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263.
Movements of brown rats were deduced from records made during a capture-recapture study of rural populations on two farms in Mid-Wales. Populations in the hedges were sampled at monthly intervals for two years, but samples from the farm buildings were obtained only irregularly and by a variety of methods.
On the main trap line, of the rats captured during at least two sampling periods 35 (78%) females and 57 (74%) males appeared to have established home ranges, the best estimates of mean home range length for each sex being 54.8 m and 66.1 m respectively. The longest recorded distances travelled during known life were 850 m for a female and 954 m for a male, although the median distances travelled were only 43 m and 52 m respectively. The median distance travelled during a sampling period (seven nights) was about 24 m for both sexes. There were no significant differences between the distances travelled by the sexes or by different age groups, and there was little seasonal variation.
Infestations in the hedges were always associated with streams, and those more than about 100 m from the buildings seldom persisted through winter. During autumn and winter the rats in the more distant localities tended to move towards the buildings, but there was no suggestion of an orderly migration. Twenty-seven out of 386 rats marked in the hedges were recovered amongst 576 taken from the buildings, but only nine of diem had travelled more than 100 m. No rats released in the buildings were captured in the hedges. Rats established in the buildings seemed to exclude rats immigrating from the hedges.  相似文献   
264.
BackgroundThe intensity of the home care interventions for dependent older people offered in Spain may not be sufficient to help keep older people living at home, being the institutionalization in a nursing home (NH) an unavoidable consequence.ObjectiveTo evaluate the effect of intensification in home care interventions on users with grade II or III dependency, as well as training for their informal caregivers in order to delay or avoid their institutionalization in a NH.MethodsA randomized clinical trial with two parallel arms and blinded assessment will be conducted at the community level in two municipalities in Catalonia (Spain). The study will include those older people (aged 65 and over) living in the community, with degree II or III of dependency, users of the public home care unwilling to be institutionalized and with a main informal caregiver in charge, who will also participate in the study. The assessments will be performed monthly up to 15 months, when the intervention will be finished. The main outcome will be the time until the willingness for admission to a NH. Secondary variables will be composed of sociodemographic, health, psychosocial, resource use, and follow-up variables. A multivariate Cox regression model will be carried out to estimate the effectiveness of the intervention.DiscussionA multimodal home care intervention could improve the health and psychosocial status of dependent people and their informal caregivers and facilitate their permanence at home.Trial registrationNCT05567965  相似文献   
265.
Summary Intraspecific and intrasexual variation in home range size, body mass and ecological productivity is examined in three selected species of Carnivora (Felis rufus: Canis latrans; Ursus americanus), reflecting different diets. We then compare the intraspecific results with prior cross-species studies. Home range size and body mass inFelis rufus are positively and significantly correlated, similar to other comparative studies. For both intraspecific and intrasexual analyses of all three species, home range size and latitude are strongly correlated. Home range size scales with latitude more steeply as the proportion of meat increases in the diet of each species. That is, the slope of home range size on latitude is greatest in the meat-eatingFelis rufus followed by a shallower slope in the omnivorousCanis latrans and the most shallow slope in the frugivorous/folivorousUrsus americanus. These differences in slope are consistent with models of trophic level biomass change with variation in productivity, and parallel the dietary differences observed in cross-species differences in home range.  相似文献   
266.
We examined the patterns of habitat use of six radio-tagged booted eagles (Hieraaetus pennatus) in a Special Protection Area (SPA) in southeastern Spain. Variable percentages of radio locations (20.8–72.0 %) and home range areas (45.2–81.3 %) lay outside the SPA limits. A model selection procedure showed that habitat use was mainly influenced by habitat type and the distance to the nest. Edges and open lands were the most selected habitat types at long distances, while the probability of forest use strongly decreased with the distance. We conclude that effective conservation strategies for this species should encourage not only the protection of the forest nesting habitats, but also the traditional agricultural practices of the surrounding agroecosystems.  相似文献   
267.
