Semi-domesticated Reindeer Research Articles

Experiences with live-capture and radio collaring of lynx Lynx lynx in Norway

Lynx have been captured for radio-collaring as part of three research projects in Norway between 1987 and 1996. Box traps, padded leghold traps, foot snares, combinations of foot snares and leghold traps, chasing animals up trees, catching neonates at lairs, and darting individuals while crossing roads have all been used to capture individuals. Mortality was particularly high (2 of 3 died) in the first project in Aust-Agder and Nord-Trøndelag (1987 - 88). Methodological improvements reduced this mortality rate to one lynx of 17 (6%) in Nord-Trøndelag (1994 - 96) and two of 17 (12%) in Hedmark (1995 - 96). Lessons from these accidents should reduce future mortality even further. Leghold traps and foot snares placed around a carcass of a prey animal killed by the lynx are far more effective than box traps, but maintain a higher risk of injuries. Lynx appeared more likely to return to roe deer carcasses than those of semi-domestic reindeer. There was no selection for lighter lynx. It is important to reduce the time-span between capture and immobilisation to lower the risk of injuries. It is recommended to avoid capturing and immobilising lynx at extremely low or high temperatures. Non-target animals getting caught can pose a minor problem when leghold traps stay open for longer periods.

Eavttut ja hástalusat boazodollui Norggas, Ruoŧas ja Suomas

This report is based on the book "Reindeer Husbandry and Global Environmental Change - pastoralism in Fennoscandia". The book, which was published in 2022, brings together previous and new research compiled within a Nordic collaboration project, ReiGN (Reindeer husbandry in a Globalizing North), funded by NordForsk during the years 2016 – 2021. Grants from NordForsk also funded this report. The report, published in Swedish, Norwegian, Finnish and North Sámi, summarizes some of the main results from the book. In nine chapters it describes how reindeer herding is affected by climate change, the continuous loss of reindeer grazing land and other external factors that together represent large challenges for reindeer, reindeer herders and the reindeer herding community as a whole. The report contains perspectives from many different research areas. Each chapter in the report has one or more references and links to chapters in the above mentioned book, which is freely available online (https://doi.org/10.4324/9781003118565). The chapters in the report cover a range of different topics, like present and historical reindeer herding (Chapter 1), the genetic background of the semi-domesticated reindeer (Chapter 2), how reindeer ranges are used and how they are affected by climate change and expanding industrial development (Chapter 3), possibilities for adaptation to a warmer climate (Chapter 4), impact of large predators (Chapter 5), external and internal governance (Chapter 6), reindeer herding as subsistence (Chapter 7), the role of supplementary feeding (Chapter 8), and reindeer health and diseases in a climate perspective (Chapter 9). The report ends with some reflections over the present situation and future perspectives for reindeer herding. The report is aimed at herders and managers, as well as other land users, authorities and policymakers who deal with natural resource management, climate and environmental issues or other matters related to reindeer herding and the use of land and water within the reindeer herding area. Rangifer Report No 21 is the North Sámi version of the report. Reports in Swedish and Norwegian have already been published as Rangifer Report No 16 and No 17, respectively. A Finnish version is published as a following number of Rangifer Report.

The content of reindeer male vocalisations: acoustic cues to age and size

ABSTRACT Some acoustic parameters of animal vocalisations have been shown to reliably indicate male quality and play a role in mate and rival assessment. Reindeer possess a peculiar vocal tract anatomy involving a laryngeal air sac which probably acts as an additional filter, making it a candidate species for novel investigations in the field of bioacoustics. We investigated whether some acoustic parameters of male rutting vocalisations were good indicators of age and body weight (used as an index for body size). We did this by performing acoustic analyses using recordings collected from a semi-domesticated reindeer population in northern Finland. We found the age of subadult males (aged 2.5–4.5 years) to be negatively correlated with formant F3 and formant spacing, suggesting that their vocalisations convey information on the caller’s age. Individual formant frequencies were not affected by male body weight, but formant spacing was lower in heavier males. Despite the presence of the laryngeal air sac, formant spacing seems to be an acoustic parameter influencing mate and rival assessment in reindeer as it gives an honest indication of male body size. We discuss the importance of reliable acoustic cues to quality indices in sexual selection contexts.

