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1.
The diet and feeding behaviour of the kipunji (Rungwecebus kipunji) was studied over 45 months, the first dietary analysis for this species. During 9498 h of direct observation of 34 kipunji groups, a list of 122 identified foodplants was recorded. The list represents 60 families, including 64 trees, 30 herbs, 9 climbers, 7 shrubs, 6 lianas, 3 grasses and 3 ferns. Kipunji were observed eating bark, young and mature leaves, ripe and unripe fruits, flowers, pith, seed pods, rhizomes, tubers, shoots and stalks. Invertebrates, fungi, moss, lichen, and soil were also eaten. Macaranga capensis var. capensis, an early successional tree, was the most commonly consumed species, with leaves, leaf stalks, pith, flowers and bark all eaten. We demonstrate that the kipunji is an omnivorous dietary generalist, favouring mature and immature leaves, ripe and unripe fruits and bark in similar proportions, with an almost comparable fondness for leaf stalks and flowers. Kipunji appear to be adaptable foragers able to modify their diet seasonally, being more folivorous in the dry season and more frugivorous in the wet. Whereas more ripe fruit is eaten in the wet season, the proportion of unripe fruit remains similar across the year. The proportion of mature leaves and pith increases throughout the dry season at the expense of ripe fruits and bark, and this may compensate nutritionally for the lack of available dry-season ripe fruits. Relatively more pith is eaten in the dry season, more stalks at the end of the dry and beginning of the wet seasons, and bark consumption increases as the rainfall rises.  相似文献   

2.
At an elephant camp in central Myanmar (Burma), we interviewed mahouts and veterinarians to describe the diet of Asian elephants (Elephas maximus) in a mixed-deciduous forest. Elephants showed a broad dietary breadth (103 plant species from 42 families); consumed mostly browse (94% of plant species); and were very selective about plant parts [e.g., many trees were eaten exclusively for their bark (22%) or fruits (14%)]. The fruits from 29 plant species were recorded to be eaten by elephants. Several of these were found as fruit remains, seeds, or seedlings in elephant dung, suggesting a role of Asian elephants in seed dispersal. Work elephants and their mahouts prove to be a rich source of information to understand wild elephant ecology.  相似文献   

3.
The behavior of 118 spruce bark beetles, Ips typographus,was observed on trees under colonization. Most individuals were followed from when they landed until they entered or left the tree. Both males and females spent most time inspecting crevices and searching for a place to start boring or for a hole to enter. These behaviors accounted for 87 and 70% of all behavioral acts recorded for males and females, respectively. Females entered galleries with males only after a period of pushing at the gallery entrance. Males spent on average 3 min and females 4 min on the bark before entering or leaving the tree. Thirty-three percent of the beetles eventually entered the tree, 31% flew away, 35% dropped from the host, and one beetle was eaten by a predator. The results are discussed in relation to the question of mate choice in bark beetles and to studies on attack dynamics of spruce bark beetle populations.  相似文献   

4.
Wood consumption is a rare behavior in frugivorous primates; however, it can be necessary for nutritional balancing as it may provide macro and/or micronutrients that are scarce in the most frequently eaten items (fruits). We tested this hypothesis in six spider monkey (Ateles geoffroyi) communities inhabiting continuous and fragmented rainforests in Lacandona, Mexico. We investigated the importance of both live and decayed wood in the diet of the monkeys, and assessed if wood consumption is related to the nutritional composition of these items. In general, wood consumption was focused on trees of Licania platypus (Chrysobalanaceae) and Ficus spp. (Moraceae), and was similar in continuous forest and in fragments (mean ± SD; 24±20% vs 18±16% of total feeding time, respectively), but marginally higher in females than in males (16±14% vs 5±4%, respectively). Live and decayed wood were both poorer in lipids, proteins, total nonstructural carbohydrates, and total digestible nutrients compared to mature and immature fruits. Moreover, decayed wood of L. platypus showed consistently higher levels of sodium and calcium compared to fruits. In conclusion, our findings suggest that wood from decaying trees of L. platypus and Ficus spp. and young branch piths of L. platypus represents an important source of sodium and/or calcium in the diet of spider monkeys, particularly in the case of females. The protection of decaying trees within forests and fragments is therefore necessary for the appropriate management and conservation of this endangered primate species.  相似文献   

