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1.
Feeding Competition and Agonistic Relationships Among Bwindi <Emphasis Type="Italic">Gorilla beringei</Emphasis> 总被引:2,自引:2,他引:0
Martha M. Robbins 《International journal of primatology》2008,29(4):999-1018
Testing predictions of socioecological models, specifically that the types of feeding competition and social relationships
female primates exhibit are strongly influenced by the distribution, density, and quality of food resources, requires studies
of closely related populations of subjects living under different ecological conditions. I examined feeding competition and
the resulting female social relationships in mountain gorillas (Gorilla beringei beringei) of Bwindi Impenetrable National Park, Uganda, which has ecological conditions distinctive from those where other gorilla
populations live. I observed 1 group of gorillas for 29 mo to examine the proportion of time spent foraging on fruit, the
relationship between patch size and occupancy patterns of fruit trees, and agonistic interactions. Patch occupancy time while foraging in fruit trees decreased with increasing number of gorillas in a tree and decreasing
tree size, suggesting that fruit trees represent limiting patches and can lead to intragroup scramble competition. Gorillas
exhibited higher levels of aggression while feeding on fruit versus other food resources, which indicates intragroup contest
competition. I observed a linear dominance hierarchy with no bidirectionality via displacements, and a similar hierarchy via
aggression, though a notable proportion of the dyads contained 2-way interactions. However, most aggression was of low intensity
(vocalizations) and the recipient typically ignored it. Despite differences in ecological conditions and diet between the
Virunga Volcanoes and Bwindi, agonistic relationships among females are largely similar in the 2 populations and are best
characterized as dispersal individualistic. 相似文献
2.
Researchers consider group size in primates to be determined by complex relationships among numerous ecological forces. Antipredator benefits and better resource defense are the primary pressures for large groups. Conversely, intragroup limited food availability, can result in greater intragroup feeding competition and individual energy expenditure in larger groups, creating energetic advantages for individuals in small groups and placing an upper limit group size. However, the extent to which food availability constrains group size remains unclear for many species, including black howlers (Alouatta pigra), which ubiquitously live in small social groups (≤10 individuals). We studied the relationship between group size and 2 key indices of feeding competition—day journey length and activity budgets—in 3 groups of wild Alouatta pigra at a hurricane-damaged site in Belize, Central America. We controlled for differences in food availability between home ranges (food tree density) and compared both indicators of feeding competition directly with temporal variation in food availability for each group. Our results show no consistent association between resource availability, group size, and either index of competition, indicating that feeding competition does not limit group size at the site—i.e., that larger groups can form without increased costs of feeding competition. The results support the search for other explanations, possibly social ones, for small group size in the primates, and we conclude with suggestions and evidence for such alternative explanations. 相似文献
3.
In primate species with unidirectional dominance relationships, rank order restricts the access of nondominant females to
clumped resources. However, females might attempt to bypass the rank order by reaching feeding sites before the highest ranking
individuals (early arrival tactic) when there are net benefits. We therefore analyzed the order of arrival to the feeding
site of the adult members of a captive group of long-tailed macaques. We used 2 experimental conditions that differed in the
spatial distribution of a fixed amount of food (large vs. small patch). Though each condition induced contest competition,
it was stronger in the small-patch condition. Arrival order does not correlate with dominance rank in either experimental
condition. The α-male and α-female reached the feeding site 10–30 s after the beginning of the test. Some females seized on
opportunities to reach the feeding site before them, especially in the large-patch condition. They used the early arrival
tactic when the risks of aggression were relatively low, which subjects accomplished either by being dominant or by being
nondominant but tolerated by the α-male. Social tolerance may provide individuals with an alternative means to obtain resources.
In sum, variation in food abundance and distribution may affect the extent to which rank order determines order of arrival
to feeding sites. A higher rank may confer priority in the choice of tactics, but not necessarily priority of access to the
resources themselves. 相似文献
4.
