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1.
Janis Gonzlez-Martínez 《American journal of primatology》1998,45(4):351-365
This paper presents the results of a study on the introduced, free-ranging patas monkey population of Southwestern Puerto Rico (SWPR). It describes information on the population size, social group composition, diet, daily ranging patterns, and patas home range during a 3 year period. The patas monkey population in the study area consisted of approximately 120 individuals in four heterosexual groups and several all-male bands. Within their home ranges (26.8 km2), the population density was 4.47 individuals/km2. Home range size among the population's four heterosexual groups varied from 3.72 km2 to 15.39 km2, and minimum daily distance traveled ranged from 0.8–2.0 km. In general, the social structure and mating system of this population parallels what has been described for African populations. However, habitat use, ranging behavior, and the quality of intergroup interactions suggests that patas of this population exhibit territorial behavior. Am. J. Primatol. 45:351–365, 1998. © 1998 Wiley-Liss, Inc. 相似文献
2.
Oliver Krüger Edda Affeldt Marian Brackmann Kirsten Milhahn 《International journal of primatology》1998,19(2):287-297
We documented and assessed the influence of chimpanzee activity on group size and composition of Colobus guereza in Kyambura Gorge, southwest Uganda, from July to September, 1994 and in February and March 1996. The population density of colobus is very high: 347 individuals per km
2. Density differed outside activity centers of chimpanzees (525 individuals per km
2
) and within the centers (186 per km
2
). We identified a total of 24 colobus groups, ranging between 3 and 13 individuals. Of the 24 groups, 22 were one-male groups. Groups were smaller and the percentage of subadults and juveniles was lower in groups within chimpanzee activity centers. Estimates of home ranges are between 1.7 and 6.2 ha, but neighboring home ranges overlapped 80%. Only a territory of approximately 0.5 ha was defended by the alpha male. 相似文献
3.
JENNIFER H. VASHON AMY L. MEEHAN WALTER J. JAKUBAS JOHN F. ORGAN ADAM D. VASHON CRAIG R. MCLAUGHLIN GEORGE J. MATULA JR. SHANNON M. CROWLEY 《The Journal of wildlife management》2008,72(7):1479-1487
Abstract Canada lynx (Lynx canadensis) were listed as a federally threatened species in 14 states at the southern extent of their geographic range in March 2000, with Maine being the only state in the northeastern United States known to support a resident population. Relatively little information is known about the ecology of lynx living at the southern edge of their range, including range requirements, movements, and spatial organization. Basic knowledge of lynx ecology is needed for federal recovery planning efforts. Between 1999 and 2004, we trapped and radiocollared 43 lynx (21 M, 22 F) in northern Maine in an intensively managed and predominantly early successional forested landscape. We estimated diurnal annual and seasonal home-range size for male and female lynx using the 85% fixed-kernel home-range estimator. Annual home ranges of adult male lynx (x̄ = 53.6 km2) were more than twice the size of adult female home ranges (x̄ = 25.7 km2). Home ranges of adult females during snow periods (x̄ = 38.3 km2) were nearly 3 times larger than their snow-free-period ranges (x̄ = 14.3 km2), whereas, snow-free ranges of adult males (x̄ = 58.8 km2) were slightly larger than their snow-period ranges (x̄ = 45.2 km2). We observed a limited amount of home-range overlap among lynx of the same sex (F: x̄ = 17.2%; M: x̄ = 11.8%). Lynx of opposite sex showed more extensive overlap (x̄ = 24.3%). Most home-range shifts of resident lynx were typically not extensive. Based on territory mapping, we estimated a minimum lynx density of 9.2–13.0 lynx/100 km2. We observed lynx spatial ecology and densities that were more similar to northern lynx populations when hares were abundant than to other southern lynx populations, suggesting that region-specific studies under varying habitat conditions and hare densities are needed to ensure realistic recovery goals and effective management of lynx at the southern extent of their range. 相似文献
4.
