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1.
A group of woolly monkeys (Lagothrix lagothricha), studied for 1,800 hr from June 1984 until September 1987 in the eastern Colombian Amazon, used a home range of about 760 ha, 90% of which overlapped the ranges of three other groups. Home range use varied throughout the year, correlating in part with variations in fruit production. The home range exhibited a nonexclusive “core area” in the floristically most diverse part of the home range, although the majority of the home range was entered at a much lower frequency. Within the study area woolly monkeys occurred at a density of 5.5 individuals/km2. The average day range was 2,880 m, and the average straight line distance between sleeping sites was 896 m. Day ranges differed significantly across months, but the only significant correlation tested was a positive relation with time spent “moving” in the activity budget. Comparisons with three other Amazonian sites where woolly monkeys have been studied reveal considerable variation. Soil fertility, plant community differences, and other factors seem to influence ranging patterns. © 1996 Wiley-Liss, Inc.  相似文献   

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Monitoring adrenocortical activity in wild primate populations is critical, given the well‐documented relationship between stress, health, and reproduction. Although many primate studies have quantified fecal glucocorticoid metabolite (FGM) concentrations, it is imperative that researchers validate their method for each species. Here, we describe and validate a technique for field extraction and storage of FGMs in wild chimpanzees (Pan troglodytes). Our method circumvents many of the logistical challenges associated with field studies while yielding similar results to a commonly used laboratory method. We further validate that our method accurately reflects stress physiology using an adrenocorticotropic hormone challenge in a captive chimpanzee and an FGM peak at parturition in a wild subject. Finally, we quantify circadian patterns for FGMs for the first time in this species. Understanding these patterns may allow researchers to directly link specific events with the stress response. Am. J. Primatol. 75:57‐64, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   

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The brown hyaena (Hyaena brunnea) is the least known of the large predators of southern Africa. The current IUCN status of the brown hyaena is “Near Threatened”, and there are conservation concerns related to a general lack of biological knowledge of the species. For instance, a better knowledge of the responses to environmental and social stressors would improve our abilities to sustainably manage brown hyaena populations in both captive and free‐ranging environments. We conducted adrenocorticotrophic hormone (ACTH) challenges in one female and one male adult brown hyaena at Lion Park Zoo, South Africa, to validate measurements of glucocorticoid metabolites (GCM) in brown hyaena feces via an enzyme immunoassay (EIA). We also measured gastrointestinal transit times (GIT times) and the GCM degradation in feces left in ambient temperature for up to 32 hr to more reliably assess the use of this assay as a tool for non‐invasive glucocorticoid measurements. Intramuscular injections of synthetic ACTH yielded GCM levels of 388% (female) and 2,682% (male) above baseline with peak increases occurring 25‐ to 40‐hr after injection. The time delay of fecal GCM excretion approximately corresponded with food transit time in the brown hyaenas. Fecal GCM levels declined significantly over time since defecation. Our results provided a good validation that fecal GCMs accurately reflect circulating glucocorticoid stress hormones in brown hyaenas, but we highlight that samples have to be frozen immediately after defecation to avoid bias in the measurements as a result of bacterial degredation. Zoo Biol 30:451–458, 2011. © 2010 Wiley‐Liss, Inc.  相似文献   

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Short-term elevation of glucocorticoids (GCs) is one of the major physiological mechanisms by which vertebrates cope with challenging environmental or social factors (stressors). However, when exposure to stressors occurs repeatedly or over a prolonged period of time, animals may experience chronic elevation of GCs, which reduces the immune response efficiency and can lead to higher intensity of parasitic infection. Here, we used invasive gray squirrels Sciurus carolinensis introduced in Northern Italy and their 2 most prevalent gastrointestinal parasites, the nematode Strongyloides robustus and coccidia of the genus Eimeria, as a model to investigate relationships among macroparasite infection and concentrations of fecal glucocorticoid metabolites (FGMs), an integrated measure of circulating GCs. Our results revealed an association of FGMs with infection by St. robustus, but not with coccidia. Individuals with higher FGMs appear to be responsible for the greatest St. robustus egg shedding within gray squirrel populations, thus possibly acting as superspreaders. However, FGMs were negatively associated with adult St. robustus, suggesting that the abundance of adults of this nematode species does not induce elevation in FGMs, but is only affected by it through immune-mediated effects on its fecundity. Finally, the relationship between St. robustus (both eggs and adult parasites) and FGMs was not linear, suggesting that only high levels of physiological stress influence parasite infection. Our findings highlight that the direction and magnitude of the stress–infection relationship may depend not only on the specific host–parasite system, but also on the different life stages of the same parasite.  相似文献   