Liu Zhensheng Wang Xiaoming Li Zhigang Cui Duoying Li Xinqing 《Frontiers of Biology in China》2007,2(1):100-107
The feeding habitat selection of blue sheep (Pseudois nayaur) was studied by direct observation method in the Helan Mountains, China during winter (from November to December) and spring
(from April to June) from 2003 to 2004. We established 25 line transects to collect information on feeding habitats used by
blue sheep. Blue sheep in the study area preferred mountain savanna forests, a habitat dominated by Ulmus glaucescens, with medium tree density (<4 individuals / 400 m2), moderate tree height (4–6 m), higher shrub density (> 5 individuals / 100 m2), higher shrub (> 1.3 m), higher food abundance (> 50 g), moderate distance to human disturbance (< 500 m), and mild distance
to bare rock (< 2 m). Such habitats characterized by 12 ecological factors were preferred as feeding areas by blue sheep during
winter. Similar to habitat selection by the species during winter, blue sheep also showed a preference for mountain savanna
with tree dominated by Ulmus glaucescens and medium tree density (< 4 individuals / 400 m2) during spring. Nevertheless, blue sheep preferred medium tree height (< 6 m), moderate tree density (5–10 individuals /
100 m2), medium shrub height (1.3–1.7 m), higher food abundance (> 100 g), moderate altitude (< 2 000 m), moderate distance to water
resource (< 500 m), and medium hiding cover (50%–75%) during spring. Selection of the feeding habitats by sheep showed a significant
difference in vegetation type, landform feature, dominant tree, tree height, shrub density, distance to the nearest shrub,
food abundance, slope direction, slope degree, distance to water resource, and hiding cover between winter and spring. Results
of principal components analysis indicated that the first principal component accounted for 24.493% of the total variance
among feeding habitat variance during winter, with higher loadings for vegetation type, dominant tree, tree height, distance
to the nearest tree, shrub density, shrub height, altitude, distance to water resource, and distance to human disturbance.
In spring, the first principal components explained 28.777% of the variance, with higher loadings for vegetation type, distance
to the nearest tree, shrub height, distance to the nearest shrub, food abundance, altitude, and distance to human disturbance.
Translated from Zoological Research, 2005, 26(6): 580–589 [译自: 动物学研究] 相似文献
5.
Erin P. Riley 《International journal of primatology》2007,28(1):107-133
I examined how Sulawesi Tonkean macaques (Macaca tonkeana) respond in terms of their diet and activity patterns to anthropogenic habitat alteration in Lore Lindu National Park, Sulawesi,
Indonesia. Anthropogenic habitat alteration comprised clearing of forest for agriculture and small-scale forest product collection.
I quantified the diet and activity of 2 groups (CH and Anca), occupying habitats with different levels of alteration, via
scan sampling. Tree abundance, key food specific density, and fruit production were greater in the minimally altered habitat
(CH), substantiating the characterization of the group’s habitat as higher quality. For the group in the heavily altered habitat
(Anca), alternative foods, e.g., insects, fungus, young and mature leaves, shoots, and stems, accounted for a significantly
greater proportion of the diet. Dietary diversity is significantly lower in the Anca group, with 52% of their diet being palm
fruits from Arenga pinnata. The activity patterns of the Anca group—more time foraging, less time moving, and more time resting than the CH group—reflect
the lower resource availability in their habitat and their reliance on more alternative food items, coupled with their extremely
small group size (6–9 individuals). The group may be at the optimal size in which foraging efficiency is maximized for the
habitat, a response, in conjunction with dietary and behavioral flexibility, to alteration of their habitat. The results are
contextualized with respect to the conservation value of human-modified landscapes. 相似文献
6.
