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181.
STEFANO GRIGNOLIO IVA ROSSI ELISA BERTOLOTTO BRUNO BASSANO MARCO APOLLONIO 《The Journal of wildlife management》2007,71(3):713-719
Abstract: Mammalian females change their behavior during the last stages of pregnancy and during the weaning as a response to new energetic requirements and antipredator behavior. From March 2001 to December 2004, we studied the effects of parturition and weaning on home-range sizes and habitat selection in 28 female Alpine ibex (Capra ibex) in a 1,700-ha free area in the Gran Paradiso National Park (Western Italian Alps). We calculated Kernel home range enclosing 95% of each female's locations according to seasonal and bimonthly timescales. Pregnancy did not seem to modify spatial behavior. Lactating females showed smaller home ranges than nonlactating ones after the birth period in June-July. Hot summers slowed kids' growth and prolonged maternal care, modifying mothers' behavior. In summer 2003, which was hotter and drier than usual, weaning females showed even smaller home ranges. Because of their use of antipredator tactics during the weaning season, lactating females showed a higher use of safer habitats, such as rocky slopes. Our results are consistent with the findings of previous cervid and bovid studies, and they suggest that ungulate mothers may move to suboptimal, but safer, habitats during weaning to reduce the predation risk for their offspring. 相似文献
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Does gall diameter affect the parasitism rate of Asphondylia borrichiae (Diptera: Cecidomyiidae)? 总被引:1,自引:0,他引:1
ANTHONY M. ROSSI PETER D. STILING DONALD R. STRONG† DEREK M. JOHNSON 《Ecological Entomology》1992,17(2):149-154
Abstract. 1. Fertilized field plots of Borrichia frutescens (L.) de Candolle produced plants with a higher apical-leaf nitrogen content than control plots.
2. Gall frequency of the cecidomyiid Asphondylia borrichiae Rossi & Strong on stems of B.frutescens , increased significantly on fertilized plots after approximately 3 months.
3. Fertilizer treatment did not result in changes in stem density but did tend to increase proportion of stems flowering and overall plant size. Galls are not normally found on flowering stems.
4. Galls grew at a faster rate and to a larger final size on fertilized plots.
5. On three sampling dates, per cent parasitism of galls was the same on fertilized and control plots; therefore, this study does not support the galldiameter hypothesis. 相似文献
2. Gall frequency of the cecidomyiid Asphondylia borrichiae Rossi & Strong on stems of B.frutescens , increased significantly on fertilized plots after approximately 3 months.
3. Fertilizer treatment did not result in changes in stem density but did tend to increase proportion of stems flowering and overall plant size. Galls are not normally found on flowering stems.
4. Galls grew at a faster rate and to a larger final size on fertilized plots.
5. On three sampling dates, per cent parasitism of galls was the same on fertilized and control plots; therefore, this study does not support the galldiameter hypothesis. 相似文献
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