I. V. Seryodkin J. Paczkowski M. Y. Borisov Y. K. Petrunenko 《Contemporary Problems of Ecology》2017,10(6):599-611
Territorial activity was studied using satellite tracking of four brown bears (Ursus arctos) in Kamchatka in 2005–2006 and three brown bears on Sakhalin in 2011–2012. The size of annual home ranges was 6.09–27.58 km2 for females and 153.12 km2 for males. The size of the nuclear zone of the annual home ranges did not exceed 1.68 km2. Seasonal home ranges were largest in August-September and smallest in May. The home ranges of two females in Kamchatka were significantly overlapped, the lesser degree of overlap was noted for two females on Sakhalin. The nature of the use of the study area by bears, essentially depends on the seasonal distribution of food, in particular salmon. 相似文献
5.
Evan R. Buechley Michael J. McGrady Emrah Çoban Çağan H. Şekercioğlu 《Biodiversity and Conservation》2018,27(9):2293-2310
Vultures comprise the most endangered avian foraging guild (obligate scavengers) and their loss from ecosystems can trigger trophic cascades, mesopredator release, and human rabies epidemics, indicating their keystone species status. Vultures’ extremely large home ranges, which often cross international borders of countries that have differing laws and capacity for wildlife conservation, makes conserving them challenging. However, satellite-tracking data can be used to identify habitat preferences and critical sites to target conservation actions. We tracked 16 Egyptian Vultures, Neophron percnopterus, in the Middle East and East Africa. We used dynamic Brownian bridge movement models to calculate home ranges and core-use areas, and we analyzed habitat use in a resource selection framework. Combined summer and winter ranges (99% utilization distributions) of all birds covered 209,800 and 274,300 km2, respectively. However, the core-use areas (50% utilization distributions) in the summer and winter ranges, accounted for only 0.4–1.1% of this area (900 and 3100 km2, respectively). These core-use areas are where the home ranges of multiple individuals overlapped and/or where individuals spent a lot of time, such as feeding and roosting sites, and are places where conservation actions could focus. Resource selection models predicted Egyptian Vulture occurrence throughout little-studied parts of the species’ range in the Middle East and East Africa, and revealed strong selection for proximity to highways, power distribution lines, and towns. While providing roosts (e.g. power pylons) and food (e.g. garbage dumps), anthropogenic features may also function as ecological traps by increasing exposure to electrocution and dietary toxins. 相似文献
6.
C. J. BROWN 《Ostrich》2013,84(1-2):43-49
Brown, C. J. 1990. Breeding biology of the Bearded Vulture in southern Africa, Part III: The post-nestling dependence period. Ostrich 6l: 43–49. The post-nestling dependence period of the Bearded Vulture Gypaetus barbatus in southern Africa begins with the first flight of the young bird at 126 ± 2 days after latching (November-January) and ends during the pre-laying nod or the parent birds' next breeding attempt (April-June), a nod of about five months. For the first two weeks after first flit young bid remaine6 within about 200m of the nest, moving up to 800 m by the third week. By a month out of the nest young birds spent about 40% of the day in flight, moved up to 3 km from the nest, began bone-dropping and interacting with young birds from neighbouring nests. At six weeks they began to accompany their parents for part of some of their foraging trips, but returned to the nest alone, and by eight weeks they completed foraging forays with parents Pasting up to 3 h. At 2–3 months out of the nest young birds covered an area of about 42 km2, excluding the foraging trips with parents, by 3–4 months, 78km2 and 4–6 months, 168 km2. Parent birds delivered food for at least five months after the young bird's first flight. Young birds left their natal areas of their own accord, usually during the first month of their parents' next breeding attempt. 相似文献
7.
