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1.
Chimpanzees and gorillas are the two most common species of great ape in captive facilities in North America. This study examined patterns of space use by 14 gorillas and six chimpanzees housed in similar non-naturalistic environments at Lincoln Park Zoo in Chicago, IL. The location of each individual was recorded in relation to elements of the environment over a two-year period. These data were compared to volumetric measurements of the enclosures to determine “preferences” for particular environmental elements. Chimpanzees preferred the highest tier of the enclosure and the gorillas preferred the floor level. Both species showed preferences for doorways, corners and the mesh barriers adjacent to keeper areas. These data supplement data from wild populations of apes and provide information useful for those seeking to design new ape enclosures or renovate existing facilities.  相似文献   

2.
This research was carried out to examine the hypothesis that the absence of fathers promotes a different spacing behaviour in juveniles Calomys musculinus at the beginning of the breeding period. The study was carried out in four 0.25-ha enclosures (two control and two experimental), in a natural pasture, between November 2003 and February 2004. In this study the fathers were removed from the experimental enclosures after juveniles were born. Home-range size depended on sex of juveniles and treatment (father removal). In control and experimental enclosures, female home-range sizes were always smaller than male home-ranges. Male home-ranges were always larger in experimental enclosures than in control enclosures. Treatment and overlap type (intra- and inter-sexual) were not independent. The overlap proportions of male home-ranges were greatest in experimental enclosures than in control enclosures, in both the overlap types (male/male, males/females). The intra- (females/females) and inter-sexual (females/males) overlap proportions of female home-ranges were independent of treatment. In C. musculinus, at the beginning of the breeding period and in absence of adult males, juvenile males increase their home-range size and therefore the degree of inter- and intra-sexual home-range overlap as a mechanism for enlarging the number of receptive females that they encounter.  相似文献   

3.
Culturally protected forest patches or sacred groves have been the integral part of many traditional societies. This age old tradition is a classic instance of community driven nature conservation sheltering native biodiversity and supporting various ecosystem functions particularly hydrology. The current work in Central Western Ghats of Karnataka, India, highlights that even small sacred groves amidst humanised landscapes serve as tiny islands of biodiversity, especially of rare and endemic species. Temporal analysis of landuse dynamics reveals the changing pattern of the studied landscape. There is fast reduction of forest cover (15.14–11.02 %) in last 20 years to meet up the demand of agricultural land and plantation programs. A thorough survey and assessment of woody endemic species distribution in the 25 km2 study area documented presence of 19 endemic species. The distribution of these species is highly skewed towards the culturally protected patches in comparison to other land use elements. It is found that, among the 19 woody endemic species, those with greater ecological amplitude are widely distributed in the studied landscape in groves as well as other land use forms whereas, natural population of the sensitive endemics are very much restricted in the sacred grove fragments. The recent degradation in the sacred grove system is perhaps, due to weakening of traditional belief systems and associated laxity in grove protection leading to biotic disturbances. Revitalisation of traditional practices related to conservation of sacred groves can go a long way in strengthening natural ecological systems of fragile humid tropical landscape.  相似文献   

4.
In order to investigate whether density affects dispersal, carabid beetles of two species, Harpalus rufipes (Degeer) and Pterostichus niger (Schaller), were released separately in six and two field enclosures, respectively. The enclosures were 4 m2 each and located in an oat field. The former species was released in seven densities, each with 12 replicates and the latter in five densities each with four replicates. Beetles leaving the centre of the enclosures were captured in pitfall traps along a 1 m wide strip of bare soil. Logistic models were fitted to the data. There were no significant effects of the density treatment variable on P. niger. For H. rufipes the best model was obtained by specifying the density treatment as a nominal variable. The deviance accounted for by this model was highly significant. There were, however, no consistent trends for either species with respect to the density treatment. The inclusion of climatic variables, the number of new beetles introduced at the onset of each trial, or the date of the trial did not improve the fit of any of the models. It is concluded that density did not significantly increase dispersal in the two species. It thus appears that a possible increase in behavioural interactions (i.e. interference competition) did not increase the dispersal in adults of the two species examined in this experiment.  相似文献   

