Öje Danell

Reindeer in the Swedish Mountains: An Assessment of Grazing Impacts

Abstract During the last decade, several well-publicized grazing-related incidents of vegetation degradation have helped to form an official opinion of overutilization of some mountain areas and a concern that Swedish reindeer husbandry may not be ecologically sustainable. We examine these examples in a temporal and management perspective to assess the scale of impact on summer grazing grounds in the Swedish mountains. Long-term data on population dynamics of reindeer show no trend with fluctuations around 225 000 animals for the last century. Data on grazing effects from Långfjället (Dalarna) and Mittåkläppen (Härjedalen) are discussed in detail. We compare these data to the situation in Finnmark, Norway, and in northern Finland where reindeer husbandry in recent decades does not seem to have been ecologically sustainable. We conclude that large-scale overexploitation by reindeer in the Swedish mountains is not evident. However, strong grazing and trampling effects may be found around enclosures and fences.

Summer habitat preferences of GPS-collared reindeer Rangifer tarandus tarandus

Abstract Reindeer Rangifer tarandus tarandus husbandry in Sweden commonly uses the Scandinavian mountain chain as grazing area during the snow-free season and the coniferous forests in the east during winter. Current knowledge of habitat use by reindeer is primarily based on traditional or local knowledge, or on investigations carried out on wild reindeer and caribou in other parts of the world. We identified spatial and temporal habitat use of free-ranging semi-domesticated reindeer by following 48 GPS-equipped reindeer in three summer ranges in the Swedish reindeer herding area. The GPS equipment registered positions every hour or every second hour, during two snow-free seasons. The GPS-collared reindeer were randomly chosen from herds with several thousand animals. Estimated home-range utilisation distributions were used to fit resource utilisation functions (RUFs) including various topographical features, vegetation types, and the vicinity to water and hiking trails. The GPS-equipped reindeer used different parts of the range throughout the snow-free season. Preferred vegetation types were consistently meadows, grass heaths, and other heaths. Avoided vegetation types were all types of forests, sparsely vegetated areas, and bare rocks. The reindeer were seemingly indifferent to hiking trails within their home ranges, which, however, usually coincided with preferred vegetation types, but they avoided areas with houses and holiday huts during early summer. Later in the season, the reindeer preferred higher elevated areas where human constructions were sparse. The home ranges of the GPS-equipped reindeer overlapped considerably during early parts of the season, indicating a dense use of the range by the entire herds. Crowding within the herds appeared to make individual reindeer select non-optimal habitats. However, in our study, we found a non-significant tendency of less predictable individual home ranges when there were large range overlaps. Vegetation types, direction of slopes, time within the season and the possibilities of avoiding insect harassment appear to be key factors for predicting valuable reindeer habitats in novel areas in a land management context.

Insect avoidance may override human disturbances in reindeer habitat selection

Habitat selection of semi-domesticated reindeer (Rangifer tarandus tarandus) was investigated through faecal pellet- group counts and by direct observations of reindeer from helicopter in the Langfjallet area in Idre reindeer herding district (62˚10’N) and in Mittadalen reindeer herding district (62˚50’N, aerial observations only). Reindeer pellets were found to be most abundant in habitats at high altitudes, and in some vegetation types. Pellet-group densities tended to be higher near the tourist trails, which often follow higher altitudes in the terrain. The aerial surveys showed that the reindeer moved towards higher altitudes when the wind speed was low and the temperature was high both in June and July. In June they moved towards lower regions when temperature was low and the wind speed was strong. The conclusion is that the reindeer use Langfjallet to escape insect harassment and warm weather, even though disturbance by tourism sometimes is high. Abstract in Swedish / Sammanfattning: Habitatval hos tamren (Rangifer tarandus tarandus) undersoktes genom att gora en spillningsinventering och genom att gora flygobservationer fran helikopter. Studien gjordes pa Langfjallet (62˚10’N) i Idre nya sameby och i Mittadalens samebys sommarbetesomrade (62˚50’N, endast flygobservationer). Pa Langfjallet finns det vandringsleder som ar frekventerade av vandrare fran juni manad fram till september. Spillningen visade att renarna foredrog hojderna i omradet samt en del av vegetationstyperna. Det var ocksa mer spillning narmare vandringslederna. Detta kan forklaras av att vandringslederna foljer hojderna i terrangen. Flyginventeringarna under bade juni och juli visade att renarna rorde sig mot hogre terrang nar det var varmt och lugnt vader. I juni rorde dom sig ocksa i lagre terrang nar det var stark vind och kallt vader. Slutsatsen ar att renarna valjer att vistas i hogre terrang for att undvika storningar fran insekter och for att finna svalka trots att det ar mansklig aktivitet i omradet.