Assessing freedom from chronic wasting disease in semi-domesticated reindeer in Norway and Sweden

Establishing freedom from disease is a key component of surveillance and may have direct consequences for trade and economy. Transboundary populations pose challenges in terms of variable legislation, efforts, and data availability between countries, often limiting surveillance efficiency. Chronic wasting disease (CWD) is a contagious prion disease of cervids. The long incubation period and slow initial epidemic growth make it notoriously difficult to detect CWD in the early phase of an epidemic. The recent emergence of CWD in wild reindeer in Norway poses a threat to approximately 250,000 semi-domesticated reindeer in Norway and 250,000 in Sweden, including transboundary populations. Here, we provide a first analysis of surveillance data (2016–2022) from all reindeer districts in Norway and Sweden to determine the probability of freedom from CWD infection. During the six years, 6017 semi-domesticated reindeer were tested in Sweden and 51,974 in Norway. Most samples came from healthy slaughtered animals (low risk). Reindeer use large and remote areas and (high risk) samples from fallen stock and animals with clinical signs were difficult to obtain. A scenario tree model was run for seven different set of values for the input parameters (design prevalence within and between districts, probability of introduction, and relative risks) to determine the effect on surveillance sensitivity. At the national level, the mean probability of disease freedom was 59.0 % in Sweden and 87.0 % in Norway by 2021. The most marked effect on sensitivity was varying the design prevalence both within and between districts. Uncertainty about relative risk ratios affected sensitivity for Sweden more than for Norway, due to the higher proportion of animals in the high-risk group in the former (13.8 % vs. 2.1 %, respectively). A probability of disease freedom of 90 % or higher was reached in 8.2 % of the 49 districts in Sweden and 43.5 % of the 46 districts in Norway for a design prevalence of 0.5 %. The probability of freedom remained below 60 % in 29 districts (59.2 %) in Sweden and 10 districts (21.7 %) in Norway. At the national level, only Norway had a sufficiently large number of samples to reach a probability of more than 95 % of disease freedom within a period of 10 years. Our cross-border assessment forms an important knowledge base for designing future surveillance efforts depending on the spatial pattern of prevalence of CWD and risk of spread.

Forutsetninger og utfordringer for reindrifta i Norge, Sverige og Finland

This report is based on the book "Reindeer Husbandry and Global Environmental Change - pastoralism in Fennoscandia". The book, which was published in 2022, brings together previous and new research compiled within a Nordic collaboration project, ReiGN (Reindeer husbandry in a Globalizing North), funded by NordForsk during the years 2016 – 2021. Grants from NordForsk also funded this report. The report, published in Swedish, Norwegian, Finnish and North Sámi, summarizes some of the main results from the book. In nine chapters it describes how reindeer herding is affected by climate change, the continuous loss of reindeer grazing land and other external factors that together represent large challenges for reindeer, reindeer herders and the reindeer herding community as a whole. The report contains perspectives from many different research areas. Each chapter in the report has one or more references and links to chapters in the above mentioned book, which is freely available online (https://doi.org/10.4324/9781003118565). The chapters in the report cover a range of different topics, like present and historical reindeer herding (Chapter 1), the genetic background of the semi-domesticated reindeer (Chapter 2), how reindeer ranges are used and how they are affected by climate change and expanding industrial development (Chapter 3), possibilities for adaptation to a warmer climate (Chapter 4), impact of large predators (Chapter 5), external and internal governance (Chapter 6), reindeer herding as subsistence (Chapter 7), the role of supplementary feeding (Chapter 8), and reindeer health and diseases in a climate perspective (Chapter 9). The report ends with some reflections over the present situation and future perspectives for reindeer herding. The report is aimed at herders and managers, as well as other land users, authorities and policymakers who deal with natural resource management, climate and environmental issues or other matters related to reindeer herding and the use of land and water within the reindeer herding area. Rangifer Report No 17 is the Norwegian version of the report. A Swedish version has already been published as Rangifer Report No 16. Reports in Finnish and North Sámi are published as following numbers of Rangifer Report.

