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1.
Two bird species, Leucopternis polionota and Dendrocincla fuliginosa , frequently follow coatis ( Nasua nasua) while they forage in the Atlantic forest of southeastern Brazil. Two other avian species, Trogon rufus and Habia rubica , have also been observed following coatis. This "following foraging behavior" is more frequent during the dry season when coatis forage in trees. For the birds, this can represent a coping strategy with the reduced resource availability during the drier season.  相似文献   

2.
ABSTRACT.   Prescribed burning is essential for maintaining suitable habitat for Bachman's Sparrows ( Aimophila aestivalis ), but burns conducted during the breeding season may lead to site abandonment and low survival or productivity. We monitored a color-banded population of Bachman's Sparrow in Georgia for four breeding seasons to assess home range size, site fidelity, and survival in an area managed primarily using breeding season burns. Our study area was one of the last remaining tracts of old-growth longleaf pine ( Pinus palustris ), and alternating halves of the tract were burned during the breeding season during each year of our study. Mean home range size for males ( N = 46) during the breeding season was 3.1 ha based on 95% fixed kernel analysis and 1.8 ha based on minimum convex polygons. Breeding season burning had no effect on male site fidelity and home range characteristics. The proportion of males remaining on burned areas was similar to the proportion remaining on unburned areas. Shifts in home range centroids pre- and postburn were also similar for males on unburned (median = 49.7 m) and burned (median = 65.6 m) areas. In addition, the size of home ranges that were burned ( ha) was similar to that of home ranges that were not burned ( ha). Estimated annual survival for males was 0.59. The median shift in annual home range centers calculated for 38 males observed during multiple breeding seasons was 63 m and, coupled with our survival estimates, suggest greater site fidelity than previously reported. These results suggest that breeding season burns were not as detrimental to Bachman's Sparrows as reported at other locations, and such burns may be helpful in maintaining suitable habitat.  相似文献   

3.
One of the most common types of polyspecific association observed in Neotropical primate communities is that between squirrel monkeys (Saimiri) and capuchins (Cebus). The present study focused on association patterns in two Saimiri sciureus groups in eastern Brazilian Amazonia, between March and October, 2009. The associations were analyzed in terms of the species involved, the degree of association, and niche breadth and overlap. The study involved two S. sciureus groups (B4 and GI) on the right and left bank of the Tocantins River, respectively, within the area of the Tucuruí reservoir in southeastern Pará. Relations between species were classified as associations (individuals within 50 m and moving in the same direction), and encounters (individuals within 50 m and no coordinated movement). Group B4 was in association with Cebus apella during 100% of monitoring, and with Chiropotes satanas in 20.2%. By contrast, Group GI associated with Cebus 54.8% of the time, and with Chiropotes utahickae 2.5%. Encounters with Alouatta belzebul and Saguinus niger were recorded at both sites, with Aotus azarae and Dasyprocta prymnolopha at B4, and with Callicebus moloch, Dasyproct aleporina, Mazama gouazoubira, and Nasua nasua at GI. Overall, Saimiri had a broader niche than Cebus in terms of vertical spacing and diet, but not for substrate use. This pattern did not appear to be affected by association. While group GI spent significantly (P < 0.05) more time in association with Cebus during the wet season, group B4 associated with Chiropotes more during the dry season. Despite the higher association rates, niche overlap was greater for all variables at B4. This may reflect differences in the ranging and foraging patterns at the two sites, and the varying potential benefits of association for Saimiri.  相似文献   

