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Forest fragmentation may benefit generalist herbivores by increasing access to various substitutable food resources, with potential consequences for their population dynamics. We studied a European roe deer (Capreolus capreolus) population living in an agricultural mosaic of forest, woodlots, meadows and cultivated crops. We tested whether diet composition and quality varied spatially across the landscape using botanical analyses of rumen contents and chemical analyses of the plants consumed in relation to landscape metrics. In summer and non-mast winters, roe deer ate more cultivated seeds and less native forest browse with increasing availability of crops in the local landscape. This spatial variation resulted in contrasting diet quality, with more cell content and lower lignin and hemicellulose content (high quality) for individuals living in more open habitats. The pattern was less marked in the other seasons when diet composition, but not diet quality, was only weakly related to landscape structure. In mast autumns and winters, the consumption of acorns across the entire landscape resulted in a low level of differentiation in diet composition and quality. Our results reflect the ability of generalist species, such as roe deer, to adapt to the fragmentation of their forest habitat by exhibiting a plastic feeding behavior, enabling them to use supplementary resources available in the agricultural matrix. This flexibility confers nutritional advantages to individuals with access to cultivated fields when their native food resources are depleted or decline in quality (e.g. during non-mast years) and may explain local heterogeneities in individual phenotypic quality.

The use of fluctuating asymmetry (FA) for biomonitoring environmental stress is limited by the lack of work on how FA in particular traits responds to specific stresses. Here, by manipulating the number of individuals in an enclosed fallow deer (Dama dama) population, we describe, for the first time, clear density dependence in the FA of juvenile jaw morphology. The impact of high population density on FA was strong for both sexes, supporting the use of FA for indexing environmental stress. In addition, there was some indication that the change in FA was greater in males (43.6%) than females (28.5%). Finally, the ability to buffer density-dependent stress was independent of body condition. We suggest that, under highly limiting conditions, whole cohorts may be unable to buffer against developmental error, irrespective of individual quality.

In gregarious ruminants, females and males tend to live in separate groups outside the rutting season. According to the 'activity budget' hypothesis, this is due to an activity asynchrony between the two sexes reducing the lifetime of mixed-sex groups. We tested this hypothesis in a fallow deer population. Activity asynchrony was more frequent in mixed-sex than in single-sex groups. In addition, mixed-sex groups had a higher probability of splitting-up than all-female groups, and they mainly split up into single-sex groups. However, activity asynchrony did not appear as a major cause of splitting-up.

The article focuses on a study that investigated whether the capture and handling of roe deer Capreolus capreolus, a medium-sized ungulate, modified its space use, activity and habitat use immediately following release. It cites the effect of capture stress on mortality, biological or physiological parameters and reproduction. It mentions the approach used by the researchers to study the immediate, short-term effects of capture on the spatial behaviour of roe deer. It details the impact of landscape structure on the degree of post-capture homerange displacement.

Abstract: During the development of mammals, skeletal growth is an informative measure of homeostasis between environmental conditions and individual anabolism. Young animals are more sensitive to adverse conditions than adults because they invest the majority of their resources in somatic growth. Here, by means of a manipulative experience, we aim to explore the effect of density oscillations on skeletal development as measured by the age of ossification and the total length of the metacarpus in juvenile fallow deer (Dama dama Linneaus, 1758) inhabiting an enclosure (south-western France). Our results show that, for animals born at high density, the total length of the metacarpus was lower on average by about 11.2mm for females and 9mm for males compared to animals born in low-density conditions. Furthermore, we observed that the age of ossification of both sexes was earlier in animals that experienced high density during early growth (5.8 months for females and 7.7 months for males at high density versus 12 and 12.8 months, respectively at low density). The total length of metacarpi and the age of ossification did not differ between the sexes in both high- and low-density periods. We conclude that the length of bones and the age at which animals achieve total ossification is sensitive to changes in animal''s density, probably because of density-dependent competition for resources. [Copyright &y& Elsevier]