贺兰山岩羊冬春季取食生境的比较 总被引:10,自引:2,他引:8
2003年11~12月和2004年4~6月,在贺兰山设定了25条固定样线,采用直接观察法对岩羊冬春季的取食生境选择进行了研究。结果表明,岩羊冬季对12种取食生境生态因子有选择性,偏爱选择位于山地疏林草原带,优势乔木为灰榆,乔木密度〈4株、高度4~6m,灌木密度〉5株、高度〉1.3m,食物质量〉50g,人为干扰距离〈500m,距裸岩距离〈2m的地方取食。而春季对11种取食生境生态因子有选择性,偏爱选择山地疏林草原带,优势乔木为灰榆,乔木密度〈4株、高度〈6m,灌木密度5~10株、高度1.3~1.7m,食物质量〉100g,海拔高度〈2000m,距水源距离〈500m,隐蔽级50%~75%的地点。冬春季岩羊对植被类型、地形特征、优势乔木、乔木密度、乔木高度、灌木密度、灌木距离、食物丰富度、坡向、坡度、距水源距离、人为干扰距离和隐蔽级的选择存在显著差异。主成分分析表明,冬季第1主成分的贡献率达24.493%,其中绝对值较大的权系数出现在植被类型、优势乔木、乔木高度、乔木距离、灌木密度、灌木高度、海拔高度、距水源距离和人为干扰距离等生态因子:春季第1主成分的贡献率达28.777%,其中绝对值较大的权系数出现在植被类型、乔木距离、灌木高度、灌木距离、食物丰富度、海拔高度和人为干扰距离等生态因子。随着北方地区冬春季食物数量和质量的剧烈变化,贺兰山岩羊对取食生境的利用对策也将发生一定程度的改变,与其他分布区的岩羊相比,贺兰山独特的地理位置和特殊生境使其在取食生境选择上存在很大差异。 相似文献
7.
We examined the spatial and temporal distribution of the foods of ursine colobus (Colobus vellerosus) at Boabeng-Fiema, Ghana as a means to predict the monopolizablity and usurpability of their food resources. Recent evidence
suggests that food may not be limiting for folivorous primates, and that male sexual coercion may be a more important influence
on folivore social organization. To address the question, we collected focal data on the feeding behavior of adult females
and males over 11 mo (September 2000-August 2001) on 2 groups: WW (n = 31–33 individuals) and B (n = 8–16 individuals). We also conducted phenological monitoring and a tree survey of the two-group home ranges to establish
food availability and distribution. We used 2 behavioral or organism-defined indicators of feeding behavior to assess potential
resource contestability: food site residence time and distance moved between food sites. The colobus fed on a high diversity
of species, most of their food trees were not clumped in distribution, within-tree interfood distances were short, and food
trees were large. The only condition associated with the potential for monopolization was low food tree density. However,
low food tree density may be offset by the colobus’ use of large trees. Taken together, the ecological and behavioral indicators
suggest the food resources of Colobus vellerosus had a low potential for monopolization. Our results also indicate mature leaves had the longest food site residence time,
which may suggest they should be the most usurpable plant part, though their presumed low quality and high abundance probably
counteracted the effect. The pattern implied the potential for direct feeding competition among Colobus vellerosus at Boabeng-Fiema was low and agonistic interactions over food are not expected. Instead, a group size effect on feeding efficiency
should be a more predominant influence on feeding efficiency, if food is limiting for the species. 相似文献
8.
Digestion is an important process in understanding the feeding ecology of animals. We examined digesta passage time, digestibility,
and total gut fill in Japanese macaques (Macaca fuscata; n = 4) under 4 dietary conditions representing the seasonal and regional variations in the diets of wild populations to determine
the effects of food type and food intake on these digestive features. Food type is associated with mean retention time (MRT),
digestibility, and total gut fill. Dry matter intake (DMI) of food correlates positively with total gut fill but not with
MRT or digestibility. Conversely, indigestible DMI affected MRT negatively. Thus, when Japanese macaques consume high-fiber
foods, MRT becomes shorter and digestibility is lower than when eating low-fiber foods. Moreover, macaques experience increases
in total gut fill when they consume high-fiber diets or a large amount of food. Japanese macaques may excrete difficult-to-digest
food components quickly; they nevertheless buffer an increase in food intake by an increase in gut fill. Our study offers
new insights into the relationship between feeding ecology and nutritional physiology in primates by simultaneously examining
the effects of food type and intake level on MRT and digestibility. 相似文献
9.