4.
Primate home range size and habitat use are affected by resource availability, which may change seasonally. Limestone langurs (Trachypithecus genus), including the Critically Endangered Cat Ba langur (Trachypithecus poliocephalus), live on limestone karst hills with shrubby and discontinuous vegetation. This study explores home range size and habitat use in relation to substrate, vegetation coverage, and hill type for Cat Ba langurs living on Cat Ba Island. We predicted that home range size would be similar to that of other limestone langurs and that as resources vary seasonally and across habitat types, habitat use would vary with season and behavior, with foraging concentrated on slopes, where food is plentiful. We collected 180 days of observational data on two reproductive groups (N?=?7 and N?=?10–13), taking GPS fixes of the group whenever they moved farther than the typical group spread to determine home ranges, and 10-min instantaneous scans to assess habitat use. The two groups had home ranges of 22 ha and 50 ha (0.32 and 0.20–0.26 individuals/ha respectively). Ranges for both groups were smaller in the dry season than the wet season, although we could not assess seasonal variation statistically. The langurs spent most scans on rocks, in sparsely vegetated areas, and on exposed slopes and steep cliffs; however they foraged primarily on gradually inclined slopes, especially in the dry season. These results suggest that conservation efforts should focus on protecting nutritionally important valleys and exposed slopes to ensure year-long access to food resources. It may, however, be difficult to balance human and nonhuman primate habitat use.  相似文献   

5.
Chestnut short-tailed bats, Carollia castanea , and Seba's short-tailed bats, C. perspicillata (Phyllostomidae), were radio-tracked ( N = 1593 positions) in lowland rain forest at Tiputini Biodiversity Station, Orellana Province, Ecuador. For 11 C . castanea , mean home range was 6.8 ± 2.2 ha, mean core-use area was 1.7 ± 0.8 ha, and mean long axis across home range was 438 ± 106 m. For three C . perspicillata , mean home range was 5.5 ± 1.7 ha, mean core-use area was 1.3 ± 0.6 ha, and mean long axis was 493 ± 172 m. Groups of less than five C. castanea occupied day-roosts in earthen cavities that undercut banks the Tiputini River. Carollia perspicillata used tree hollows and buildings as day-roosts. Interspecific and intraspecific overlap among short-tailed bats occurred in core-use areas associated with clumps of fruiting Piper hispidum (peppers ) and Cecropia sciadophylla . Piper hispidum seeds were present in 80 percent of the fecal samples from C . castanea and 56 percent of samples from C . perspicillata . Carollia perspicillata handled pepper fruits significantly faster than C . castanea ; however, C . castanea commenced foraging before C . perspicillata emerged from day-roosts. Evidence for exploitative competition between C . castanea and C . perspicillata is suggested by our observations that 95 percent of ripe P . hispidum fruits available at sunset disappear before sunrise ( N = 74 marked fruits). Piper hispidum plants produced zero to 12 ripe infructescences per plant each night during peak production. Few ripe infructescences of P . hispidum were available during the dry season; however, ripe infructescences of C . sciadophylla , remained abundant.  相似文献   

6.
We studied the foraging behaviour of Rhinolophus hipposideros on the island “Herrenchiemsee” in Lake Chiemsee (Upper Bavaria) during summer 2001. The island offers extensively managed woodlands, highly structured open landscapes and a broad reed belt around the shore. On average the flight activity of the 6 radio tracked females outside the roost lasted 229 min per night. The home range size varied between 6.8 and 62.7 ha (mean 25.2 ha). The size of the activity centres varied between 2.8 and 8.2 ha (mean 5.3) and all except one were located almost exclusively in woodland. Within woodlands the bats did not select for specific spatial structures (different age classes of the stands or canopy densities). Only two bats regularly foraged in additional habitats outside woodlands. One of these bats used orchards and tree rows; the other foraged over artificial ponds and gardens adjoining to its woodland foraging area. We never found the bats foraging over the lake or the reed belt. Longer linear landscape elements as tree lines were used during commuting flights but there was no indication of a continuous foraging activity along these elements. Two females left the island to forage on the mainland in August after the fledging of juveniles. To reach the mainland shore, the bats had to fly at least 1.2 km across the lake.

