On the tragedy of the commons: When predation and livestock loss may improve the economic lot of herders.
ABSTRACT: This paper studies the practice of semi-domestic reindeer (Rangifer t. tarandus) herding in Finnmark county in northern Norway. In this area, the Saami reindeer herders compete for space and grazing areas and keep large herds, while at the same time, the reindeer population is heavily exposed to carnivore predation by the lynx (Lynx lynx), the wolverine (Gulo gulo), and the golden eagle (Aquila chrysaetos). It is demonstrated that predation actually may improve the economic lot of livestock holders in this unmanaged local common setting. There are ecological as well as economic reasons as to why this happens. The ecological reason is that predation compensates for natural mortality; that is, increased predation reduces natural mortality, indicating that the net loss due to predation actually may be quite small. When predation reduces livestock density, the feeding conditions of the animals will improve, resulting in increased livestock weight and higher per animal slaughter value. At the same time, a smaller stock reduces the operating costs of the herders.
Project description:A major challenge in biodiversity conservation is to facilitate viable populations of large apex predators in ecosystems where they were recently driven to ecological extinction due to resource conflict with humans.Monetary compensation for losses of livestock due to predation is currently a key instrument to encourage human-carnivore coexistence. However, a lack of quantitative estimates of livestock losses due to predation leads to disagreement over the practice of compensation payments. This disagreement sustains the human-carnivore conflict.The level of depredation on year-round, free-ranging, semi-domestic reindeer by large carnivores in Fennoscandia has been widely debated over several decades. In Norway, the reindeer herders claim that lynx and wolverine cause losses of tens of thousands of animals annually and cause negative population growth in herds. Conversely, previous research has suggested that monetary predator compensation can result in positive population growth in the husbandry, with cascading negative effects of high grazer densities on the biodiversity in tundra ecosystems.We utilized a long-term, large-scale data set to estimate the relative importance of lynx and wolverine predation and density-dependent and climatic food limitation on claims for losses, recruitment and population growth rates in Norwegian reindeer husbandry.Claims of losses increased with increasing predator densities, but with no detectable effect on population growth rates. Density-dependent and climatic effects on claims of losses, recruitment and population growth rates were much stronger than the effects of variation in lynx and wolverine densities.Synthesis and applications. Our analysis provides a quantitative basis for predator compensation and estimation of the costs of reintroducing lynx and wolverine in areas with free-ranging semi-domestic reindeer. We outline a potential path for conflict management which involves adaptive monitoring programmes, open access to data, herder involvement and development of management strategy evaluation (MSE) models to disentangle complex responses including multiple stakeholders and individual harvester decisions.
Project description:Cooperation evolves on social networks and is shaped, in part, by norms: beliefs and expectations about the behaviour of others or of oneself. Networks of cooperative social partners and associated norms are vital for pastoralists, such as Saami reindeer herders in northern Norway. However, little is known quantitatively about how norms structure pastoralists' social networks or shape cooperation. Saami herders reported their social networks and participated in field experiments, allowing us to gauge the overlap between reported and emergent cooperation. We show that individuals' perceptions of reciprocal cooperation within their social networks exceeded actual reciprocity, although both occurred frequently and were concentrated within herding groups. Herders with more extensive cooperation networks received more rewards in an economic game. Although herders overestimated reciprocal helping, cooperation in this community was still extensive, suggesting that perceived norms potentially allow network structures promoting cooperation to emerge and be maintained.
Project description:Livestock depredation across the trans-Himalaya causes significant economic losses to pastoralist communities. Quantification of livestock predation and the assessment of variables associated with depredation are crucial for designing effective long-term mitigation measures. We investigated the patterns and factors of livestock depredation by snow leopards (<i>Panthera uncia</i>) using semi-structured questionnaires targeting herders in the Narphu valley of the Annapurna Conservation Area, Nepal. During the two years (2017/18 and 2018/19), 73.9% of the households interviewed (<i>n</i> = 65) lost livestock to snow leopards, with an annual average loss of two livestock per household. Of the total depredation attributed to snow leopards, 55.4% were yak (mainly female: 79%), 31.7% goat, 6.8% sheep, 3.2% horse and 2.8% cattle. Results from applying Generalized Linear Mixed Models (GLMMs) revealed the total number of livestock owned and the number of larger bodied livestock species as the main explanatory covariates explaining livestock depredation. Forty-one (41%) of all herders considered snow leopard's preference for domestic livestock as the main factor in livestock predation, whereas only 5% perceived poor herding practice as the main reason for the loss. Our study found poor and changing herding practices in the valley, whereby 71% herders reported careful herding as a solution to snow leopard depredation, and 15% of herders considered the complete extermination of snow leopards as the best solution to the problem. Tolerance levels and awareness among herders towards snow leopard conservation is increasing, mainly due to the Buddhist religion and strict law enforcement within this protected area. We recommend the effective implementation of a community-based livestock insurance scheme to compensate the economic loss of herders due to predation and improved herding practices as the recommended mitigation measures for ensuring livestock security and snow leopards' conservation in the valley.