The feeding habitat selection of blue sheep (Pseudois nayaur)was studied by direct observation method in the Helan Mountains,China during winter (from November to December)and spring (from April to June)from 2003 to 2004.We established 25 line transects to collect information on feeding habitats used by blue sheep.Blue sheep in the study area preferred mountain savanna forests,a habitat dominated by Ulmus glaucescens,with medium tree density (<4 individuals/400 m2),moderate tree height (4-6 m),higher shrub density (>5 individuals/100 m2),higher shrub (>1.3 m),higher food abundance (>50 g),moderate distance to human disturbance (<500 m),and mild distance to bare rock (<2 m).Such habitats characterized by 12 ecological factors were preferred as feeding areas by blue sheep during winter.Similar to habitat selection by the species during winter,blue sheep also showed a preference for mountain savanna with tree dominated by Ulmus glaucescens and medium tree density (<4 individuals/400 m2)during spring.Nevertheless,blue sheep preferred medium tree height (<6 m),moderate tree density (5-10 individuals/100 m2),medium shrub height (1.3-1.7 m),higher food abundance (>100 g),moderate altitude (<2 000 m),moderate distance to water resource (<500 m),and medium hiding cover (50%-75%)during spring.Selection of the feeding habitats by sheep showed a significant difference in vegetation type,landform feature,dominant tree,tree height,shrub density,distance to the nearest shrub,food abundance,slope direction,slope degree,distance to water resource,and hiding cover between winter and spring.Results of principal components analysis indicated that the first principal component accounted for 24.493%of the total variance among feeding habitat variance during winter,with higher loadings for vegetation type,dominant tree,tree height,distance to the nearest tree,shrub density,shrub height,altitude,distance to water resource,and distance to human disturbance.In spring,the first principal components explained 28.777%of the variance,with higher loadings for vegetation type,distance to the nearest tree,shrub height,distance to the nearest shrub,food abundance,altitude,and distance to human disturbance. 相似文献
10.
Synopsis We hypothesized that blue tang, Acanthurus coeruleus, territories on sites with low biogenic structure would be larger than territories on sites with relatively high biogenic
structure due to differences in the amount and distribution of resources. We tested this hypothesis by tracking blue tang
over uncolonized pavement and reef crest, two habitat types at opposite ends of the habitat structure spectrum. We recorded
density, feeding rates and aggression events in order to evaluate our findings in the context of a territory model and the
ideal free distribution model. Territories of A. coeruleus averaged nearly four times larger on pavement sites than on reef crest sites. Conversely, densities of A. coeruleus were significantly lower on pavement sites. While there was no significant difference in the average rates of movement between
habitats, average turning angles were significantly higher on reef crest. There were no significant differences in feeding
rates between habitats, suggesting that higher territory sizes and lower densities may allow fish on uncolonized pavement
to match resource acquisition of fish on reef crest. The insignificant difference of aggression encounters between habitats
suggests that movement and density differences among habitats are not solely legacies of differential settlement. 相似文献
11.