Necropsy findings, meat control pathology and causes of loss in semi-domesticated reindeer (Rangifer tarandus tarandus) in northern Norway

BackgroundReindeer herding in Norway is based on traditional Sámi pastoralism with the animals free ranging throughout the year. The animals move over large areas in varying terrain and often in challenging weather conditions. Winter crises, such as difficult grazing conditions caused by icing or large amounts of snow, are survival bottlenecks for reindeer. Calves are especially vulnerable, and many may die from starvation during winter crises. Predation and starvation are the predominant narratives to explain losses, however, carcasses are difficult to find and often little remains after scavenging and decay. Documentation of the causes of death is therefore scarce.ResultsIn this study, we investigated the cause of reindeer mortality in Troms and Finnmark, Nordland and Trøndelag during 2017–2019. Necropsies (n = 125) and organ investigation (n = 13) were performed to document cause of death. Body condition was evaluated using visual fat score and bone marrow fat index. A wide range of causes of death was detected. The diagnoses were categorized into the following main categories: predation (n = 40), emaciation (n = 35), infectious disease (n = 20), trauma (n = 11), feeding related disease (n = 5), neoplasia (n = 4), others (n = 6) and unknown (n = 17). Co-morbidities were seen in a number of diagnoses (n = 16). Reindeer herders are entitled to economic compensation for reindeer killed by endangered predators, but a lack of documentation leads to a gap between the amount of compensation requested and what is awarded. An important finding of our study was that predators, during winter, killed animals in good as well as poor body condition. Emaciation was also shown to be associated with infectious diseases, and not only attributable to winter grazing conditions.ConclusionsThis study highlights the importance of examining dead reindeer to gain knowledge about why they die on winter pasture. The work presented herein also shows the feasibility and value of increased documentation of reindeer losses during winter.

Evidence suggesting that reindeer mothers allonurse according to the direct reciprocity and generalized reciprocity decision rules

Allonursing is the nursing of the offspring of other mothers. Cooperation is an emergent property of evolved decision rules. Cooperation can be explained by at least three evolved decision rules: 1) direct reciprocity, i.e. help someone who previously helped you, 2) kin discrimination, i.e. preferentially direct help to kin than to non-kin, and 3) generalized reciprocity, i.e. help anyone if helped by someone. We assessed if semi-domesticated reindeer, Rangifer tarandus, mothers allonursed according to the decision rules of direct reciprocity, generalized reciprocity and kin discrimination over 2 years. To assess if reindeer mothers allonursed according to the direct reciprocity decision rule, we predicted that mothers should give more help to those who previously helped them more often. To assess if reindeer mothers allonursed according to the kin discrimination decision rule, we predicted that help given should increase as pairwise genetic relatedness increased. To assess if reindeer mothers allonursed according to the generalized reciprocity decision rule, we predicted that the overall number of help given by reindeer mothers should increase as the overall number of help received by reindeer mothers increased. The number of help given i) increased as the number of help received from the same partner increased in the 2012 group but not in both 2013 groups, ii) was not influenced by relatedness, and iii) was not influenced by an interaction between the number of help received from the same partner and relatedness. iv) The overall number of help given increased as the overall number of help received increased. The results did not support the prediction that reindeer mothers allonursed according to the kin discrimination decision rule. The results suggest that reindeer mothers may allonurse according to the direct reciprocity and generalized reciprocity decision rules.

Toxoplasma gondii seroprevalence in reindeer (Rangifer tarandus tarandus L.) in northern Sweden: a cross-sectional study from 2014