The lack of long-term studies remains a limiting factor in understanding the home range, spatial ecology and movement of giraffes. We equipped eight giraffes with GPS satellite units and VHF capacity, which were built in to the collars for the remote collection of data on their movements and home ranges over two years on Khamab Kalahari Nature Reserve (KKNR) within the Kalahari region of South Africa. Giraffe numbers in KKNR dropped from 135 individuals to 111 in just five years, revealing the lack of knowledge about their required habitat needs, space use and diet. With over 1000 km2 available for roaming within the reserve, habitat selection, principle and preferred food species played a significant role in home range size and overlap between individuals. These giraffes used an average annual home range of 206 km2 (20 602 ha) as calculated by a 95% minimum convex polygon (MCP) with a standard deviation core home range calculated by a 50% MCP of 10.1 km2 to satisfy their annual needs for survival and reproduction in their preferred vegetation. In the wet, hot season (summer: December–February) when food was abundant, giraffes frequented smaller areas (average 177 km2), while in the dry, cool season (winter: June to August) the mean home range size increased to approximately 245 km2. Rainfall influenced spatial distribution since it determined vegetation productivity and leaf phenology. The different seasons influenced giraffe movements, while different vegetation types and season influenced their home range size. Season and food availability also influenced home range overlap between different giraffe herds. Home range overlap occurred when giraffes were forced to roam in overlapping areas during the dryer months when the winter deciduous nature of the majority of the tree species resulted in lower food availability. In winter, the overlap was approximately 31% and in autumn approximately 23%. During the wet and warmer months, overlapping was 15% in summer and 19% in spring, respectively. The percentage of time spent in different vegetation type areas was influenced by the abundance of the principal food species of that plant community. It is thus concluded that the movements of giraffes were primarily influenced by a combination of environmental factors such as season, rainfall and vegetation density. 相似文献
8.
Between December 1974 and November 1975 (157 days), it was found that seasonal home range changes in the Shiga C troop were
closely related to food changes, vegetation, and the existence of neighbouring troops. The detailed points clarified may be
summarized as follows: (1) The seasonal home range sizes from winter to autumn were 1.23 km2, 1.46 km2, 1.69 km2, and 1.21 km2, respectively, and the annual size was 3.66 km2; (2) The food changed from bark and buds of trees in winter to young leaves and stems of grasses and trees in spring and
summer, and fruits in autumn; (3) Each home range clearly changed according to the phenology of the plants used as food at
each season; (4) The food abundance for the monkeys was extremely poor in winter, relatively poor in summer, plentiful in
spring, and the best in autumn; and (5) The Shiga C troop and the neighbouring Shiga B2 troop overlap in their home ranges in spring and autumn, but are separated during winter and summer. 相似文献
9.
Jeffrey A. Kurland 《Primates; journal of primatology》1973,14(2-3):245-262
Preliminary findings of a two-month pilot study of kra macaques (Macaca fascicularis
Raffles, 1821) at the Kutai Reserve in Kalimantan Timur, Indonesia, are reported. Kra macaques spend most of their time in the forest canopy, though they may be seen in the morning and afternoon on the riverbanks. The sexually dimorphic kra exist in multi-male groups averaging about 18 individuals. There is about one group per km2 of primary rainforest. Along the Sengata River, there were 2–5 groups per km2, or 36–90 macaques per km2 of riverine secondary forest. A home range for the primary study group was estimated to be about 0.8 km2. The daily range of this group varied from 0.4 to 1 km.Kra macaque groups partition into subgroups when sleeping and foraging. Agonism between foraging subgroups was common. Predation, except from humans, appears minimal. Frequent associations and interactions between kra macaques, birds, and other mammals is described. It may be that birds or the kra are using the other to locate clumped scarce food resources. Grooming, copulation, play, interactions with the observer, and male protective displays are briefly described. Observation conditions were difficult and hence only a small number of social interactions were observed. 相似文献
10.
