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1

Home ranges in red fox: territoriality diminishes with increasing area

100%
Goszczynski J.
Acta Theriologica. Supplement
|
2002
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tom 47
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nr 1
Red fox Vulpes vulpes (Linnaeus, 1758) are generally regarded as strictly territorial animals, inhabiting distinct and well-separated ranges. The home ranges of these predators can vary in size from a few dozen hectares to as much as 20-30 km2. Because it seemed impossible that foxes could defend areas so different in size with the same intensity, the published data were analysed in order to see how changes in home range size could affect the following parameters: home range overlap, the area visited daily and the distance travelled by animals during 24 h. It was found that the overlap between fox families (groups) occupying large ranges was much greater than between foxes living in small ranges. The ratio of the area visited daily to the seasonal home range size was greater in small ranges than in large ones. No significant correlation was found between the mean distance moved daily and home range size (r = -0.118, p = 0.75). These results suggest different patterns of the use of space and differences in territorial defence by red foxes inhabiting large and small ranges. The implications of home range overlap and intensity of contacts between foxes occupying neighbouring ranges for the spread of disease are discussed. The significant overlap between large ranges found in this paper is discussed in the light of Andrzejewski's (2002) home range concept.
2

Factors affecting home range size and overlap in Akodon azarae [Muridae: Sigmodontinae] in natural pasture of Argentina

100%
Priotto J. W., Steinmann A. R.
Acta Theriologica
|
1999
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tom 44
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nr 1
Differences in home range size in relation to sex, age, breeding and non-breeding periods were studied Home range size and overlap were examined at different den­sities values in populations of Akodon azarae (Fischer, 1829) on railway banks in southern Cordoba Province (Argentina). The sampling was carried out between October 1994, and February 1997, using the capture-mark-recapture method. Home range size in A, azarae was determined by sex and breeding period, and it was independent of the observed density values. Home range size of males was always larger than that of femaies. Increase of population density during the breeding period affected the degree of intersexual overlap of home range,
3

Spatial organization and social relations in the Eurasian lynx population in Bialowieza Primeval Forest, Poland

84%
Schmidt K., Jedrzejewski W., Okarma H.
Acta Theriologica
|
1997
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tom 42
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nr 3
The home range size, spacing pattern and intraspecific relations in the lynx Lynx lynx (Linnaeus, 1758) were studied in Białowieża Primeval Forest (eastern Poland), in 1991-19S6. Eighteen lynx (11 males and 7 females) were captured and radio­-collared. The mean autumn-winter home range size was 165 km2 for males and 94 km2 for females. In spring-summer, it was 143 and 55 km2, respectively. The mean life-time home ranges were 248 km" for males and 133 km* for females. Male home range size did not change significantly between autumn-winter and spring-summer seasons, however, their ranges increased by 40-90% just before and during the mating season (December-March). The home range of females in the autumn-winter season was almost twice as large compared with the spring-summer period (94 vs 55 km2). The smallest home ranges were observed in breeding females during the two months after parturition (10 kmJ) and these grew until the following spring. The home ranges calculated for 5-month periods shifted on average 4 km in adult males, 2.7 in adult females and 4.7 km in subadult males. One of the farthest shifts in the adult male range (8.7 km) was explained by the death of a neighbouring resident. The average overlap between adult males' ranges was 30%, while those between females was 6%. The largest overlap occurred between adult males and females (62%) as well as between adult and subadult males (75%). The lynx showed a tendency to avoid each other. The average distance between neighbouring adult males was 11.6 km, and they were never found closer than 1 km to each other. The average distance between neighbouring females was 8.1 km. Besides a few meetings between males and females (during and outside the mating season), they were located separately (4.4 km from each other, on average), in 93% of the cases an adult female was recorded with her dependent kittens. It was concluded that home range size and spacing pattern in male lynx depend on the distribution of females, whereas spacing in females was determined by food-related factors.
4

Size and overlap of home range in Calomys musculinus [Muridae: Sigmodontinae]

