Groups Of Reindeer Research Articles

Study of the genetic structure of domestic and wild reindeer in the Republic of Sakha (Yakutia) using STR analysis

Aim: evaluation of the current state of the genetic and allelic diversity of domestic and wild reindeer populations inhabiting the territory of the Republic of Sakha (Yakutia), using STR markers.Materials and methods. The sample of the domestic reindeer included animals from Even (EVN, n=33), Evenk (EVK, n=31), and Chukchi (Khargin) breeds (KH, n=33). The sample of wild reindeer comprised representatives of the tundra (WLD_TUN, n=119) and taiga (WLD_TGA, n=14) populations.Polymorphism analysis of 14 STR loci including NVHRT21, NVHRT24, NVHRT76, RT1, RT6, RT7, RT9, RT27, RT30, RT25, RT13, NV03, RT5, and NV73 was performed using proprietary methods on ABI3130xl genetic analyzer (Applied Biosystems, USA).Allelic and genetic diversity parameters were calculated using GenAlEx software (ver. 6.5.1) and R package “diveRsity”.To address the genetic structure, Principal Component Analysis (PCA) was performed using the R package adegenet and visualized in the R package gglot2.The genetic differentiation of reindeer populations was performed based on a matrix of pairwise FST values and visualized as a phylogenetic tree using the Neighbor-Net algorithm in the SplitsTree 4.14.5 program.Results. Analysis of genetic diversity parameters showed that the observed heterozygosity was the lowest in WLD_TGA (HO = 0.520) among all studied groups and varied from 0.615 in KH to 0.691 in EVK. All reindeer groups were characterized by a heterozygote deficit, as evidenced by the positive values of the inbreeding coefficient: from UFIS = 0.101 in EVK to UFIS = 0.372 in WLD_TGA. The mean number of alleles per locus varied from 7.1 in EVN to 12.4 in WLD_TUN. Wild reindeer had higher allelic richness (AR = 7.8–8.6 and AR = 6.2–6.8, respectively) and number of effective alleles per locus (NE = 5.3–6, 9 and NE = 4.1 – 4.5, respectively) in comparison with their domestic relatives. Principal Component Analysis showed that the first Principal Component separated wild reindeer from the domestic reindeer. Analyzing pairwise FST values, we found that the KH was the most genetically distant from domestic reindeer breeds (FST = 0.072 between KH and EVN, and FST = 0.065 between KH and EVK) and from wild reindeer populations (FST = 0.076 between KH and WLD_TGA, and FST = 0.06 between KH and WLD_TUN). Pairs EVN and EVK (FST = 0.047), as well as WLD_TUN and WLD_TGA (FST = 0.008) were characterized by insignificant genetic differentiation. Neighbor Net graph showed the formation of two clusters including wild and domestic reindeer populationsConclusion. The results may be useful for development of breeding programs for breeds of domestic reindeer and conservation programs for wild reindeer.

Genome-Wide SNP Analysis Reveals the Genetic Diversity and Population Structure of the Domestic Reindeer Population (Rangifer tarandus) Inhabiting the Indigenous Tofalar Lands of Southern Siberia

Operating under the assumption that decline in population size increases the threat of loss of genetic diversity, herein, our first aim was to monitor and document the genetic diversity and population structure of the endemic Tuva–Tofalar reindeer, the number of which has seen a dramatic decrease. Second, we were interested in understanding of Tuva reindeer genetic relationship with four officially recognized reindeer breeds, whose wild populations inhabit the Far North of Russia, as well as with the domestic reindeer making up the Mongolian population. Our results, based on the genome-wide SNP genotypes generated by the BovineHD BeadChip, revealed a low level of genetic variability of Tuva population in terms of the values of both allelic and genetic diversity. The ADMIXTURE analysis, the PCA plot, and the Neighbor Net network results, showed that Tuva population shared genetic background with reindeer inhabiting Mongolia, an implication of their common origin. Moreover, all statistic approaches used in our study showed a distinctive shared genetic structure revealed in independent clusters found in the composition of: an admixed cluster of Tuvan and Mongolian populations, a cluster of domestic reindeer breeds, and a cluster of the wild populations—all of which indirectly points to the possibility of the independent origins (with regard to the domestication) of the reindeer groups studied herein. We believe that our findings will contribute to the formation of a rational basis for solving problems related to the conservation of domestic Tuva-Tofalar reindeer in order to increase the number of this substantial reindeer population which will contribute to the sustainable functioning of ecosystems and the lives and culture of indigenous peoples inhabiting the southern sections of Eastern Siberia.

