广西扶绥白头叶猴的欺骗信号

1997年9月至1998年9月,我们在广西扶绥珍贵动物保护区对白头叶猴(Trachypithecus leucocephalus)进行保护生物学研究。在本研究中,我们试图评价生境质量的下降对白头叶猴生存造成的负面影响。我们用系统的方法采集行为数据,用典型的野外记录技术(ad libitum)记录稀少行为事件。观察结果表明,生活在高质量生境中的猴群极力地保卫其家域;相反地,生活在低质量生境中的猴群不尽力保卫其家域。群体中的繁殖雄性在雄性替代过程中一旦被逐出群外,就会变成孤猴,并失去家域。这时,由于生境质量低劣,孤猴将面临食物短缺。我们的观察显示,这些猴子通过欺骗信号保持群间距离,使其得以呆在有食物资源的生境中。依据Zahavi的理论,在通讯行为中,信号接受者总是在检查信号发出者,防止其发出欺骗信号。因此,可以预测欺骗信号无法得以演化。然而,我们的观察结果不支持这种预测。     

广西扶绥白头叶猴对栖息地的选择与利用

为了解白头叶猴（Trachypithecus leucocephalus）的栖息地利用规律及其影响因素,2016年2月至2017年1月,采用瞬时扫描取样法对广西崇左白头叶猴国家级自然保护区一群白头叶猴的栖息地利用进行了研究。结果表明,白头叶猴对山体不同部位的利用存在显著性差异（χ² =39.467,df=3,P<0.001）,其中,对崖壁（56.75±9.55）%的利用比例最大,其次是对山坡（39.42±10.93）%和山顶（2.98±2.54）%的利用,而对山脚（0.84±1.47）%的利用频率最低。白头叶猴对不同微生境类型的利用存在差异（χ²=27.709,df=3,P<0.001）,其中对乔木（49.37±12.31）%的利用比例最大,其次是裸岩（24.05±13.61）%,随后依次为藤本（15.48±8.01）%和灌木（10.87±5.45）%。白头叶猴主要在山坡上觅食,利用崖壁移动、休息,进行社会活动;主要利用裸岩进行社会活动,觅食、移动、休息主要发生在乔木上。从整体来看,白头叶猴在雨季对乔木的利用频率显著大于旱季（Z=-2.680,n=12,P=0.007）;雨季在山坡觅食频率显著大于旱季（Z=-2.517,n=12,P=0.012）,而在崖壁觅食频率刚好相反（Z=-2.842,n=12,P=0.004）;白头叶猴雨季在乔木休息的频率显著大于旱季（Z=-2.355,n=12,P=0.019）。白头叶猴对栖息地的利用受到温度的影响。白头叶猴对乔木的总体利用频率随着平均温度的升高而增加（r=0.664,n=12,P=0.018）;觅食时,对崖壁、裸岩的利用频率均与平均温度成负相关关系（崖壁：r=-0.685,n=12,P=0.014;裸岩：r=-0.600,n=12,P=0.039）;休息时,对乔木的利用频率与平均温度呈正相关关系（r=0.650,n=12,P=0.022）。不同季节,白头叶猴对栖息地的利用方式不同。白头叶猴的栖息地利用模式可能是在觅食利益和捕食风险之间作出的权衡,并受到环境温度的影响。     

Comparison of locomotor behaviour between white-headed langurs Trachypithecus leucocephalus and Francois' langurs T.fran(c)oisi in Fusui, China

We studied the locomotor behaviour of white-headed langurs Trachypithecus leucocephalus and Fran(c)ois' langurs T.fran(c)oisi to test two hypotheses: (1) these monkeys have evolved locomotor ability to support their activities on limestone hills,and (2) Fran(c)ois' langurs have evolved more diverse locomotor skills than white-headed langurs. Data were collected from 1996 - 1998 and in 2005 in Fusui Nature Reserve,Guangxi,and showed that the two species had similar locomotor types,but Francois' langurs had more locomotor modes (26) than white-headed langurs (12). Quadrupedal walking and leaping were two major types,and white-headed langurs were more arboreal than Fran(c)ois' langurs. We suggest that,while keeping their ancestral locomotor types,the two species have evolved new types allowing them to live on limestone cliffs. Compared to white-headed langurs,Francois' langurs have more diverse locomotor modes that probably have allowed them to live in more habitat types. As an evolutionary outcome,Fran(c)ois' langurs have a larger distribution range.     