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Spider monkey communities are classic fission-fusion primate societies. I present data suggesting that spider monkeys (Ateles chamek) at Lago Caiman are territorial; adult males traveled further and faster than adult females and subgroup size was significantly higher in boundary areas of the spider monkey territory where intercommunity disputes were observed than in non-boundary areas. I then go on to examine data from 20 Ateles communities distributed across 14 study sites and five species to investigate how a series of demographic, ecological and geographical parameters influence the number of males in a given spider monkey community. Analyses suggest that the number of males is not significantly related to the number of females in a community, the area of the community home range, or the total perimeter length of the community boundary. However, risky boundary perimeter length, or the length of perimeter that directly borders another spider monkey community, explains 88% of observed variations in the number of males in each community. I discuss the results in relation to spider monkey ecology and territoriality, as well as the potential of this relationship for explaining chimpanzee (Pan) behavior given their extremely similar fruit specialist, male philopatry, territoriality and fission-fusion social system.  相似文献   

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圈养大熊猫野化培训期的生境选择特征   总被引:1,自引:0,他引:1       下载免费PDF全文
大熊猫(Ailuropoda melanoleuca)是我国特有的珍稀物种,也是世界上最濒危的野生动物之一。为了将人工繁育的部分大熊猫个体重引入其历史分布区或复壮野生种群,中国保护大熊猫研究中心从2003年开始进行圈养大熊猫的野外放归工作,通过野化培训以提高圈养大熊猫适应和选择野外环境的能力。对野化培训大熊猫\"淘淘\"的生境选择研究表明:该野化培训大熊猫幼仔经常活动于新笋密度较大的区域[生境与对照:(2.68±1.14)对(1.58±0.66)],却避开成竹密度过大[(9.91±2.51)对(12.18±4.68)]、竹子较高[(4.57±1.09) m对(4.98±0.66) m]以及枯死竹过多[(2.52±0.86)对(3.39±1.33)]的区域;喜欢活动于离水源[(1.59±0.67)对(2.19±0.87)]和隐蔽场所较近[(5.37±2.14) m对(8.35±7.76)m],以及距离乔木较远[(3.09±0.69) m对(2.70±0.42) m]和郁闭度较低[(1.85±0.57)对(2.10±0.47)]的区域(P < 0.05),新笋密度大小是该栖息地在整个野化培训期间是否被利用的最重要因素。该野化培训大熊猫幼仔保持着与带仔母兽相近的生境选择特征,对竹子环境的选择也与卧龙野生大熊猫相似,野化培训对该大熊猫幼仔产生了积极的作用。野化培训大熊猫幼仔形成的家域和核域面积分别为9.21 hm2 和1.93 hm2,占野化培训圈面积的51.95%和10.89%,其中家域面积仅有卧龙野生大熊猫的1.4%-2.4%,所以在以后的野化培训过程中需要采取增加野化培训圈中环境丰富度等方式,促进野化培训大熊猫形成较大的家域面积。  相似文献   

