Production de bois et autres ressources (gibier, champignons,...), conservation de la biodiversité et gestion des paysages, la forêt a suscité de riches débats depuis quelques années, le Grenelle de l'Environnement ayant révélé des intérêts parfois contradictoires. Si le gestionnaire forestier tente de développer autant que possible une gestion multifonctionnelle de ses forêts, il reste dépendant des connaissances fragmentaires sur les interactions dans les écosystèmes forestiers. La politique actuelle, qui vise à concilier la production de bois et la préservation des espèces, repose plus sur des expériences de terrain que sur des études étayées scientifiquement. Les Chiroptères comptent des espèces candidates pour étudier l'influence de la gestion forestière sur la biodiversité : le jour, elles occupent des gîtes arboricoles et, la nuit, elles exploitent des habitats forestiers pour chasser leurs proies, qui dépendent elles-mêmes de micro-habitats forestiers. Pour aider le gestionnaire à mettre en œuvre une stratégie de gestion conservatoire, nous avons étudié l'utilisation des ressources de la forêt par trois espèces : Myotis bechsteinii, Myotis nattereri et Plecotus auritus. La radio-localisation a permis d'identifier des réseaux d'arbres-gîte dont l'occupation varie selon les espèces, leur statut reproducteur et l'implication dans le comportement de fission-fusion des colonies de parturition. Les différentes utilisations des gîtes impliquent une stratégie de gestion propre à chaque espèce, voire à chaque colonie de reproduction. Procurant a priori de potentiels gîtes et proies, le bois mort debout favorise la richesse spécifique des Chiroptères forestiers à partir de 25 m3 à l'hectare, mais une stratification de la végétation pourrait être un objectif de gestion, la réponse des espèces était essentiellement liée à la structure forestière des trouées induites par le bois mort. Ce travail a ensuite nécessité de s'intéresser aux méthodes permettant de comprendre l'utilisation de l'espace par chaque individu (domaine vital) et la façon dont chacun d'eux fréquente ses terrains de chasse (sélection de l'habitat). Compte tenu des limites technologiques, le Kernel semble actuellement la meilleure méthode de représentation et de calcul de surface du domaine vital alors que la K-select a livré des résultats significatifs pour mettre en évidence des facteurs de sélection d'habitat. Les surfaces des domaines vitaux et des centres d'activité varient selon les espèces, Myotis bechsteinii associe de petites surfaces à un comportement territorial, surtout en période d'allaitement. M. nattereri et Plecotus auritus peuvent exploiter de grands espaces sur lesquels ils se limitent à de petits centres d'activité. Les colonies de ces dernières pourront plus facilement se déplacer dans leur domaine vital au gré des itinéraires de gestion mis en œuvre. Les caractéristiques des habitats forestiers utilisés comme terrains de chasse varient selon les espèces, voire le sexe, l'âge et le statut reproducteur des individus, mais toutes trois montrent une forte sélectivité pour les peuplements forestiers présentant un fort encombrement végétal, des gros arbres et une forte structuration du peuplement. Cinq principes de gestion dans un contexte fort de production de bois sont développés en conclusion des résultats avec deux exemples de stratégies de gestion destinée au maintien des Chiroptères. / The forest is the center of many interests that fuel the debates of our society. These debates are particularly exacerbated since the french " Grenelle de l'Environnement " in 2008. Among the various expectations, forest produce wood that is the subject of attentions, both by an increased demand for certain types of trees and by the naturalist world which sees in it one of last refuges for biodiversity in our modified landscapes. Thus, if the forest manager is trying to develop a management that is as much multifunctional as possible, it remains dependent on fragmented knowledge on the link between biodiversity and the forest ecosystem. Despite the establishment of a conservation policy that seeks to balance timber production and species preservation, the way to conduct such a policy is based on concrete field experiences yet scientifically unsubstantiated. Bats are good candidate species to study the response of biodiversity to forest management: they select networks of tree-roosts in which they form breeding colonies composed of several dozen individuals and they exploit forest habitats to hunt their prey, prey which themselves depend on forest microhabitats. However, their study is recent in forest and provides very vague management guidelines. To help managers implement a conservation management strategy, we thus studied the behavior of forest usage by three species of gleaning bats, Myotis bechsteinii, Myotis nattereri and Plecotus auritus. This work required to focus on the methods available to understand the use of space by each individual (home range) and how each individual selects its hunting habitats. We showed that each species had a unique response to available habitats and that the status of individuals (sex, age and reproductive status) intervenes in explaining the selection of tree roosts and hunting grounds. Both compartments are constrained by the availability of suitable habitat, helping to explain the structuring of habitat selection factors and the shape and surface of individual home ranges. Furthermore, the way networks of tree-roost are used partly explains the types of roosts selected. These different results means that it is necessary to lay down specific management strategies for each species, even each breeding colony. Finally, we studied the role of deadwood to explain the presence of bats in forests. We have shown that species richness increased from standing deadwood of 25m3 per hectare, while the response of species to deadwood was mainly restricted to forest habitat structure produced by the gaps resulting from the deadwood patch, favoring particularly edge-foraging species. Some species do however clearly benefit from insects emerging from deadwood. Five recommendations are proposed for the conservation of these species in a context of strong wood production.