BackgroundToxoplasma gondii is a parasitic protozoan that can infect a wide range of warm-blooded animals, including humans. The infection with T. gondii, is of particular concern due to its potential impact on human and animal health. In Sweden, semi-domesticated reindeer (Rangifer tarandus tarandus L.) is an important species both economically and culturally, but susceptibility to Toxoplasma infection and seroprevalence in reindeer herds remain relatively understudied.ResultsA total of 528 reindeer, sampled at two slaughterhouses in Sweden in 2014, were investigated for antibodies to T. gondii. Specific antibodies to T. gondii were found in 5 of 209 (2.3%) tested adult reindeer and in 6 of 308 (1.9%) tested calves, giving an apparent total prevalence of 2.1% (95% confidence interval 1.1–3.8%). None of four putative risk factors studied (sex, age, type of grazing area, county) were statistically associated with T. gondii seroprevalence.ConclusionsSwedish semi-domesticated reindeer are exposed to T. gondii and may harbour infectious tissue cysts. To mitigate the risk of T. gondii infection in consumers, reindeer meat should be frozen or cooked thoroughly before consumption. The global climate change may influence the seroprevalence and possible associated risk factors for T. gondii in reindeer. To be able to manage the risk and get better advice to the consumers there is a need for further investigations covering the whole spectra of herding conditions for reindeer.

Förutsättningar och utmaningar för renskötseln i Norge, Sverige och Finland

This report is based on the book "Reindeer Husbandry and Global Environmental Change - pastoralism in Fennoscandia". The book, which was published in 2022, brings together previous and new research compiled within a Nordic collaboration project, ReiGN (Reindeer husbandry in a Globalizing North), funded by NordForsk during the years 2016 – 2021. Grants from NordForsk also funded this report. The report, published in Swedish, Norwegian, Finnish and North Sámi, summarizes some of the main results from the book. In nine chapters it describes how reindeer herding is affected by climate change, the continuous loss of reindeer grazing land and other external factors that together represent large challenges for reindeer, reindeer herders and the reindeer herding community as a whole. The report contains perspectives from many different research areas. Each chapter in the report has one or more references and links to chapters in the above mentioned book, which is freely available online (https://doi.org/10.4324/9781003118565). The chapters in the report cover a range of different topics, like present and historical reindeer herding (Chapter 1), the genetic background of the semi-domesticated reindeer (Chapter 2), how reindeer ranges are used and how they are affected by climate change and expanding industrial development (Chapter 3), possibilities for adaptation to a warmer climate (Chapter 4), impact of large predators (Chapter 5), external and internal governance (Chapter 6), reindeer herding as subsistence (Chapter 7), the role of supplementary feeding (Chapter 8), and reindeer health and diseases in a climate perspective (Chapter 9). The report ends with some reflections over the present situation and future perspectives for reindeer herding. The report is aimed at herders and managers, as well as other land users, authorities and policymakers who deal with natural resource management, climate and environmental issues or other matters related to reindeer herding and the use of land and water within the reindeer herding area. Rangifer Report No 16 is the Swedish version of the report. Reports in Norwegian, Finnish and North Sámi are published as following numbers of Rangifer Report.

Morphometrics highlights subspecies differentiation of continental (Rangifer t. tarandus) and insular (Rangifer t. platyrhynchus) Norwegian reindeer

Abstract Reindeer (Rangifer tarandus) is an emblematic species with several recognized subspecies. Two reindeer subspecies are present in Norway: the wild and semi-domestic European tundra reindeer (R. tarandus tarandus) in continental Norway, and Svalbard reindeer (R. tarandus platyrhynchus) endemic to this archipelago. The main aim of this paper is to give a descriptive and quantified analysis of the modern wild reindeer morphological diversity. The morphometric variation was quantified, based on 262 adult specimens of both sexes, by both linear measurements, analysed through log shape ratio computed from post-cranial bones and teeth measurements, and landmarks and sliding semi-landmarks based geometric morphometrics (GMM) to quantify molars size and shape. All anatomical parts (teeth, metatarsals, metacarpals) highlighted differences between the continental and insular subspecies. Our main results pointed out morphometrics characteristics of nowadays reindeer subspecies, like differences in proportions between the size of metapodials or lower cheek teeth with the body size, that could be of great interest for archaeozoological research.