Habitat Quality and Activity Budgets of White-Headed Langurs in Fusui,China

Within a species, habitat quality may be a factor causing different activity budgets between populations. The habitat of white-headed langurs (Trachypithecus leucocephalus) has been seriously disturbed in Fusui Rare and Precious Animal Nature Reserve, China, where we carried out a study of their socioecology from September 1997 to September 1998. We collected data on langur activity budgets from the main population located in the central part of a group of limestone hills. We classified habitat quality into 4 grades according to the extent of human disturbance. We showed that the two main study groups of white-headed langurs spent on average 50% of time resting, 13% feeding, 18% moving (including foraging), 11% grooming, and 7% playing. Langur time budgets showed no significant seasonal change, but they differed among different sex-age classes. Infants and juveniles spent about 20.3% of time playing, whereas adults spent only 0.2% playing. The group in high quality habitat engaged less in feeding and more in playing than the group in low quality habitat did. Habitat quality influenced the playing time of young white-headed langurs and may be vital to their successful maturation.     

Effect of habitat fragmentation on ranging behavior of white-headed langurs in limestone forests in Southwest China

The critically endangered white-headed langur (Trachypithecus leucocephalus) is confined to fragmented karst forests of southwest Guangxi Province, China. A lack of information on the influence of habitat fragmentation on langur behavior has prevented a comprehensive understanding of their ranging behavior and the development of effective langur conservation strategies. We collected comparative data on time budgets, daily path lengths, home range and diets of four langur groups inhabiting the lightly fragmented Fusui forest (G1, G2) and the more heavily fragmented Chongzuo forest (G3, G4). The aim was to explore the effect of this fragmentation on langur ranging behavior. Our results showed that the Fusui groups spent more time on moving and less time on feeding and playing than the Chongzuo groups. Daily path lengths were 472.4–536.1 m for the Fusui groups and 449.6–480.7 m for the Chongzuo groups, indicating no marked inter-site variation. The Fusui groups occupied much larger home ranges (23.8–33.8 ha) than the Chongzuo groups (14.5–15.8 ha). However, all groups had similar monthly home ranges. Diets significantly differed among langur groups. The Fusui groups consumed more young leaves and had much lower diet diversity compared with the Chongzuo groups. Our findings indicate that habitat fragmentation is one of the crucial determinants of white-headed langur ranging behavior because fragmentation reduces and restricts the home range. Langurs in fragmented habitat adopt an energy conservation strategy characterized by devoting more time to feeding and less time to moving, with a smaller home range and consumption of more plant species. We argue that linking fragmented forests with corridors should be considered a priority in a wider and comprehensive longer term langur population conservation and habitat management strategy.     

Habitat use of the white‐headed langurs in limestone forest of Southwest Guangxi,China: Seasonality and group size effects

Understanding how animals cope with habitat‐specific environmental factors can assist in species conservation management. We studied the habitat use of four groups (two large and two small groups) of white‐headed langurs (Trachypithecus leucocephalus) living in the forest of southwest Guangxi, China between September 2016 and February 2017 via instantaneous scan sampling. Our results showed that the langurs primarily used hillsides (55.91% ± 6.47%), followed by cliffs (29.70% ± 5.48%), hilltops (7.26% ± 3.55%), flat zones (6.99% ± 6.58%), and farmlands (0.14% ± 0.28%). The langurs moved most frequently on hillsides (49.35% ± 6.97%) and cliffs (35.60% ± 9.17%). The hillsides were more frequently used (66.94% ± 7.86%) during feeding, and the langurs increased the use of hilltops during the rainy season, and the use of cliffs in the dry season. The langurs frequently rested on hillsides (49.75% ± 8.16%) and cliffs (38.93% ± 8.02%). The larger langur group used cliffs more frequently when moving and resting, whereas the small langur group used hillsides more frequently while resting. Langurs in all groups avoided the flat zones for feeding. Their use of habitat reflected the balancing of foraging needs, thermoregulation, and predator avoidance. We conclude that the ecological factors are determinants of habitat use for white‐headed langurs. Our findings suggest that conservation efforts should focus on protecting the vegetation on the hillsides and restoring the vegetation on the flat zones.     