5.
Figs are a critical resource for many tropical frugivores, yet they often are referred to as low quality fruits. To determine their nutritional value, both as a group and for individual species, we analyzed 14 fig species from Barro Colorado Island (BCI), Panama, for fiber, tannins, lipids, protein, carbohydrates, amino acids, and minerals. Seeds and pulp were analyzed separately. Fig fruit pulp consisted of about one‐third digestible components, mostly carbohydrates with some lipids and proteins. Tannin, lignin, and water‐soluble carbohydrates showed considerable variation among species, as did fruit size. Figs contained high amounts of amino acids, such as leucine, lysine, valine, and arginine, and minerals, such as potassium, calcium, magnesium, sodium, and phosphorus. One species, Ficus insipida, contained the highest concentrations of almost all amino acids, many minerals, and protein. Small figs had as much nutritional value per gram as large figs. Free‐standing figs had higher percentages of protein, complex carbohydrates, and ash than strangler figs, which had higher percentages of water‐soluble carbohydrates, tannins, and hemicellulose. The guild of fruit‐eating bats on BCI included ten common species with diets dominated by figs. Fecal analyses and captures at ripe fig trees showed a consistent pattern of resource partitioning. Small bats preferentially ate small‐fruited and strangler figs while large bats consumed mostly large‐fruited and free‐standing figs. Small bats most often ate F. bullenei, which has high levels of lipid and carbohydrates, and F. yoponensis, which has high levels of protein. Medium and large bats most often ate F. insipida, a nutritionally superior species; their second most eaten species was F. obtusifolia, in which the large size may make it efficient to eat. Each bat ate a variety of fig species, supporting the idea that although no single species of fig may be sufficient to sustain frugivores, a mix of fig species can provide a complete set of nutrients.  相似文献   

6.
Volker Nicolai 《Oecologia》1991,88(1):132-137
Summary The arthropod communities living on the bark of the oak species Quercus macrocarpa and Q. ellipsoidalis were investigated in a North American oak savanna. Differences were found in the community structure of the arthropods living on the bark of these two tree species, although they have the same fissured bark type. In the North American oak savanna ecosystem the most important disturbance factor is fire, which maintains species richness. Highest numbers of species and specimens were found at moderately disturbed sites. Three main ecological groups of arthropods living on the bark of trees can be distinguished in relation to the degree of disturbance: (1) Inhabitants of bark of trees restricted to undisturbed sites: they do not occur in fire-disturbed areas; (2) Inhabitants of bark of trees adapted to a moderate degree of disturbance: many species occur in high numbers only in moderately disturbed areas; and (3) Specialist inhabitants of bark of trees in heavily disturbed areas. The number of specimens of these species increases per trunk with the frequency of disturbance.  相似文献   

7.
Partial consumption of acorns by rodents, birds, and insects has been widely reported in various oak species. However, to what extent these partially eaten acorns contribute to the regeneration of oak trees is poorly understood. To date, there is limited knowledge of the effects of seed availability on partial consumption of acorns. Herein, we released tagged Quercus mongolica acorns in two consecutive years with different seed crops, to explore the probability of partial acorn consumption. We also placed simulated partially consumed acorns in the field to investigate their contribution to regeneration of white oak. Our results showed that more acorns were partially eaten in a good crop year than in poor crop year, reflecting an effect of predator satiation on acorn partial consumption by rodents at the population level. Partially eaten acorns were more likely to be damaged at the basal end, suggesting consistent consumption preferences of small rodents. Although, partially consumed acorns were less likely to be scatter-hoarded by small rodents, they germinated more rapidly than the intact acorns in the field, offsetting the negative effects of the non-buried deposition. Despite lower germination rates, lightly damaged acorns exhibited greater growth of roots and shoots, suggesting a compensatory response to partial acorn consumption. Partial consumption may spread predation pressure on acorns and thus appears to be much better for the plant than total consumption by seed-eating animals. Therefore, partially consumed acorns as dispersal leftovers may play a potential role in natural regeneration of Quercus mongolica, especially in mast years. However, this role and the underlying mechanisms of partial acorn consumption by rodents, birds, and herbivore insects need further investigation.  相似文献   