Assuming that most foraging flights on the island occur in woodlands, a bat density in this habitat type of 0.7 bats/ha can be calculated.  相似文献   


7.
The distribution of resources is a crucial determinant of animals' space use (e.g., daily travel distance, monthly home range size, and revisitation patterns). We examined how variation in ecological parameters affected variability in space use patterns of western lowland gorillas, Gorilla gorilla gorilla. They are an interesting species for investigating this topic because key components of their diet are nonfruit items (herbaceous vegetation and tree leaves) that occur at low density and are sparsely distributed, and fruits, which show high spatiotemporal variation in availability. We estimated how availability of nonfruit foods and fruit, frugivory (proportion of feeding time consuming fruit), and swamps in areas used by the gorillas influenced daily travel distance, monthly home range size, and revisit frequency to grid cells in the home range of one habituated gorilla group in Loango National Park, Gabon. Using location data from 2015 to 2018, we found that the gorillas decreased their daily travel distance as both the density of nonfruit foods and the proportion of swamps in areas used increased. Daily travel distances were shorter when both frugivory and availability of fruit were higher, yet, daily travel distances were longer when availability of fruit was low but frugivory was still high. Furthermore, monthly home range size increased as frugivory increased and monthly revisit frequencies to an area increased as fruit availability of an area increased. In conclusion, the availability of both nonfruit and fruit influenced the gorillas' space use patterns. Gorillas decreased foraging effort when food availability was high but were willing to incur increasing foraging costs to feed on fruit when availability was low. This study highlights how animals have to adjust their space use with changing resource availability and it emphasizes the value of examining multiple parameters of space use.  相似文献   

8.
In this paper we describe the use of space and feeding ecology of seven groups of golden lion tamarins observed for a total of 2,164 hr in Poço das Antas Reserve, Rio de Janeiro, Brazil. Relative to habitat availability in the home ranges of these groups, lion tamarins spent more time than expected in relatively undisturbed swamp forests and less time than expected in more degraded hillside and pasture habitats. Home range area was correlated with group biomass but not group size. Golden lion tamarins fed primarily on fruits and small animal prey, but relied heavily on floral nectar during seasonal periods of relatively low fruit availability. Compared to other New World monkeys, lion tamarins used larger home range areas and exhibited longer daily path lengths than would be predicted by group biomass alone. We suggest that this pattern of foraging and use of space may be explained by the relatively greater availability of cryptic prey and their microhabitats in forests that are flooded and/or have closed canopies than in forests that are in earlier stages of succession where prey may be more susceptible to desiccation during the dry season. Am. J. Primatol. 41:289–305, 1997. © 1997 Wiley-Liss, Inc.  相似文献   

9.
Many primates have to cope with a temporal scarcity in food availability that shapes their foraging strategies. Here we investigated the changes in diet, activity, and ranging behavior of a group of black-fronted titi monkeys (Callicebus nigrifrons) according to the availability of the main high-nutritional-density item in their diet and the foraging strategy adopted when this food is scarce. We monitored one habituated group using instantaneous scan sampling over 1 year (533 h of observation, 61 days) in a seasonal tropical forest fragment (245 ha). We simultaneously collected data on food availability with fruit traps. The titi monkeys consumed fleshy fruits, the main high-nutritional-density item of their diet, in accordance with its availability, and the availability of this item modulated the ingestion of vegetative plant parts, a relatively low-nutritional-density food. During high fleshy fruit availability, the titi monkeys consumed more fleshy fruits, flowers, and invertebrates. They also traveled more, but concentrated their activity in a central area of their home range. Conversely, during fleshy fruit scarcity, they increased the breadth of their diet, switching to one richer in seeds and vegetative plant parts, and with greater plant diversity. At the same time, they reduced most energy-demanding activities, traveling less and over shorter distances, but using their home range more broadly. Corroborating the optimal foraging theory, titi monkeys altered foraging strategies according to temporal food fluctuations and responded to low fleshy fruit availability by changing their diet, activity, and ranging behavior. The adoption of a low-cost/low-yield strategy allowed us to classify them as energy minimizers.  相似文献   