The main aim of this study was to classify and describe the plant communities in the home range of white rhinoceros in order to understand the animal seasonal foraging ecology. To provide a detailed habitat description, forty sample plots were stratified randomly. A TWINSPAN classification, refined by Braun-Blanquet procedures, was carried out on the Viewpoint section of the reserve. Ten plant communities, grouped into five major community types, were identified. The veld condition and ecological carrying capacity in these communities were measured, stating an abundance of food on long grass while the short grass equal the number of short grass feeders. A number of behavioural aspects such as activity data, home range utilization and dietary usage were examined. Statistical methods such as the Spearman rank-order correlation, Wilcoxon sign test and Student T-test were used on rhino data. The difference in usage of the home range during wet and dry seasons was insignificant. / Environmental Sciences / M.Sc. (Environmental Management)

Abstract Between October 1999 and October 2003, 30 adult and 48 young (< 1 year) raccoon dogs (Nyctereutes procyonoides) were monitored using radio-telemetry in an area of Germany which has been occupied by this invasive alien species since the early 1990s. Additionally, three pairs of raccoon dogs were observed by continuous radio-tracking during the first six weeks after parturition in 2003. Furthermore 136 raccoon dog pubs were ear-tagged between June 1999 and August 2006. No adult animals dispersed from the area during the study period and home ranges tended to be used for several years, probably for life. The average annual home range size, calculated using 95% fixed kernel, was 382.2 ha ± 297.4 SD for females (n = 30 seasonal home ranges) and 352.4 ha ± 313.3 SD for males (n = 32 seasonal home ranges). Paired raccoon dogs had home ranges of similar size, with pair sharing the same area all year round. Raccoon dogs occupied large core areas (85% kernel) covering 81.2% of their home ranges. The home ranges were at their smallest during the mating season. The slightly larger size of home ranges in winter suggests that, due to the temperate climate, raccoon dogs do not hibernate in Germany. Males and females formed a long-term (probably lifelong) pair bond. Same-sex neighbours ignored each other and even adjacent males/females showed neither preference nor avoidance. Thus, it can be assumed that the raccoon dog in Central Europe is monogamous without exclusive territories, based on the results of home range overlap analysis and interaction estimations. Habitat composition within home ranges and within the whole study area was almost equal. Although, percentage shares of farmland and meadow was 16.35% smaller and 12.06% higher within the home ranges, respectively. All nine habitat types (farmland, forest, settlement, water, meadows, maize fields, small woods, reeds and hedges) were used opportunistically by raccoon dogs. No significant, recognisable difference for habitat preferences between seasons was detected. Male and female raccoon dog showed equal habitat preference pattern. A comparison of active and inactive locations in different habitats found no remarkable differences. Habitat composition of individual home ranges was used to classify animals. If the percentage of forest within a home range exceeded 50% the individual was classified as a ‘forest type’ raccoon dog. If the percentage of forest habitats within a home range was less than 5%, the share of pastureland was mean 81.82% ± 16.92 SD. Consequently the individual was classified as a ‘agrarian type’ raccoon dog. Neither habitat preference nor habitat selection process differed between the two ‘types’. Habitat use and preference is discussed with relation to the ability of the raccoon dog to expand its range towards Western Europe. Males spent noticeably more time (40.5% of the time ±11.7 SD) alone with the pups than females (16.4% of the time ±8.5 SD). Females had noticeably larger 95% kernel home ranges (98.24 ha ±51.71 SD) than males (14.73 ha ±8.16 SD) and moved much longer daily distances (7,368 m ±2,015 SD) than males (4,094 m ±2,886 SD) in six weeks postpartum. The raccoon dogs being studied left the breeding den in the 6th week after the birth of the pups. In situ video observation showed that the male carried prey to the den to provide the female and the litter with food. A clear division of labour took place among parents during the period in which the pups were nursed: males guarded the litter in the den or in close vicinity of it, while the females foraged to satisfy their increased energy requirements. There were relocations of 59 (43.4%) ear-tagged young racoon dogs and mean distance from marking point was 13.5 km ±20.1 SD. Dispersal mortality rate was 69.5% among young raccoon dogs. Most animals (55.9%) were recovered nearer than 5 km from the marking point, whereas only 8.5% relocations were recorded further than 50 km from the marking point. There was no difference in the distances of relocations between sexes. Most (53.7%) relocations of ear-tagged young raccoon dogs were in August and September and, only 34.1% were recorded from October to April. Hunting (55 %) and traffic (27 %) were the major mortality factors. Radio-collared young raccoon dogs generally dispersed between July and September. The mean natal home range size (MCP 100%) with and without excursions was 502.6 ha ±66.4 SD (n = 9) and 92.1 ha ±66.4 SD (n = 17), respectively. There were no differences between sexes in the month of dispersal. The direction of travel for dispersing animals appeared to be random, with distances from 0.5 km to 91.2 km. A highly flexible dispersing behaviour is certainly one of the reasons which contribute to the high expansion success of the species.

