Capreolus capreolus

An fluorotischen und nicht fluorotischen Zähnen des Rehes wurden Fluorgehalt und Fluorverteilung in Schmelz und Dentin bestimmt. Die hohen Fluorkonzentrationen im Oberflächenschmelz der in fluorotischen Gebissen regelmäßig geschädigten P4 werden auf posteruptive Fluorideinlagerung in die untermineralisierten (porösen) Schmelzschichten zurückgeführt. Die Tatsache, daß bei diesen P4, im Vergleich mit den nicht oder nur sehr leicht geschädigten M1 aus den gleichen Backenzahnreihen, auch in den inneren Schmelz- sowie den schmelznahen Dentinzonen erhöhte Fluorgehalte gemessen wurden, weist darauf hin, daß während der Kronenbildung der P4 deutlich höhere Plasma-Fluoridgehalte gegeben waren als im Fall der Mineralisation der Zahnkronen der M1. Die Befunde bestätigen somit die bereits früher geäußerte Hypothese (Kierdorf 1988), daß die während der Fetal- und frühen Postnatalphase mineralisierenden Zähne des Rehes aufgrund des Wirkens verschiedener Faktoren, auch in einer durch Fluorverbindungen stark kontaminierten Umwelt, bis zu einem gewissen Grade vor einer Schädigung durch Fluoride geschützt sind. Fluorine content and distribution in enamel and dentine were studied in fluorosed and unfluorosed mandibular cheek teeth. The high fluorine concentration found in surface enamel of P4, which in fluorotic animals regularly exhibited pathological alterations, is attributed to posteruptive fluoride accumulation by this hypomineralized enamel layer. The fact that in these teeth, when compared with the not or only very slightly fluorosed M1 taken from the same mandibles, higher fluorine concentrations were also detected in subsurface enamel and dentine near the dentinoenamel junction is seen as indicative that plasma-fluoride values during mineralization of the fourth premolars' tooth crowns were significantly higher than in the case of first molars. Thus, the results of our study corroborate the hypothesis (Kierdorf 1988) that the teeth of roe deer mineralizing during fetal and early postnatal life, due to the action of different mechanisms, are to some extend protected from fluoride damage even in an environment heavily contaminated by fluoride compounds. La teneur en Fluor et sa répartition dans l'émail et dans la dentine de dents fluorées et non-fluorées de chevreuils ont été déterminées. Les hautes concentrations à la surface de l'émail de P4 de maxillaires fluorés, régulièrement endommagés, ont été attribuées à des accumulations post-éruptives de Fluor dans les couches poreuses d'émail sousminéralisées. Le fait que, chez ces P4, par comparaison avec les M1 trés peu ou pas endommagées de la même rangée dentaire, des teneurs élevées de Fluor ont également été mesurées dans les couches internes d'émail ainsi que dans les zones de dentine adjacentes, indique que, pendant la formation des couronnes de la P4, il se trouvait des teneurs en fluorides plasmatiques nettement plus élevées que dans le cas de la minéralisation de la couronne dentaire de la M1. Ces constatations confirment ainsi l'hypothèse, déjà formulée antérieurement (Kierdorf 1988), suivant laquelle, pendant les stades foetal et post-natal, les dents en voie de minéralisation du Chevreuil, sont, sous l'effet de divers facteurs, protégées jusqu'à un certain degré d'une dégradation par les fluorides, même dans un environnement fortement contaminé par des composants fluorés.

The year-round food habits of lynx were studied using radio-telemetry and snow-tracking in the boreal forest of southeastern Norway. The main objectives of the study were to clarify the importance of domestic sheep and small prey species in the diet of lynx in an area with a very low density of roe deer. During the period 1995–1999, we found 193 scats and 358 kills made by lynx. Our results indicate that roe deer were the most common prey species (contributing to 83 and 34% of the biomass consumed in winter and summer, respectively), although a wide range of other species were also found, including mountain hares, tetranoids, red foxes, domestic sheep, wild reindeer, and even moose. Most of the diet was obtained by predation, although we did document several cases of scavenging. Roe deer were more important in the diet in winter than in summer, perhaps because they were easier to locate in winter as they clustered around feeding sites. In summer, domestic sheep and small prey increased in importance. Despite the very low density of roe deer in this study area, lynx seemed to still specialise on them, although domestic sheep did constitute a significant amount to their diet, especially for males and yearlings. However, the contribution of sheep to summer diet was far from that expected if their relative density was considered.

... layers (herbaceous layers <0.5 m, low shrubs between 0.5 and 2 m, high shrubs between 2 and 8 m and trees >8 m). For each plot and layer, we recorded the abundance-dominance of all vascular plant species with a scale of 7 levels (Braun-Blanquet, 1932): absence, rare and ...