广西弄岗黑叶猴栖息地选择与利用

2005年9月至2006年8月对广西弄岗国家自然保护区内一群黑叶猴进行行为观察,采用瞬时扫描法观察并收集猴群的栖息地利用数据,分析黑叶猴对喀斯特石山栖息地的选择与利用规律。结果表明,黑叶猴对不同山体部位的利用有显著性差异(χ~2=43.063,df=4,P0.001)。黑叶猴对崖壁的利用频率最高(占总记录的36.67%±9.44%),其次是山坡(32.30%±9.57%),对山脚(14.15%±5.01%)、山顶(11.24%±8.42%)和平地(5.63%±2.92%)的利用较少。分析发现,黑叶猴对山体部位的利用没有显著的季节性差异(山顶:Z=-0.160,P=0.837;崖壁:Z=-0.320,P=0.749;山坡:Z=-0.480,P=0.631;山脚:Z=-1.601,P=0.109;平地:Z=0,P=1)。黑叶猴将崖壁作为主要的休息场所,山坡和山脚为主要的移动和觅食场所。黑叶猴对栖息地的利用受食物可获得性的影响。当食物中花的可获得性降低时,猴群增加对山脚的利用;当嫩叶可获得性降低时,猴群增加在崖壁移动的频率;当果实的可获得性升高时,猴群增加在平地觅食的频率。食物组成与黑叶猴栖息地利用也有关系。总体来看,黑叶猴对山顶的利用频率与花的觅食比例呈显著正相关;对山脚的利用频率与果实+种子的觅食比例呈显著正相关。猴群在山顶休息的频率随花和成熟叶的觅食比例的上升而上升;在山脚休息的频率随果实+种子的觅食比例的上升而上升。猴群在山坡觅食的频率随果实+种子的觅食比例的下降而上升;在山脚觅食的频率随嫩叶的觅食比例的下降而上升。另外,平均最低温度与猴群在平地觅食的频率呈负相关关系。分析表明食物的分布和数量对黑叶猴栖息地利用有重要影响,黑叶猴对栖息地的选择是在觅食利益与风险之间进行权衡的结果。     

白头叶猴与黑叶猴觅食行为的比较

开展近缘物种觅食行为比较对理解动物的行为可塑性及适应性具有重要意义。白头叶猴(Trachypithecus leucocephalus)和黑叶猴(T.francoisi)是近缘物种,体形大小相近,社会结构和栖息环境相似,是广西崇左白头叶猴国家级自然保护区喀斯特季节性雨林中邻域分布的灵长类。为了探索两个物种在喀斯特生境中是否有相似的觅食策略,我们于2012年1—12月采用瞬时扫描取样法对两种叶猴的觅食行为进行研究。结果表明,白头叶猴与黑叶猴在不同时段均为叶食性,树叶是两种叶猴各个时段主要食物,其中白头叶猴日均取食树叶77.0%±4.4%,黑叶猴日均取食68.9%±8.3%,两者对树叶的采食比例均没有显著的日时段差异(白头叶猴:χ²=6.602,df=11,P=0.830;黑叶猴:χ²=11.393,df=11,P=0.411)。两种叶猴的觅食行为都在猴群清晨离开夜宿石洞后和进入过夜山洞前的时段中频繁发生。白头叶猴在09:00—10:59和16:00—17:59出现觅食高峰,时间占比分别为41.7%和46.3%;黑叶猴同样在09:00—10:59...     

Habitat suitability and nest survival of white-headed woodpeckers in unburned forests of Oregon

We evaluated habitat suitability and nest survival of breeding white-headed woodpeckers (Picoides albolarvatus) in unburned forests of central Oregon, USA. Daily nest-survival rate was positively related to maximum daily temperature during the nest interval and to density of large-diameter trees surrounding the nest tree. We developed a niche-based habitat suitability model (partitioned Mahalanobis distance) for nesting white-headed woodpeckers using remotely sensed data. Along with low elevation, high density of large trees, and low slope, our habitat suitability model suggested that interspersion–juxtaposition of low- and high-canopy cover ponderosa pine (Pinus ponderosa) patches was important for nest-site suitability. Cross-validation suggested the model performed adequately for management planning at a scale >1 ha. Evaluation of mapped habitat suitability index (HSI) suggested that the maximum predictive gain (HSI = 0.36), where the number of nest locations are maximized in the smallest proportion of the modeled landscape, provided an objective initial threshold for identification of suitable habitat. However, managers can choose the threshold HSI most appropriate for their purposes (e.g., locating regions of low–moderate suitability that have potential for habitat restoration). Consequently, our habitat suitability model may be useful for managing dry coniferous forests for white-headed woodpeckers in central Oregon; however, model validation is necessary before our model could be applied to other locations. © 2011 The Wildlife Society.     

