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The aim of the study was to estimate home range areas and distance of movement away from a squaretail coralgrouper (Plectropomus areolatus) spawning aggregation site located within a small-scale 1.5 km2 Marine Protected Area (MPA) in Pohnpei, Micronesia. Fifteen P. areolatus were acoustically tagged and re-located within a ca. 50 km2 search area over a 4-month period that included reproductive and non-reproductive months. All relocated fish were found in areas of moderate to high coral cover either on the fore reef or inside the lagoon in home ranges of 0.048 ± 0.018 km2 (μ ± S.E.). Variability in home range area (0.004–0.12 km2) and distance of movement from aggregation sites following spawning (0.02–23.0 km; 5.3 ± 3.6 km, μ ± S.E.) was observed, but did not appear to be sex specific. Five of the six relocated individuals were found within 0.02–6.1 km of the aggregation. This evidence and that from recent tag-recapture studies of epinephelids suggest that a substantial proportion of individual P. areolatus spawning populations reside within close proximity to their respective aggregation sites. Reproductive populations could be protected by MPAs of moderate scale (10 s of km2) that include aggregation sites, migratory corridors and adjacent home range habitats.  相似文献   

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Synopsis To determine whether burbot occupy defined home range in rivers, we radio-tracked individuals in the Ohře River, Czech Republic. We also tested the hypothesis that the size of burbot home range would correlate with the fish mass. Burbot's strong attraction to suitable refuges was the basis for our second hypotheses, that its diurnal behavior would reflect refuge availability in the riverine environment. To test these hypotheses, we analyzed data on fish movements in relation to depth, velocity, substratum size and river slope. During the night, burbot preferred deeper areas with lower slope and finer substrates than during daylight hours. The home range was smaller in areas with low or zero slopes, and significantly increased with increasing river slope. There was no relationship between home range size and fish mass. River slope appeared to be the main predictor of the burbot's home range size.  相似文献   

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Home range and habitat use of male Reeves’s pheasant (Syrmaticus reevesii) were studied during winter of 2001~2002 and 2002~2003 in the Dongzhai National Nature Reserve, Henan Province. Results from five individuals of Reeves’s pheasant with over 30 relocations, indicated that the average size of home range was 10.03 ± 1.17 hm2 by Minimum Convex Polygon method, 8.60 ± 0.35 hm2 by 90% Harmonic Mean Transformation method, and 9.50 ± 1.90 hm2 by 95% Fixed Kernel method. It was observed that the winter range is smaller than that in the breeding season. The mean core area of the home range was found to be 1.88 ± 0.37 hm2. Although the habitat composition of the core area varied greatly for individuals, a large part of the habitats used were composed of confier and broadleaf mixed forests, masson pine forests, fir forests, and shrubs. Habitat use within the study area was non-random, while habitats within home ranges were randomly used. Habitat use was dictated by tree diameter at breast height, shrub height and coverage at 2.0 m. The proximity between forests and shrubs were also found to be important in providing refuge for the birds during winter. Recommendations for conservation management include protecting the existing habitats in Dongzhai National Nature Reserve, increasing suitable habitat for Reeves’s Pheasant through artificial plantations (e.g. firs), and restoring some parts of the large shrub area into forests.  相似文献   

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Dragonflies are good indicators of environmental health and biodiversity. Most studies addressing dragonfly ecology have focused on the importance of aquatic habitats, while the value of surrounding terrestrial habitats has often been overlooked. However, species associated with temporary aquatic habitats must persist in terrestrial environments for long periods. Little is known about the importance of terrestrial habitat patches for dragonflies, or about other factors that initiate or influence dispersal behaviour. The aim of this study was to reveal the relationship between population dynamics of the threatened dragonfly species Sympetrum depressiusculum at its natal site and its dispersal behaviour or routine movements within its terrestrial home range. We used a mark–release–recapture method (marking 2,881 adults) and exuviae collection with the Jolly–Seber model and generalized linear models to analyse seasonal and spatial patterns of routine movement in a heterogeneous Central European landscape. Our results show that utilisation of terrestrial habitat patches by adult dragonflies is not random and may be relatively long term (approximately 3 mo). Adult dragonflies were present only in areas with dense vegetation that provided sufficient resources; the insects were absent from active agricultural patches (p = 0.019). These findings demonstrate that even a species tightly linked to its natal site utilises an area that is several orders of magnitude larger than the natal site. Therefore, negative trends in the occurrence of various dragonfly species may be associated not only with disturbances to their aquatic habitats, but also with changes in the surrounding terrestrial landscape.  相似文献   