Phenogenetic features of the Nenets breed Ural ecotype of the reindeer

For the first time, comprehensive studies of the phenogenetic features of the Ural ecotype of domestic reindeer of the Nenets breed were performed. It was found out that the Ural reindeer relative to other ecotypes of the Nenets breed have smaller linear dimensions and live body weight. The studied group of reindeer was characterized by the minimum values of the majority of population genetic indicators, including the effective number of alleles (Ne = 4.422 ± 0.614), the Shannon information index (I = 1.663 ± 0.102), and the level of both the observed and expected heterozygosity (Ho = 0.561 ± 0.064 and He = 0.740 ± 0.035, respectively). It exceeded two other samples from neighboring breeding regions (Nenets Autonomous district and the Komi Republic) in the average number of alleles per locus: (Na = 9.667 ± 0.577 versus Na = 9.555 ± 0.669 and Na = 9.557 ± 0.709, respectively). Animals of the Ural population (YAM) have a closer genetic structure with reindeer individuals of the neighboring Nenets Autonomous district (NAO). The studied sample of the Nenets breed was characterized by a shift in genetic diversity towards a lack of heterozygotes, as evidenced by the positive Fis values. The introduction of genetic methods in the reindeer herding will allow improving the breeding work in the industry, revealing intraspecific genetic variation in inbreeding herds and identifying intrabreed groups of animals.

Measuring Faecal Glucocorticoid Metabolites to Assess Adrenocortical Activity in Reindeer.

Simple SummaryWe validated an 11-oxoaetiocholanolone enzyme immunoassay for measuring faecal cortisol metabolites (FCMs) in reindeer. Samples were collected from eight male reindeer following adrenocorticotrophic hormone (ACTH) stimulation and from another group of reindeer during handling and calf marking. The overall FCM levels peaked after seven to eight hours in both locations, proving that the assay is suited to evaluate the adrenocortical activity in reindeer.Several non-invasive methods for assessing stress responses have been developed and validated for many animal species. Due to species-specific differences in metabolism and excretion of stress hormones, methods should be validated for each species. The aim of this study was to conduct a physiological validation of an 11-oxoaetiocholanolone enzyme immunoassay (EIA) for measuring faecal cortisol metabolites (FCMs) in male reindeer by administration of adrenocorticotrophic hormone (ACTH; intramuscular, 0.25 mg per animal). A total of 317 samples were collected from eight male reindeer over a 44 h period at Tverrvatnet in Norway in mid-winter. In addition, 114 samples were collected from a group of reindeer during normal handling and calf marking at Stjernevatn in Norway. Following ACTH injection, FCM levels (median and range) were 568 (268–2415) ng/g after two hours, 2718 (414–8550) ng/g after seven hours and 918 (500–6931) ng/g after 24 h. Levels were significantly higher from seven hours onwards compared to earlier hours (p < 0.001). The FCM levels at Stjernevatn were significantly (p < 0.001) different before (samples collected zero to two hours; median: 479 ng/g) and after calf marking (eight to ten hours; median: 1469 ng/g). Identification of the faecal samples belonging to individual animals was conducted using DNA analysis across time. This study reports a successful validation of a non-invasive technique for measuring stress in reindeer, which can be applied in future studies in the fields of biology, ethology, ecology, animal conservation and welfare.