Food Choice of White-Headed Langurs in Fusui,China

We studied the feeding ecology of white-headed langurs (Trachypithecus leucocephalus) from September 1997 to September 1998 in Fusui Rare and Precious Animal Reserve, SW Guangxi, China. We collected data in the central part of a group of limestone hills where the main population pool of langurs was located. The langurs fed on 50 plant species (belonging to 42 genera from 28 families) out of 164 species in the habitat (belonging to 112 genera from 48 families). Most of the food plant species were not common in the habitat. There are 16 important food species, including 6 key species. White-headed langurs were extremely folivorous, feeding mainly on young leaves (75% of total feeding records) of a broad range of less common plant species, which were in less disturbed areas. Thus, langur groups in high quality habitat had greater access to preferred foods, and the future of langurs in the Reserve may depend on immediate cessation of tree felling.     

黑叶猴对广西扶绥破碎生境的选择和利用

从2001年3月至12月,对生活在广西扶绥珍贵动物保护区内-孤立石山上的一群黑叶猴(Trachypithecus francoisi)进行观察.通过收集有关栖息地利用的数据,探讨栖息地的破碎化对黑叶猴生态习性的影响.为分析人类活动对柄息地植被的影响,作者设置了10个植被样方,其中5个位于人类活动频繁的山坡;5个位于人类活动较少的山顶.观察结果表明,山坡的植物种类、多样性以及植物密度均低于山顶;山顶上黑叶猴喜食植物的密度也明显高于山坡.扶绥黑叶猴生境喜好程度分析表明,猴群偏好在食物丰富而人类活动少的山顶休息和觅食,而很少利用人类活动频繁的山坡.雨季里,猴群明显增加对山顶的利用率,而相应地减少对崖壁的利用.因此,扶绥黑叶猴对栖息地选择和利用可能是觅食利益和躲避人类活动干扰权衡的结果.黑叶猴选择崖壁上的突出平台或石洞作为夜宿地;通常重复利用少数几个夜宿地,并且会连续利用同一个夜宿地.     

Food Items Consumed by White-headed Langurs in Fusui, China

We studied the socioecology of white-headed langurs (Trachypithecus leucocephalus) from September 1997 to September 1998 in Fusui Precious Animal Reserve, SW Guangxi, China. We collected data on climate, phenology of food plant species, and foods consumed by langurs living in habitats with different levels of human disturbance. Feeding records showed that the most food is from less common plant species. Young leaves were the staple food item in all langur groups, and consumption correlates with availability. Consumption of mature leaves is not significantly correlated with their availability, but the langurs fed on them, and other food items such as fruits and seeds, when the availability of young leaves was low. Langurs in different areas had broadly similar diets, but they varied most in the proportion of supplementary items such as fruit. Groups in more disturbed habitat did not increase the overall proportion of mature leaves in their diet, but instead maintained their intake of young leaves from a greater diversity of species, and incorporated more immature fruit. Conservationists should direct efforts toward protection of rare plant species providing preferred food items, particularly supplementary foods at times when, and in areas where, preferred food items are less available.     

Food diversity and choice of white-headed langur in fragmented limestone hill habitat in Guangxi,China

We studied the diet and food choice of three groups of white-headed langurs (Trachypithecus leucocephalus) from July 2002 to June 2003 at Fusui Rare Animal Reserve, Guangxi, China. Data were collected from via focus group sampling, with continuous recording. A total of 109 plant species (including 19 unidentified species) were used as food by the white-headed langur. They spent 91.6% of total feeding time feeding on leaves, 4.2% on fruits and 3.3% on stems. Flowers and other food items accounted for only 0.3% and 0.6% of total feeding time, respectively. There were significant seasonal variations in the langurs’ diets with changes in the total number of species and the diversity of food species consumed. The langurs used significantly more plant species as food in the rainy season than in the dry season (36 species vs. 26.5 species). Dietary diversity was also significantly higher in the rainy season than in the dry season (2.6 vs. 2.4). No significant seasonal variation was found in the percentage of various plant parts in their monthly diets. Though the white-headed langur fed on many plant species, 11 species made up 84.9% of their diet. There were no significant correlations between the percentage of feeding time for main food plant species and their corresponding abundance in the habitat, content of water, crude protein, crude fiber and the ratio of crude protein to crude fiber. These results suggest that food choice of the white-headed langur is not influenced by their abundance and nutritional content.     

Habitat use, home range and foraging preferences of the coati Nasua nasua in a pluvial tropical Atlantic forest area

Coatis (genus Nasua ) occupy a large range of forested habitats. The aim of this study was to describe the use of habitat by Nasua nasua in a continuous pluvial tropical Atlantic forest area, the Carlos Botelho State Park (CBSP) in south-eastern Brazil. Use of space by N. nasua in the CBSP was characterized by an average home range area for one group of 445 ha by the minimum convex polygon method and 544 ha by the fixed kernel method, which was used across 2 months; the use of trees for foraging and travelling was superior to that reported for N. nasua and Nasua narica until now, being higher in the drier season. The home range of three coati groups shifted during the 3 years of this study; the home range of one habituated group changed by 91%. The proportion of ground foraging increased with the higher availability of soil invertebrates during the rainy season, but cannot be explained solely on the basis of resource availability.     