5.
Cattle on the Golan Heights are kept in enclosures and some of these enclosures have guard dogs. We studied the effect of such dogs on the behavior and breeding success of mountain gazelles Gazella gazella living within enclosures. We found that guard dogs have both direct and indirect effects on gazelles. Gazelles living in enclosures with dogs spent more time in vigilance behavior and running, and less time resting and walking, in comparison with gazelles in dog-free enclosures. In the absence of dogs, gazelle female herds in enclosures tended to stay closer to the cattle, but shunned away from them in the presence of the dogs, which, in turn, remained near the cattle. The percentage of fawns per female was higher in enclosures without dogs in comparison with those with dogs, but the difference was not significant. However, the largest of the enclosures with dogs, which had the largest number of gazelles, had only an average number of dogs in it. Hence, the gazelles in this enclosure were better able to avoid the dogs in comparison with those in smaller enclosures. Removing this enclosure from the overall calculation revealed that guard dogs have a significant negative effect on gazelle reproductive success. In two of the four enclosures with dogs no fawn still survived 6 months after birth, while in each of the four enclosures without dogs some fawns did survive to that age and beyond, suggesting that the dogs themselves may predate the fawns.  相似文献   

6.

Background

This paper proposes an approach to estimating the costs of demand creation for voluntary medical male circumcision (VMMC) scale-up in 13 countries of eastern and southern Africa. It addresses two key questions: (1) what are the elements of a standardized package for demand creation? And (2) what challenges exist and must be taken into account in estimating the costs of demand creation?

Methods and Findings

We conducted a key informant study on VMMC demand creation using purposive sampling to recruit seven people who provide technical assistance to government programs and manage budgets for VMMC demand creation. Key informants provided their views on the important elements of VMMC demand creation and the most effective funding allocations across different types of communication approaches (e.g., mass media, small media, outreach/mobilization). The key finding was the wide range of views, suggesting that a standard package of core demand creation elements would not be universally applicable. This underscored the importance of tailoring demand creation strategies and estimates to specific country contexts before estimating costs. The key informant interviews, supplemented by the researchers'' field experience, identified these issues to be addressed in future costing exercises: variations in the cost of VMMC demand creation activities by country and program, decisions about the quality and comprehensiveness of programming, and lack of data on critical elements needed to “trigger the decision” among eligible men.

Conclusions

Based on this study''s findings, we propose a seven-step methodological approach to estimate the cost of VMMC scale-up in a priority country, based on our key assumptions. However, further work is needed to better understand core components of a demand creation package and how to cost them. Notwithstanding the methodological challenges, estimating the cost of demand creation remains an essential element in deriving estimates of the total costs for VMMC scale-up in eastern and southern Africa.  相似文献   

7.
The nonindigenous sacred ibis (Threskiornis aethiopicus) was first discovered breeding in the Florida Everglades in 2005 in the Arthur R. Marshall Loxahatchee National Wildlife Refuge. Prior to this, sacred ibises were seen periodically throughout South Florida since the mid 1990s, with occasional confirmed breeding occurrences in Miami-Dade and Palm Beach counties. We used a logistic regression model developed by Allen (Biol Invasions 8:491–500, 2006) to predict the probability of successful establishment of sacred ibis in the Florida Everglades ecosystem. Empirical data collected from several sacred ibis nests and chicks were used to validate those findings. The probability of successful establishment was estimated to be 73%. The physiological condition of nestlings suggested that this species was able to fledge chicks in good condition, thus adding to the potential to increase their breeding population. Exponential population growth rates and expanding distribution of the nonindigenous sacred ibis in France demonstrate this species’ potential for becoming invasive in Florida. We suggest that the most prudent and effective management strategy is eradication of the few pioneering individuals that are nesting in the Everglades as well as the urban source population.  相似文献   

8.
The influence of zooplanktivorous fishes on the plankton community and water quality of Americana Reservoir, Brazil was studied experimentally in 4 floating enclosures during the dry seasons (July–September) of 1982 and 1983. Two enclosures were stocked with adult fish (Astyanax bimaculatus in 1982;A. fasciatus in 1983) at near maximal densities measured in the reservoir upper surface waters (35 m–2) and two were fish-free during each experiment lasting about one month. Marked differences were evident between the fish and fish-free enclosures after a 2–3 week period in each experiment, particularly with respect to water transparency, phytoplankton biomass, and zooplankton abundance as well as species and size composition. By the end of each experiment water transparencies were lower and phytoplankton biomass higher in the fish enclosures compared to those without fish. Also at that time Rotifera were the prominent zooplankters in the fish enclosures and Cladocera in the fish-free ones. Larger or more conspicuous species of Cladocera asDaphnia gessneri, D. ambigua, andMoina micrura were present in the fish-free enclosures but not in the fish enclosures. The interactions between fish predation, zooplankton grazing, phytoplankton biomass and water quality conditions are discussed in relation to eutrophication of a tropical aquatic ecosystem.  相似文献   

