Travel and Spatial Patterns Change When <Emphasis Type="Italic">Chiropotes satanas chiropotes</Emphasis> Inhabit Forest Fragments

Previous studies have used home range size to predict a species’ vulnerability to forest fragmentation. Northern bearded saki monkeys (Chiropotes satanas chiropotes) are medium-bodied frugivores with large home ranges, but sometimes they reside in forest fragments that are smaller than the species’ characteristic home range size. Here we examine how travel and spatial patterns differ among groups living in forest fragments of 3 size classes (1 ha, 10 ha, and 100 ha) versus continuous forest. We collected data in 6 research cycles from July–August 2003 and January 2005–June 2006 at the Biological Dynamics of Forest Fragments Project (BDFFP), north of Manaus, Brazil. For each cycle, we followed the monkeys at each study site from dawn until dusk for 3 consecutive days, and recorded their location. Although bearded saki monkeys living in 10-ha and 1-ha fragments had smaller day ranges and traveled shorter daily distances, they traveled greater distances than expected based on the size of the forest fragment. Monkeys in the small fragments revisited a greater percentage of feeding trees each day, traveled in more circular patterns, and used the fragments in a more uniform pattern than monkeys in the continuous forest. Our results suggest that monkeys in the small fragments maximize their use of the forest, and that the preservation of large tracts of forest is essential for species conservation. Species with large home ranges sometimes inhabit forest fragments, but doing so can alter behavior, demographics, and ecology, and the monkeys may be vulnerable to stochastic events.     

Behavior patterns of southern bearded sakis (Chiropotes satanas) in the fragmented landscape of eastern Brazilian Amazonia

The endangered but poorly studied southern bearded saki, Chiropotes satanas, faces extremes of habitat fragmentation throughout its geographic range in eastern Amazonia. This article focuses on the behavior of the members of two groups--a large one (30-34 members) in continuous forest (home range=69 ha) and a much smaller one (7 members) on a 17-ha man-made island--at the Tucuruí Reservoir on the Tocantins River. Quantitative behavioral data were collected through scan and all-events sampling. Both groups were characterized by the fission-fusion pattern of social organization typical of the genus and relatively high rates of traveling and feeding, also characteristic of the genus. However, the island group spent significantly more time resting and significantly less traveling than the mainland group, presumably as a function of its much smaller home range. Despite resting more, island group members engaged in significantly less social interaction, possibly because of the much smaller size of this group (which also affected visibility), or other factors, such as nutritional stress. Affiliative associations of males were a mainstay of social behavior in both groups and interspecific associations with capuchins (Cebus apella) and squirrel monkeys (Saimiri sciureus) were relatively common, especially in the mainland group. Overall, the island group presented a relatively reduced behavioral repertoire, apparently reflecting factors such as group size and the size and quality of its home range.     

The Ranging Costs of a Fallback Food: Liana Consumption Supplements Diet but Increases Foraging Effort in Howler Monkeys

Lianas are important components in the dynamics of tropical forests and represent fallback foods for some primates, yet little is known about their impact on primate ecology, behavior or fitness. Using 2 yr of field data, we investigated liana consumption and foraging effort in four groups of howler monkeys (two in bigger, more conserved forest fragments and two in smaller, less conserved fragments) to assess whether howler monkeys use lianas when and where food availability is scarce, and how liana consumption is related to foraging effort. Howler monkeys in smaller fragments spent more time consuming lianas and liana consumption was negatively related to the consumption of preferred food resources (fruit and Ficus spp.). Further, travel time was positively related to liana feeding time, but not to tree feeding time, and howler monkeys visited a greater number of food patches when feeding from liana leaves than when feeding from tree leaves. Our results suggest that these increases in foraging effort were related to the fact that lianas are mainly a source of leaves, and that liana patch size was probably smaller than tree patch size. While these results were clear when analyzing all four groups combined, however, they were not always significant in each of the groups individually. We suggest that this may be related to the differences in group size, patch size and the availability of resources among groups. Further studies are necessary to assess whether these dietary and behavioral adjustments negatively impact on the fitness and conservation of primates in fragments.     