上海滨江森林公园重引入獐野放后的活动范围与栖息地选择

本文对重引入后野放于上海滨江森林公园的獐进行无线电遥测跟踪研究,确定其在公园内286个斑块内的有效活动位点,分析其活动范围,并通过Vanderloeg选择系数和Scavia选择指数分析其栖息地选择。结果显示,以最小凸多边形法得到的重引入獐的活动范围面积从 24.94 hm² 至 83.24 hm² 不等,均值为 58.74 hm²;以固定核空间法得到的面积从 11.23 hm² 至 41.52 hm² 不等,均值为 26.93 hm²。野放后的獐偏好选择面积为 1-2 hm² 的较大斑块和距离水源较远的栖息地。在植被因子的选择上,野放后的獐倾向选择野草地为主、乔木和灌木密度适中、乔木高度10-15m、草本高度 30cm 以上的栖息地,避免选择乔木高度低于 5m、草本高度过低（<5cm）和无草本植物分布的栖息地。建议在今后重引入项目实施中,在郊野公园或者其它城市绿林地内为獐营造植被盖度和密度适中、隐蔽性良好、斑块面积适中的栖息地,并补种高草本,促进物种重引入成功。     

Behavioral adjustments and support use of François' langur in limestone habitat in Fusui,China: Implications for behavioral thermoregulation

Climatic factors such as temperature and humidity vary seasonally in primate habitats; thus, behavioral adjustments and microhabitat selection by primate species have been interpreted as behavioral adaptations. François' langur (Trachypithecus francoisi), a native species to southwest China and northern Vietnam, inhabits a limestone habitat with extreme climatic conditions. To understand the potential effects of climatic seasonality on this species, we collected data on the individual behavioral budgets in a T. francoisi group between January and December 2010 in Fusui County, China. Monthly, we performed 5–11 days of observation during this period, using focal animal sampling and continuous recording methods. We also recorded ambient temperature (T_a) and relative humidity (H_r) data at our study site. Results indicated that T_a and H_r were significantly correlated with each other and fluctuated dramatically on a daily, monthly, and seasonal basis. The amount of time spent resting, grooming, basking, and huddling also varied on a daily, monthly, and seasonal basis. The proportion of resting time and total sedentary activity time significantly increased at high and low T_as, respectively. The total sedentary time, resting time, and plant branch use all showed positive significant correlations with T_a. Our results suggest that behavioral adjustment and support use of T. francoisi, at least partly, were related to thermoregulation. T. francoisi minimized thermal stress through behavioral adjustments and support use. It is an adaptive behavior associated with the climatic extremes of limestone habitat. This study can potentially advise conservation management strategies in this specific habitat. Conservation efforts should focus on vegetation restoration in langurs' habitat, including those in the foothills.     

Habitat characterization of western hoolock gibbons Hoolock hoolock by examining home range microhabitat use

Conserving a species depends on an understanding of its habitat requirements. Primatologists often characterize the habitat requirements of primates using macroscale population-based approaches relying on correlations between habitat attributes and population abundances between sites with varying levels of disturbance. This approach only works for species spread between several populations. The populations of some primates do not fulfill these criteria, forcing researchers to rely on individual-based (microscale) rather than population-based approaches for habitat characterization. We examined the reliability of using micro-scale habitat characterizations by studying the microhabitat preferences of a group of wild western hoolock gibbons (Hoolock hoolock) in order to compare our results to the habitat preferences of western hoolock gibbons identified during a macroscale study of populations across Bangladesh. We used stepwise discriminant analysis to differentiate between the areas of low, medium, and high usage based on microhabitat characteristics (tree species availability, altitude, canopy connection, distance from forest edge, and levels of human disturbance). The gibbons used interior forest habitat with low food tree availability most frequently for sleeping and socializing, and used edge habitat containing high food tree availability for medium periods for feeding. These results indicate that the gibbons prefer interior forest but are frequently forced to visit the forest edge to feed. Therefore, the optimal habitat would be interior forest away from human disturbance with high sleeping-tree and feeding-tree availability. These habitat preferences are consistent with the habitat attributes of Bangladesh’s largest remaining western hoolock gibbon populations, which live in areas containing low agricultural encroachment and high food-tree availability. Microhabitat use studies can be used to characterize the habitat requirements of a species, but should include multiple scales of analysis wherever possible.