10.
A-503 contact-hr study of a 35-member group ofCebus albifrons was conducted in eastern Colombia in 1977 and 1978. The group had a female: male socionomic sex ratio of 2.5:1 and used a home range of 110–120 ha which overlapped the home range of another group ofC. albifrons about 20–30 ha. The animals spent about 80% of their foraging time eating plant material and about 20% of their foraging time eating animal materials. A birth peak at the end of the dry season extending into the wet season was indicated by data available. Attempted predation was recorded by the mustelidEira barbara and the black-and-white hawk-eagleSpizastur melanoleucus. Some association was observed with the red howler monkeyAlouatta seniculus. The group at times spent more than half the day foraging and traveling on the ground, exhibiting a level of terrestriality not reported for other New World primates.  相似文献   

11.
Tamarin activity patterns and habitat utilization strategies in the Tropical Dry Forest of the Panama Canal Zone were monitored quantitatively using radio-location telemetry. The daily tamarin activity pattern differed from that of other Neotropical primates in that early morning and late afternoon activity normally did not occur. Total daily activity time averaged 676 +/- 62 min. Sleeping trees, and behaviors associated with their use, were documented. Daily path length averaged 2,061 +/- 402 m. Mean travel distance was 468 +/- 66 m. Approximately one-third of the home range was utilized on a given day. Wet season home ranges for two social groups were 26 and 32 ha in area. Areas of low brush, forest edge, and vine-entangled second growth were heavily used by foraging tamarins. Large shade trees, particularly evergreens, were important as refuges from solar radiation. Open-canopy forest types and areas of grass were avoided. Social groups on resource-stable lowland sites defended territories; those on unstable upland sites used a system of time-space segregation. Upland groups became seminomadic during the dry season. Suitability of home range site may affect social group stability, natality, and infant survivorship.  相似文献   

12.
We investigated the ranging behaviour during the breeding season of 18 radiotracked little bustard (Tetrax tetrax) males, a disperse-lekking species inhabiting the cereal pseudo-steppes. The average kernel 95% home range was 60±50 ha and the average cluster 85% area was 17±17 ha. Range structure was as relevant as home range size for explaining the variation in the ranging behaviour of males, which could be partially explained by age, habitat quality and site. Ranging behaviour varied from males defending small and concentrated home ranges with high habitat quality, to males holding larger home ranges composed by several arenas. Our results suggest that social dominance and resource availability may affect ranging behaviour of males during the breeding season. Also, mating systems constraints may play a role on the use of space of males within the lekking ground. The ranging behaviour of a given male may be determined by a tendency to reduce and concentrate the home range as age and social status increase, and several fine-tuning mechanisms adjusting the ranging behaviour to the prevailing environmental or social factors on a given site and year.  相似文献   

13.
Abstract: For many wildlife species, agricultural landscapes undergo spatial and temporal fluctuations in the composition of food and cover annually with the planting and harvesting of crops. Raccoon (Procyon lotor) populations have flourished in agricultural landscapes, where crops increase foraging opportunities and efficiencies. However, information is lacking regarding the effects of temporal shifts in food and cover resulting from agricultural activities on raccoon home ranges. We examined home-range characteristics of 60 (33 M, 27 F) adult raccoons in northern Indiana, USA, from May 2003 through June 2005 to identify shifts in the size of home ranges and core use areas among seasons defined by crop availability and crop developmental stages. Mean fixed-kernel home-range (92 ± 6 ha; xM ± SE) and core-area sizes (20 ± 2 ha) of males were significantly larger than those of females (58 ± 7 ha and 13 ± 2 ha, respectively), and both were smaller than those reported for raccoons in other fragmented agricultural landscapes. Home-range sizes varied little among seasons for either sex. However, home ranges of males were smallest during the crop maturation stage, whereas home ranges of females were smallest during the crop growing season. The results of our study suggest that even in expansive rural landscapes, raccoons can maintain small home ranges when food, water, and denning resources are readily available. Additionally, the lack of differences among seasonal home-range sizes, despite the presence of an ephemeral superabundant food source (i.e., corn) during the maturation season, was likely due to the close proximity of foraging and denning resources across seasons.  相似文献   