Habitat Selection and Use of Space by Bald-Faced Sakis (Pithecia irrorata) in Southwestern Amazonia: Lessons from a Multiyear, Multigroup Study

Population density and distribution in tropical forest vertebrates are directly linked to patterns of use of space relative to habitat structure and composition. To examine how forest type may explain the ranging behavior and high variance in group density observed within the geographic range of bald-faced saki monkeys (Pithecia irrorata), we monitored habitat use of 5 neighboring focal groups of this species in southwestern Amazonia over 3 yr. To test whether sakis are unflooded (terra firme) forest specialists, we compared home range (HR) use to the corresponding availability of 4 main forest types and quantified HR size and activity budgets as a function of forest type. HR size varied from 16 to 60 ha, and saki population density at this scale (12.5 ± 6.4 SD individuals/km²) was more closely related to forest type than to group size. Although sakis were not obligate habitat specialists, groups clearly avoided bamboo forest and preferred terra firme forest. Terra firme forests were associated with small HRs, intensive use, high HR overlap, and territorial defense, all of which suggest that saki densities will be higher in areas dominated by terra firme forest where large patches of bamboo (Guadua spp.) are absent. The increased desiccation and subsequent forest fires expected in this region from the combined impacts of climate change and human land use potentially threaten the long-term viability of old-growth terra firme forest specialists such as sakis. Regional-scale conservation efforts should ensure that extensive blocks of terra firme forest are protected in areas that remain relatively free of bamboo.     

Gis analysis of patch use and group cohesiveness of bearded sakis (chiropotes sagulatus) in the upper essequibo conservation concession,guyana

This study examines how northern bearded sakis (Chiropotes sagulatus) in Guyana adjust group cohesiveness according to the distribution and quality of food patches. I introduce a GIS based method for quantifying food patch quality and how it relates to bearded saki group spread and group size. While the concept of food patch is central to most models of primate socioecology, defining what constitutes a patch has been notoriously problematic in primate studies. In addition, researchers have struggled to quantify group spread and group cohesiveness. Advances in spatial analysis software in the last decade now allow primate researchers to better quantify these variables. Group spread in bearded sakis was not significantly greater in lower quality patches and sakis were not more spread out during feeding than during other activities. However, the study group was significantly less spread out during social behavior. Bearded saki group size was significantly correlated with both monthly fruit abundance and patch quality. In fact, mean daily patch quality explained ～40% of the variation in foraging party size. These results suggest that bearded sakis may rely on a highly fluid social structure to mitigate the effects of intragroup feeding competition while living in large groups. Sakis do not adjust group spread on a patch‐by‐patch basis but rather fission into smaller foraging parties when resources become scarce seasonally and patch quality is low. This study shows that GIS is a powerful tool for modeling the relationship between group cohesiveness and resource quality and distribution. Am J Phys Anthropol, 2013. © 2012 Wiley Periodicals, Inc.     

Ethogram and Natural History of Golden-backed Uakaris (<Emphasis Type="Italic">Cacajao melanocephalus</Emphasis>)

We present an ethogram for golden-backed uakaris (Cacajao melanocephalus), based on observations in the field and on a captive individual. We also provide additional observations on the ecology of the wild animals. We studied 3 free-living groups (maximum counts of 5, 15, and 26 individuals) during two wet-seasons (March–July 2007 and January–June 2008) in the flooded igapó forest of Jaú National Park, Amazonas, Brazil. The groups lived in close proximity but never mixed, because river channels separated them. Groups showed fission-fusion behavior, subgroup sizes varied within groups, and we observed 13 different subgroup compositions. The areas used by the groups were ca. 0.82, 2.35, and 2.45 km². We defined a total of 9 behavioral categories. In the wild, the amount of time allocated to the behaviors traveling and foraging/feeding differed between months, but we found no difference in the amount of time devoted to behavioral categories across 3 periods of the day, possibly as a result of the patchy and unpredictable distribution or availability of food patches. Further, the activity patterns varied among groups, perhaps as a reflection of the different group sizes and compositions and different range sizes. We recorded 34 feeding items for wild golden-backed uakaris between January and June 2008, mostly fruits and seeds. No significant variation in the number of different food types occurred across months. We recorded 6 primate species in the study areas. The uakaris neither mobbed nor fled from any other primate species, with the exception of white-fronted capuchin monkeys (Cebus albifrons). In addition, golden-backed uakaris sometimes fled when seeing giant otters (Pteroneura brasiliensis), perhaps indicating that the otters are potential predators of the monkeys. The ethogram and behavioral data provided here increase knowledge of the behavioral ecology of the elusive golden-backed uakari, and will facilitate future comparative studies.     