8.
Herbivorous animals face shortages of different minerals in different geographic areas. In the Amazon Basin, sodium is often limiting, driving herbivores to seek supplemental sources. In the lowlands of the western Amazon Basin, parrots commonly consume sodium‐rich soils at clay licks but lick use varies widely among species, and to date, parrots in the region have not been reported consuming other supplemental sodium sources. We document 11 species of psittacines consuming sodium‐rich leaves and trunks of Attalea butyracea palms growing on sodium‐rich soils in lowland Peru. Consumed palms had more sodium and less potassium than uneaten A. butyracea palms and other palm species in the area. Among A. butyracea palm parts, sodium and Na:K ratios were highest in trunks (consumed by parrots in 94% of the 387 foraging bouts recorded) and lowest in leaves (consumed in only 14% of foraging bouts). The low potassium and high Na:K ratio suggest that birds may be seeking not just any sodium sources, but those low in potassium, as potassium is known to exacerbate dietary sodium shortages. Use of the palms and species’ abundance in the study area were not correlated. Instead, parrot species that consumed palms the most were those that use relatively few traditional soil clay licks. This finding suggests that parrot species in the region have fundamental differences in preferred strategies for obtaining supplemental sodium and may help explain documented interspecific differences in geophagy.  相似文献   

9.
On the southeastern coastal plain, the occurrence and abundance of the epiphyte Spanish moss (Tillandsia usneoides L.; Bromeliaceae) are linked to the availability of minerals in the canopy of potential host trees. Trees with high rates of foliar leaching (e.g., cypress and oaks) provide an abundant supply of minerals (Ca, Mg, K, and P) in precipitation collected beneath the canopy. In forests of these species Spanish moss is more abundant and has higher mineral concentrations than in pine forests (e.g., phosphorus 0.04–0.06% dry weight versus 0.03–0.04%). In growth-chamber experiments the growth of Spanish moss increased in response to added phosphorus in the range of concentrations observed in field precipitation collections (0–200 μg/l). In addition to the availability of minerals, the rate of bark sloughing from host trees and allelopathic effects may also control the local distribution of Spanish moss. Light and moisture appear to be less important factors. Thus, within a favorable climatic range, mineral and bark characteristics of host trees may be used to illustrate a niche hypervolume for this species.  相似文献   

10.
The levels of three essential minerals Ca, Fe and Mg and the extent of their availability were assessed in four commonly eaten Caribbean tuber crops [dasheen (Xanthosoma spp.), Irish potato (Solanum tuberosum), sweet potato (Ipomoea batatas) and yellow yam (Dioscorea cayenensis)] in their processed and unprocessed states. Calcium was highest in cooked dasheen (5150±50 mg/kg) while Magnesium was highest in uncooked Irish potato (3600±200 mg/kg). There was no significant loss of calcium from the food samples upon cooking. All the uncooked food samples displayed higher levels minerals assessed compared to the cooked samples except for cooked Irish potato that recorded the level of iron (182.25±8.75 mg/kg). Availability of these minerals in the cooked and uncooked tubers crops upon digestion also showed a similar pattern. In conclusion, the consumption of these tuber crops in the Caribbean may not be responsible for the reported cases of iron deficiency in the region. However, the␣availability of minerals from these tuber crops when consumed with other foods (the usual practice in the Caribbean) needs further investigation.  相似文献   

11.
I used novel quantitative measures to assess the impact of fruit seasonality on changes in diet and energy balance during 4918 hours of observation on <60 orangutans in Gunung Palung National Park, West Kalimantan, Indonesia, from September 1994 through September 1995. During this period a mast fruiting occurred, resulting in large fluctuations in fruit availability, measured by monitoring of 558 orangutan fruit trees. Orangutan diet varied tremendously in accordance with these fluctuations. During the month of highest fruit production, 100% of the orangutan diet was composed of fruit. In contrast, during the fruit-poor period as little as 21% of the diet was fruit, while 37% was bark. Nutritional analyses of 78 of the foods most commonly eaten during this study show that mast foods were significantly higher in caloric content than were nonmast foods, which translates into substantial changes in caloric intake. During the month of highest fruit consumption (January), males consumed an estimated 8422 kcal/day and females consumed 7404 kcal/day. During the month of lowest fruit consumption (May), males consumed 3824 kcal/day and females consumed 1793 kcal/day. These differences were significantly different between the 2 months for both males and females. In May, males ate significantly more kcal/day than females did. Time spent feeding did not differ between the two periods for either males or females. I assessed the impact of these changes in diet and caloric intake on orangutan physiological functioning by measuring ketones in 257 urine samples collected from adult males and females. Ketones—products of fat metabolism—were present in urine only during the fruit-poor period. These data suggest that orangutans are highly efficient at storing fat during fruit-rich periods and utilizing the reserves during times of fruit shortfall. This response may have important implications for orangutan survivorship, reproduction, and behavior.  相似文献   