During 1990–1992, a survey of the golden lion tamarin, Leontopithecus rosalia, was carried out throughout its known distribution area. Forest remnants were identified by visual interpretation of Landsat‐TM satellite images. Localities occupied by L. rosalia were first identified by interviews with local people. All forests more than 20 ha in size, and for which two or more interviews suggested the presence of the species, were surveyed using “play‐back” recordings of lion tamarin long calls. The total wild population of L. rosalia, including that of the Poço das Antas Biological Reserve, was estimated to be 562 individuals in 109 groups. The lion tamarins were generally found in four major areas of forest (six or more groups per forest, not including Poço das Antas), with a further 12 groups isolated in small forest patches. Currently the species' distribution is restricted to just four municipalities in the state of Rio de Janeiro: Silva Jardim, Cabo Frio, Saquarema, and Araruama. Although they are typically confined to lowland forest of <300 m altitude, L. rosalia was recorded at an altitude of 550 m in one locality. Average group size varied from 3.6 to 5.7 individuals, and densities from 0.39 groups/km2 to 2.35 groups/km2 (2.17 individuals/ km2 to 8.53 individuals/km2). Six of the isolated groups found during the survey were successfully translocated to a forest of 2,400 ha. There is now also a significant population of reintroduced lion tamarins. Overall, however, the possibilities for further expansion of the wild population are severely limited. Am. J. Primatol. 59:29–44, 2003. © 2003 Wiley‐Liss, Inc. 相似文献
11.
The investigation was carried out at two sampling areas in Lake Balaton (surface area 600 km2), of which one was hypertrophic and the other was mesotrophic. Species diversity was higher in the hypertrophic area, primarily due to a higher number of Anatid species. Contents of crops, gizzards, and intestines were analysed in 321 of the 361 birds collected. Diet was similar in certain species (Aythya fuligula, A. f. ferina, Anas querquedula) despite differences in the trophic state of their habitats. However, in other species (Anas p. platyrhyncha, Aythya nyroca, Bucephala c. clangula), percentage distribution of food items more or less reflected the food resources of the two areas in the digestive tracts. I concluded that the former species are highly selective in their feeding. 相似文献
12.
We studied factors affecting density and spacing patterns in the pine marten Martes martes population inhabiting temperate forests of Bia?owieza National Park, eastern Poland. From 1985/1986 to 1995/1996 marten densities ranged from 3.63 to 7.57 individuals 10 km?2 (mean 5.4) and were positively correlated with abundance of forest rodents in the previous year. The rate of marten population growth was inversely density‐dependent and positively related to rodent density. Annual mortality rate averaged 0.384 and tended to be negatively related to marten densities. Mean annual home range of males (2.58 km2, SE=0.24) was larger than that of females (1.41 km2, SE=0.20). Seasonal home ranges also differed significantly between males and females. Both sexes held the smallest ranges in December–January. Female ranges increased in April–May, whereas those of males increased in June–September when they were mating. Fidelity of pine martens to their home ranges was very high. The mean shift between arithmetic centres of seasonal ranges was 0.25 km, and the ranges recorded in two consecutive seasons overlapped, on average, by 87–90%. We observed very little home range overlap between neighbouring male (mean 4–6%) or female (mean 6%) marten. Year round the neighbouring individuals of the same sex neither avoided nor attracted each other. Females attracted males only during the spring‐summer mating season. A review of other studies has documented that winter severity and seasonal variation in ecosystem productivity were essential factors shaping the biogeographic variation in pine marten densities between 41o and 68oN. The density of marten populations increased in areas with mild winters and lower seasonality. Maximum population densities (indicative of habitat carrying capacity) were correlated with mean winter temperature. In Europe, male home ranges increased with decreasing forest cover in a study area, whereas female ranges varied positively with rodent abundance. 相似文献
13.