Genetic estimates of immigration and emigration rates in relation to population density and forest patch area in <Emphasis Type="Italic">Peromyscus leucopus</Emphasis>

An emerging pattern is that population densities of generalist rodents are higher in small compared to large forest patches in fragmented landscapes. We used genetically based measures of migration between patches to test two dispersal-based hypotheses for this negative density-area relationship: (1) emigration rates from small patches should be relatively lower compared to large patches (“inhibited dispersal hypothesis”), or (2) immigration rates should be higher into small than large patches (“immigration hypothesis”). Neither hypothesis was supported using data on dispersal inferred from eight microsatellite loci for 12 populations of Peromyscus leucopus in six small (1.3–2.7 ha) and six large (8–150 ha) forest patches. Emigration rates were not lower from and immigration rates were not higher into small than large patches. In fact, contrary to both hypotheses, emigration rates were higher from populations of P. leucopus in small compared to large patches. Based on a combination of genetic and field data, we speculate that higher reproduction in smaller patches resulted in higher densities which led to higher emigration rates from those patches. Rates of reproduction (presumably driven by better habitat conditions in smaller patches), rather than dispersal, seems to drive density differences in forest patches. We conclude that smaller forest patches within an agricultural matrix act as a source of individuals, and that migration rates are fairly high among forest patches regardless of size.     

Scramble Competition Among <Emphasis Type="Italic">Colobus vellerosus</Emphasis> at Boabeng-Fiema,Ghana

We investigated the occurrence of scramble competition among Colobus vellerosus at Boabeng-Fiema, Ghana. If scramble competition had an impact on feeding efficiency among females, we expected a positive relationship between group size and the proportion of time spent feeding, day journey length, or home range size assuming resource availability is similar among the groups compared. We collected focal data on the feeding behavior of adult females and males over 11 mo (September 2000–August 2001) on 2 study groups: WW (n = 31–33 individuals) and B (n = 8–16 individuals). We also collected ranging data on group movements at half-hour intervals. The large group (WW1) had a significantly longer day journey length than the small group (B1), and females in the large group spent a significantly greater proportion of time feeding in the wet season, a period of low food availability, which suggests it may be a bottleneck period when food resources are scarce and Colobus vellerosus is close to being energy limited. The proximity data suggested females may be able to reduce or adjust for competition by having fewer neighbors when they feed and by spreading out when in a larger group. However, we found no relationship between home range size and group size or that females spent a greater proportion of time feeding than adult males did. Our results highlight the need to factor in differences in food availability when investigating scramble competition. Though equivocal, our results suggest scramble competition occurs among Colobus vellerosus, leading us to suggest there was a match with the potential competitive regime, i.e., food distribution.     

Abnormal Pelage Color in an Isolated Population of <Emphasis Type="Italic">Alouatta guariba clamitans</Emphasis> Cabrera, 1940 in South Brazil

We located 4 brown howlers (1 adult male, 2 adult females, and 1 juvenile male) showing abnormally lighter pelage in 3 social groups comprising 5, 6, and 9 individuals in a 20 ha-forest fragment in the State of Rio Grande do Sul, Brazil. Two additional groups composed only of normally colored individuals also live in the fragment, which is isolated from nearby fragments by 267–1009 m. They were the only brown howlers with abnormal pelage color out of a total of 386 individuals belonging to 67 groups in 21 fragments in the 5876-ha study area. The isolation of the forest fragment, its high howler density (2.2 individuals⁄ha), and large group size (8.8 ± 2.4 individuals) may decrease the likelihood of successful immigration into the population, leading to an increased probability of inbreeding that may facilitate the expression of rare alleles.     

