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Within ungulate home ranges, suitable calving areas are of crucial importance for maintaining the reproductive potential of populations. Using GPS telemetry from a unique time series spanning before, during and after the construction of a 420-kV power line, we present results on calving site locations and area use during calving for two wild reindeer Rangifer tarandus tarandus populations (Setesdal West and Setesdal East) in Norway. For both populations, reindeer consistently preferred a core calving area at 4-8 km distance from the new power line in all three periods, indicating little preference of areas near the new power line. A reduction of the use of areas up to 6 km from the new power line during construction in Setesdal West may possibly indicate a disturbance effect. Contrary to our expectation, reindeer area use close to the new power line increased after construction in Setesdal East. Reindeer intensely used areas close to another existing 132 kV power line crossing the core calving area of Setesdal East during all years. However, reindeer area use was reduced up to 2 km from existing parallel 420 and 300 kV power lines located at the periphery of the calving area in Setesdal West, likely because of poor habitat. Our findings indicate that power lines may not be a disturbance causing avoidance effects for wild ungulates, while construction activities can induce a temporary reduction in area use. [ABSTRACT FROM AUTHOR]

Norwegian wild reindeer Rangifer tarandus tarandus are divided into 23 virtually isolated populations, primarily due to the abandonment of traditional migration and movement corridors caused by the development of infrastructures. By conducting a nation-wide, interdisciplinary pre-post study on a temporal scale spanning centuries, we modelled current reindeer movements with respect to archaeological findings to quantify long-term changes in area use related to anthropogenic disturbance. The location of 3,113 pitfall traps and hunting blinds, built 600-2000 years ago and used until 350-400 years ago, testified the location of traditional movement corridors. Current movement routes were delineated using Brownian Bridge Movement Models based on 147 reindeer GPS-monitored during 10 years. Using Path Analysis we quantified direct, indirect and total effects of different infrastructures within multiple scales (1, 5, and 10 km-radius buffers) on the current probability of use of ancient movement corridors. Tourist cabins and roads had the strongest long-term direct effects at most scales: 1 tourist cabin and 1 km road within a 1 km-radius buffer would lead, respectively, to complete area abandonment, and to a 46 % decrease in the probability of use. Power lines and private cabins had significant indirect effects on area use through their effect on roads, while hiking trails and, in particular, hydroelectric dams had highly variable effects, not significant at a nation-wide scale. Finally, we provide a flexible tool to estimate the potential long-term direct and cumulative effects of different types of infrastructures at the desired spatial scale to be used for the development of future sustainable land management plans. [ABSTRACT FROM AUTHOR]

Abstract: Linear infrastructures such as roads, pipelines and power lines can hinder Rangifer migration and reduce the total amount of area available for foraging. We studied the barrier and aversion effect of a 66kV power line transecting the range of wild reindeer in North Ottadalen, south central Norway using aerial surveys of reindeer distribution (direct measurement of reindeer use) and lichen measurements (indirect measurement of reindeer use) at varying distances from both sides of the power line. We present a clear definition of the expected barrier and aversion effects, and present specific hypotheses and predictions based on these two terms that are often used unclearly in the literature. The aerial surveys and ground observations showed that reindeer crossed underneath and grazed under and on both sides of the power line during 14 out of the 22years (63.6%) surveys were conducted over the last 31years. This behaviour was confirmed by the lichen measurements, indicating a higher use of lichen pastures along ridges close to and under the power line compared to those at increasing distances and up to 3km from both sides of the power line. This winter grazing pattern probably reflects the topographical channeling of reindeer to the ridges along an 8km wide topographical corridor encompassing the power line and cannot be attributed to the power line itself. We found that direct measurement data (visual observations such as ours or GPS/telemetry tracking) provide less ambiguous information for testing barrier and aversion effects than indirect measurement data (pasture/lichen measurements) that are likely influenced by numerous uncontrollable environmental variables independent of reindeer grazing. Our results contrast with recent studies indicating strong barrier and aversion effects of similar power lines for Rangifer migration and grazing behaviour in alpine terrain. [Copyright &y& Elsevier]