Infectious keratoconjunctivitis in semi-domesticated reindeer (Rangifer tarandus tarandus): a questionnaire-based study among reindeer herders in Norway and Sweden

BackgroundThe effects of climate change, loss of pastureland to other land usage and presence of large carnivores are the main reasons for the increase in supplementary feeding of semi-domesticated reindeer (Rangifer tarandus tarandus) in Fennoscandia over the last decades. Feeding might expose reindeer to stress and increased animal-to-animal contact, leading to an increased risk of infectious disease transmission, such as infectious keratoconjunctivitis (IKC). As it can develop rapidly and be very painful, IKC is described as an important animal welfare concern and a potential source of economic loss. The aim of this study was to investigate the current presence of IKC and potential associations between IKC and supplementary feeding through an online questionnaire survey, distributed among reindeer herders in Norway and Sweden in 2021.ResultsSeventy-six reindeer herders (33 from Norway and 43 from Sweden) responded to the questionnaire, representing 6% and 4% of the registered reindeer herding groups in Norway and Sweden, respectively. Infectious keratoconjunctivitis was common, with 54 (71%) of the 76 herders that responded having observed clinical signs during the past 10 years. These signs were mainly observed as increased lacrimation, causing “wet cheeks”, but also as keratitis and conjunctivitis. Autumn and winter were the seasons in which IKC was observed most. The herders reported several measures, such as slaughter and isolation of affected reindeer, to counteract the spread of disease. The herding year 2019/2020 was associated with reports of outbreaks of IKC in herds as well as being the herding year where most herders (80%) had performed supplementary feeding. A significant association was found between IKC and feeding performed in an enclosure (odds ratio = 15.20), while feeding on free-range areas had a non-significant, negative, relationship with the appearance of IKC outbreaks (odds ratio = 0.29). Finally, there was a trend in the data suggesting that IKC affected calves especially.ConclusionsInfectious keratoconjunctivitis is a common disease, mainly observed in winter and autumn. It usually has mild to moderately severe clinical signs. Our results imply that IKC is associated with stress and feeding situations and that calves might be more susceptible than adults, however, this needs to be confirmed with further studies, preferably at an individual animal level.

Serological screening for tick-borne encephalitis virus in eight Norwegian herds of semi-domesticated reindeer (Rangifer tarandus tarandus).

Tick-borne encephalitis virus (TBEV) is found in Ixodes ricinus ticks throughout the area where viable tick populations exist. In Norway, TBEV is found in I. ricinus from the south coast until Brønnøy municipality in Nordland County and the range of the vector is expanding due to changes in climate, vegetation, host animals and environmental conditions. TBEV might thus have the potential to establish in new areas when I. ricinus expand its geographical distribution. At present, there is little knowledge on the status of the virus in high-altitude areas of inland regions in Norway. It has previously been indicated that reindeer may be an important sentinel species and indicator of the spread of ticks and TBEV in high-altitude regions. In this study, 408 semi-domesticated Eurasian tundra reindeer (Rangifer tarandus tarandus) from eight herds, from Tana in Troms and Finnmark County in northern Norway to Filefjell in Innlandet and Viken Counties in southern Norway, were screened for TBEV antibodies using a commercial enzyme-linked immunosorbent assay (ELISA). We found 16 TBEV reactive reindeer samples by ELISA; however, these results could not be confirmed by the serum neutralization test (SNT). This could indicate that a flavivirusand not necessarily TBEV, may be circulating among Norwegian semi-domesticated reindeer. The results also indicate that TBEV was not enzootic in Norwegian semi-domesticated reindeer in 2013-2015. This knowledge is important as an information base for future TBEV and flavivirus surveillance in Norway.

Semi-domesticated reindeer avoid winter habitats with exotic tree species Pinus contorta