Population Density Estimates of the Critically Endangered Yellow-tailed Woolly Monkeys (<Emphasis Type="Italic">Oreonax flavicauda</Emphasis>) at La Esperanza,Northeastern Peru

The critically endangered yellow tailed woolly monkeys (Oreonax flavicauda, Humboldt 1812) are endemic to the cloud forests of northeastern Peru. We surveyed populations of Oreonax flavicauda in the Centro Poblado La Esperanza, Amazonas department between May 2008 and March 2009. We conducted census work in an area comprising disturbed primary cloud forest interspersed with pasture lying between 3 protected areas, all of which are known to contain populations of Oreonax flavicauda. We used standardized line transect methodology to census an area of ca. 700 ha. We also recorded group size and composition. We compared the results of transect width estimation, Krebs’ method, and an ad libitum total group count. We calculated individual densities of 8.27/km² and 9.26/km2, and group densities of 0.93/km² and 1.04/km2 using Krebs’ method and transect width estimation, respectively. Average group size was 8.9, with 1–3 adult males, 1–6 adult females, and 0–6 juveniles and infants. The results from our transect surveys coincided well with our estimated total group count. Our results are similar to those from previous studies, although differences in methodologies and site-specific environmental factors make comparison difficult, and suggest that Oreonax flavicauda is able to survive in disturbed habitat when hunting pressure is low.     

Home-range Use by a Large Horde of Wild <Emphasis Type="Italic">Mandrillus sphinx</Emphasis>

The predicted relationship between home-range size and group mass in primates developed by Clutton-Brock and Harvey (1977) has proved extremely robust in describing the use of space by most primate species. However, mandrills (Mandrillus sphinx) are now known to have an extreme group mass in the wild, far larger than that of the species used originally to generate that relationship, and so it was unknown whether this relationship would be robust for this species. We investigated the home-range size and use of a wild horde of ca. 700 mandrills in Lopé National Park, Gabon, using radiotelemetry. The total area the horde used over a 6-yr period [100% minimum convex polygon (MCP)] was 182 km², including 89 km² of suitable forest habitat. Mandrills used gallery forests and isolated forest fragments with high botanical diversity far more intensively that the continuous forest and completely avoided savanna and marsh. Peeled polygons and fixed kernel contours revealed multiple centres of use, with the horde spending more than half its time in <10% of the total documented range, typical of a frugivore using a patchy environment. Home-range size and internal structure varied considerably between years, but total home range fitted the predicted relationship between group mass and home range size, despite being an outlier to the dataset. We discuss the conservation implications of the species’ space requirements, in light of current pressures on land use in their range.     

The effect of roads on spider monkeys’ home range and mobility in a heterogeneous regenerating forest

Arboreal fauna living in tropical ecosystems may be particularly affected by roads given their dependency on forest cover and the high vulnerability of such ecosystems to changes. Over a period of 4 yr, we followed subgroups of spider monkeys living in a regenerating dry tropical forest with 8.2 km of roads within their home range. We aimed to understand whether roads shaped the home range of spider monkeys and which road features affected their movement. Only 18 percent (3 km) of the spider monkeys’ home range perimeter bordered with roads; these roads had greater habitat disparity between road sides than roads inside the home range. Although monkeys were reluctant to be close to roads, and roadside habitat contained low proportions of mature forest, spider monkeys crossed roads at 69 locations (7.5 crossings per kilometer). The main road characteristic affecting crossings was canopy opening size, with greater probability of crossing where canopy openings were smaller. Our findings support the importance of canopy opening size for road crossing of arboreal taxa, but they also indicate the relevant role roadside forest structure may have. Minimizing canopy opening size and forest disturbance along roads can facilitate the movement of arboreal fauna and preserve the important role of spider monkeys and other arboreal taxa in seed dispersal and thus the maintenance and regeneration of forest diversity.     