红隼(Falco tinnunculus)被列为国家二级重点保护野生动物,是能同时适应农村和城市环境的小型猛禽,对维持城市生态系统稳定具有重要意义。2022年4月至7月,为在北京救助的7只红隼佩戴了卫星追踪器,追踪其活动轨迹,依据追踪的动物活动位点数据,采用净平方位移-时间曲线依次对各红隼的迁徙模式进行了判别,深入分析了迁徙红隼的迁徙时间、距离和路线等,并采用核心密度法分别计算了迁徙及留居型红隼95%及50%活动区面积。研究结果表明,在北京地区红隼的迁徙模式为部分迁徙,追踪的7只红隼个体(N01 ~ N07)中,4只为留鸟,1只为迁徙鸟,2只居留类型无法准确判断。N01为迁徙红隼,其度夏地和越冬地分别在内蒙古锡林郭勒盟和河北廊坊,此红隼秋季迁徙速度明显高于春季,其春季迁徙距离551 km,历时25 d,平均迁徙速度为22 km/d,而秋季迁徙距离412 km,历时2 d,平均迁徙速度为203 km/d,河北承德滦平县是其春季迁徙的重要中途停歇地。不同红隼个体间95%及50%活动区面积均存在较大差异,迁徙红隼N01 95%、50%活动区面积在度夏区分别为93.10 km2、17.50 km2,在越冬区分别为7.03 km2、0.99 km2;留居型红隼95%、50%活动区面积均值分别为1 165.34 km2、178.71 km2(n = 4),其中最大95%、50%活动区面积分别为4 320.26 km2(N02)、648.22 km2(N02),最小95%、50%活动区面积分别为2.80 km2(N03)、0.29 km2(N03)。本研究揭示了北京地区红隼的迁徙模式、迁徙路线、重要停歇地及活动区状况,为红隼的针对性保护和管理提供了科学依据。 相似文献
14.
Resource dispersion and badger population density in Mediterranean woodlands: is food,water or geology the limiting factor? 总被引:5,自引:0,他引:5
Eurasian badgers, Meles meles, in Mediterranean cork‐oak woodlands live in small groups within territories that embrace a mosaic of habitats where several setts (dens) are scattered. Assuming that their population density was related to home range sizes and that this in turn was influenced by food and water availability and the existence of substrate suitable for sett construction, we explored the relationship between these parameters. Two biotopes were predominantly important in providing food security to badgers in the ‘Grândola’ mountain study area: olive groves and orchards or vegetable gardens. Analysis of the mean total area of these two habitats in the ranges of radio‐tracked badgers permitted us to extrapolate to an estimate that the 66 km2 encompassed eleven areas with the capacity to support badger groups each composed by 6–8 individuals. Since only three groups populated the area we concluded that food availability was not limiting badger density. Sites with surface water in summer (the dry season) seem sufficient to support more badger groups than existed, leading us to believe that this factor was also not limiting badger density. Simultaneously, using a logistic regression model and the biophysical characteristics of sett sites as explanatory variables, four predictor variables determined sett location: the existence of a geological fault/discontinuity, ridges, valleys and the distance to abandoned farm houses, of which the former had the higher odds ratio, being thus the best sett location predictor. Indeed, 56% of the areas predicted with >80% confidence to contain a badger sett were encompassed within a known home range. Therefore, our results suggest that, in Mediterranean cork oak woodlands in SW Portugal, the main factor limiting badger's density is the availability of suitable sites for setts. However, in areas where suitable sites for burrows existed, but food patches were absent, badgers were not found. This could indicate that the presence of both factors was necessary for badgers, although in this area sites suitable for digging setts appeared to be the primary limiting factor. 相似文献
15.
Bearded Vulture Gypaetus barbatus movements were investigated in southern Africa to determine whether an individual''s age, sex or breeding status influenced its ranging behaviour and to provide the information required to guide conservation activities. Data from satellite transmitters fitted to 18 individuals of four age classes were used to determine range size and use. Because of the nature of the movements of marked individuals, these data could be used to determine the overall foraging range of the entire population, which was estimated to be 51 767 km2. Although juvenile, immature and sub-adult birds used different parts of the overall range, their combined foraging range was 65% (33 636 km2) of the overall range. Average adult home ranges (286 km2) were only around 1% the size of the average foraging ranges of non-adults (10 540 –25 985 km2), with those of breeding adults being even smaller (95 km2). Home ranges of breeding adults did not vary in size between seasons but adults utilized their home range more intensively whilst breeding, moving greater distances during the incubation and chick hatching period. Range size and use increased as non-adults aged. Immatures and sub-adults had larger range sizes during winter, but range use of non-adults did not vary seasonally. Range size and use did not differ between the sexes in any of the age classes. Information on home range size and use enables specific areas within the species'' range to be targeted for management planning, education and conservation action. 相似文献
16.