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Home range and habitat use of male Reeves’s pheasant (Syrmaticus reevesii) were studied during winter of 2001∼2002 and 2002∼2003 in the Dongzhai National Nature Reserve, Henan Province. Results from five individuals of Reeves’s pheasant with over 30 relocations, indicated that the average size of home range was 10.03 ± 1.17 hm2 by Minimum Convex Polygon method, 8.60 ± 0.35 hm2 by 90% Harmonic Mean Transformation method, and 9.50 ± 1.90 hm2 by 95% Fixed Kernel method. It was observed that the winter range is smaller than that in the breeding season. The mean core area of the home range was found to be 1.88 ± 0.37 hm2. Although the habitat composition of the core area varied greatly for individuals, a large part of the habitats used were composed of confier and broadleaf mixed forests, masson pine forests, fir forests, and shrubs. Habitat use within the study area was non-random, while habitats within home ranges were randomly used. Habitat use was dictated by tree diameter at breast height, shrub height and coverage at 2.0 m. The proximity between forests and shrubs were also found to be important in providing refuge for the birds during winter. Recommendations for conservation management include protecting the existing habitats in Dongzhai National Nature Reserve, increasing suitable habitat for Reeves’s Pheasant through artificial plantations (e.g. firs), and restoring some parts of the large shrub area into forests. __________ Translated from Biodiversity Science, 2005, 13 (5) [译自: 生物多样性, 2005,13(5)]  相似文献   

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Background

Although there is evidence to tracking progress towards facility births within the UN Millennium Development Goals framework, we do not know whether women are deciding against home birth over their reproductive lives. Using Demographic and Health Surveys (DHS) data from 44 countries, this study aims to investigate the patterns and shifts in childbirth locations and to determine whether these shifts are in favour of home or health settings.

Methods and Findings

The analyses considered 108,777 women who had at least two births in the five years preceding the most recent DHS over the period 2000–2010. The vast majority of women opted for the same place of childbirth for their successive births. However, about 14% did switch their place and not all these decisions favoured health facility over home setting. In 24 of the 44 countries analysed, a higher proportion of women switched from a health facility to home. Multilevel regression analyses show significantly higher odds of switching from home to a facility for high parity women, those with frequent antenatal visits and more wealth. However, in countries with high infant mortality rates, low parity women had an increased probability of switching from home to a health facility.

Conclusions

There is clear evidence that women do change their childbirth locations over successive births in low and middle income countries. After two decades of efforts to improve maternal health, it might be expected that a higher proportion of women will be deciding against home births in favour of facility births. The results from this analysis show that is not the case.  相似文献   

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James C. Munger 《Oecologia》1984,62(3):351-360
Summary Two aspects of the use of space were studied for two species of horned lizard: (1) Do they restrict their movements to limited areas or do they wander more or less randomly? (2) Is overlap between home ranges reduced below what it would be if home ranges were placed at random with respect to one another?Forty-nine individuals were tagged with radiotransmitters or radioactive tags and their movements compared to a computer-generated random model. It was found that horned lizards typically occupy areas much smaller than they would if they moved randomly, that is, they occupy a limited home range. Home ranges calculated from location points generated by computer randomizations share several characteristics with the limited home ranges of lizards not moving randomly. Randomly derived location points can be surrounded by a minimum convex polygon, or characterized by a probability density function or utilization distribution, and lead to a percent-change in area vs. capture number curve very similar to that shown by lizards not moving randomly. Therefore, none of these techniques distringuishes between home ranges that result from nonrandom use of space and those that result from a randomly moving animal. Previous studies have failed to draw the distinction between these two types of home range. This distinction should be recognized, however, because the underlying processes differ so dramatically.Observed home range overlap was compared with overlap that would be expected if home ranges were located at random with respect to one another. In one of the years tested, reduced overlap was detected at a marginally significant level. This pattern becomes stronger if only overlap with conspecifics is considered. This strongly suggests that home range overlap is reduced between horned lizards. Contrary to expectation, overlap between individuals of opposite sex tended to be less than overlap between individuals of the same sex.  相似文献   