Effects of Seasonal Folivory and Frugivory on Ranging Patterns in <Emphasis Type="Italic">Rhinopithecus roxellana</Emphasis>

The distribution of food resources in time and space may affect the diet, ranging pattern, and social organization of primates. We studied variation in ranging patterns in a group of Sichuan snub-nosed monkeys (Rhinopithecus roxellana) over winter and summer in response to variation in their diet in the Qingmuchuan Nature Reserve, China. There was a clear diet shift from highly folivorous in winter to highly frugivorous in summer. The home range was 8.09 km² in summer and 7.43 km² in winter, calculated via the 95% kernel method. Corresponding to the diet shift, the focal group traveled significantly longer distances in summer (mean 1020 ± 69 m/d) than in winter (mean 676 ± 53 m/d); the daily range was also significantly greater in summer (mean 0.27 ± 0.02 km²/d) than in winter (mean 0.21 ± 0.01 km²/d). There was no significant variation in home range size between winter and summer, and the monkeys did not use geographically distinct ranges in summer and winter. However, overlap in the actual activity area and core range between winter and summer was only 0.13 km², representing 4.4% of the summer core area and 5.3% of the winter core area. Differences were apparent between summer and winter ranging patterns: In summer, the group traveled repeatedly and uninterruptedly across its home range and made 3 circles of movement along a fixed route in 31 d; in winter, the activity area was composed of 3 disconnected patches, and the focal group stayed in each patch for an average of 8 successive days without traveling among patches. Winter range use was concentrated on mixed evergreen and deciduous forest patches where leaves and fruits were available, whereas the summer range pattern correlates significantly positively with the distribution of giant dogwood (Cornus controversa) fruits. Thus it appears that the diet shift of Sichuan snub-nosed monkeys between winter and summer caused the monkeys to use their home range in different ways, supporting the hypothesis that food resources determine primate ranging patterns.     

Effect of Forest Fragmentation on Tick Infestations of Birds and Tick Infection Rates by Rickettsia in the Atlantic Forest of Brazil

Habitat loss and modifications affect biodiversity, potentially contributing to outbreaks of infectious diseases. We evaluated if the patch sizeinfragmented areas of Atlantic Forest in southeastern Brazil influences the diversity of forest birds and consequently the prevalence of ticks on birds and the rickettsial infection of these ticks. During 2 years, we collected ticks from birds in 12 sites: four small forest patches (80–140 ha), four large ones (480–1,850 ha), and four forest control areas within the much larger Morro do Diabo State Park (~36,000 ha). A total of 1,725 birds were captured (81 species, 24 families), from which 223 birds were infested by 2,339 ticks of the genus Amblyomma, mostly by the species A. nodosum. Bird diversity and richness were higher in larger than smaller forest fragments. The prevalence of ticks on birds was inversely correlated with bird diversity and richness. Among 174 A. nodosum tested for rickettsial infection by polymerase chain reaction, 51 were found to be infected by Rickettsia bellii or Rickettsia parkeri. However, tick infection rates by Rickettsia spp. were not statistically different between forest patch sizes. The higher prevalence of ticks on birds in degraded patches might be caused by a dominance of a few generalist bird species in small patches, allowing an easier transmission of parasites among individuals. It could also be related to more favorable microclimatic conditions for the free-living stages of A. nodosum in smaller forest fragments.The higher burden of ticks on birds in smaller forest fragments is an important secondary effect of habitat fragmentation, possibly increasing the likelihood of Rickettsia contagion.     

Reinvasion by ship rats (<Emphasis Type="Italic">Rattus rattus</Emphasis>) of forest fragments after eradication

Reinvasions provide prime examples of source-sink population dynamics, and are a major reason for failure of eradications of invasive rats from protected areas. Yet little is known about the origins and population structure of the replacement population compared with the original one. We eradicated eight populations of ship rats from separate podocarp-broadleaved forest fragments surrounded by open grassland (averaging 5.3 ha, scattered across 20,000 ha) in rural landscapes of Waikato, New Zealand, and monitored the- re-establishment of new populations. Rats were kill-trapped to extinction during January to April 2008, and then again after reinvasion in April–May (total n = 517). Rats carrying Rhodamine B dye (n = 94), available only in baits placed 1–2 months in advance in adjacent source areas located 170–380 m (average 228 m edge to edge) away, appeared in 7 of the 8 fragments from the first day of the first eradication. The distribution of age groups, genders and proportions of reproductively mature adults (more immature juvenile males and fewer fully mature old females) was different among marked rats compared with all other rats (P = 0.001, n = 509); in all rats caught on days 7+ of the first eradication compared with on days 1–6 (P = 0.000); and in the total sample collected in fragments by trapping to and after local extinction compared with in brief, fixed-schedule sampling of populations in continuous forests (P = 0.000). Genotyping of 493 carcases found no significant population-level differentiation among the 8 fragments, confirming that the rats in all fragments belonged to a single dynamic metapopulation. Marked rats of both genders travelled up to 600 m in a few days. Conservation of forest fragments is compromised by the problem that ship rats cannot be prevented from rapidly reinvading any cleared area after eradication.     