9.
The ground beetle Pterostichus melanarius (Coleoptera, Carabidae), of European origin, is abundant and wide-spread in the northern United States and southern Canada Three field enclosures were used in a four-year experiment in Alberta, Canada, to examine whether the species is able to establish in natural aspen-poplar forest, and to test the hypothesis that it has an adverse effect on the native carabid assemblage After introduction to the enclosures P melanarius maintained breeding populations in them, establishing that the forest is suitable habitat for the species, and suggesting that the species will eventually invade from nearby populations Pterostichus melanarius had no negative effect on population size or body mass of the native carabid species However, the two most abundant native species (Ptero-stichus adstrictus and P pensvlvanicus) appeared to be more active (measured as escape rate) in compartments where they co-occurred with P melanarius Although the three enclosures were just a few metres apart, one of them consistently yielded the highest densities of all carabid species This difference was correlated with high abundance of earthworms and low litter accumulation Relatively low densities of P melanarius may explain the lack of negative interspecific interactions in forests, although such effects are suggested by data from urban and agricultural environments where P melanarius is more abundant  相似文献   

10.
André Iteanu 《Ethnos》2013,78(3-4):169-183
The study of rituals raises the issue of the formulation of the sacred‐profane distinction. If sacred and profane are considered as mutually exclusive, this distinction is not applicable to Melanesian societies. However, a re‐reading of Durkheim's work reveals an alternative formulation derived from two distinct forms of hierarchy: gradation and encompassment. Dumont's analysis of the caste system permits us to reconcile these two forms, which then appear as governed by a unified hierarchy of values. This reformulated, hierarchic definition of the sacred‐profane relation is tested on the Orokaiva case. Finally, it allows us to draw certain comparative conclusions.  相似文献   

11.
As in several Central European areas, in the Bohemian Forest Ecosystem (Germany and the Czech Republic), fenced feeding enclosures are used for the winter management of red deer (Cervus elaphus), which is an important component of the Eurasian lynx’s (Lynx lynx) winter diet. Using GPS telemetry data, we tested whether (1) lynx hunted red deer mainly selecting for high prey densities and environmental characteristics like a good level of habitat heterogeneity, independently of the enclosures’ presence; (2) enclosures attracted lynx and (3) positively influenced their predation on red deer, being predictable and abundant prey sources throughout the winter; or (4) extremely high deer densities inside the enclosures rather negatively influenced lynx predation on this species. We first compared lynx space usage and predation on red deer inside and outside the enclosures. Then, we investigated the effects of the environment, prey densities and the enclosure distance for the area outside of enclosures. Prey densities positively influenced lynx space usage, whilst the probability of predation on red deer was highest at medium to low red deer densities. Habitat heterogeneity and terrain ruggedness influenced both lynx space usage and probability of predation on red deer. Regarding the effect of enclosures, the ratio “area used during night vs. daytime” was larger by a factor of 2 inside compared to outside enclosures, and the probability of predation on red deer was three times higher inside rather than outside of enclosures; however, these differences were not statistically significant, suggesting that the influence of the enclosures is not very pronounced.  相似文献   

12.
Expansion of coffee cultivation is one of the causes of deforestation and biodiversity loss. However, shade grown coffee has been promoted as a means for preserving biodiversity in the tropics. In this study we compared tree diversity in two types of coffee management regimes with the sacred groves in the Western Ghats of India. We computed species accumulation curves, species diversity indices and evenness indices to compare the different management regimes. Results of diversity indices showed that shade coffee had less diversity compared to sacred groves. Exotic species dominated the tree diversity in lands where the tree harvesting rights are with the growers. Native trees dominated the tree diversity when growers had no ownership rights on trees. A species accumulation curve suggested that the sacred grove had higher species richness compared to other two habitats. Lack of incentive to preserve endemic species as shade trees is forcing growers to plant more exotic species in shade grown coffee plots. If encouraged, shade grown coffee can preserve some biodiversity, but cannot provide all ecological benefits of a natural forest.  相似文献   

13.
The effects of planktivorous and benthivorous fish on benthic fauna, zooplankton, phytoplankton and water chemistry were studied experimentally in two eutrophic Swedish lakes using cylindrical enclosures. In enclosures in both lakes, dense fish populations resulted in low numbers of benthic fauna and planktonic cladocerans, high concentration of chlorophyll, blooms of blue-green, algae, high pH and low transparency. In the soft-water Lake Trummen, total phosporus increased in the enclosure with fish, but in the hard-water Lake Bysjön total phosphorus decreased simultaneously with precipitation of calcium carbonate. Enclosures without fish had a higher abundance of benthic fauna and large planktonic cladocerans, lower phytoplankton biomass, lower pH and higher transparency.The changes in enclosures with fish can be described as eutrophication, and those in enclosures without fish as oligotrophication. The possibility of regulation of fish populations as a lake restoration method is discussed.This paper was presented at the XXth SIL Congress in Copenhagen in 1977.  相似文献   