84%
Steinmann A. R., Priotto J. W., Castillo E. A., Polop J. J.
Acta Theriologica
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2005
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tom 50
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nr 2
Home range size and overlap ofCalomys musculinus (Thomas, 1913) was examined in relation to sex and breeding periods. The study was carried out in four 0.25 ha enclosures, in a natural pasture, between October 2002 and July 2003. The four enclosures functioned as independent populations and each was considered a replicate. The capture, mark and recapture method was used. Home range size and overlap inC. musculinus depended on sex and period. Home range size of males was always larger than that of females. Females showed a small degree of intra-sexual home range overlap during the breeding period. In general, male home ranges overlapped with females. We conclude that differences in home range size inC. musculinus is determined by sex and breeding period. Moreover, the degree of inter- and intra-sexual home range overlap during the breeding period suggests that both males and females ofC. musculinus use space differently. Females did not share their home range with other females, while males fully shared it with both sexes, and male spacing is influenced by the distribution of females. A promiscuous-polygynous mating system is suggested forC. musculinus.
5

Spatial niche overlap between vicunas and guanacos

84%
Lucherini M., Birochio D., Marinelli C., Legato A. M.
Acta Theriologica
|
2000
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tom 45
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nr 1
Through the analysis of habitat use in free-ranging, sympatric guanacos Lama guanicoe (Müller, 1776) and vicuñas Vicugna vicugna (Molina, 1782), we tested whether spatial segregation between the two species occurred in a high-altitude (4000-5000 m) Andean ecosystem, North-Eastern Argentina. Puma presence was recorded in only one of the two summers when data were recorded. Therefore, we also tested the effects of predation risk on camelid habitat use and overlap. The two camelids adopted a very similar space use strategy, but guanaco tended to be observed more frequently than vicuñas in the forage-rich patches in close proximity to water. The three different social units, characterising the organization of both wild camelids, had partially different habitat uses and the variations between them contributed to narrow the extent of spatial overlap between species. In response to increased predation risk, camelids decreased the use of the areas where most signs of hunting activity occurred. Predatory pressure had a levelling effect in habitat use variation, thus further reducing inter­-specific segregation.
6

Factors affecting the variability in home range size and distribution in European bison in the Polish and Belarussian parts of the Bialowieza Forest

84%
Krasinska M., Krasinski Z. A., Bunevich A. N.
Acta Theriologica
|
2000
|
tom 45
|
nr 3
The size and spatial distribution of home ranges of the European bison Bison bonasus (Linnaeus, 1758) in the Polish and Belarussian parts of the Białowieża Forest were studied in the years 1993-1998. In this period, 28 bison (18 males and 10 females) aged 4-10 years, including 20 (15, 5) from the Polish part of the Białowieża Forest and 8 (3, 5) from the Belarussian part, were radio-collared. The mean size of winter home ranges of bulls was 10.7 km (range 0.8-32.2, n = 25) while that of cows was 7.9 km (range 0.7-34.3, n = 15), difference between the sexes not being significant. The size of winter home ranges was significantly correlated with the duration of snow cover and with the mean daily temperature in winter (R = 0.311, p = 0.001). Long-Sasting snow cover and low temperatures significantly limited bison mobility in the forest. In the snow-free season, the mean size of home ranges of bulls was 69.5 km (range 29-151.6) and that of cows was 68.8 km (range 45.4-97.5), the difference not being statistically significant. The size of bulls' home ranges in the snow-free period was related to their age. The mean size of home ranges of younger adult bulls was 44.0 km , being significantly smaller than the ranges of older adult bulls (84.3 km ) and cows. European bison used their ranges unevenly and showed individual spatial fidelity in subsequent years. Home ranges of the European bison of both sexes were not defended and overlapped extensively. Food abundance of remarkably diverse habitats (forest, meadows) had a significant effect on the size of bison home ranges. In August-October, home ranges of cows from the Polish populations penetrating the forest averaged 45.5 km and were significantly larger than the ranges of cows from the Belarussian population foraging on meadows (24.3 km ).
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