T.M. Caro 《Animal behaviour》1976,24(4):889-897
Two lone silverback mountain gorillas (Gorilla gorilla beringei) were followed during a 13-week study period in an attempt to describe the size and differential use of their respective home ranges. The ranging behaviour was compared to that of groups and possible causes of daily movement were examined. The daily activity of one individual is described. Considerable differences between silverbacks were found not only in the time spent within areas of their ranges but in the ways they ranged over their core areas. The subject that had left his parent group earlier covered his core area more vigorously, by means of circuitous routing. Lone silverback ranges overlapped their parent group ranges considerably and the group frequently entered the silverback's core area. Lone males did not move further nor more rapidly than groups. Feeding, social interactions, and location of nest sites were examined to reveal the possible causes of daily ranging behaviour and it was tentatively concluded that availability of food supply regulated the silverback's movements. 相似文献
17.
STEPHANIE A. TUCKER WILLIAM R. CLARK TODD E. GOSSELINK 《The Journal of wildlife management》2008,72(5):1114-1124
Abstract: Historically, bobcats (Lynx rufus) were found throughout the Corn Belt region, but they nearly disappeared from this area due to habitat loss and unregulated harvest that occurred during the century after European settlement. Reports of bobcat occurrences have been increasing in Iowa, USA, and biologists would like to understand the mechanisms enabling bobcats to recolonize this fragmented agricultural landscape. We determined space use and habitat selection of bobcats by radiocollaring 68 bobcats in south-central Iowa during 2003–2006. We triangulated 12,966 locations and recovered an additional 1,399 3-dimensional locations from Global Positioning System collars. We used a fixed kernel estimator to calculate 95% utilization distributions (UDs) for home ranges and 50% UDs for cores. Annual home range area of males (x̄ = 58.6 km2, 95% CI = 49.2–69.9) was nearly 3 times that of females (x̄=19.9 km2, 95% CI = 17.0–23.3). Females used smaller home ranges during April-September when they were suspected to have kittens with them (x̄ = 16.8 km2, 95% CI = 13.7–20.7), as compared to October-March (x̄ = 24.1 km2, 95% CI = 19.0–30.7), whereas home ranges of males did not differ between seasons. Similarly, core area of males (x̄ = 7.7 km2, 95% CI = 6.2–9.6) was larger than that of females (x̄ = 2.3 km2, 95% CI = 1.9–2.7). Females used significantly smaller cores in April-September (x̄ = 1.8 km2, 95% CI = 1.4–2.3) as compared to October-March (x̄ = 2.8 km2, 95% CI = 2.2–3.7), whereas males did not. For both sexes, compositional analysis indicated that forest habitat was ranked higher than all other habitat classes at both the landscape and local scale. Standardized habitat selection ratios illustrate that female and male bobcats selected forest habitat about twice as frequently as any other habitat class, including grassland and Conservation Reserve Program land. Predictive models indicated that home range and core area was smaller in landscapes where perennial forest and grassland habitats were less fragmented. Predictive models indicated home ranges were more irregular in shape in landscapes where row crop patches were less aggregated within home ranges. Our results have practical implications for wildlife managers regarding expected bobcat habitat use and distribution as the species becomes more abundant in the agricultural landscape of the Midwest. 相似文献
18.