14.
The study was conducted to compare species richness and diversity in different ecosystems and abiotic factors. The results showed that the sacred groves had a plant genetic diversity composed of a total of 42, 65 and 82 ethno‐botanical species of herbs, shrubs and trees, respectively, with varied qualities. There were six herbaceous species common in the fallow ecosystem and the sacred groves, 35 herbaceous species found in the sacred grove and absent in the fallow vegetation and 70 herbaceous species in the fallow vegetation and absent in the ground layer of the sacred groves. Thirty‐two regenerated species and 49 nonregenerated tree species were found in the sacred groves. The herbaceous α‐diversity was significantly higher in the fallows than the sacred groves at the low altitude. The tree species richness was higher at the low altitude compared to the high altitude with tree β‐diversity increasing with altitude. Varying combinations of soil pH, total P, total K, CEC and slope per cent were related to some of the parameters evaluated. Biodiversity changes in the sacred groves may be governed by biophysical drivers, while a combination of human and biophysical explained the variation in rotational fallow vegetation.  相似文献   

15.
Genomic resources such as single nucleotide polymorphism (SNPs), insertions and deletions (InDels) and SSRs (simple sequence repeats) are essential for crop improvement and better utilization in genetic breeding. However, the resources for the sacred lotus (Nelumbo nucifera Gaertn.) are still limited. In the present study, to dissect large-scale genomic molecular marker resources for sacred lotus, we re-sequenced a Thailand sacred lotus cultivar ‘Chiang Mai wild lotus’ and compared with the reported lotus genome ‘Middle lake wild lotus’. A total of 3,180,059 SNPs, 328, 251 InDels and 14,191 SVs were found between the two genomes. The functional impact analyses of these SNPs indicated that they may be involved in metabolic processes, binding, catalytic activity, etc. Mining the genome sequences for SSRs showed that 191,657 SSRs were identified with a frequency of one SSR per 4.23 kb and 103,656 SSR primer pairs were designed. Furthermore, 14, 502 EST-SSRs were also indentified using the available RNA-seq data in the NCBI. A subset of 150 SSRs (genomic and EST-SSRs) was randomly selected for validation and genetic diversity analysis. The genotypes could be easily distinguished using these SSR markers and the ‘Chiang Mai wild lotus’ was obviously differentiated from the other Chinese accessions. This study provides considerable amounts of genomic resources and markers for the quantitative trait locus (QTL) identification and molecular selection of the species, which could have a potential role in various applications in sacred lotus breeding.  相似文献   

16.
传统圈养和半自然散放环境亚成年大熊猫的行为差异   总被引:9,自引:0,他引:9  
2001年7月20日至8月20日,在四川卧龙自然保护区中国保护大熊猫研究中心,采用连续观察法记录和分析了传统圈养和半自然散放环境下亚成年大熊猫(分别为3和9只)的几种行为的持续时间和发生次数。传统圈养环境亚成年大熊猫探究行为的持续时间、标记行为的频次显著多于半自然散放环境下的个体;刻板行为的持续时间有增加的趋势,但无显著差异。刻板行为的持续时间与标记行为的频次和探究行为的持续时间均呈显著正相关。表明圈养环境的改善有助于亚成年大熊猫探究和标记行为的明显减少。  相似文献   

17.
We analyzed the effects of planktivorous Holeshestes heterodon Eigenmann (Characidae) predation on the plankton community of a small subtropical reservoir, using four enclosures (volume about 17.5 m3), open to the sediment, established in the littoral zone. Two enclosures were stocked with fish (mean TL 5.7 cm), at a density of about 4–5 fish m–3 (approx. 8 g m–3), whereas two remained fishless. The experiment lasted a little longer than one month. In the fish enclosures, most Crustacea and Chaoborus larvae remained scarce, probably as a result of visually selective fish predation. In both fishless enclosures, Chaoborus larvae became abundant. However, in only one of these did large individuals become relatively numerous; this discrepancy in the demographic structure of the Chaoborus populations between the two fishless enclosures is unexplained. Only in the fishless enclosure without appreciable numbers of large Chaoborus did densities of Crustacea increase greatly. It is suggested that in the enclosure containing large Chaoborus individuals, crustacean populations were prevented from developing due to predation pressure, while the small Chaoborus larvae of the other enclosure could not readily consume these prey. Rotifers were low in abundance in the absence of fish, probably as a consequence of Chaoborus predation. Phytoplankton density increased in all four enclosures, due probably to the lack of water flow. Only in the fishless enclosure with high densities of crustaceans did phytoplankton abundance decrease markedly at the end of the experiment, perhaps because of grazing losses.  相似文献   