The introduction of exotic tree species can have profound effects on the native environment, including habitat use and movement patterns of animals, as well as becoming a management challenge for other land users. Here, we used GPS data from reindeer (Rangifer tarandus) and remote sensing measurements of lichen cover and soil moisture to assess the effects of the exotic lodgepole pine (Pinus contorta) on reindeer husbandry by the Indigenous Sámi in northern Sweden. We used locational data from 67 reindeer for three winters to analyze their habitat selection at the second-order selection (placement of home range in the landscape) and third-order selection (selection of sites within the home range) in relation to land cover class, terricolous lichen cover as measure of winter forage abundance, topographic features, and distance to roads. We also analyzed remotely sensed abundance of lichens in different forest types, and the association between these forest types and soil moisture as measure of suitability as lichen habitat. Compared to native P. sylvestris, we found that reindeer avoided stands with P. contorta where trees were higher than three meters. If P. contorta was the dominant tree species, reindeer were 60 % less likely to select these stands compared to stands with P. sylvestris, and 40 % less likely if P. contorta was less dominant at both orders of selection. We also found that reindeer selected areas with higher lichen cover. Lichen cover was lower in P. contorta stands compared to stands of the native P. sylvestris, even though P. contorta occurred mainly on dry soils usually favorable for terricolous lichens. We conclude that planting P. contorta on soils suitable for terricolous lichens is likely to reduce forage availability for reindeer and turn habitats earlier preferred by reindeer into avoided habitat, resulting in an overall reduction of winter grazing grounds. The effects of stands with P. contorta, albeit covering a comparatively small percentage of the reindeer husbandry area, need to be seen in context with generally declining terricolous lichen abundance due to land uses like forestry and other cumulative effects by external pressures on reindeer husbandry.

A serological screening for potential viral pathogens among semi-domesticated Eurasian tundra reindeer (Rangifer tarandus tarandus) in Finland

BackgroundReindeer herding and husbandry is a traditional and important livelihood in Fennoscandia, and about 200,000 semi-domesticated reindeer are herded in Finland. Climatic changes, leading to ice-locked winter pastures, and encroachment of pasture-land have led to changes in reindeer husbandry, increasing the extent of supplementary or full ration feeding, which has become very common in Finland. Keeping reindeer in corrals or gathering them at permanent feeding sites will increase nose-to-nose contact between animals and they may be exposed to poor hygienic conditions. This may impact the epidemiology of infectious diseases, such as viral infections. The aim of this study was to investigate Finnish semi-domesticated reindeer for exposure to viral pathogens. Blood samples were collected from 596 reindeer (358 calves, 238 adults) in 2015, from nine reindeer slaughterhouses, representing most of the reindeer herding regions in Finland. Plasma samples were investigated for antibodies against a selection of known and potential reindeer viral pathogens by using enzyme linked immunosorbent assays (ELISA).ResultsThe screening suggested that alphaherpesvirus and gammaherpesvirus (malignant catarrhal fever virus group; MCFV) were enzootic in the reindeer population, with a seroprevalence of 46.5% (range at slaughterhouse level 28.6–64.3%) and 29.0% (range 3.5–62.2%), respectively. Whereas the seroprevalence was significantly higher for alphaherpesvirus among adult reindeer (91.2%) as compared to calves (16.8%), no age difference was revealed for antibodies against gammaherpesvirus. For alphaherpesvirus, the seroprevalence in the northernmost region, having the highest animal density (animals/km2), was significantly higher (55.6%) as compared to the southernmost region (36.2%), whereas the seroprevalence pattern for gammaherpesvirus indicated the opposite, with 8.1% in the north and 50.0% in the south. Four reindeer (0.7%) had antibodies against Pestivirus, whereas no antibodies were detected against Bluetongue virus or Schmallenbergvirus.ConclusionsAlphaherpesvirus and gammaherpesvirus (MCFV) seems to be enzootic in the Finnish reindeer population, similar to other reindeer herds in Fennoscandia, whereas the exposure to Pestivirus was low compared to findings in Norway and Sweden. The ongoing changes in the reindeer herding industry necessitate knowledge on reindeer health and diseases that may impact animal welfare and health of reindeer as well as the economy of the reindeer herding industry.

A Screening for Virus Infections among Wild Eurasian Tundra Reindeer (Rangifer tarandus tarandus) in Iceland, 2017-2019.