14.
The home range behaviour and habitat selection by Red deer ( Cervus elaphus L. ) in a mixed-age Sitka spruce plantation was studied from1979–82 using radio-telemetry. Females used areas with rides, young replanted and pre-thicket crops, older stands where there were checked trees, more in proportion to availability than old closed-canopy stands, open-hill ground and high-elevation newly-established forest. They used open areas more at night, dusk and dawn, and the more secluded thickets during the day. Compared to females, young males were found more in older stands, high-altitude young plantation and on open-hill ground.
Home range size (406–1008 ha for females and1062–3059 ha for males) was smaller for animals with a high proportion of favourable habitats in their range, although larger range size did not incorporate a higher total area of favourable habitat. Individual ranges overlapped.
Females used the same range from season to season and from year to year. Intensity of range usage is discussed. Males dispersed a mean distance of 15 km from their area of capture during their first or second year of age. One young male used different areas each season after dispersal. Females centred their activity in the same river catchment from season to season, but male activity centres changed from one catchment to another.
Comparison is made with the results of studies of habitat selection in the same forest using dung-accumulation techniques, and with the ranging behaviour of Red deer on open-hill ground.  相似文献   

15.
The behavioural ecology of the Alpine marmot Marmota marmota (Linné, 1758) was studied Jun.—Sep. 1990 in the Vanoise National Park (French Alps). We describe the socio-spatial structure of a high-altitude population, to give additional information on the formerly unclear marmot social organization. The social unit was the family group, with a common home range between 0.9 and 2.8 ha; a slight overlapping occurred (9 to 12.5%). Each home range had a central area of main burrows, where the hibernaculum was located, and peripheral areas. Space utilization and distribution of activities during the season were analysed. Some activities took place exclusively in the centre area while peripheral parts were used for foraging. This latter increased in Aug. and decreased in Sep., marmots tending to remain more and more at the centre area as the hibernation period approached.  相似文献   

16.
A field study ofSaguinus nigricollis graellsi in the Cuyabeno Faunal Production Reserve, Ecuadorian Amazonia, established the characteristics of the home range and some reproductive aspects of the species. Field data were collected in two climatic seasons: dry, from December 1989 through March 1990, and rainy, from May through August 1990. Eight groups visited and/or lived in the study area during the dry season and ten during the rainy season. Group sizes ranged from two to nine individuals. Population density was estimated at 22–33 individuals per square km. The central group, which was followed intensively, had a home range which included both flooded and non-flooded forests. Terra firme forest was most used by the species. The home range of this group was reduced from 56.2 hectares (ha) in the dry season to 41.7 ha in the rainy season, probably as a result of a differential distribution of food plants between seasons. The presence of dense undergrowth where monkeys could hide to avoid predation and or a high concentration of food plants seem related to the preferential use of certain areas in the home range. The home ranges of neighboring groups overlapped considerably and peaceful temporary large groups were frequently observed. A generalized birth peak occurred in January 1990, dry season. In June 1990, rainy season, 40% of the groups exhibited a second birth peak. This reproductive bimodality of S. nigricollis graellsi indicates a high productivity of the forests at the Cuyabeno site. © 1995 Wiley-Liss, Inc.  相似文献   