18.
The objective of this study was to evaluate the effects of different captive housing conditions on reproductive cyclicity and adrenocortical activity in adult females of two small‐sized felid species, the tigrina (Leopardus tigrinus; n = 3) and margay (Leopardus wiedii; n = 2). Females were housed as singletons and subjected to three enclosure conditions over successive time periods: Phase I—large, enriched enclosures for 3 months; Phase II—small, empty enclosures for 5.5 months; Phase III—the same small enclosures enriched with branches and nest boxes for 6.5 months. Fecal samples were collected five times weekly throughout the study for analysis of progestagen, estrogen, and corticoid metabolites. On the basis of observed behaviors, stereotypic pacing was more frequent before feeding for all cats, regardless of enclosure conditions. Both species displayed a bimodal activity pattern, with peaks occurring at nightfall and dawn. All animals exhibited agitated behavior, characterized by a high frequency and duration of stereotypic pacing, primarily during the first 3 days after moving to the small empty enclosures. On the basis of hormonal analyses, ovarian follicular activity decreased and corticoid concentrations increased in tigrinas after transfer to the small barren cages compared to the patterns observed in the initial large, enriched enclosures. Corticoid concentrations in tigrinas then declined after small cage enrichment. Margay females exhibited increased corticoid excretion during Phases II and III, but in contrast to tigrinas, concentrations remained high even after cage enrichment. It was further showed that enriching the small enclosures was insufficient to reestablish normal ovarian activity within the time frame of the study for both species. In summary, margay and tigrina females exhibited distinct elevations in corticoid concentrations after transfer from large enriched enclosures to smaller barren cages that corresponded with agitated behavior, especially immediately after transfer. Fecal corticoid concentrations were reduced after cage enrichment in tigrinas, but not in margays. Although only a few individuals were evaluated, data suggest there may be species differences in response to captive environmental conditions. Overall results emphasize the importance of enclosure dimensions and enrichment when designing species appropriate environments for improving the health and reproductive fitness of threatened species. Zool Biol 26:441–460, 2007. © 2007 Wiley‐Liss, Inc.  相似文献   

19.
We conducted an experimental study to test the hypothesis that, at low female availability, males show intrasexual aggressive behaviour and home range owners are more aggressive than home range intruders. Using field dyadic arena test, we carried out 35 male–male trials in four 0.25 ha enclosures, two male-biased (experimental enclosures) and two unbiased (control enclosures). Dyadic encounters were conducted between unrelated and sexually mature males of similar weight and age which established home ranges in the same enclosure at the same trapping session. Each inter-male encounter was performed in the home range of one of the opponents between the home range owner and a home range intruder. When sex ratios were male-biased, inter-male amicable behaviour was absent and we found significant rates of inter-male aggressiveness, being home range owners much more aggressive than intruders. In the unbiased enclosures, inter-male encounters resulted mainly in noninteractive or amicable interactions. We found that inter-male aggression varied in relation to female availability being more evident in home range owners.  相似文献   

20.
Synopsis Effects of environmental factors on the distribution and abundance of yellow perch and central mudminnows in northern Wisconsin were examined by holding populations of these fishes within single-species enclosures in a series of three small forest lakes having a species-richness gradient of one to four species. These enclosures allowed each species to experience environmental conditions within each lake without directly interacting with each other. In the four-species lake, two other sets of enclosures addressed the effects of intra- and interspecific competition. Changes in total biomass of enclosure stocks (from growth and mortality) indicated that in the absence of other species, perch did best in the lake containing the richest fish assemblage, intermediate in the two-species lake, and worst in the mudminnow-only lake. Mudminnow stocks similarly performed significantly better in the four-species lake than the mudminnow-only lake. These results suggest that the lakes' environmental conditions contribute to the patterns of presence and abundance of perch, but that interspecific interactions override a similar contribution for the mudminnow, which is regarded as a fugitive species. Perch performances were also sensitive to fish densities within enclosures, declining significantly when stocks were doubled, either by adding more perch or equal numbers of mudminnows.  相似文献   

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