A Genetic Predisposition to Chronic Wasting Disease in the Reindeer Rangifer tarandus in the Northern European Part of Russia

Nucleotide sequences of the prion protein gene PRNP have been obtained in order to assess potential genetic predisposition to the deadly prion chronic wasting disease (CWD) in three regional groups of wild reindeer and two regional groups of domesticated reindeer Rangifer tarandus in the northern European part of Russia. We report identification of seven single nucleotide polymorphisms corresponding to the substitutions in six codons of the prion protein PrP, namely 2(V/M), 129(G/S), 138(S/N), 169(V/M), 176(N/D), and 225(S/Y). Six alleles of the PrP protein have been described. The genotypes with asparagine (N) in codon 138 (138NN and 138SN), which are associated with higher resistance to CWD, were detected in 8.7, 14.3, and 18.2% of animals in the wild reindeer groups from Novaya Zemlya, Kola Peninsula, and the forest regions of Arkhangelsk oblast and the Komi Republic. It has been found that the frequency of these genotypes in domesticated reindeers from the Komi Republic and Kolguev Island was higher, 37.5 and 42.1%, respectively. It has been noted that due to the predominance of PrP genotypes with serine in codon 138 (138SS), which are associated with increased susceptibility to CWD, and the detection of this disease in reindeer, moose, and red deer in Scandinavia, there exists a real danger that CWD will spread among the reindeer inhabiting the European part of Russia.

A century of conservation: The ongoing recovery of Svalbard reindeer

ABSTRACTSeveral caribou and reindeer (Rangifer tarandus) populations have experienced recent population declines, often attributed to anthropogenic stressors such as harvesting, landscape fragmentation, and climate change. Svalbard reindeer (R. t. platyrhynchus), the wild reindeer subspecies endemic to the high‐Arctic Svalbard archipelago, was protected in 1925, after most subpopulations had been eradicated by harvest. Although direct pressure from harvest has ceased, indirect anthropogenic stressors from environmental changes have increased in this climate change hot spot. An assessment of the current distribution and abundance is therefore urgently needed. We combined distance sampling (300 km transects, n = 489 reindeer groups) and total counts (1,350 km2, n = 1,349 groups) to estimate the Svalbard reindeer distribution and abundance across its entire range, which we compared with historical data from the literature and radiocarbon‐dated bones. Reindeer have now recolonized nearly all non‐glaciated land (i.e., areas occupied prior to human presence), and their spatial variation in abundance reflects vegetation productivity. Independent of vegetation productivity, however, recently recolonized areas have lower reindeer densities than areas not subject to past extirpation. This suggests that recovery from past overharvesting is still in progress. These incompletely recovered areas are potential targets for increased monitoring frequency and maintaining strict conservation to follow the Svalbard management goal (i.e., virtually untouched wilderness areas). Because of such ongoing recolonization, possibly combined with vegetation greening effects of recent warming, our status estimate of Svalbard reindeer abundance (22,435 [95% CI = 21,452–23,425]) is more than twice a previous estimate based on opportunistic counts. Thus, although our study demonstrates the successful outcome of strict harvesting control implemented a century ago, current and future population trajectories are likely shaped by climate change. © 2019 The Authors. Journal of Wildlife Management Published by Wiley Periodicals, Inc. on behalf of The Wildlife Society.

Adaptive Change in Wild Reindeer Seasonal Migrations in the Taimyr Peninsula

As the largest in the world the Taimyr population of wild reindeer displays pronounced seasonal migrations from forest zone to tundra for fawning in spring and return motion in fall. These motions are characterized with dynamics varying from year to year. Evidences of experience suggest that migration course cannot yet be interrupted or curtailed with artificial constructions or anthropogenic disturbance. By results of long-term observations carried out by one of the authors during 20 years, migration timing and speed were related to current ambient temperature and varied from year to year. As foreseen temperature rise happens more intensively inArcticthan upon an average through the Planet and is higher overland than it is over ocean it must apparently exert influence on the pattern of reindeer migrations. We hold that this phenomenon consists with changes in migration activity for recent decades and manifests increasing all-year-round separate reindeer groups presence in tundra. Some of these groups are registered and presented on the skeleton map. In the light of current climatic trend the ecological mechanism of migrations decrease should be grounded on reindeer bioenergetics and derived from ecological function of their migrations. Energy expenditures for far movements are getting less appropriate and the proportion of total heads staying in tundra zone all-year-round will increase. Available bioenergetics parameters and the simple model let to make a prediction. In the end we propose some preventive conservation arrangements to secure the mass heads of wild reindeer staying in tundra against adverse factors, mainly pending anthropogenic.