A winter population of around 4000-5000 wild Eurasian tundra reindeer (Rangifer t. tarandus) in the eastern part of Iceland represents descendants from 35 semi-domesticated reindeer imported to Iceland from Finnmark county, Norway, in 1787. While previous studies have indicated that they host fewer parasite species as compared to reindeer in Fennoscandia, little information exists on their exposure to reindeer viral pathogens. The aim of this study was to investigate blood from hunted reindeer for antibodies against alphaherpesvirus and gammaherpesviruses (malignant catarrhal fever viruses, MCFV), pestivirus, bluetongue virus, and Schmallenberg virus, and to investigate nasal and oral mucosal membrane swab samples for the presence of parapoxvirus-specific DNA. Blood samples collected during the hunting seasons in 2017 (n = 40), 2018 (n = 103), and 2019 (n = 138) were tested for viral antibodies using enzyme-linked immunosorbent assays (ELISA). Screening for parapoxvirus DNA was conducted on swab samples from 181 reindeer by polymerase chain reaction (PCR), targeting the B2L and GIF genes. Antibodies against pestivirus were detected in two animals from 2017, and antibodies against MCFV were detected in two reindeer from 2018. No antibodies were detected against the other viruses tested. Parapoxvirus-specific DNA was detected in nasal swab samples from two animals sampled in 2019. This study suggests that the investigated viral infections are either not present or present at a low prevalence only, probably not representing a major health threat to this reindeer population. The lack of exposure to alphaherpesvirus, an enzootic pathogen in most investigated Rangifer populations, was unexpected.

Effects of Wind Power Development on Reindeer: Global Positioning System Monitoring and Herders’ Experience

Testing and documenting effects of wind farm (WF) infrastructure on wildlife are crucial considering increasing development throughout Scandinavia, especially for reindeer, which require large areas for grazing and are vulnerable to disturbances. We present results from 2011 to 2019 for semidomesticated reindeer tracked with Global Positioning System (GPS) transmitters, along with herders’ knowledge about reindeers’ habitat use and changes following WF development within the Raggonjarga reindeer district summer range in Finnmark, Norway. We tracked up to 36 females (ranging from 19 to 36 individuals per year), from their arrival in the study area in April to their departure in the end of October. We evaluated habitat use before, during, and after WF development at the home range and landscape scales. We also evaluated reindeer habitat use qualitatively based on semistructured interviews with local herders. The herders’ reported negative effects of the WF on reindeer, both on general habitat use and intrarange movements, resulting in less use of grazing areas surrounding the WF and increased workload for the herders. The GPS results partly support the herders’ experiences. We found negative effects of the WF at the landscape scale, except during summer, where the effect was positive. Results at the home range scale showed negative effects of the WF in spring and summer, but not autumn. Different results at different scales make identifying causality challenging, especially as yearly variation was also large. Different results for summer and autumn may relate to changes in herding activities and larger movement patterns, respectively. Similar and contrasting results from the two methods suggest a need for both sources of data in combination to understand and improve land management. Including herders’ knowledge to understand results from GPS data is thus crucial. We also suggest future studies focus on mechanisms behind behavioral changes to better understand cause-and-effect relationships and how effects can be mitigated.

Functional immune diversity in reindeer reveals a high Arctic population at risk

Climate changes the geographic range of both species as well as pathogens, causing a potential increase in the vulnerability of populations or species with limited genetic diversity. With advances in high throughput sequencing (HTS) technologies, we can now define functional expressed genetic diversity of wild species at a larger scale and identify populations at risk. Previous studies have used genomic DNA to define major histocompatibility complex (MHC) class II diversity in reindeer. Varying numbers of expressed genes found in many ungulates strongly argues for using cDNA in MHC typing strategies to ensure that diversity estimates relate to functional genes. We have used available reindeer genomes to identify candidate genes and established an HTS approach to define expressed MHC class I and class II diversity. To capture a broad diversity we included samples from wild reindeer from Southern Norway, semi-domesticated reindeer from Northern Norway and reindeer from the high Artic archipelago Svalbard. Our data show a medium MHC diversity in semi-domesticated and wild Norwegian mainland reindeer, and low MHC diversity reindeer in Svalbard reindeer. The low immune diversity in Svalbard reindeer provides a potential risk if the pathogenic pressure changes in response to altered environmental conditions due to climate change, or increased human-related activity.

