Dans cette thèse nous nous sommes intéressés au système Chevreuil-Homme pour comprendre comment les activités humaines peuvent impacter les patrons d’utilisation et de sélection des différents habitats. Une des manière dont les animaux peuvent résoudre ce compromis est par la modification de leurs patrons d’utilisation des habitats. Notamment dans le processus d’alimentation, les animaux doivent faire des compromis entre l’acquisition de ressources de bonnes qualités et l’évitement du risque de prédation ou de dérangement, car les meilleurs ressources sont généralement associées à un risque de prédation plus fort. Parce qu’il est quasiment impossible pour la plupart des organismes desatisfaire l’ensemble de leurs activités fondamentales (alimentation, reproduction, repos,…) sans encourir un risque de prédation, ils sont souvent confrontés à des compromis. Les populations sauvages sont de plus en plus soumises à d’importantes pressions de prédation en lien avec les activités humaines, qui sont la source de multiples facteurs de stress pour les populations sauvages. KeywordsMovement rates-Temperature-Wind speed-GPS collars-Ungulates-Insect harassment-Human disturbance 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. Reindeer movements were linked to disturbance in areas of intermediate Therefore, we suggest that oestrid activityįorces the reindeer to stay in low-quality vegetation types. Was low, but moved to low altitudes at night where the food quality was higher. 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 On vegetation type and on weather conditions. We found that reindeer movement rates were similar between study areas and were dependent We hypothesised that the foraging quality and different weather conditions is an importantįactor in determining movement rates. Variation in movements were analysed in relation to vegetation type, altitude, terrain ruggedness, temperature, wind speed,Īnd proximity to hiking trails. 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. Summers of 20 in two Sámi reindeer herding districts in the Swedish mountains, Handölsdalen, and Sirges. 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.
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