贺兰山马鹿冬季取食和卧息生境选择 总被引:3,自引:1,他引:3
2007 年12 月至2008 年1 月,在贺兰山地区,利用痕迹检验法和直接观察法对马鹿阿拉善亚种的冬季取食和卧息生境选择进行研究。通过在选定的15 条沟段里进行调查,共测定了72 个取食利用样方,59 个卧息利用样方和131 个对照样方的18 种生态因子。结果表明,马鹿在冬季偏好的取食地为平滑起伏坡,以酸枣、柳为优势乔木、混合型树林或空地,乔木高大稀疏、间距较远,灌木密度大,草本盖度较高,位于< 15°的半阴半阳坡的下坡位,距裸岩远,隐蔽度高;偏好的卧息地在山地疏林草原带的平滑起伏坡上,以酸枣、柳为优势乔木、混合型树林或空地,乔木高大稀疏,灌木矮小、稀疏且距离较远,草本盖度较高,位于< 15°阳坡的下坡位,远离裸岩,隐蔽程度高。马鹿冬季的取食和卧息生境在草本盖度和隐蔽度上差异极显著。相对于卧息生境,马鹿冬季的取食生境对草本盖度和隐蔽度要求更低一些。马鹿冬季取食地的资源选择函数为1.155 - 0.149 × 乔木高度- 0.066 × 草本盖度+ 0.190 × 坡度,模型的正确判别率为86.8% ;马鹿冬季卧息地的资源选择函数为- 30.936
+ 0.494 × 乔木高度+ 0.257 × 坡度-0.002 × 海拔高度+ 0.387 × 隐蔽度,模型的正确判别率为95.8% 。食物、隐蔽条件以及贺兰山的独特地形特征是影响马鹿冬季取食和卧息生境选择的主要因素。 相似文献
+ 0.494 × 乔木高度+ 0.257 × 坡度-0.002 × 海拔高度+ 0.387 × 隐蔽度,模型的正确判别率为95.8% 。食物、隐蔽条件以及贺兰山的独特地形特征是影响马鹿冬季取食和卧息生境选择的主要因素。 相似文献
12.
Stefan L. Arriaga-Weiss Sophie Calmé Christian Kampichler 《Biodiversity and Conservation》2008,17(1):173-190
The effects of habitat loss and fragmentation in tropical forests are difficult to separate, as they usually occur concurrently.
In the state park La Sierra, in Tabasco, Mexico, the rainforest is being cleared for pasture, and fragments are being used
by local inhabitants. This study examined the response of bird feeding guilds to habitat characteristics, including human
disturbance, in five fragments of different sizes (1 ∼ 4,500 ha, 2 ∼ 150 ha, and 2 ∼ 80 ha). Using point count observations,
125 species were recorded and were grouped into 11 feeding guilds. As expected, the largest fragment had higher species richness
and abundances than the smaller fragments. However, five habitat features differed significantly among fragment sizes, including
tree density, the number of tree stumps and the number of trails. Thus the larger fragment was also less disturbed. Fragment
size alone was significant only for scavenger species richness, and for the abundance of bark gleaning insectivores and insectivore/nectarivores.
Raptors were more diverse and abundant in the large fragment and less disturbed sites. Arboreal frugivores and bark or foliage
gleaning insectivores, depended on higher trees and less disturbed sites. A better understanding of the mechanisms that affect
persistence is essential for the planning of conservation actions. 相似文献
13.
Ryota Kawanishi Mikio Inoue Motohiro Takagi Yo Miyake Takaaki Shimizu 《Ichthyological Research》2011,58(3):202-208
We examined habitat factors related to the distribution and abundance of the spinous loach Cobitis shikokuensis, an endangered benthic fish, in the Shigenobu River system, southwestern Japan. In the study river, the spinous loach was
distributed widely along the main stem, from headwater to near the mouth, whereas it was rarely found in tributary streams.
Classification tree analysis showed that the presence/absence of spinous loach was explained by a combination of percent pebble
and length of river fragment between artificial barriers. Spinous loach incidence was high in sites with abundant pebble (>27.7%),
but low in sites with short river fragment (≤0.97 km) even if pebbles were abundant. A regression tree model for loach density
retained only percent pebble as a single best predictor, with sites with higher percent pebble (>40.4%) having higher density.
These results suggest that substrate condition is an important factor determining the distribution and abundance of spinous
loach and also that habitat fragmentation by artificial barriers has great potential to threaten the spinous loach population
in this river. Considering the highly fragmented situation of the study river and prevention of upstream migration by barriers,
we conclude that maintenance of suitable habitats in upper reaches has high priority for conservation of the spinous loach. 相似文献
14.
