Mating strategies of Pampean mouse males

Abstract

Patterns of space use and sexual dimorphism are frequently used to infer mating systems. We examined body size and home range size and intra-and intersexual overlap degree in order to elucidate mating strategy of Akodon azarae males. We studied spacing patterns using 113 and 129 home ranges established by males and females, respectively, in four 0.25 ha enclosures during the breeding season. Significant differences between sexes in home range size and overlap degree were found. Male home ranges were always larger than those of females. We observed exclusive space use among males and among females. Considering only those males that shared their home ranges with females, average intersexual overlap value was about 50%. Males mainly overlap their home ranges with home ranges of two or three females. Significant differences in body size were found between males and females, with males being larger. We concluded that space use and sexual dimorphism in this species is consistent with patterns characteristic of polygynous rodents, and we propose a polygynous system in A. azarae.

Female Intrasexual Territoriality and its Potential Adaptive Significance: The Pampean Grassland Mouse as an Ecological Model Species

“…Taken together, current evidence is more consistent with the hypothesis that A. azarae breeding females are aggressive against intruder females as a strategy to protect their offspring, a possibility that could explain interfemale spatial avoidance recorded both in wild and in enclosed populations of this species (Priotto & Steinmann ; Bonatto et al. , ; Ávila et al. ).…”

“…Contrarily, in the polygynous species A. azarae , females that maintained exclusive home ranges respect to other females both in wild and enclosed populations did not show any injury evidences even when population densities reached the highest values (Priotto & Steinmann ; Bonatto et al. ; Ávila et al. ).…”

“…Akodon azarae has a polygynous mating system that operates through female defence, in which a minority of males (40%) monopolize several fertile females leaving other males without access to them (Bonatto et al. , 2013a). In this species, during the breeding period, male home range sizes are always larger than females (240 and 160 m 2 , respectively), show longer movement distances than females (63.5 and 25.6 m, respectively) and female intrasexual overlap percentages are always lower than those of males (7% female/female and 12% male/male) (Priotto & Steinmann ; Gomez et al.…”

“…Thus, territoriality of breeding females in A. azarae initially was assumed based on the little overlapping degree recorded between female home ranges (Priotto & Steinmann ; Bonatto et al. ). Considering that A. azarae females are more sensitive than males to ecological resources (Bonaventura et al.…”

Spacing Behavior of a Non‐Larder‐Hoarding Tamiasciurus: A Study of Mearns's Squirrels in Xeric Coniferous Forests

“…; Bergallo & Magnusson ; Shier & Randall ; Edelman & Koprowski ; Cudworth & Koprowski ; Adler ; Bonatto et al. ). In other words, whereas seasonal variation in home‐range size of red and Douglas's squirrels is influenced by sexual activity and food supply due to the maintenance of middens (Wauters & Dhondt ; Koprowski et al.…”