Pharmacokinetics of a long-acting subcutaneous eprinomectin injection in semi-domesticated reindeer (Rangifer tarandus tarandus) – A pilot study

Reindeer (Rangifer tarandus tarandus) are exposed to the pathogenic parasitic nematode Elaphostrongylus rangiferi during grazing. The severity of disease is dose-dependent. Prophylactic anthelmintic treatment is needed to improve animal health and reindeer herding sustainability. Herds are traditionally only gathered once during the summer, requiring a drug with a persistent effect. In this study we investigated the suitability of long-acting eprinomectin, given as a single subcutaneous injection at 1 mg/kg bodyweight in adult reindeer and calves. Plasma and faeces concentrations were determined using ultra-high performance liquid chromatography high resolution mass spectrometry (UHPLC-HRMS). Plasma concentrations remained above the presumed effect level of 2 ng/mL for 80 days, demonstrating the drug’s potential. Pharmacokinetic parameters were compared to other species using allometric scaling. Calves and adults had slightly different profiles. No viable faecal nematode eggs were detected during treatment. Eprinomectin was measurable in the reindeer faeces up to 100 days, which is of environmental concern.

Winter condition variability decreases the economic sustainability of reindeer husbandry.

Wild and semidomesticated reindeer are one of the key species in Arctic and subarctic areas, and their population dynamics are closely tied to winter conditions. Difficult snow conditions have been found to decrease the calving success and survivability of reindeer, but the economic effects of variation in winter conditions on reindeer husbandry have not been studied. In this study, we combine state-of-the-art economic-ecological modeling with the analysis of annual reindeer management reports from Finland. These contain local knowledge of herding communities. We quantify the occurrence probabilities of different types of winters from annual management reports and analyze the effects of this variation in winter conditions on reindeer husbandry using an age- and sex-structured bioeconomic reindeer-lichen model. Our results show that difficult winters decrease the net revenues of reindeer husbandry. However, they also protect lichen pastures from grazing, thereby increasing future net revenues. Nonetheless, our solutions show that the variability of winter conditions overall decrease the net income of herders compared to constant winter conditions. Low lichen biomass appears to make reindeer management more sensitive to the effects of difficult winter conditions. We also found that it is economically sensible to use supplementary feeding during difficult winters, but the net revenues still decrease compared to average winters because of the high feeding costs. Overall, our analysis suggests that the increasing variability of winter conditions due to climate change will decrease net revenues in reindeer husbandry. This decrease will still occur even if the most extreme effects of climate change do not occur. This study shows that combining a state-of-the-art bioeconomic model and practitioner knowledge can bring compatible insights, ideas, results, and a bottom-up perspective to the discussion.

Brown bear predation on semi-domesticated reindeer and depredation compensations

The recovery and conservation of large carnivores can negatively impact the economy of traditional pastoralist societies, including indigenous reindeer ( Rangifer tarandus ) herding communities. Quantifying the magnitude of predation on livestock is critical to evaluating governmental carnivore compensation schemes. We collaborated with two Sámi herding communities in northern Sweden (2010–2012) to examine brown bear ( Ursus arctos ) predation patterns on semi-domesticated reindeer and quantify the economic impact of bear predation. Predation patterns were estimated by following 21 GPS proximity-collared bears and ~2500 transmitter-collared female reindeer during calving season. We calculated economic impact by multiplying the monetary value of reindeer by the expected number lost to bears. On average, bears killed 10.2 [8.6, 11.5] calves per bear, accounting for 39−62% of all calf mortality, while few adult reindeer were killed. Bear kill rates increased with time spent in the calving area, and varied widely by individual and reproductive status, e.g., females with cubs-of-the-year did not kill calves. Kill intervals increased over the parturition season, and were larger for sub-adults than adults. The mean reindeer calf predation rate was 16–27%, which resulted in an annual loss between ~€50,000 and ~€62,000 per herding group. Current compensation schemes for herding communities in Sweden are calculated as a fixed rate based on herding community land-area. The herding groups in our study were reimbursed for ~2% of realized monetary loss. Compensation schemes based on herding community area, rather than realized predation patterns, may be less effective at mitigating the economic impact of living with large carnivores.