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Jaguars are threatened with extinction throughout their range. A sustainable captive population can serve as a hedge against extinction, but only if they are healthy and reproduce. Understanding how jaguars respond to stressors may help improve the captive environment and enhance their wellbeing. Thus, our objectives were to: (1) conduct an adrenocorticotrophic hormone (ACTH) challenge to validate a cortisol radioimmunoassay (RIA) for noninvasive monitoring of adrenocortical function in jaguars; (2) investigate the relationship between fecal corticoid (FCM) and androgen metabolite (FAM) concentrations in males during the ACTH challenge; and (3) establish a range of physiological concentrations of FCMs for the proposed protocol. Seven jaguars (3 M, 4 F) received 500 IU/animal of ACTH. Pre‐ and post‐ACTH fecal samples were assayed for corticoid (M and F) and androgen metabolites (M) by RIA. Concentrations of FCMs increased (P80.01) after ACTH injection (pre‐ACTH: 0.90 ± 0.12 µg/g dry feces; post‐ACTH: 2.55 ± 0.25 µg/g). Considering pre‐ and post‐ACTH samples, FCM concentrations were higher (P80.01) in males (2.15 ± 0.20 µg/g) than in females (1.30 ± 0.20 µg/g), but the magnitude of the response to ACTH was comparable (P>0.05) between genders. After ACTH injection, FAMs increased in two (of 3) males; in one male, FCMs and FAMs were positively correlated (0.60; P80.01). Excretion of FCMs was assessed in 16 jaguars (7 M, 9 F) and found to be highly variable (range, 80.11–1.56 µg/g). In conclusion, this study presents a cortisol RIA for monitoring adrenocortical function in jaguars noninvasively. Zoo Biol 31:426–441, 2012. © 2011 Wiley Periodicals, Inc.  相似文献   

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  总被引:1,自引:0,他引:1  
The first telemetry study analysing behaviour of the largest freshwater predator in European rivers, Silurus glanis , was performed bimonthly during the years 2002–2004. Movement of juveniles and adults occurred mostly in the same time intervals. The only statistical differences occurred for nocturnal activity in spring and autumn. In spring and winter, activity was low with the peaks during daylight, and in autumn, maximal movement was recorded during dusk. In summer, the European catfish were active across the whole 24 h even during high-flow conditions. During all other seasons, movement was inversely related to flow rate. Maximal home ranges occurred in summer, being larger for adults. Juveniles and adults were spatially segregated. With increasing flow, fish were displaced, and individuals from both groups got closer to each other. Only juveniles migrated downstream from the upstream isolated river stretch suggesting a negative impact of lateral obstructions on the fish population structure.  相似文献   

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Non‐invasive techniques for monitoring the stress response in captive western lowland gorillas (Gorilla gorilla gorilla) were investigated. Fecal samples for cortisol measurement and concurrent behavioral data were collected from six individuals in a socially housed gorilla group (one adult male, three adult females and their three offspring) over a 7‐month period. Despite inter‐individual variation in the dynamics of fecal cortisol concentrations over time, several major secretory peaks coincided across individuals. High cortisol concentrations in feces were correlated with induced stressors or behavioral observations indicating high social tension, with a 1–2 day lag period. Entry progression order of the gorillas into a den complex and a supplant‐based dominance index were suitable indicators of overall dominance hierarchies, and fluctuations over time reflected periods of instability. Diurnal variation in fecal cortisol was not apparent when comparing afternoon and morning samples, however the sample collection interval was relatively short (3–5 hr). These results demonstrate the feasibility of monitoring stress responses based on the dynamics of both fecal cortisol excretion and behavior. This non‐invasive approach may be used for gauging responses to changes in husbandry, environment and group structure of captive gorillas. Zoo Biol 0:1–15, 2005. © 2005 Wiley‐Liss, Inc.  相似文献   

