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We studied demography and spatial organization in a population of root voles Microtus oeconomus (Pallas, 1776) inhabiting a fenced, linear habitat (560 x 1.5 m) during the breeding season, using live trapping and radiotelemetry. There were no establishments of new reproductive individuals. Compared to root voles in non-linear habitats, home ranges were extremely small and no male home ranges overlapped. A short term removal and reintroduction experiment (2 days removal of every second individual on the study area) produced no changes in home range size, indicating that home range borders were not defended by daily contact between neighbours.
We radiotracked 7 European mink Mustela lutreola Linnaeus, 1761 (5 males and 2 females), to determine their distribution, size and temporal changes of their home range in an area of southwestern Europe, where American mink M. vison was not established. Size of home ranges varied from 11 to 17 km along watercourses in males and were 0.6 and 3.6 km in females. Home ranges of males were larger than those found in previous studies. Most females captured (either radiotracked or not) were found within the home range of males. Males occupied adjoining river sections with minimal range overlap, suggesting an intrasexually exclusive spacing pattern for males. Each month males used new river stretches, mainly along tributaries; meanwhile they showed a steady use of their stem river section. Resting sites were mainly beneath dense brambles of Rubus patches located in the river bank.
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.
Habitat and spatial organisation of 11 radio tagged Eurasiani lynxes Lynx lynx Linnaeus, 1758 were studied in a low-density (ca 0.3 ind/100 km ) population in a boreal-alpine environment with low and temporally varying densities {< 180 ind/100 km in winter) of ungulate prey, primarily roe deer and semi-domestic reindeer. The use of habitat measured as 4 biome categories ranked from south boreal to alpine influenced mountain vegetation did not vary seasonally, but lowlands were much preferred to alpine habitats. Adult males moved almost 3 times farther per day in linear distance (x = 5.9 km, n = 3) than did females with kittens ix = 2.0 km, n = 4) or subadult females (x = 2.5 km, n = 6; p = 0.002). Subadults (n = 5) dispersed 42 ± 13 (x ± SE) km during the first 9 months of independence, but often visited their natal range during the first year on their own. Adult lynxes roamed over very large annual ranges [males: 1906 ± 387 km (n = 4), females: 561 ± 102 km2 (n = 6)J that took > 5 days to pass through, independently of sex. The oniy male monitored over more than 1 year maintained 2 separate home ranges each year. The larger home ranges and the possible tendency towards less defined territory boundaries than previously reported for the species, may be caused by the lower prey and population densities, though culling of adult individuals may also have played a role by continuously creating empty gaps in the territorial mosaic.
The patterns of social behaviour and spatial structure of Crocidura leucodon (Hermann, 1780) were studied against the background of the seasonal changes in its density and demographic features. Field and lab research were conducted. Field investigations (with CMR method) were conducted from 1997 to 1999 in north-western Bulgaria, in a grassland with patches of tree-shrub vegetation. In the lab, the social interactions were studied in male-male, female-female and male-female dyadic encounters during summer and autumn. A total of 26 shrews were tested. The number of C. leucodon was lowest in spring and greatest in autumn. In early summer the sex ratio was balanced, the home range of one male overlapped that of one female, and aggressiveness and marking activity was increased. So, it can be assumed that in this period males and females form pairs, which possess defended territories. Higher aggressiveness and marking activity displayed by males suggest their greater role in defending the territories. In autumn the home ranges overlapped greatly and amicable interactions prevailed over agonistic ones probably due to shifting to a gregarious way of life. So, the patterns of spatial structure and social behaviour undergo the seasonal changes in C. leucodon life-cycle and its density dynamics.
Peptidoglycan (PG), the mighty miniwall, is the main structural component of practically all bacterial cell envelopes and has been the subject of a wealth of research over the past 60 years, if only because its biosynthesis is the target of many antibiotics that have successfully been used in the treatment of bacterial infections. This review is mainly focused on the most recent achievements in research on the modification of PG glycan strands, which contribute to the resistance of bacteria to the host immune response to infection and to their own lytic enzymes, and on studies on the spatial organization of the macromolecule.
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