Polymorphism of the mtDNA Control Region in Reindeer (Rangifer tarandus) from the Mainland of the Northeastern Part of European Russia

Based on an analysis of the polymorphism of nucleotide sequences (n = 103) of the hypervariable fragment of the mtDNA control region (D-loop), the genetic diversity of wild and domestic reindeer from the mainland of the European Northeast of Russia (eastern parts of Arkhangelsk oblast, Komi Republic, and the Nenets Autonomous Okrug) was studied. Relatively high values of genetic diversity indices were detected. Phylogenetic analysis showed close relationships between reindeer of the study region and those of the tundra zone of Siberia. The influence of domestic reindeer on the formation of the genetic diversity of the wild reindeer was considered as negligible. Genetic lines belonging to an extinct group of forest reindeer from the Nizhny Novgorod region were found among the modern groups of reindeer from the European Northeast of Russia.

Rumen and Cecum Microbiomes in Reindeer (Rangifer tarandus tarandus) Are Changed in Response to a Lichen Diet and May Affect Enteric Methane Emissions.

Reindeer (Rangifer tarandus tarandus) are large Holarctic herbivores whose heterogeneous diet has led to the development of a unique gastrointestinal microbiota, essential for the digestion of arctic flora, which may include a large proportion of lichens during winter. Lichens are rich in plant secondary metabolites, which may affect members of the gut microbial consortium, such as the methane-producing methanogenic archaea. Little is known about the effect of lichen consumption on the rumen and cecum microbiotas and how this may affect methanogenesis in reindeer. Here, we examined the effects of dietary lichens on the reindeer gut microbiota, especially methanogens. Samples from the rumen and cecum were collected from two groups of reindeer, fed either lichens (Ld: n = 4), or a standard pelleted feed (Pd: n = 3). Microbial densities (methanogens, bacteria and protozoa) were quantified using quantitative real-time PCR and methanogen and bacterial diversities were determined by 454 pyrosequencing of the 16S rRNA genes.In general, the density of methanogens were not significantly affected (p>0.05) by the intake of lichens. Methanobrevibacter constituted the main archaeal genus (>95% of reads), with Mbr. thaueri CW as the dominant species in both groups of reindeer. Bacteria belonging to the uncharacterized Ruminococcaceae and the genus Prevotella were the dominant phylotypes in the rumen and cecum, in both diets (ranging between 16–38% total sequences). Bacteria belonging to the genus Ruminococcus (3.5% to 0.6%; p = 0.001) and uncharacterized phylotypes within the order Bacteroidales (8.4% to 1.3%; p = 0.027), were significantly decreased in the rumen of lichen-fed reindeer, but not in the cecum (p = 0.2 and p = 0.087, respectively). UniFrac-based analyses showed archaeal and bacterial libraries were significantly different between diets, in both the cecum and the rumen (vegan::Adonis: pseudo-F<0.05). Based upon previous literature, we suggest that the altered methanogen and bacterial profiles may account for expected lower methane emissions from lichen-fed reindeer.