12.
The natural history of the model yeast Saccharomyces cerevisiae is poorly understood and confounded by domestication. In nature, S. cerevisiae and its undomesticated relative S. paradoxus are usually found on the bark of oak trees, a habitat very different from wine or other human fermentations. It is unclear whether the oak trees are really the primary habitat for wild yeast, or whether this apparent association is due to biased sampling. We use culturing and high‐throughput environmental sequencing to show that S. paradoxus is a very rare member of the oak bark microbial community. We find that S. paradoxus can grow well on sterile medium made from oak bark, but that its growth is strongly suppressed when the other members of the community are present. We purified a set of twelve common fungal and bacterial species from the oak bark community and tested how each affected the growth of S. paradoxus in direct competition on oak bark medium at summer and winter temperatures, identifying both positive and negative interactions. One Pseudomonas species produces a diffusible toxin that suppresses S. paradoxus as effectively as either the whole set of twelve species together or the complete community present in nonsterilized oak medium. Conversely, one of the twelve species, Mucilaginibacter sp., had the opposite effect and promoted S. paradoxus growth at low temperatures. We conclude that, in its natural oak tree habitat, S. paradoxus is a rare species whose success depends on the much more abundant microbial species surrounding it.  相似文献   

13.
A multidisciplinary study of use by Sami people ofPinus sylvestris L. (Scots pine) inner bark was performed in northern Sweden. We combined linguistic, historical and archaeological records with ecological data collected from field studies to investigate important cultural and ecological factors associated with previous use of bark. Our data from bark peeled trees at 313 sites were used to describe patterns in space and time in the land-scape. Sites with bark peeled trees were mainly found in the central and northern part of Lapland (65°00–68°14N). Large numbers of barked trees were found in undisturbed forests in national parks and reserves but few were found in forests under commercial management. The dendroecological analysis revealed a continuous use of inner bark from A.D. 1450 to 1890. Large sheets of bark were taken from trees in the spring, prepared and stored as a staple food resource. Inner bark was eaten fresh, dried or roasted. Smaller bark peelings were used for the wrapping of sinews. The cessation of bark use in the 19th century was driven by several factors, but the availability of other products that could replace traditional use of bark was specifically important. The previous common and varied use of bark, the great age of Sami terminology and a possible association with archaeological remains of potential great age indicate that peeled bark was used long before the historic period. Our study also focused on the ongoing loss of culturally-modified trees in forests outside protected areas.  相似文献   

14.
Soil mining and eating (geophagy) behavior of rhesus macaques (Macaca mulatta) on Cayo Santiago, Puerto Rico, is described and assessed with respect to the chemical, geochemical, and mineralogical composition of the ingested materials. The samples forming the uneaten (control) and eaten (matrix and blocky) groups of soils come from the top and flanks of a marine terrace underlain with volcanic tuff on Cayo Santiago, off the east shore of Puerto Rico. Both the uneaten and geophagy samples were analyzed to determine particle size distributions, clay and primary mineralogy, and soil chemical and geochemical compositions. Primary minerals such as orthoclase and plagioclase feldspar in the clay fraction is higher in the control group than in the ingested samples. Both the control and matrix plus blocky samples have moderate to abundant amounts of kaolinite and halloysite (both silicon:aluminum = 1:1 type clay minerals) that may be important as a stimulus to geophagy behavior. The pH, total salts, and phosphorus levels in both the control and geophagy samples show considerable overlap with little clear indication of causal factors. Analysis of the geochemical data showed no clear cut elemental differences to suggest elemental supplementation as a possible explanation for mining and eating of tropical soil. It is possible that rhesus macaques ingest clay to obtain kaolinite/halloysite minerals which may alter the taste of their provided food, and may act as pharmaceutical agents to alleviate intestinal ailments such as diarrhea.  相似文献   