Factors Influencing Lamb Survival in Four Swedish Sheep Breeds

Abstract 370000 litter records from the Swedish sheep recording scheme during 1974–80 were analysed according to the mortality rate for lambs at different ages from birth to 4––5 months of age. The four breeds included were Swedish Peltsheep (P), Swedish Finewool (Lf), Rya (Lr) and the Crossbred group (X), together comprising over 90% of all ewes in the national sheep recording scheme. The overall mortality rates were 6.13 in P, 12.71 in Lf, 9.78 in Lr and 8.14% in X. Corresponding figures for stillbirths were 1.74 (P), 5.20 (Lf), 3.73 (Lr) and 2.89 (X). Stillbirths and deaths during the first 4 days after birth constituted between one–half and three–fourths of all losses. Effects of year, region, flock size and birth season as well as interactions between these were significant, especially for stillbirths and deaths shortly after birth. Factors connected with season of birth seemed to be more important than factors associated with years, regions and flock size. Environmental factors of major importance i...

External signs of preparation for calving and course of parturition in Swedish dairy cattle breeds

Abstract The process of parturition, including the preparatory changes, was investigated in 159 animals during their first and subsequent calvings. Altogether 493 parturitions were studied in the following breed-groups of Swedish dairy cattle: Swedish Friesian (SLB), Swedish Red and White (SRB), first generation SRB × SLB crosses bred to either SRB or SLB sires, and Swedish Jersey (SJB). A wide variation between cows was found regarding both onset and progression of the external signs of impendent calving. The time for preparation of calving — swelling of the vulva and relaxation of the pelvic ligaments — increased significantly (0.001 ≤ P ≤ 0.05) with increasing parity, i.e. pluriparous cows showed signs of impendent calving earlier than primiparas. As regards enlargement of the udder, an inverse pattern was seen. The repeatabilities between parities for time intervals of signs of preparation were generally low (0.06-0.17). No difference was found between breeds regarding preparation for calving. An analysis of the value of various signs of impendent calving for predicting that calving would take place within 12 h after external inspection revealed that relaxation of the pelvic ligaments and udder distension were the most reliable and useful signs. For the events entrained during parturition (from the onset of restlessness until calving was completed) a significant effect of breed was found. The calving process proceeded faster for Jersey than for the other breeds. In the group of crossbred dams, the breed of the calfs sire affected the course of parturition. The process took longer for SLB-sired calves, being more similar to that of purebred SLB, whereas calving was quicker for the SRB-sired calves and was more similar to that of purebred SRB. The repeatabilities within dam for the later phases of the parturition process were higher (0.18-0.45) than for the preparatory signs. For stillborn calves the time interval from onset of labour until calving was completed was approximately twice as long as for liveborn calves. Rearing intensity, season of calving and sex of calf did not significantly affect any of the signs of preparation for calving or the signs during the process of parturition.

Optimal strategies for the use of reindeer rangelands

The problem of optimal adaptation of reindeer herds to rangelands under uncertain environmental conditions and measurement errors is studied by stochastic dynamic programming (SDP) and by stochastic optimisation in policy space (SOPS). The study expands on earlier studies by including measurement error, body weights, alternatives to lichen in winter pastures, wastage of lichen by cratering reindeer, and by including both summer and winter pastures in the same model. The analysis shows that it is important to get precise estimates of lichen growth, alternatives to lichen are only important if their digestibility is above a minimum level, variable costs only matter for the optimal herd size when summer grazing is limiting, modest discounting has little effect, the policy is not sensitive to the degree of natural variation, while the value of reindeer husbandry is significantly reduced by increasing climatic variation, the policy is sensitive to measurement error, and there is a considerable value of higher precision in measurements.