Entheseal Changes in Free‐Ranging Versus Zoo Reindeer—Observing Activity Status of Reindeer

AbstractWe evaluate whether entheseal changes (EC) can be used to reconstruct activity among reindeer to study its domestication. Humans influence reindeer activity patterns through corralling, which renders them less mobile than free‐ranging reindeer and through use as draught animals, which can result in overuse of certain muscles. There is also variation within free‐ranging reindeer in baseline activity levels due to environmental factors. Other sources of variation at entheses include age, sex, pathology, size, and genetic disposition. Here we examine if there are differences in the entheses between zoo versus free‐ranging reindeer. We recorded the entheses of reindeer long bones using a modified EC scoring system. Weight effects were accounted for by performing analyses separately for specimens under and over 95 kg, but unfortunately age information was lacking. We found that several flexor muscle insertion sites in the ulna were more developed among free‐ranging reindeer. This difference is likely due to feeding behaviour. The free‐ranging animals were digging for lichen from under the snow whereas the zoo reindeer were fed by their keepers. This difference in entheses, however, was found to be significant only among the heavier reindeer. Among the zoo reindeer, the insertion for Subscapularis muscle was more developed, possibly due to increased time spent immobile with the shoulder‐bracing muscle apparatus activated. This difference was significant among the heavier deer and nearly statistically significant among the lighter weight reindeer. Domesticated Siberian draught reindeer fell between zoo and free‐ranging reindeer in several tibial entheses. According to these results, some forelimb entheses may be useful to study differences in mobility and feeding patterns between groups of reindeer. Copyright © 2014 John Wiley &amp; Sons, Ltd.

The reindeer abomasal nematode (Ostertagia gruehneri) is naturally transmitted to sheep when sharing pastures.

The increasing number of sheep (Ovis aries) in northern Finland, often alternately corralled with winter-fed reindeer (Rangifer tarandus tarandus), creates potential for cross-infection of gastrointestinal nematodes. The aim of this study was to elucidate this possibility with 43 animals. Eleven reindeer and 8 sheep had shared a corral by turns, reindeer during winters, and sheep in summers. Another 12 reindeer had no known contact with sheep. Twelve sheep had no close contact to other ruminants. Both reindeer groups were free-ranging during summers. During slaughter in September to November, 2003, abomasa and parts of intestines were collected. Gastrointestinal nematodes were counted and identified. The species found were the following: in reindeer, Ostertagia gruehneri/Ostertagia arctica, Mazamastrongylus dagestanica, Nematodirus tarandi, Nematodirella longissimespiculata and Bunostomum trigonocephalum; in sheep, Teladorsagia circumcincta/Teladorsagia trifurcata, O. gruehneri/O. arctica, Nematodirus filicollis and N. spathiger. In the sheep sharing corral with reindeer, the only abomasal nematode species found was O. gruehneri, a reindeer parasite. The generation interval of O. gruehneri in Finnish reindeer appears to be shorter than in Canadian Arctic caribou, where complete larval inhibition leading to only one generation yearly has been reported.

The ecologo-geographical framework for the protection and recovery of taiga reindeer populations within the Konda river basin (Western Siberia)

The key aspects of reindeer ecology within the Konda river basin are considered. The study revealed the factors governing the characteristics of calving reindeer pastures determined by the structure of forest-bog landscapes of a different generalization level. A deficit of such pastures is regarded as the factor of differentiation of reindeer groups with respect to migrants and residents. It is shown that the individual geocomplexes have a multifunctional role. Of particular significance among them are the aufeis glades with outcrops of salt-saturated groundwater, and the dark-coniferous forests along river valleys rich in epiphytic lichens (beard lichens).

Fibromatous lesions of antler velvet and haired skin in reindeer (Rangifer tarandus)

Fibromatous nodular lesions were observed on the antler skin of reindeer from four separate farms, and from the haired skin from a deer from a fifth farm. The aim of...

Cross-infection of gastrointestinal nematodes between winter corralled semi-domesticated reindeer (Rangifer tarandus tarandus) and sheep (Ovis aries)