Project description:Large carnivore conservation may be considered as successful in Sweden, as wolf (Canis lupus), lynx (Lynx lynx), brown bear (Ursus arctos), golden eagles (Aquila chrysaetos), and wolverine (Gulo gulo) populations have recovered from extinction or near extinction to viable populations during the last three decades. Particularly the wolf and lynx populations have returned at the cost of an increasing number of carnivore attacks on domestic livestock. To support coexistence between carnivores and livestock production, the Swedish authorities subsidise interventions to prevent or reduce the number of carnivore attacks. The most commonly used intervention is carnivore deterring fencing, and all livestock owners can apply for subsidies to build a fence. To receive reimbursement the fence must be approved by the authorities according to predefined criteria. An important part of any management aiming to be adaptive is evaluating interventions. In this paper we evaluate to what extent previously subsidised fences still meet the criteria 1-15 years after their approval. Of 296 fences that had received subsidies in the county of Värmland, 100 randomly selected fences were revisited in 2016. From this subsample 14% of the fences still met the initial criteria for subsidies. None of the fences that still fulfilled the criteria were more than 8 years old, whereas fences with identified failures occurred in all age groups. Of the 86 fences that failed to meet the criteria, construction failures were the most commonly occurring problem. Maintenance failures, wear and tear, only explain a minor part of the failures. To improve the quality of fencing, as well as the quality and longevity of the subsidies programme, there is a need for improved communication between authorities, and improved communication and support from the authorities to livestock producers before and during construction of fences, as well as more rigorous inspection when the fences are built.
Project description:INTRODUCTION:Geometrid moths and semi-domesticated reindeer are both herbivores which feed on birch leaves in the subarctic mountain birch forests in northern Fennoscandia. The caterpillars of autumnal and winter moths have episodic outbreaks, which can occasionally lead to extensive defoliation of birch forests. Earlier studies have shown that reindeer have a negative effect on the regeneration of defoliated birches by grazing and browsing their seedlings and sprouts. CASE DESCRIPTION:We interviewed 15 reindeer herders in the Kaldoaivi and Paistunturi herding co-operative in northernmost Finland in order to analyse their past, present and future views on the behaviour of moths and the growth of mountain birches. We investigate the behaviour of the two herbivores by combining the indigenous knowledge (IK) of Sámi herders with the results of relevant studies in biology and anthropology, applying niche construction theory (NCT) in doing so. DISCUSSION AND EVALUATION:In the first stage, the niche constructors (moths, reindeer, herders, mountain birch and other organisms) are looked upon as "equal constructors" of a shared niche. As changes unfold in their niche, their role changes from that of constructor to key constructor. The role and importance of niche constructors were different when nomadic pasture rotation was used than they are today under the herding co-operative system. Niche construction faced its most radical and permanent negative changes during the border closures that took place over the latter half of the 19(th) century. The large-scale nomadic life among the Sámi herders, who migrated between Finland and Norway, came to an end. This phase was followed by stationary herding, which diminished the possibilities of reindeer to look for various environmental affordances. Difficult snow conditions or birch defoliation caused by moth outbreaks made the situation worse than before. Eventually reindeer became key constructors, together with moth larvae, leading to negative ecological inheritance that forced herders to use new, adaptive herding practices. CONCLUSIONS:Both the scientific data and the IK of herders highlight the roles of reindeer and herders as continuous key constructors of the focal niche, one which stands to be modified in more heterogenic ways than earlier due to global warming and hence will result in new ecological inheritance.
Project description:The study of competition and coexistence among similar interacting species has long been considered a cornerstone in evolutionary and community ecology. However, understanding coexistence remains a challenge. Using two similar and sympatric competing large carnivores, Eurasian lynx and wolverines, we tested the hypotheses that tracking among heterospecifics and reactive responses to potential risk decreases the probability of an agonistic encounter when predators access shared food resources, thus facilitating coexistence. Lynx and wolverines actively avoided each other, with the degree of avoidance being greater for simultaneous than time-delayed predator locations. Wolverines reacted to the presence of lynx at relatively short distances (mean: 383 m). In general, lynx stayed longer, and were more stationary, around reindeer carcasses than wolverines. However, when both predators were present at the same time around a carcass, lynx shortened their visits, while wolverine behavior did not change. Our results support the idea that risk avoidance is a reactive, rather than a predictive, process. Since wolverines have adapted to coexist with lynx, exploiting lynx-killed reindeer carcasses while avoiding potential encounters, the combined presence of both predators may reduce wolverine kill rate and thus the total impact of these predators on semi-domestic reindeer in Scandinavia. Consequently, population management directed at lynx may affect wolverine populations and human-wolverine conflicts.