15.
The composition of the diet of a savanna-living population of wild chimpanzees (Pan troglodytes verus) at Mt. Assirik in Senegal is presented. The study site had a prolonged dry season, high temperatures, and vegetation dominated by grasses. Data came from direct observation, fecal specimens, and feeding traces; thus, strict criteria for acceptance of the indirect data were specified. Composition of diet was given in terms of species and family of prey, parts eaten, life-form, type of habitat, and criteria for inclusion. Forty-three species of plants with 60 parts were eaten; mostly fruits, from trees, in woodland. Nine species of animal prey were eaten, mostly social insects. An additional 41 species of plants with 53 parts were classed as likely to be eaten by chimpanzees, mostly on the grounds of their being eaten by sympatric anthropoids. Overall, the diet of the apes at Mt. Assirik resembles that of this species elsewhere in Africa, but the size of the dietary repertoire seems small and the proportion of low-quality foodstuffs high. The latter are mostly time-consuming to collect or tedious to obtain or process, and include underground storage organs.  相似文献   

16.
  • 1 The literature on bark‐stripping by red deer Cervus elaphus in Europe is reviewed to reveal quantitative variation in this behaviour and relate it to deer density and local characteristics such as dominant tree species, occurrence of artificial feeding, altitude, region and size of the study site. We also review the importance of bark in red deer diets over the seasons and discuss the causes of bark‐stripping, focusing on the significance of bark as food.
  • 2 Over the 36 sites examined, the rate of bark‐stripping was highly variable (from 0 to 84% of susceptible trees debarked), with less damage in Scotland than in other European sites for which bark‐stripping rates were higher at high red deer density. Altitude, the size of the study site, the number of dominant tree species and the occurrence of artificial feeding do not significantly relate to the rate of bark‐stripping.
  • 3 Bark sometimes made up a large proportion of red deer diet (> 10%), especially in areas with severe winters (high levels of snow), whereas in study sites with mild winters, bark was practically not eaten at all.
  • 4 These results suggest that severe bark‐stripping could be related to a reduction in food resource availability. This food availability hypothesis needs to be better documented, dealing particularly with the possible interaction between food availability and red deer density.
  相似文献   

17.
Abstract 1 When searching for suitable hosts in flight, especially in mixed forests, conifer‐inhabiting bark beetles will encounter not only suitable host trees and their odours, but also unsuitable hosts and nonhost trees. Rejection of these trees could be based on an imbalance of certain host characteristics and/or a negative response to some nonhost stimuli, such as nonhost volatiles (NHV). 2 Recent electrophysiological and behavioural studies clearly indicate that conifer‐inhabiting bark beetles are not only able to recognize, but also to avoid, nonhost habitats or trees by olfactory means. Green leaf volatiles (GLV), especially C6‐alcohols, from the leaves (and partly from bark) of nonhost angiosperm trees, may represent nonhost odour signals at the habitat level. Specific bark volatiles such as trans‐conophthorin, C8‐alcohols, and some aromatic compounds, may indicate nonhosts at the tree species level. Flying bark beetles are also capable of determining whether a possible host is unsuitable by reacting to signals from conspecifics or sympatric heterospecifics that indicate old or colonized host tree individuals. 3 Combined NHV signals in blends showed both redundancy and synergism in their inhibitory effects. The coexistence of redundancy and synergism in negative NHV signals may indicate different functional levels (nonhost habitats, species, and unsuitable hosts) in the host selection process. Combinations of NHV and verbenone significantly reduced the number of mass attacked host trees or logs on several economically important species (e.g. Dendroctonus ponderosae, Ips typographus, and I. sexdentatus). 4 We suggest a semiochemical‐diversity hypothesis, based on the inhibition by NHV of bark beetle host‐location, which might partly explain the lower outbreak rates of forest insects in mixed forests. This ‘semiochemical‐diversity hypothesis’ would provide new support to the general ‘stability‐diversity hypothesis’. 5 Natural selection appears to have caused conifer‐inhabiting bark beetles to evolve several olfactory mechanisms for finding their hosts and avoiding unsuitable hosts and nonhost species. NHV and unsuitable host signals have potential for use in protecting trees from attack. The use of these signals may be facilitated by the fact that their combination has an active inhibition radius of several metres in trap test, and by the observation of area effects for several trees near inhibitor soruces in tree protection experiments. Furthermore, incorporation of negative signals (such as NHV and verbenone) and pheromone‐based mass‐trapping in a ‘push–pull’ fashion may significantly increase the options for control against outbreaks of conifer‐inhabiting bark beetles, especially in high risk areas.  相似文献   