The increasing number of sheep (Ovis aries) in the reindeer (Rangifer tarandus tarandus) herding area in North Finland and supplementary winter feeding of reindeer in corrals shared with sheep causes potential for cross-infection of gastrointestinal nematodes between reindeer and sheep. The aim of this study was to elucidate this potential. The study included 46 animals, of which 12 reindeer and 8 sheep had shared a corral. Twelve reindeer had no known contact with sheep. Both reindeer groups shared free ranging areas with wild moose (Alces alces). Two moose were included in this study, as were 12 sheep which had no contact with other ruminants. After slaughter in September-November abomasa and proximal small intestines were collected and examined for gastrointestinal nematodes. The parasites were collected, counted and identified. Following species were found in reindeer: Ostertagia gruehneri, Ostertagia arctica, Spiculopteragia dagestanica, Nematodirus tarandi, Nematodirella longissimespiculata and Bunostomum trigonocephalum. Sheep were infected with Teladorsagia circumcincta, Teladorsagia trifurcata, Ostertagia gruehneri, Ostertagia arctica, Nematodirus filicollis and Nematodirus spathiger. Spiculopteragia dagestanica and Ostertagia gruehneri were identified in moose. Ostertagia gruehneri, which is considered to be a reindeer parasite, was only found in the sheep that had shared a corral with reindeer. These sheep were not found to be infected with other abomasal nematodes. The reindeer that had shared a corral with sheep were not infected with nematodes usually having sheep as their primary host.

Effects of α-linolenic acid and eicosapentaenoic acid from linseed and algae, respectively, on reindeer (Rangifer tarandus tarandus L.) muscle fatty acid composition

In an earlier study, we concluded that pellet-fed reindeer could not elongate 18:3n − 3 (α-linolenic acid – ALA) sufficiently towards long-chain polyunsaturated fatty acids (LC PUFA) and need supplementation of LC PUFA. The present work investigated that the addition of n − 3 LC PUFA to feed in combination with ALA would increase the LC PUFA in the meat. Two groups of reindeer were fed pellets containing either linseed cake or linseed cake combined with algae (Nannochloropsis oculata) for 6 weeks before slaughter. Dietary n − 6/n − 3 ratio had a distinct influence on meat fatty acid (FA) composition when comparing linseed and linseed algae-fed animals with animals fed a conventional diet. Increased dietary proportions of ALA and eicosapentaenoic acid (EPA) increased these FA in muscle and docosapentaenoic acid (DPA) and docosahexaenoic acid in the polar lipid fraction compared to the conventional-fed animals. We concluded that an increased proportion of dietary EPA might lead to an increased elongation towards DPA in muscle. Algae and linseed are possible additives to reindeer feed in order to assure a similar valuable FA composition as in pasturing animals.

Dynamic Mutual Adaptation: Human-Animal Interaction in Reindeer Herding Pastoralism

Most of the existing anthropological literature that recognizes human-animal interaction as being at the core of nomadic pastoralism focuses on nomads as the only active agents of this interaction. Nomads interact with their animals by either adapting their actions to animal behavior or by changing this behavior in ways to suit them. Based on empirical material from two groups of reindeer herding nomads in northern Russia, we suggest that human-animal interaction in nomadic pastoralism can be better understood as being the result of a dynamic mutual behavioral adaptation. In the process of this adaptation, animals change their behavior in response to the herders’ actions, which in turn leads to a responsive change to herders’ patterns of actions, etc. We argue that this approach can account for the differences in both animal behavior and herding technologies across nomadic pastoralist cultures, as well as for some of the divergent developments within these cultures.

Threat of An Invasive Parasitic Fly, the Deer Ked (Lipoptena cervi), to the Reindeer (Rangifer Tarandus Tarandus): Experimental Infection and Treatment

Range expansion of ectoparasites can cause parasites to attack new host species. In these cases it is important for the parasite to be able to adapt to the new environment and to reproduce on the host. For the host, it is crucial to hinder successfully the development of long-lasting parasitic relationship. The deer ked (Lipoptena cervi) is a novel ectoparasite for northern cervids. We investigated if the deer ked can use the reindeer (Rangifer tarandus) as a host and, if it can, whether antiparasitic treatment against this parasite would be available. Three groups of reindeer were monitored: two groups of 6 reindeer were infected with 300 flies per each individual; a control group comprised 6 animals. One of the infected groups was treated with subcutaneous ivermectin. At the end of the experiment the infestation rate of the infected animals was low. The reindeer in the non-treated group had both live and dead deer keds and also a single pupa while the ivermectin-treated reindeer had only dead deer keds....

