area in West Greenland
Authors: Blehr Otto
Published: February 2013

The author pleads for a modification of ethological science that allows for the presentation of even tentative hypotheses, based on what is at present disparagingly referred to as "anecdotal data". It is argued that such data are crucial for the neglected study of the habituation of free-ranging large mammals. In such studies of learning, relevant behavioural observations lie outside the ethologist's control, and can only be replicated by further chance encounters. Observations in their anecdotal form should therefore be made available to other ethologists despite their lack of quantifiable data. This would allow for the creation of a pool of more or less unique observations helping to better understand behaviour.
Energy-expending behaviour in frightened caribou when dispersed singly or in small bands
Authors: Blehr Otto
Published: February 2013

The behaviour of single, and small bands of caribou (Rangifer tarandus groenlandicus) when confronted by humans was compared with the energy—saving behaviour zoologists have ascribed to caribou in encounters with non-hunting wolves (Canis lupus). When confronted by me, or upon getting my scent, caribou ran away on all occasions. Their flight was occasionally interrupted by short stops to look back in my direction, but would continue on all occasions until they were out of sight. This behaviour is inconsistent with the one ascribed to caribou by zoologists when the intruder is a wolf instead of a human. In their view, the caribou stop their flight soon after the wolf gives up the chase, and accordingly save energy owing to their ability to distinguish between hunting and non-hunting wolves. However, small bands of caribou, as well as single animals, have never been observed to behave in this manner. On the contrary, the behaviour of caribou in such encounters is known to follow the same pattern as in their encounters with humans. Energy—saving behaviour is, however, sometimes observed when caribou become inquisitive about something in their surroundings. They will then readily approach as well as try to get down-wind of the object. When the object does not induce fear, it may simply be ignored, or charged before the caribou calm down. The effect of this "confirming behaviour" is that energy which would otherwise have been spent in needless flights from non-predators is saved.