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A better understanding of the factors regulating feed efficiency and their potential as predictors of feed efficiency in cattle is needed. Therefore, the potential of three classes of traits, namely, feeding behavior characteristics: daily time at feeder (TF; min/day), time per meal (TM; min), meal size (MS; g DM), eating rate (ER; g DM/min), number of daily meals (NM) and daily visits to the feeder (VF); infrared (IR) thermography traits (°C): eye (EY), cheek (CK), snout (SN), ribs (RB) and hind area (HA); and glucocorticoid levels: fecal cortisol metabolites (FCM; ng/g) and plasma cortisol (PC; ng/ml) as predictors of efficiency were evaluated in 91 steers (436 ± 37 kg) over 2 years (Y1 = 46; Y2 = 45). Additionally, the individual traits of each of these three classes were combined to define three single traits. Individual daily feed intake of a corn silage and high-moisture corn-based diet was measured using an automated feeding system. Body weight and thermographs were taken every 28 days over a period of 140 days. Four productive performance traits were calculated: daily dry matter intake (DMI), average daily gain (ADG), feed to gain ratio (F : G) and residual feed intake (RFI). Steers were also classified into three RFI categories (low-, medium- and high-RFI). Among the feeding behavior characteristics, MS and ER were correlated with all efficiency traits (range: 0.26 to 0.75). Low-RFI (more efficient steers) had smaller MS, lower ER and fewer VF in comparison to high-RFI steers. Less efficient steers (high-RFI) performed more VF during the nocturnal period than more efficient steers. More efficient steers had lower CK and SN temperatures than less efficient steers (28.1°C v. 29.2°C and 30.0°C v. 31.2°C), indicating greater energetic efficiency for low-RFI steers. In terms of glucocorticoids, PC was not correlated with efficiency traits. In contrast, more efficient steers had higher FCM in comparison to less efficient steers (51.1 v. 31.2 ng/g), indicating that a higher cortisol baseline is related to better feed efficiency. The overall evaluation of the three classes of traits revealed that feeding behavior, IR thermography and glucocorticoids accounted for 18%, 59% and 7% of the total variation associated with RFI, respectively. These classes of traits have usefulness in the indirect assessment of feed efficiency in cattle. Among them, IR thermography was the most promising alternative to screen cattle for this feed efficiency. These findings might have application in selection programs and in the better understanding of the biological basis associated with productive performance.  相似文献   

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ABSTRACT The kernel density estimator is used commonly for estimating animal utilization distributions from location data. This technique requires estimation of a bandwidth, for which ecologists often use least-squares cross-validation (LSCV). However, LSCV has large variance and a tendency to under-smooth data, and it fails to generate a bandwidth estimate in some situations. We compared performance of 2 new bandwidth estimators (root-n) versus that of LSCV using simulated data and location data from sharp-shinned hawks (Accipter striatus) and red wolves (Canis rufus). With simulated data containing no repeat locations, LSCV often produced a better fit between estimated and true utilization distributions than did root-n estimators on a case-by-case basis. On average, LSCV also provided lower positive relative error in home-range areas with small sample sizes of simulated data. However, root-n estimators tended to produce a better fit than LSCV on average because of extremely poor estimates generated on occasion by LSCV. Furthermore, the relative performance of LSCV decreased substantially as the number of repeat locations in the data increased. Root-n estimators also generally provided a better fit between utilization distributions generated from subsamples of hawk data and the local densities of locations from the full data sets. Least-squares cross-validation generated more unrealistically disjointed estimates of home ranges using real location data from red wolf packs. Most importantly, LSCV failed to generate home-range estimates for >20% of red wolf packs due to presence of repeat locations. We conclude that root-n estimators are superior to LSCV for larger data sets with repeat locations or other extreme clumping of data. In contrast, LSCV may be superior where the primary interest is in generating animal home ranges (rather than the utilization distribution) and data sets are small with limited clumping of locations.  相似文献   

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Mycophagy has been documented in a number of species of marmosets and lion tamarins (Callitrichinae) but its effect on ranging behavior is not known. We present the results of 10 years of research on five groups of Goeldi's monkey (Callimico goeldii) at a field site in northwestern Bolivia. We studied the diet and ranging behavior of two of the groups. On average, groups contained 4.5 individuals (range 2.0–9.0), but they gradually decreased in size until only the breeding female remained in the home range. The annual diet was composed of fungi (31.1–34.9%), fruits (34.0–40.6%), prey (17.4–30.1%), and exudates (1.0–10.9%). They had large home ranges (114–150 ha) and over time individuals tended to shift their core areas of use. They used secondary and bamboo forest and forest with dense understories more than expected based on availability. We suggest that the large home ranges and shifting core areas used by C. goeldii are components of a foraging strategy to track patchy, low density, and ephemeral fungal fruiting bodies. Our results, along with data published on other callitrichines, indicate that groups of Leontopithecus, Callithrix, and Callimico that eat fungi have larger home ranges than those that do not. Mycophagy is one of the several factors that evidently affect home range size in callitrichines. Fungi are clearly an important food source for a number of populations, but additional studies are needed to determine why some eat fungi frequently while others do not. Am J Phys Anthropol, 2010. © 2010 Wiley‐Liss, Inc.  相似文献   