Late Pleistocene extinctions are of interest to paleontological and anthropological research. In North America and Australia, human occupation occurred during a short period of time and overexploitation may have led to the extinction of mammalian megafauna. In northern Eurasia megafaunal extinctions are believed to have occurred over a relatively longer period of time, perhaps as a result of changing environmental conditions, but the picture is much less clear. To consider megafaunal extinction in Eurasia, we compare differences in the geographical distribution and commonness of extinct and extant species between paleontological and archaeological localities from the late middle Pleistocene to Holocene. Purely paleontological localities, as well as most extinct species, were distributed north of archaeological sites and of the extant species, suggesting that apart from possible differences in adaptations between humans and other species, humans could also have a detrimental effect on large mammal distribution. However, evidence for human overexploitation applies only to the extinct steppe bison Bison priscus. Other human-preferred species survive into the Holocene, including Rangifer tarandus, Equus ferus, Capreolus capreolus, Cervus elaphus, Equus hemionus, Saiga tatarica, and Sus scrofa. Mammuthus primigenius and Megaloceros giganteus were rare in archaeological sites. Carnivores appear little influenced by human presence, although they become rarer in Holocene archaeological sites. Overall, the data are consistent with the conclusion that humans acted as efficient hunters selecting for the most abundant species. Our study supports the idea that the late Pleistocene extinctions were environmentally driven by climatic changes that triggered habitat fragmentation, species range reduction, and population decrease, after which human interference either by direct hunting or via indirect activities probably became critical.

Although drive counts are frequently used to estimate the size of deer populations in forests, little is known about how counting methods or the density and social organization of the deer species concerned influence the accuracy of the estimates obtained, and hence their suitability for informing management decisions. As these issues cannot readily be examined for real populations, we conducted a series of ‘virtual experiments’ in a computer simulation model to evaluate the effects of block size, proportion of forest counted, deer density, social aggregation and spatial auto-correlation on the accuracy of drive counts. Simulated populations of red and roe deer were generated on the basis of drive count data obtained from Polish commercial forests. For both deer species, count accuracy increased with increasing density, and decreased as the degree of aggregation, either demographic or spatial, within the population increased. However, the effect of density on accuracy was substantially greater than the effect of aggregation. Although improvements in accuracy could be made by reducing the size of counting blocks for low-density, aggregated populations, these were limited. Increasing the proportion of the forest counted led to greater improvements in accuracy, but the gains were limited compared with the increase in effort required. If it is necessary to estimate the deer population with a high degree of accuracy (e.g. within 10% of the true value), drive counts are likely to be inadequate whatever the deer density. However, if a lower level of accuracy (within 20% or more) is acceptable, our study suggests that at higher deer densities (more than ca. five to seven deer/100 ha) drive counts can provide reliable information on population size.

In recent decades, Mediterranean landscapes have been experiencing more rapid changes in land use than usual, which have affected the ecology of the species inhabiting this biodiversity hotspot. Some studies have assessed the effect of such changes on biodiversity, but most of these were diachronic studies of population dynamics, or synchronic studies of species habitat selection, whereas few studies have simultaneously taken into account temporal changes in habitat composition and changes in species distribution. This study analysed the effects of land-use changes on the distribution of wild ungulates (Capreolus capreolus, Capra pyrenaica, Cervus elaphus and Sus scrofa). Using favourability function and Markov chain analysis combined with cellular automata, we addressed the following objectives: (i) to examine the environmental determinants of ungulate distribution in the past (1960s) and present (1990s), (ii) to model land use for 2040 to forecast future species distributions and (iii) to assess the biogeographical differences between the above-mentioned study periods (past–present and present–future). Species favourability was predicted to be more widely distributed in the present than in the past, but this increase varied across species. Areas predicted to be favourable in the present should remain stable in the future, but in addition there will be more new favourable areas not previously occupied by these species. The results are discussed from the perspective of the socio-economic relevance of wild ungulates in relation to some unfavourable areas of Mediterranean regions.

Studies on predation by the wolf (Canis lupus) have often reported contradictory results about the role of prey density and vulnerability on wolf prey use. We investigated dietary response and prey selection by wolves in a high-density and multi-species ungulate community, analysing scats collected over a period of 11 years in the Casentinesi Forests, Italy. The second most abundant species, wild boar (Sus scrofa), was found to be the main wolf prey, and we did not observe any dietary response of wolves to variations in the density of either primary or secondary prey species. Selection patterns were uniform throughout the study period. Wolves strongly selected for wild boar piglets, while roe deer (Capreolus capreolus) fawns and adults, red deer (Cervus elaphus) adults and fallow deer (Dama dama) adults were avoided. Wolf preference for wild boar was inversely density dependent. Within each species, juveniles were preferred to adults. Medium-sized, young individuals of both wild boar and roe deer were optimal prey, although with different selection patterns related to the different anti-predator strategies adopted by each prey species. The results of this study suggest that in productive ecosystems with high density and high renewal rates of prey, selection patterns by wolves are determined by prey vulnerability, which is connected to prey age and body size. The different patterns of wild boar versus cervids use by wolf across Europe seems to be related to their relative abundances, while the strong selection of wild boar in Italian Apennines with respect to the more frequent avoidance in central-eastern Europe is better explained by higher piglet productivity and smaller body size of adults boar in Mediterranean temperate forests.