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Fencing conservation areas is ubiquitous in South Africa, however, the impact of these on predator ecology has not been tested. We used relationships between prey abundance and predator space use to create equations to predict the home range size of lions Panthera leo and leopards Panthera pardus. We then successfully tested these predictions using published data (Phinda, Makalali) and home range estimates from radio collared individuals reintroduced to Addo Elephant National Park. Spotted hyaena Crocuta crocuta ranges also seem food dependent. Lion home ranges in Addo (114 ± 5 km2) required 180 fixes to be accurately estimated, spotted hyaena ranges (91 ± 10 km2) required 200 fixes, and the solitary leopard had 295 fixes for a range of 38 km2. There were no sexual differences in home range sizes of lions or hyaenas. The daily food intake rate of lions, measured during continuous follows, was 9.8 kg per female equivalent unit. Dominant male lions (14.3 km for 8.3 kg) traveled furthest but obtained the least amount of food per day compared to subordinate males (8.9 km for 16.0 kg) and females (5.8 km for 17.9 kg). Subordinate males traveled the fastest and during the day, to avoid competition and harassment from the dominant males. From an evolutionary viewpoint, the use of fences for conservation has not affected the natural behaviour of the predators as they still conform to predictions derived from unfenced reserves; that is, prey abundance is the key factor in determining space use of large predators.  相似文献   

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This discussion explores the meaning of ethnographic film with reference to films made by filmmakers “at home.” It is argued that ethnographicness in film is best conceptualized as a continuum, and that anthropology must embrace transnationalism and the changing nature of “homes” and “abroads” in order to present and represent peoples' voices in an era of increasing globalization. It is argued that the way that ethnographic film evolves, as a cultural product and process itself, should be embraced and celebrated for its ability to recognize universal humanity.  相似文献   

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Background

End-of-life care policy has a focus on enabling patients to die in their preferred place; this is believed for most to be home. This review assesses patient preferences for place of death examining: the extent of unreported preferences, the importance of patient factors (place of care and health diagnosis) and who reports preferences.

Methods and Findings

Systematic literature review of 7 electronic databases, grey literature, backwards citations from included studies and Palliative Medicine hand search. Included studies published between 2000–2015, reporting original, quantifiable results of adult UK preferences for place of death. Of 10826 articles reviewed, 61 met the inclusion criteria. Summary charts present preferences for place of death by health diagnosis, where patients were asked and who reported the preference. These charts are recalculated to include ‘missing data,’ the views of those whose preferences were not asked, expressed or reported or absent in studies. Missing data were common. Across all health conditions when missing data were excluded the majority preference was for home: when missing data were included, it was not known what proportion of patients with cancer, non-cancer or multiple conditions preferred home. Patients, family proxies and public all expressed a majority preference for home when missing data were excluded: when included, it was not known what proportion of patients or family proxies preferred home. Where patients wished to die was related to where they were asked their preference. Missing data calculations are limited to ‘reported’ data.

Conclusions

It is unknown what proportion of patients prefers to die at home or elsewhere. Reported preferences for place of death often exclude the views of those with no preference or not asked: when ‘missing data’ are included, they supress the proportion of preferences for all locations. Caution should be exercised if asserting that most patients prefer to die at home.  相似文献   

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