Between October 1999 and October 2003, 30 adult and 48 young (< 1 year) raccoon dogs (Nyctereutes procyonoides) were monitored using radio-telemetry in an area of North-East Germany which has been occupied by this invasive alien species since the early 1990s. Additionally, three pairs of raccoon dogs were observed by continuous radio-tracking during the first six weeks after parturition in 2003. Furthermore 136 raccoon dog pubs were ear-tagged between June 1999 and August 2006. No adult animals dispersed from the area during the study period and home ranges tended to be used for several years, probably for life. The average annual home range size, calculated using 95% fixed kernel, was 382.2 ha ± 297.4 SD for females (n = 30 seasonal home ranges) and 352.4 ha ± 313.3 SD for males (n = 32 seasonal home ranges). Paired raccoon dogs had home ranges of similar size, with pair mates sharing the same area all year round. Raccoon dogs occupied large core areas (85% kernel) covering 81.2% of their home ranges. The home ranges were at their smallest during the mating season. The slightly larger size of home ranges in winter suggests that, due to the temperate climate, raccoon dogs do not hibernate in Germany. Males and females formed a long-term (probably lifelong) pair bond. Same-sex neighbours ignored each other and even adjacent males/females showed neither preference nor avoidance. Thus, it can be assumed that the raccoon dog in Central Europe is monogamous without exclusive territories, based on the results of home range overlap analysis and interaction estimations. Habitat composition within home ranges and within the whole study area was almost equal. Although, percentage shares of farmland and meadow was 16.35% smaller and 12.06% higher within the home ranges, respectively. All nine habitat types (farmland, forest, settlement, water, meadows, maize fields, small woods, reeds and hedges) were used opportunistically by raccoon dogs. No significant, recognisable difference for habitat preferences between seasons was detected. Male and female raccoon dog showed equal habitat preference pattern. A comparison of active and inactive locations in different habitats found no remarkable differences. Habitat composition of individual home ranges was used to classify animals. If the percentage of forest within a home range exceeded 50% the individual was classified as a ‘forest type’ raccoon dog. If the percentage of forest habitats within a home range was less than 5%, the share of pastureland was mean 81.82% ± 16.92 SD. Consequently the individual was classified as a ‘agrarian type’ raccoon dog. Neither habitat preference nor habitat selection process differed between the two ‘types’. Habitat use and preference is discussed with relation to the ability of the raccoon dog to expand its range towards Western Europe. Males spent noticeably more time (40.5% of the time ±11.7 SD) alone with the pups than females (16.4% of the time ±8.5 SD). Females had noticeably larger 95% kernel home ranges (98.24 ha ±51.71 SD) than males (14.73 ha ±8.16 SD) and moved much longer daily distances (7,368 m ±2,015 SD) than males (4,094 m ±2,886 SD) in six weeks postpartum. The raccoon dogs being studied left the breeding den in the 6th week after the birth of the pups. In situ video observation showed that the male carried prey to the den to provide the female and the litter with food. A clear division of labour took place among parents during the period in which the pups were nursed: males guarded the litter in the den or in close vicinity of it, while the females foraged to satisfy their increased energy requirements. There were relocations of 59 (43.4%) ear-tagged young raccoon dogs and mean distance from marking point was 13.5 km ±20.1 SD. Dispersal mortality rate was 69.5% among young raccoon dogs. Most animals (55.9%) were recovered nearer than 5 km from the marking point, whereas only 8.5% relocations were recorded further than 50 km from the marking point. There was no difference in the distances of relocations between sexes. Most (53.7%) relocations of ear-tagged young raccoon dogs were in August and September and, only 34.1% were recorded from October to April. Hunting (55 %) and traffic (27 %) were the major mortality factors. Radiocollared young raccoon dogs generally dispersed between July and September. The mean natal home range size (MCP 100%) with and without excursions was 502.6 ha ±66.4 SD (n = 9) and 92.1 ha ±66.4 SD (n = 17), respectively. There were no differences between sexes in the month of dispersal. The direction of travel for dispersing animals appeared to be random, with distances from 0.5 km to 91.2 km. A highly flexible dispersing behaviour is certainly one of the reasons which contribute to the high expansion success of the species.

No description available.