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Summary1. This study tested the relationships between both individual-level and predation-risk factors and the size of two home-range regions (HRR), defined as areas of different intensities of use. 2. We have expanded on previous home-range studies by testing the effects of two previously ignored individual-level factors: androgenization and energy reserves (body fat). 3. Location data were collected for wild individuals of Apodemus sylvaticus using the novel method of implanted PIT tags and mobile recording stations. A total of 68 home ranges were estimated using kernel density estimation. Home ranges were split into two regions (HRR): the 'core', representing the most intensively used areas, and 'periphery' regions. Body mass, body fat, sex, anogenital distance (AGD) (a proxy for androgenization) and the proportion of HRR, covered by antipredatory features (shrubs and fallen trees), were tested for their relationship with the size of core and periphery HRRs. Models were constructed for each HRR for three seasons: nonbreeding season (NBS), early and late breeding seasons (LBSs), to account for seasonal variation in behaviour associated with changes in food abundance and reproductive cycles. 4. Body fat had a negative relationship with periphery size and an interaction with sex on core size in the early breeding season (EBS). Body mass also had a significant interaction with sex on core size in the EBS. Androgenization has a strong effect on home range size in both sexes: AGD had a positive relationship with both HRRs for males in the LBS and females in the NBS. Males had larger peripheries than females in both early and LBSs. Habitat features that reduce predation risk explain HRR size throughout the breeding period. 5. This study emphasizes the importance of embracing natural complexity to gain insight into the drivers of space use behaviour; the consideration of individual and ecological factors, the recognition of the species-specific selective pressures that seasonal change presents for each sex and the identification of biologically meaningful home range areas will help advance the field.

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Game theoretical models have been developed to understand the decisions of individuals to continue or stop fighting. These can be split into self assessment models (cumulative assessment model (CAM), war of attrition without assessment (WOA-WA), energetic WOA), where contestants only have information on their own fighting persistence, and mutual assessment models (sequential assessment game: SAM), where contestants exchange information on each other's competitive ability. Here, we assess if self or mutual assessment occurs in fights between male mangrove treedwelling crabs, Selatium brockii (De Man, 1887). Contests were staged in the presence of a female between focal crabs belonging to either of two different absolute size classes against a smaller, size-matched, and larger opponent. In line with mutual assessment models and CAM, contest duration increased when contestants were more matched in competitive ability (i.e., size) but was not significantly different between focal crab sizes. However, this pattern differed between focal crab size classes when competitors were smaller, with contests lasting longer for the larger size class. Different behaviours with different levels of aggression were employed during contests, suggesting that mutual assessment occurs. However, unlike current model predictions, the different behaviours were not used in increasing order of aggressiveness. Instead, the sequence of behaviours used during a contest both increased and decreased in aggressiveness. These observations suggest that contests are a form of unbalanced partial assessment, corroborating other recent empirical findings, and challenging theoreticians to formalize such contest dynamics. RÉSUMÉDes modèles théoriques de jeu ont été développés pour comprendre les décisions des individus pour continuer ou arrêter de se battre. Ils peuvent être partagés en modèles d'auto-évaluation (modèle d'évaluation cumulative, CAM), guerre d'usure sans évaluation (WOA-WA), WOA énergique, où les adversaires ont seulement des informations sur leur propre persistance à se battre et modèles d'évaluation cumulatifs (jeux d'évaluation séquentielle: SAM), où les adversaires échangent des informations sur la capacité de compétition de chacun. Nous étudions ici l'évaluation auto et mutuelle qui intervient dans les combats entre crabes mâles arboricoles de la mangrove, Selatium brockii (De Man, 1887). Des combats ont été organisés en présence de femelles entre mâles appartenant soit à deux classes de taille différentes (plus petits ou plus grands) soit entre mâles de même taille.En accord avec les modèles d'évaluation mutuelle et CAM, la durée du combat augmente quand les combattants présentent une même capacité de compétition (i.e., taille), mais sans différence significative entre les tailles de crabe examinés. Cependant ce modèle diffère entre crabes expérimentés quand les concurrents sont plus petits, avec des combats plus longs pour la classe de plus grande taille. Différents comportements avec différents niveaux d'agression ont été employés ...