18.
Plants can form an immunological memory known as defense priming, whereby exposure to a priming stimulus enables quicker or stronger response to subsequent attack by pests and pathogens. Such priming of inducible defenses provides increased protection and reduces allocation costs of defense. Defense priming has been widely studied for short-lived model plants such as Arabidopsis, but little is known about this phenomenon in long-lived plants like spruce. We compared the effects of pretreatment with sublethal fungal inoculations or application of the phytohormone methyl jasmonate (MeJA) on the resistance of 48-year-old Norway spruce (Picea abies) trees to mass attack by a tree-killing bark beetle beginning 35 days later. Bark beetles heavily infested and killed untreated trees but largely avoided fungus-inoculated trees and MeJA-treated trees. Quantification of defensive terpenes at the time of bark beetle attack showed fungal inoculation induced 91-fold higher terpene concentrations compared with untreated trees, whereas application of MeJA did not significantly increase terpenes. These results indicate that resistance in fungus-inoculated trees is a result of direct induction of defenses, whereas resistance in MeJA-treated trees is due to defense priming. This work extends our knowledge of defense priming from model plants to an ecologically important tree species.  相似文献   

19.
We previously reported on a study of 4 soils that chimpanzees of the Kanyawara community in the Kibale National Park, Uganda consumed on a near-daily basis. We suggested that iron was a possible chemical stimulus in association with high quantities of Si:Al = 1:1-dominated clay minerals in the consumed material. To test our initial findings, we analyzed 18 samples from the same general area including 7 samples that the chimpanzees did not eat. Among the chemical elements, As, Au, Br, Ca, Cl, Dy, Mg, Ni, Sb, Sr, and I are below detection limits. Only Fe stands out as a potentially important nutritional element present in sufficient quantity to provide a physiological stimulus for chimpanzees living at high elevations near the flanks of the Ruwenzori Mountains. Along with Fe, metahalloysite is present in high amounts in these soils. In its pure crystalline form as a pharmaceutical grade clay mineral metahalloysite may well counteract the debilitating effects of diarrhea, with an effect similar to what is achieved with kaolinite (cf. KaopectateTM). An unexpected result, the relatively high nitrogen and carbon in the eaten samples relative to the uneaten group, indicates the chimpanzees may have a higher threshold for organic-rich material than previously believed. Contrarily, the color of the ingested material, depicts a material with less humus than in the uneaten group, a finding that is compatible with previous work reported at other geophagy sites in Africa. Of all the choices of soil available to them, the chimpanzees appear to be selecting highly homogeneous chemical natural earths with well-leached and uniform mineralogical material similar to the uneaten group, but with higher relative amounts of clay size material.  相似文献   

20.
The African savannah elephant (Loxodonta africana Blumenbach) is a generalist herbivore that relies on widely distributed resources. Vegetation decline, aggravated by these elephants, can compromise local conservation efforts. Thus it imperative to understand the factors that drive them to consume specific plant species and plant parts. The objective of our study was to investigate the feeding patterns of African savannah elephants in the enclosed bushveld savannah at the Atherstone Collaborative Nature Reserve in South Africa. For 1 year, we examined elephant selection of woody versus herbaceous vegetation, and identified which plant species and parts were preferentially consumed. We accomplished this by directly observing feeding elephants, and by utilizing data collected on elephant footprints, dung piles, stripped bark and broken branches. We further conducted vegetation surveys to determine selection frequency relative to species abundance. Elephants showed a preference for different plant parts consumption in the feeding plots. In total, leaves, branches and bark contributed mostly to their diet. Seasonal selection patterns showed an increasing proportion of bark and branch consumption during the dry season.  相似文献   

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