Sophie Monsarrat Simon Benhamou Fran?ois Sarrazin Carmen Bessa-Gomes Willem Bouten Olivier Duriez 《PloS one》2013,8(1)
Feeding stations are commonly used to sustain conservation programs of scavengers but their impact on behaviour is still debated. They increase the temporal and spatial predictability of food resources while scavengers have supposedly evolved to search for unpredictable resources. In the Grands Causses (France), a reintroduced population of Griffon vultures Gyps fulvus can find carcasses at three types of sites: 1. “light feeding stations”, where farmers can drop carcasses at their farm (spatially predictable), 2. “heavy feeding stations”, where carcasses from nearby farms are concentrated (spatially and temporally predictable) and 3. open grasslands, where resources are randomly distributed (unpredictable). The impact of feeding stations on vulture’s foraging behaviour was investigated using 28 GPS-tracked vultures. The average home range size was maximal in spring (1272±752 km2) and minimal in winter (473±237 km2) and was highly variable among individuals. Analyses of home range characteristics and feeding habitat selection via compositional analysis showed that feeding stations were always preferred compared to the rest of the habitat where vultures can find unpredictable resources. Feeding stations were particularly used when resources were scarce (summer) or when flight conditions were poor (winter), limiting long-ranging movements. However, when flight conditions were optimal, home ranges also encompassed large areas of grassland where vultures could find unpredictable resources, suggesting that vultures did not lose their natural ability to forage on unpredictable resources, even when feeding stations were available. However during seasons when food abundance and flight conditions were not limited, vultures seemed to favour light over heavy feeding stations, probably because of the reduced intraspecific competition and a pattern closer to the natural dispersion of resources in the landscape. Light feeding stations are interesting tools for managing food resources, but don’t prevent vultures to feed at other places with possibly high risk of intoxication (poison). 相似文献
19.
Estrada A Luecke L Van Belle S Barrueta E Meda MR 《Primates; journal of primatology》2004,45(1):33-39
Surveys of populations of spider and howler monkeys were conducted at the Mayan sites of Calakmul and Yaxchilán, Mexico and Tikal, Guatemala. The forests in which these sites are found are part of the largest landmass of tropical rain forests present in Mesoamerica, encompassing about 4 million ha. Triangulation of monkey vocalization combined with ground surveys was used to determine the presence of howler and spider monkey groups. Howler monkey mean troop size at these sites varied from 6.6±2.1 individuals in Yaxchilán to 7.5±1.9 in Calakmul to 8.7±2.2 in Tikal. Density estimates varied from 12.8 individuals/km2 in Yaxchilán to 15.2 individuals/km2 in Calakmul to 17.8 individuals/km2 in Tikal. Mean spider monkey subgroup size varied from 4.7±2.6 individuals in Tikal to 5.6±3.0 individuals in Yaxchilán to 7.7±3.8 individuals in Calakmul. Spider monkey density varied from 17.0 individuals/km2 in Yaxchilán to 17.2 individuals/km2 in Calakmul to 56.4 individuals/km2 in Tikal. All sightings of both howler and spider monkeys at the three sites were in undisturbed rain forest vegetation and spider monkeys in general were more frequently sighted at higher tree heights than howlers. We discuss the value of further acquiring data on howler and spider monkey populations existing in extensive forest tracts and on the conservation value for both primate species of the forests surrounding the Mayan ruins found in this area of Mesoamerica. 相似文献
20.
Understanding the nature of the interactions between humans and wildlife is of vital importance for conflict mitigation. We equipped five leopards with GPS-collars in Maharashtra (4) and Himachal Pradesh (1), India, to study movement patterns in human-dominated landscapes outside protected areas. An adult male and an adult female were both translocated 52 km, and exhibited extensive, and directional, post release movements (straight line movements: male = 89 km in 37 days, female = 45 km in 5 months), until they settled in home ranges of 42 km2 (male) and 65 km2 (female). The three other leopards, two adult females and a young male were released close to their capture sites and used small home ranges of 8 km2 (male), 11 km2 and 15 km2 (females). Movement patterns were markedly nocturnal, with hourly step lengths averaging 339±9.5 m (SE) during night and 60±4.1 m during day, and night locations were significantly closer to human settlements than day locations. However, more nocturnal movements were observed among those three living in the areas with high human population densities. These visited houses regularly at nighttime (20% of locations <25 m from houses), but rarely during day (<1%). One leopard living in a sparsely populated area avoided human settlements both day and night. The small home ranges of the leopards indicate that anthropogenic food resources may be plentiful although wild prey is absent. The study provides clear insights into the ability of leopards to live and move in landscapes that are extremely modified by human activity. 相似文献