Naoki Agetsuma 《International journal of primatology》1994,15(5):595-609
I investigated the activity budget and diet of Yakushima macaques (Macaca fuscata yakui,)in warm temperate broad- leaved forest of Yakushima, Japan. Both time spent feeding and time spent moving varied considerably
between half- months. However, total time spent in active behaviors— feeding time plus moving time— was stable. The composition
of the diet also showed considerable variation between half- months. The macaques fed mainly on fruits, seeds,mature leaves, fallen seeds, flowers, and young leaves, each of which accounted for more than 30% of feeding time in at least
1 half- month. They also ate insects and fungi, but each of them comprised ≤ 25 and ≤ 8% of feeding time in any half- month,
respectively. Time spent feeding on mature leaves, young leaves, flowers, or fallen seeds is positively correlated with total
time feeding and is negatively correlated with time moving. In contrast, time feeding on fruits, seeds, insects or fungi is
negatively correlated with time feeding and is positively correlated with time moving. Foraging on foods that have a low energy
content, a high density, and a relatively even distribution— mature leaves— or that need much manipulation to be processed—
flowers and fallen seeds— increased feeding time, while foraging on foods for which monkeys must search intensively in the
forest— fruits, seeds, insects, and fungi— led to increased moving time. I examined foraging strategies of Yakushima macaques
in terms of moving costs and the quality of food items. Regarding time feeding on fruits, which have more energy and may need
less manipulation than other foods, as a benefit, and moving time as a cost, they seemed to employ a strategy that balanced
the costs and benefits of foraging. 相似文献
15.
Juan Carlos Riveros Colleen M. Schaffner Filippo Aureli 《International journal of primatology》2017,38(5):856-871
Group living leads to competition for food between group members. Two types of intragroup food competition may occur: scramble competition, in which all group members use the same resource, such that feeding opportunities are equal for everyone; and contest competition, in which some group members monopolize resources through aggression and dominance. In species in which females disperse from the natal group and immigrate into other groups, immigrant females increase group size and thus possibly food competition. Under these circumstances, other females may use aggression to discourage new females from joining the group. We assessed the distribution of aggression, embraces, and kisses among female spider monkeys (Ateles geoffroyi) in relation to group tenure. We recorded social interactions during 1688 10-min focal animal samples on 11 females in Santa Rosa, Costa Rica. We found that aggression was rare between long-term resident females and aggression rates were not higher during feeding than in other contexts, suggesting there was little contest competition. Long-term residents and less recently immigrant females showed higher aggression rates toward the most recent immigrants than toward other females, especially during the first months after a female immigrated, which coincided with the dry season. We did not find similar patterns for embrace and kiss. These results suggest that other females target aggression toward the most recent immigrants to reduce scramble competition. This finding suggests that group tenure should be included in socioecological models for species with female dispersal. 相似文献
16.
Govindhaswamy Umapathy Shaik Hussain Sisinthy Shivaji 《International journal of primatology》2011,32(4):889-900
Habitat fragmentation is considered the most serious threat to primate conservation in the tropics, and understanding it effects
on lion-tailed macaque is very important because most of the populations live in fragmented habitats. We examined demographic
parameters of 9 lion-tailed macaque groups in 8 rain forest fragments with reference to fragment area, tree density, canopy
cover, tree height, and total basal area of food trees. Group size ranged from 7 to 90 individuals but was not related to
habitat variables. Birth and growth rates of groups did not differ significantly between small (n = 4) and large (n = 4) fragments. Tree density, canopy cover, and total basal of food trees all show strong positive correlations with fragment
area. Growth rate correlates with tree density, but there are no other significant relationships between birth or growth rate
and habitat variables. The percentage of immature individuals in the group is significantly positively associated with the
total basal area of food trees, but not with any other habitat variable. Comparison of our data from this study with data
available for the same population in 1996 indicates a slight decline in birth rate but an increase in total number of individuals,
from 154 to 242. Of the 5 small fragment groups, 3 have increased in size since 1996 while the sizes of the other 2 groups
have remained the same. Based on this study, we advocate that to manage the fragile lion-tailed macaque groups the following
steps need to be taken: 1) create dispersal corridors between the fragments using fruit trees to facilitate male dispersal,
2) construct canopy bridges across the prevailing roads, 3) protect the fragments from further degradation, and 4) periodically
monitor these populations for long-term conservation. 相似文献
17.