17.
We studied home range and habitat selection of radio-marked adult California spotted owls (Strix occidentalis occidentalis) randomly selected from among the breeding population of owls in the central Sierra Nevada, California from June to October 2006. The most parsimonious home-range estimate for our data was 555 ha (SE = 100 ha). Home-range size was positively correlated with the number of vegetation patches in the home range (habitat heterogeneity). We used resource selection ratios to examine selection of vegetation types by owls within our study area. Owl home ranges contained a high proportion of mature conifer forest, relative to its availability, although the confidence interval for this estimate overlapped one. We also used resource selection functions (RSF) to examine owl foraging habitat selection. Relative probability of selection of foraging habitat was correlated with vegetation classes, patch size, and their interaction. Owls showed highest selection rates for large patches (>10 ha) of pole-sized coniferous forest. Our results suggested that spotted owls in the central Sierra Nevada used habitat that contained a high proportion of mature conifer forest at the home-range scale, but at a finer scale (foraging site selection) owls used other vegetation classes interspersed among mature forest patches, consistent with our hypothesis that spotted owls may use other forest types besides old growth and mature forests when foraging. Our study provides an unbiased estimate of habitat use by spotted owls in the central Sierra Nevada. Our results suggest that forest managers continue to protect remaining mature and old-growth forests in the central Sierra Nevada because owl home ranges contain high proportions of these habitats. However, our results also showed that owls used younger stands as foraging habitat so that landscape heterogeneity, with respect to cover types, may be an important consideration for management but we did not attempt to relate our findings to fitness of owls. Thus management for some level of landscape heterogeneity for the benefit of owls should proceed with caution or under an adaptive management framework. © 2011 The Wildlife Society.  相似文献   

18.
Habitat use by squirrel monkeys (Saimiri oerstedi) in Costa Rica   总被引:1,自引:0,他引:1  
This paper analyses movement patterns, habitat preferences, activity schedules, and dispersion of troop members in squirrel monkeys (Saimiri oerstedi) in relation to seasonal changes in food abundance in a Costa Rican tropical wet forest. Secondary forest was the preferred habitat and use of primary forest and late successional forest was limited primarily to seasons when food availability was low. Range area differed between seasons, varying from 79 to 110 ha, and totaling 176 ha over 11 months. The number of hectares used, hourly rate of group movement, and proportion of time spent foraging each season were all negatively related to relative food abundance. There was a tendency to spend less time in foraging activities in the middle of the day and to spend more time exclusively in travel at dawn and dusk. In all seasons dispersion was least when the troop was travelling and it was generally greatest during seasons of low food abundance. Measures of the allocation of time by the troop to food-related activities and the extent of troop dispersion each season were consistent with estimates based on behavior sampling of individuals.  相似文献   

19.
Little information exists on mixed-species groups between primates and other mammals in Neotropical forests. In this paper, we describe three such associations observed during an extensive large-vertebrate survey in central Amazonia, Brazil. Mixed-species groups between a primate species and another mammal were observed on seven occasions between squirrel monkeys (Saimiri cf. ustus) and either South American coatis (Nasua nasua) or tayras (Eira barbara) and between brown capuchins (Cebus apella) and coatis. All associations were restricted to floodplain forest during its dry stage. We suggest that the associations involving the coatis are connected to foraging and vigilance but may be induced by a common alternative food resource at a time of food shortage.  相似文献   

20.
Data on activity budgets and ranging patterns were collected from March to December 2001 for one group of François’ langurs (Trachypithecus francoisi) inhabiting a forested part of the Fusui Nature Reserve, Guangxi province, China. Our results indicate that the total size of the home range of the study group during the study period was 19 ha. The majority of their activities (52%) occurred within a small area, 22%, of their home range, and was concentrated in or near quadrats containing their sleeping sites, which may reduce the time and energetic cost of travel. The extent of the ranging behavior varied between months, with the smallest, 7 ha, recorded in July and the largest, 13.5 ha, in November. There was no significant difference between seasons. The monthly mean daily path lengths varied from 341 to 577 m. The daily path lengths showed significant seasonal changes: the path lengths were longer during the dry season than in the rainy season, which may be related to the scarcity of preferred food resources during the dry season.  相似文献   

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