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The social, spatial, and genetic structures of populations depend on where offspring settle and reproduce in relation to their parent’s home range. However, the patterns of settlement in wild populations of large mammals are often poorly described owing to the difficulty of monitoring mother-offspring pairs over a long period. Here, we investigated sex-specific settlement patterns in chamois (Rupicapra rupicapra (L., 1758)) based on the study of 31 mother-offspring pairs. We calculated the distance between the center of the mother’s range and the center of her offspring’s range, and tested whether this distance differed when the offspring was immature (i.e., a yearling) and after offspring sexual maturity (>2 years of age). We found no sex effect on the distance between centers of mother and offspring ranges for yearling offsprings. However, mature sons ranged farther away from their mother than mature daughters. Daughters appear to settle close to their mother’s home range. The distance at which a daughter settles compared with her mother’s range seems to be determined before 2 years of age. On the contrary, the distance between the center of the locations of yearling males and the center of locations of their mother does not predict how far away males will eventually settle when mature. We discuss the implications of these patterns for generating female social structures, as well as population spatial and genetic structures. Les structures sociales, spatiales et génétiques des populations dépendent du lieu où les rejetons vont s’installer et se reproduire par rapport au domaine vital de leur parents. Cependant, les patrons d’installation dans les populations sauvages de grands mammifères sont souvent peu décrits car il est difficile de suivre les couples mères-jeunes sur une période longue. Ici, nous avons étudié les patrons d’installation chez le chamois (Rupicapra rupicapra (L., 1758)) en fonction de leur sexe chez 31 couples mères-jeunes. Nous avons calculé la distance entre le centre du domaine vital de la mère et le centre de celui de son jeune et testé si la distance différait quand le jeune était immature (jeune de 1 an) et avait atteint la maturité sexuelle (>2 ans). Nous n’avons pas trouvé d’effet du sexe sur la distance entre les centres des domaines de la mère et du jeune pour les jeunes immatures. Cependant, les fils adultes sont partis s’installer plus loin de leur mère que les filles adultes. La distance à laquelle une fille s’installe par rapport au domaine vital de sa mère semble déterminée avant l’âge de 2 ans. Au contraire, la distance entre les centres des localisations des mâles de 1 an et le centre des localisations de la mère ne permet pas de prédire la distance d’installation du fils lorsqu’il est adulte. Nous discutons de l’implication de ces patrons dans l’émergence des structures sociales femelles et des structures spatiale et génétique des populations. [ABSTRACT FROM AUTHOR]

The Mahalanobis distances have been introduced in habitat selection studies for the estimation of environmental suitability maps (ESMs). The pixels of raster maps of a given area correspond to points in the multidimensional space defined by the mapped environmental variables (ecological space). The Mahalanobis distances measure the distances in this space between these points and the mean of the ecological niche (i.e., the hypothesized optimum for the species) regarding the structure of the niche. The map of these distances over the area of interest is an estimated ESM. Several authors recently noted that the use of a single optimum for the niche of a species may lead to biased predictions of animal occurrence. They proposed to use instead a minimum set of basic habitat requirements, found by partitioning the Mahalanobis distances into a restricted set of biologically meaningful axes. However, the statistical approach they proposed does not take into account the environmental conditions on the area where the niche was sampled (i.e., the environmental availability), and we show that including this availability is necessary. We used their approach as a basis to develop a new exploratory tool, the Mahalanobis distance factor analysis (MADIFA), which performs an additive partitioning of the Mahalanobis distances taking into account this availability. The basic habitat requirements of a species can be derived from the axes of the MADIFA. This method can also be used to compute ESMs using only this small number of basic requirements, therefore including only the biologically relevant information. We also prove that the MADIFA is complementary to the commonly used ecological-niche factor analysis (ENFA). We used the MADIFA method to analyze the niche of the chamois Rupicapra rupicapra in a mountainous area. This method adds to the existing set of tools for the description of the niche. [ABSTRACT FROM AUTHOR]

Although it is widely accepted that populations vary in space and time, defining the spatial scale of population structure relevant for understanding temporal variation or for management and conservation purposes remains a challenge. We studied jointly temporal patterns of social and spatial structures in an introduced population of mouflon (Ovis gmelini musimon (Schreber, 1782)) to define the temporal stability of these structures and to uncover the history of the colonization process. We expected social organization to remain stable between years, mouflon to stay sedentary, and colonization to have occurred through a diffusion process. We used yearly censuses performed between 1994 and 2004, and collected information in managers’ archives and newspapers reporting the presence of mouflon in different areas since its introduction in 1954 in the Bauges mountains, France. Mouflons were divided into male and nursery groups, whose number (1.88 ± 0.31 for males and 7.54 ± 0.58 for nurseries) and composition (7.05 ± 1.25 individuals in male groups; 13.6 ± 1.41 females, 8.11 ± 0.72 lambs, and 6.51 ± 0.65 males in the nurseries) remained stable over years. The spatial distribution of nursery groups was clustered in five areas, highly correlated between years (p < 0.001), suggesting that the same groups were observed in given areas every year and confirming the sedentary lifestyle of the species. The presence–absence data of the species since its introduction suggested a colonization by diffusion. We discuss the social and spatial structures of the population and the type of colonization process that could have led to this kind of structure. [ABSTRACT FROM AUTHOR]

• The spatio-temporal distribution of floating litter was predicted at the Mediterranean level with a model coupled with a literature review. • The main litter accumulation patterns are located in the western and central sub-basins. • Litter in the Levantine sub-basin strand locally without outflow to other sub-regions. • Macro and micro-litter spatial accumulation patterns are not correlated. The Mediterranean Sea is now acknowledged to be a hot spot for marine litter. However, little is known about Floating Macro Litter (FML) concentration at the scale of the entire basin; predictions regarding this would greatly help guide policymaking to fight this scourge. While previous studies have shown high spatio-temporal variability in FML distribution, the aim of this study was to accurately identify seasonal debris accumulation patterns on regional and local spatial scales across the Mediterranean basin. The objective was then to quantitatively compare this distribution model to other simulations and empirical data. We first studied FML distribution with a 2-D Lagrangian model coupled to an oceanic general circulation model (OGCM) at a horizontal resolution of 1/ 12 °. From an initial homogeneous deployment, we deployed a set of > 10 8 virtual particles across the whole basin and tracked each particle during 3-month journeys. Then we described the FML distribution model outputs and compared them both to empirical observations at the scale of the whole basin (gathered from a review of scientific papers on surface debris distribution), and to other numerical FML simulations from previous studies. The results of our offshore modeled distribution of FML fully agreed with characteristic debris accumulation patterns analyzed in our review of other studies. This indicates that our model could allow the prediction of monthly litter accumulation patterns at the scale of the entire Mediterranean Sea. [ABSTRACT FROM AUTHOR]