Conservation of wildlife populations requires extensive knowledge of their habitat requirements, efficient methods to evaluate habitat quality, and an understanding of the value of fragments and edges. Kibale National Park, Uganda has areas that differ in the densities of 2 species of frugivorous monkeys—Cercopithecus mitis and Lophocebus albigena—including one on an edge and forest fragments outside the park that lack both species. We compared the basal area densities of important food trees with primate densities. The density of Cercopithecus mitis correlates most strongly with the basal area density of all types of food trees combined. The density of Lophocebus albigena does not correlate with the basal area densities of any category of food trees or with fruit availability. An index of their density—number of groups seen per km walked—correlates to fruit availability but with marginal significance. Lack of a relationship between the basal area densities of food trees and density of Lophocebus albigena may be the result of a mismatch in scale between the forest area measured and their large home ranges. We compared the unused area of forest to the other areas of the forest and the fragments and found it had higher basal area densities in all food tree categories for both species than the fragments and lower basal area densities of most categories than the other parts of the forest, indicating that the fragments are poor quality and would probably be unused even if dispersal were likely. 相似文献
18.
Microhabitat factors associated with forage and bed sites of Indian muntjac (Muntiacus muntjak) were examined and compared in Hainan Island from 2001 to 2002. Habitat characteristics at forage and bed sites were measured by tracking five radio-collared adult muntjacs (three females, two males) and locating from fresh sign or muntjac flushed during transect surveys. Among six available habitat types, Indian muntjac preferred shrub grassland and thorny shrubland, and used dry savanna in proportion to its availability. Muntjac avoided woods, cultivated grassplot and deciduous monsoon forests. Comparing forage sites with bed sites, food availability was greater at forage sites. For bed sites, taller trees with larger canopies, taller shrubs, denser shrub canopy covers and concealment covers were essential factors. No seasonal difference (wet season vs. dry season) was found in food abundance at either forage sites or at bed sites. During the wet season, canopy closure for both types of sites was higher and at bed sites concealment cover was higher than during the dry season. Principal component analysis indicated that tree height, d.b.h. and maximum canopy diameters were important factors in habitat selection. The different microhabitat characteristics at forage and bed sites can be a clue to understanding the survival strategy of Indian muntjac, a small-bodied ungulate, in savanna woodlands. 相似文献
19.
20.
Carey P. Yeager 《International journal of primatology》1996,17(1):51-62
I studied long- tailed macaque (Macaca fascicularis)feeding behavior and ecology as part of a larger behavioral ecological study at the Natai Lengkuas Station, Tanjung Puting
National Park, Kalimantan Tengah, Indonesia. I collected data on feeding behavior via scan sampling of all visible individuals
in the focal group (approximately 800 observation hours). I established vegetational plots and monitored them monthly to determine
food availability and abundance. I found long- tailed macaques to be primarily frugivorous;leaves, flowers, insects and bark provided the remainder of the diet. They used at least 33 plant species as food sources,
but >60% of the diet was provided by only 5 species. Based on previous vegetational analyses, these tree species were among
the highest in relative density. However, selection ratios for 19 food species indicate that 13 of them were selected more
often than expected. Long- tailed macaques appear to be selective feeders but can exploit a variety of food sources during
periods of food scarcity. 相似文献