Home areas of hosts are, in effect the gardens in which parasite populations grow. The parasites flourish in response to the kind and amount of host activity modified, of course, by the habitat, and become microcommunities supported by their host and its artifacts. When scatter diagrams of points at which hosts have been observed are divided by median major and minor axes, and when the resulting four quarters, designated A, B, C, D, corresponding to concentration of points in the quarters, the relative concentration usually is: A>B>C>D. The concentration of observed points also is generally greatest nearest the major axis and frequently, but not always, near the median center. Nests of hosts, hence nest-parasites, appear generally to be near the center. For the host examined in detail here, the New Guinea coarse-haired rat, most Leptotrombidium deliensis appear to have been acquired in the AB sector of the host's home areas but a greater diversity of chiggers is acquired in the CD sector. It is postulated that, if L. akamushi had been present, it would have occurred in the CD sector where, though the observed concentration of host activity was least, the mixed grassforb and shrub habitat would have been more suitable than in the AB sector. Gahrliepia pingue, C. ewingi, Schoengastia blestowei and S. schueffneri, appear also to be more abundant in the CD sector than in the AB sector. The chiggers themselves have home clusters, or lairs, and adjacent areas of activity (home areas) somewhat resembling those of the hosts.  相似文献   
268.
Home range (HR) size and overlap, movements, and nest site use of fat dormice Glis glis (Linnaeus, 1766) were studied by live-trapping and radiotracking in the Bialowieza Forest in north-eastern Poland. The study was conducted during a mast year of oak Quercus robur (2001) and hornbeam Carpinus betulus (2002). Average HR size measured by 100% minimum convex polygons varied from 3.6 to 7.0 ha in males and from 0.55 to 0.76 ha in females. HR size in males was significantly larger in the hornbeam mast year than in the oak mast year, which was probably due to the lower energy value of hornbeam mast. Males had significantly larger HRs and used more nest sites than females. In contrast to females, HRs of males overlapped extensively. In the mating season, core areas of males overlapped significantly more and they shared their core areas with more males than in the post-mating season. During the mating season, males were found to share nest sites with other males or with a single female. Additionally, groups of 2–3 males were observed aggregating around a female during the mating season. Our data suggest that fat dormice have a promiscuous mating system where the females are territorial, and the non-territorial males directly compete for access to receptive females during the mating season.  相似文献   
269.
This study examines the short-term site fidelity, the home range size and the activity patterns of one specimen of the emblematic and threatened humphead wrasse, Chelinus undulatus. Four omnidirectional hydrophones were deployed for 7 months in the mooring area of Larégnère marine reserve (New Caledonia). The hydrophone network covered 50 ha. The monitored fish was caught in the study site and surgically implanted with an ultrasonic transmitter. The fish displayed a regular diurnal rhythm during 25 days before leaving the area. Different patterns of spatial use were identified. The temporal succession of these patterns indicates that the minimum distance covered by the fish every day ranged between 20 and 200 m. Its home range was at least 5 ha. A decrease of the detection was observed before the departure of the fish. This decrease coincided with the beginning of the reproduction period in New Caledonia and supports the hypothesis of a fish departure for the reproductive event. Despite the survey of only one specimen, the home range and movement calculated using acoustic telemetry are different in scale than the reported scuba-based visual estimations. Such information is essential for the development of management policies and conservation measures of large reef fish species highly vulnerable to disturbance and fishing pressure.  相似文献   
270.
Summary I increased the availability of tadpole-rearing sites (bromeliads) and oviposition sites (leaf litter) and examined the effects on space-use patterns in adult Dendrobates pumilio at the La Selva Biological Reserve in northeastern Costa Rica. I made 4158 observations of 986 marked adults during the seven-month study period. The addition of leaf litter did not result in increased density, but the addition of bromeliads did. The addition of leaf litter resulted in increased home-range size, but the effect depended on bromelial addition and sex. Home-range size was greater for females than males, and may be related to parental care and/or mate selection. Home-range size was not correlated with density. Spatio-temporal overlap was not affected by resource supplementation but the proportion of females captured in sites shared with males varied temporally. Dispersion was no affected by bromeliad supplementation but males on litter-addition plots were less clumped than males on other plots. These results indicate that the density increase observed on bromeliad-addition plots was accommodated by frogs utilizing previously unoccupied space. Frogs were captured more frequently at bromeliads on bromeliad-supplemented plots than on litter-addition and control plots. The size of the area defended by territorial males is smaller than home-range size indicating the absence of home-range defense.  相似文献   
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