Project description:Hypoderma tarandi causes myiasis in reindeer and caribou (Rangifer tarandus spp.) in most northern hemisphere regions where these animals live. We report a series of 39 human myiasis cases caused by H. tarandi in Norway from 2011 to 2016. Thirty-two were residents of Finnmark, the northernmost county of Norway, one a visitor to Finnmark, and six lived in other counties of Norway where reindeer live. Clinical manifestations involved migratory dermal swellings of the face and head, enlargement of regional lymph nodes, and periorbital oedema, with or without eosinophilia. Most cases of human myiasis are seen in tropical and subtropical countries, and in tourists returning from such areas. Our findings demonstrate that myiasis caused by H. tarandi is more common than previously thought. Healthcare professionals in regions where there is a likelihood of human infestation with H. tarandi (regions populated by reindeer), or treating returning travellers, should be aware of the condition. All clinicians are advised to obtain a detailed travel history when assessing patients with migratory dermal swellings. On clinical suspicion, ivermectin should be given to prevent larval invasion of the eye (ophthalmomyiasis). Since H. tarandi oviposits on hair, we suggest wearing a hat as a prevention measure.
Project description:Analysing the effect of pastoral risk management strategies provides insights into a system of subsistence that have persevered in marginal areas for hundreds to thousands of years and may shed light into the future of around 200 million households in the face of climate change. This study investigated the efficiency of herd accumulation as a buffer strategy by analysing changes in livestock holdings during an environmental crisis in the Saami reindeer husbandry in Norway. We found a positive relationship between: (1) pre- and post-collapse herd size; and (2) pre-collapse herd size and the number of animals lost during the collapse, indicating that herd accumulation is an effective but costly strategy. Policies that fail to incorporate the risk-beneficial aspect of herd accumulation will have a limited effect and may indeed fail entirely. In the context of climate change, official policies that incorporate pastoral risk management strategies may be the only solution for ensuring their continued existence.
Project description:Although there is little doubt that the domestication of mammals was instrumental for the modernization of human societies, even basic features of the path towards domestication remain largely unresolved for many species. Reindeer are considered to be in the early phase of domestication with wild and domestic herds still coexisting widely across Eurasia. This provides a unique model system for understanding how the early domestication process may have taken place. We analysed mitochondrial sequences and nuclear microsatellites in domestic and wild herds throughout Eurasia to address the origin of reindeer herding and domestication history. Our data demonstrate independent origins of domestic reindeer in Russia and Fennoscandia. This implies that the Saami people of Fennoscandia domesticated their own reindeer independently of the indigenous cultures in western Russia. We also found that augmentation of local reindeer herds by crossing with wild animals has been common. However, some wild reindeer populations have not contributed to the domestic gene pool, suggesting variation in domestication potential among populations. These differences may explain why geographically isolated indigenous groups have been able to make the technological shift from mobile hunting to large-scale reindeer pastoralism independently.
Project description:Reindeer herding in Sweden is a form of pastoralism practised by the indigenous Sámi population. The economy is mainly based on meat production. Herd size is generally regulated by harvest in order not to overuse grazing ranges and keep a productive herd. Nonetheless, herd growth and room for harvest is currently small in many areas. Negative herd growth and low harvest rate were observed in one of two herds in a reindeer herding community in Central Sweden. The herds (A and B) used the same ranges from April until the autumn gathering in October-December, but were separated on different ranges over winter. Analyses of capture-recapture for 723 adult female reindeer over five years (2007-2012) revealed high annual losses (7.1% and 18.4%, for herd A and B respectively). A continuing decline in the total reindeer number in herd B demonstrated an inability to maintain the herd size in spite of a very small harvest. An estimated breakpoint for when herd size cannot be kept stable confirmed that the observed female mortality rate in herd B represented a state of herd collapse. Lower calving success in herd B compared to A indicated differences in winter foraging conditions. However, we found only minor differences in animal body condition between the herds in autumn. We found no evidence that a lower autumn body mass generally increased the risk for a female of dying from one autumn to the next. We conclude that the prime driver of the on-going collapse of herd B is not high animal density or poor body condition. Accidents or disease seem unlikely as major causes of mortality. Predation, primarily by lynx and wolverine, appears to be the most plausible reason for the high female mortality and state of collapse in the studied reindeer herding community.