Habituation responses in wild reindeer exposed to recreational activities

Displacement is the effect most often predicted when recreational activities in wild reindeer (Rangifer tarandus tarandus) areas are discussed. Wild reindeer in Blefjell (225 km2) are exposed to humans more frequently than in Hardangervidda (8200 km2), from which the Blefjell herd originate. We recorded fright and flight response distances of groups of reindeer in both herds to a person directly approaching them on foot or skis during winter, summer, and autumn post-hunting and rutting season in 2004-2006. The response distances sight, alert, flight initiation and escape were shorter in Blefjell than in Hardangervidda while the probability of assessing the observer before flight tended to be greater in Blefjell. To test whether these results could be due to habituation or genetic influence of semi-domestic reindeer previously released in the Blefjell region, we compared the genetic variation of the Blefjell reindeer with previously reported variation in semi-domestic reindeer and in the wild reindeer from Hardangervidda. Microsatellite analyses revealed closer genetic ancestry of the Blefjell reindeer to the wild Hardangervidda reindeer and not to the semi-domestic reindeer at both the herd and the individual level. We conclude that the decreased flight responses in Blefjell reindeer appear to be a habituation response to frequent human encounters rather than traits inherited from a semi-domestic origin.

Effects of Recreational Cabins, Trails and Their Removal for Restoration of Reindeer Winter Ranges

Conservation efforts have secured the partial recovery of Europe's wild reindeer, although only in 24 separate fragments of their original range, now separated by resorts and roads. Full recovery of the original range will require restoration of migration routes across developed or disturbed areas. We analyzed distribution of around 3500 Rangifer tarandus tarandus (reindeer) during winters (1984–2005) in relation to 10 alpine resorts and prior to and following relocation of ski trails and cabins in Norway done to restore use of former habitat. Reindeer used areas within 15 km of resorts, which is less than expected based on the availability of habitat, most likely as a result of cross-country skiing activity surrounding the resorts, limiting their access to other ranges and historic migration corridors. Reindeer abundance declined and mean distance between reindeer groups and resorts increased with increasing resort size. No apparent habituation to resorts was observed during the 20-year study period. However, when ski trails and an associated tourist cabin were removed to restore access to historic habitat, reindeer moved into the area. No such change in reindeer distribution was observed in the 10 years preceding relocation, or at the other nine resorts where no such experiments were conducted. Regulation of human traffic, relocation of trails, and removal of infrastructure and cabins are apparently effective in restoring access to and use of historic ranges and migration routes. However, restoration of historic migration routes between ranges will likely require the removal of hundreds of recreational cabins in order to become effective.

Variation in gestation length among captive reindeer ( Rangifer tarandus tarandus)

An estimated 90% of reindeer females are mated in a 10- to 21-d interval and give birth in an equally synchronized manner. Reported gestation length in reindeer is highly variable (range, 203 to 240 d), almost twice the reindeer estrous cycle length. Previously, we identified a significant, negative relationship between gestation length and conception date in a small group of reindeer. In the current study, the negative relationship was investigated in a switchback design, where reindeer were divided into two groups synchronized for early and late mating over a 2-yr trial. Regression analysis of 11 paired observations produced a negative ( P < 0.001) association between gestation length and conception date (slope = − 0.31). Dam weight at breeding and prior to parturition, calf birth weight, and calf sex were not significant variables in the regression. Regression analysis of a larger data set from two University of Alaska Fairbanks reindeer herds, where conception date (verified by systemic progesterone) and gestation length were recorded (historical data set), supported previous conclusions ( n = 70; slope = −0.37; P < 0.001). Although the calf sex ratio did not differ with gestation length, there was a positive relationship ( r 2 = 0.19; P = 0.014) between male birth weight and gestation length in the larger data set. The negative relationship between conception date and gestation length enhanced calving synchrony, though the limits of gestation plasticity and underlying mechanisms are not clear. The potential role of photoperiod on early embryonic development is discussed.