Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 4

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych:  sexual segregation
help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
The dynamics of spatial distribution was followed in 18 radio-collared male mouflons Ovis ammon musimon (Pallas 1811) belonging to a population living in low mediterranean mountains. It was greatly modified with age and a marked inter­individual variability was observed in young males. The modification of spatial behav­iour appeared to be based on the process of progressive segregation of the sexes outside the rutting period. Spatial distribution by adult males seems to be more structured. However, ceHain males of at least 4 years of age were seen to be sedentary throughout the annua] cycle which suggests that the social segregation of the sexes does not necessarly involve spatial segregation. The hypothesis of neotenization in males of the genus Ovis is supported. The rut gTound is used with fidelity, being a site of particular spatial attachment, which could be related to the fact that it seems to bo the birth site. Nevertheless, with age, fréquentation of the birth site steadily become reduced to functional use related to rutting activities.
The relationships between availability and quality of food, diet composition and habitat use of female and male chamois herds Rupicapra pyrenaica parva (Cabrera, 1911), were investigated in the Cantabrian Mountains (Spain). The two vegetation types studied were grass-forb and shrub. Grass-forb contained higher crude protein and lower fibre than shrub throughout year (crude protein: 17.2% vs 8.6%, p = 0,018; acid detergent fibre: 27.0% vs 35.8%, p = 0.018). The diet of female and male herds showed more grass-forb than shrub (p = 0.012), however, a discrepancy between site selection and bite selection was found. Generally male herds were found in shrub areas although they mainly chose grass-forb in their diet. Female herds had a higher percentage of grass-forb in the diet than male herds throughout the year (81.6% vs 65.6%). Diet composition pattern was similar in both sexes, with a peak of grass-forb in spring and autumn, and a minimum in summer. Both sexes selecLed grass-forb throughout the year, but its use was increased when its quality was high, inde­pendently of quantity available. Females showed higher grazing activity than males throughout year (53% vs 37%, p < 0.0001). Male herds showed less grazing activity during the rut (October-November) in comparison with the rest of the year (25% vs 43%, p < 0.0001). Some hypotheses to explain the segregation of the herds of both sexes are presented and discussed.
Radiotracking of three couples of polecats Mustela putorius Linnaeus, 1758 in wetlands of western France showed that the monthly home ranges of male averaged 0.426 km2 and overlapped the females' ranges which were smaller (0.125 km2). Although the distribution of polecat's localizations in the three main habitats differed significantly between the male and the female, the seasonal overlap of habitat niches (Cjk) was considerable and varied from 0.727 to 0.894. The proportion of simultaneous localizations on the same square averaged 4% of monthly localizations while 96% of the localizations indicated solitary activity. Also, the duration of time occuring together was short: only 1.8 days per month on average. The observations suggested that the social organization of M. putorius was characterized by periodic variations of intra- specific tolerance between males and females which were probably influenced by hormonal factors during spring and by food availability during summer and autumn. A strong spatio-temporal segregation, however, determined a particularly individual exploitation of the space.
The main aim of this study was to determine the numbers, population structure and seasonal changes in group structure of argali Ovis ammon karelini Severtzov, 1873 in the Tian-Shan of Kyrgyzstan. The study was carried out within two adjoining areas: the Baralbas River region, and the Ak-Tash River region. Data were collected during three seasons: winter, spring and summer. This population consisted of 42.3% females, 22.2% males, 13.4% yearlings, and 22.1% lambs. Composition and numbers of groups were seasonally changing. Argali occurred predominantly in mixed groups during winter and exclusively in separated groups during summer. The maximum group size decreased from 25% from winter to spring, however, increased during summer.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.