Cransac N, Hewison A J
Institut de Recherche sur les Grands Mammiferes, INRA, BP 27, 31326 Castanet-Tolosan Cedex, France.
Behav Processes. 1997 Oct;41(1):57-67. doi: 10.1016/s0376-6357(97)00033-8.
We studied seasonal habitat use of female, mixed-sex and male groups in a free-ranging mouflon (Ovis gmelini) population. The three group types differed in the use of the five different habitats (forests, broom moorlands, heather moorlands, meadows and rocky areas) only in spring (lambing period) and in autumn (rutting period). To study habitat selection, we compared the proportion of groups observed in each habitat type with the proportion of each of these habitat types sampled. This revealed that, for the four seasons, all three group types selected certain habitats. Overall, mouflon selected meadows and/or broom moorlands, but male groups switched to forests in spring and autumn. We examined this pattern of habitat selection in relation to shelter value and feeding activity for the three group types. Wind strength played a role in determining patterns of habitat use during the climatic extremes of winter and summer. Male and female groups consistently fed in the same habitat types, even though they did not select the same habitats in spring and autumn and despite a marked segregation between the sexes in this population. Two commonly cited hypothesis for explaining sexual segregation based on sexual size dimorphism and on alternative reproductive strategies of males and females were not supported by our results. We suggest that simple behavioural mechanisms may suffice to explain sexual segregation in this population.
我们研究了自由放养的摩弗伦羊（欧洲盘羊）种群中雌性、混合性别和雄性群体的季节性栖息地利用情况。这三种群体类型仅在春季（产羔期）和秋季（发情期）对五种不同栖息地（森林、金雀花荒地、石南荒地、草地和岩石区域）的利用上存在差异。为了研究栖息地选择，我们将在每种栖息地类型中观察到的群体比例与所采样的每种栖息地类型的比例进行了比较。结果表明，在四个季节中，所有三种群体类型都选择了特定的栖息地。总体而言，摩弗伦羊选择草地和/或金雀花荒地，但雄性群体在春季和秋季会转向森林。我们针对这三种群体类型，研究了这种栖息地选择模式与庇护价值和觅食活动的关系。在冬季和夏季的极端气候条件下，风力在决定栖息地利用模式方面发挥了作用。雄性和雌性群体始终在相同的栖息地类型中觅食，尽管它们在春季和秋季没有选择相同的栖息地，且该种群中存在明显的性别隔离。我们的结果不支持两种常见的基于性别体型差异和雄性与雌性不同繁殖策略来解释性别隔离的假说。我们认为简单的行为机制可能足以解释该种群中的性别隔离现象。