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Conservation strategies for crocodilians often include captive breeding to create stable assurance populations. Evaluating adrenal and gonadal hormone patterns can provide animal managers with data to more effectively monitor animal welfare and reproductive status. This study evaluated the effects of season (breeding, nesting, or off), sex (male and female), and reproductive status of females (egg-laying/housed with a male or non-laying/housed solo) on concentrations of fecal glucocorticoid metabolite (FGM), fecal androgen metabolite (FAM), and fecal progestogen metabolite (FPM) in seven Cuban crocodiles, Crocodylus rhombifer, at the Smithsonian's National Zoological Park. Overall, seasonal changes in FGM and FPM concentrations were only observed in egg-laying females; FGM and FPM concentrations were both higher during the nesting season compared to the breeding and off seasons. Seasonal changes in FAM concentrations were only observed in males; males had higher FAM concentrations during the breeding and nesting seasons compared to the off season. Future studies investigating the use of fecal hormone metabolites in crocodilians are necessary to understand differences between individuals and species, to further elucidate the interactions between hormones and environmental factors, such as social housing, and to develop long-term datasets for the management of this species.  相似文献   

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Monitoring adrenal activity through noninvasive fecal hormone sampling is rapidly gaining popularity as a tool to assess zoo animal welfare. However, few studies have sought to investigate the interrelationships between behavior, adrenal activity, and environment, and ask whether both behavioral and adrenal monitoring strategies are required to assess welfare sufficiently. We present the findings of a 9-month study of a small group (one male, two females) of Western lowland gorillas, Gorilla gorilla gorilla. First, we examined the effect of environmental variables on gorilla behavior. Second, we examined the effect of environmental variables on the concentration of fecal glucocorticoid metabolites (FGC) and the relationship between behavior and FGC. Environmental variables had similar effects on all three gorillas. Negative vigilance of visitors (NVV; staring, posturing, and charging at visitors) significantly increased in all subjects as environmental noise levels increased, and food-related behavior significantly decreased in all subjects as crowd size increased. Exhibit modifications had a number of positive effects on behavior. Notably, when privacy screens were used, NVV significantly decreased in two subjects. We found no significant effects of environmental variables on FGC. However, we did find significant relationships between behavior and FGC in one female. Specifically, her NVV was significantly higher one day before, and on the same day as, raised FGC. Also, hair plucking significantly increased in the two days following raised FGC. Overall, this study demonstrates how concurrent noninvasive fecal and behavioral monitoring can be used for gorilla welfare assessment.  相似文献   

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ABSTRACT.   We present the first report of population density and home range estimates for the Chestnut Wood-quail ( Odontophorus hyperythrus ), an endemic and nearly threatened species of the Colombian Andes. Density estimates were obtained using playbacks and spot mapping and point transect methods. Home range sizes were estimated by radio tracking five wood-quail. Estimated densities varied from 0.3 to 0.4 groups per hectare. These densities are similar to those reported for other mountain wood-quail, but higher than those for lowland wood-quail and other species in the family Odontophoridae. Estimates of home range size varied from 2.6 to 9.0 hectares per group, and seemed to be correlated with group size. We also found evidence of overlap in the home ranges of neighboring groups. Population densities may vary with factors such as habitat type, but our estimates allow a first approximation of the population sizes of Chestnut Wood-quail in forest fragments.  相似文献   

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ABSTRACT Fecal corticosterone metabolites are commonly used in avian ecology as a measure of response to stress. Recent research on mammals suggested that the manner in which samples are stored could be critical to alleviating any storage handling bias. Cross-reacting metabolites can increase glucocorticoid metabolites even after samples are frozen and, thus, result in an overestimation of hormone levels as the time increases between when samples were collected and when levels are measured. We examined effects of sample storage time on fecal corticosterone metabolites for 2 avian species across 165 days. We observed no change in fecal corticosterone metabolites across the sampling periods in either fulvous whistling-ducks (Dendrocygna bicolor) or white ibis (Eudocimus albus). Results suggest that avian fecal corticosterone metabolite levels do not change when samples are frozen for long periods of time and that there were no differences in the response between the 2 species we compared. This study demonstrated that avian fecal corticosterone samples are accurate even after freezing and, thus, studies that seek to address conservation questions may rely on these data. Studies of additional bird species are needed to generalize our findings to other avian taxa.  相似文献   

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