Non-destructive estimation of lichen biomass

Ground lichens constitute a vital part of reindeer winter diet, and non-destructive estimation of lichen biomass is therefore crucial for providing objective data for the management of lichen resources. The aim of this study is to compare precisions of different methods of estimating lichen biomass from ground cover and thallus heights of the four most important lichen species: Cladonia arbuscula, C. rangiferina, C. stellaris, and Cetraria islandica . The methods were validated against actual lichen biomass within 50 cm x 50 cm plots. Different methods gave remarkably similar results, except when cover estimation was based on presence/absence data with a strict criterion of 100% lichen cover. Average thallus heights within the plot explained the variation in lichen biomass as well as lichen volume (estimated from cover and average heights). Relationships between biomass and volume or height were also very similar for all four lichen species, and separation into species thus do not seem necessary for practical purposes. Abstract in Swedish / Sammandrag: Icke-destruktiv skattning av lavbiomassa Marklavar utgor en kritisk del av renars vinterfoda, och det blir darmed vasentligt att kunna skatta lavbiomassa pa ett icke-destruktivt satt for att kunna forvalta lavresursen. Syftet med denna studie ar att jamfora precisionen hos olika metoder for att skatta lavbiomassa baserat pa volym- och balhojdsmatningar for de fyra viktigaste arterna: Cladonia arbuscula, C. rangiferina, C. stellaris, and Cetraria islandica . Metoderna validerades mot lavbiomassa matt i 50 cm x 50 cm provytor. Olika metoder gav anmarkningsvart lika resultat, forutom nar tackning skattades med forekomstdata med ett strikt kriterium av 100% lavforekomst. Medelhojd pa lavbalarna i provytan forklarade lika mycket av variationen i lavbiomassa som lavvolym (baserat pa tackning och medelhojd). Forhallandet mellan biomassa och volym eller balhojd var ocksa mycket lika mellan arterna vilket medfor att det, for praktiska andamal, inte ar nodvandigt att separera arterna vid skattningar av total biomassa.

Progressing toward co-management through collaborative learning: forestry and reindeer husbandry in dialogue

With complex common pool resources, it is important to balance the multitude of interests in order to generate a sustainable management regime. This is not the case in the northern parts of Sweden, where forest resources are used for different extractive purposes by forest companies and the reindeer herding industry. In many respects, the present situation represents a classic collective-action problem with a number of reasons why no cooperative behaviour might be expected. This article illuminates the relationship between the two industries in an historical, ecological and institutional perspective in order to explain the limited scope of coordinated action between the two actors. It also, through the use of collaborative learning techniques and scenario methods, explores the possibilities for the two industries to consider each others needs and to identify strategies for co-existence and co-management. The testing of a broad range of scenarios among a selected group of stakeholders leads to the identification of possibilities for improving the management of the forest and lichen resource by changing institutional arrangements and improving coordination between the stakeholders.

Reindeer movement patterns in alpine summer ranges

To evaluate the movement rates of semi-domesticated reindeer (Rangifer tarandus tarandus) during the bare-ground season, we used successive GPS positions from 48 female reindeer. Data were collected during the summers of 2002 and 2003 in two Sámi reindeer herding districts in the Swedish mountains, Handölsdalen, and Sirges. The movement rates were analysed at five different time periods: over the whole season, and over the sub-seasons spring, and early summer, mid summer and early autumn. Variation in movements were analysed in relation to vegetation type, altitude, terrain ruggedness, temperature, wind speed, and proximity to hiking trails. We hypothesised that the foraging quality and different weather conditions is an important factor in determining movement rates. We found that reindeer movement rates were similar between study areas and were dependent on vegetation type and on weather conditions. Studying the circadian movements, in mid summer period when daytime oestrid activity are expected to be high, the reindeer stayed at higher altitudes where food quality was low, but moved to low altitudes at night where the food quality was higher. Therefore, we suggest that oestrid activity forces the reindeer to stay in low-quality vegetation types. Reindeer movements were linked to disturbance in areas of intermediate human activity. We found that in Handölsdalen, where hikers are abundant, the movement rates of reindeer decreased closer to the trails whereas in Sirges, where hikers are less abundant, the movement rates of reindeer increased closer to the trails.

Economic weight of tree survival relative to volume production in tree breeding: A case study with Pinus sylvestris in northern Sweden

Abstract The primary aim of the study was to estimate economic weights of survival relative to volume production per unit area, and to analyse the observable impact of changing survival, for five different breeding populations of Scots pine in northern Sweden. The economic weights were calculated from the model previously presented by the authors. Data from genetic field trials associated with the breeding populations were used both to estimate economic weights and to analyse the validity of the model. The breeding populations used were chosen to encompass a range of climatic conditions. The effects on the estimates of economic weights of increasing harshness (expressed as decreasing temperature sum), actual levels of both survival and patchiness of survival, and different initial stand densities were also analysed. The results showed that an appropriately parameterized model can be used to estimate economic weights for Scots pine in northern Sweden. Both the economic weight of survival and the observable impact of changing survival varied markedly between the studied breeding populations. Decreasing temperature sum had no trend with increasing economic weight of survival whereas decreasing survival and increasing patchiness of survival increased the estimated economic weight of survival more than three-fold.