Ranging of <Emphasis Type="Italic">Rhinopithecus bieti</Emphasis> in the Samage Forest,China. I. Characteristics of Range Use

We quantified the home range and explored the style of ranging of black-and-white snub-nosed monkeys (Rhinopithecus bieti) in the subtropical-temperate montane Samage Forest (part of Baimaxueshan Nature Reserve) in the vicinity of Gehuaqing. Over 14.5 mo, we took positional records of the study band via a GPS receiver at 30-min intervals, and found that they covered an area of 32 km². Over a 10-yr period, the group even ranged in an area of 56 km², which is among the largest home range estimates for any primate. The large home range was probably due to the combined effects of large group size (N > 400) and forest heterogeneity, with seasonally food-rich areas interspersed with less valuable areas. The subjects did not use their home range uniformly: 29% of the grid cells had more location records than expected based on a uniform distribution, thus representing a core area, albeit a disjunct one. A continuous 1-mo group follow in the fall revealed that the band traveled on average 1.62 km/d and that days of concentrated use of a particular forest block were followed by more extensive marches. Neither climate nor human disturbance parameters correlate significantly with monthly estimates of the group’s home range size. Even though there is no significant correlation between temporal availability of plant phenophases and range size, our observations implicate temporal and spatial availability of food as a determinant of home range use of the focal group. Winter, spring, and summer home ranges are equally large: 18.2, 17.8, and 18.6 km², respectively. Home range decreased markedly in fall (9.3 km²), probably because the band obtained sufficient food resources (fruit) in a smaller area. The large winter range is best attributed to the exploitation of dispersed clumped patches of mature fruits. Cyril C. Grueter and∙Dayong Li contributed equally to the paper.     

Activity rhythms and use of space of a group ofAotus azarae in Bolivia during the rainy season

A group ofAotus azarae living in an island forest in the Beni region of Bolivia was observed for ten nights during the rainy season of 1985. The three members of the group, an adult male, an adult female, and the young of the year, spent 49.4% of their time resting, 31.7% feeding and 19.8% locomoting. Activity started with low intensity vocalizations about 10–15 min after sunset, the animals returning to the sleeping site in the morning, 10 to 20 min before dawn. Feeding occurred mainly during the early hours of the night, and from 1:30 a.m. to 4:00 a.m. they spent most of their time at rest. The average distance travelled per night was 337.4 m, the monkeys locomoting mainly in the first half of the night. Of the whole of the island forest (0.33 ha), our monkeys used mainly an area of 0.18 ha.     

Diet,Activity Patterns,and Ranging Ecology of the Bale Monkey (<Emphasis Type="BoldItalic">Chlorocebus djamdjamensis</Emphasis>) in Odobullu Forest,Ethiopia

Bale monkeys (Chlorocebus djamdjamensis) are little-known primates endemic to the forests of the Bale Massif and Hagere Selam regions of Ethiopia. From August 2007 to May 2008, we conducted the first ever study of the species’ behavior and ecology, focusing in particular on its diet, activity patterns, and ranging ecology in the Odobullu Forest. We studied 2 neighboring groups (group A: 55–60 members; group B: 46–50 members) and conducted behavioral scan samples on the first 2–5 individuals sighted at 15-min intervals. Feeding accounted for 65.7% of the activity budget, followed by moving (14.4%), resting (10.7%), social (7.1%), and other behaviors (2.4%). Overall diet during the study was dominated by young leaves (80.2%), though subjects also ate fruits (9.6%), flowers (3.1%), animal prey (2.3%), shoots (1.5%), stems (1.4%), mature leaves (1.1%), and roots (0.9%). Bale monkeys consumed only 11 plant species; of these, the top 5 species accounted for 94.3% of their diet. The top food item, bamboo (Arundinaria alpina), was responsible for a remarkable 76.7% of their diet, with most (95.2%) of the bamboo consumption consisting of young leaves. Mean daily path length for the study groups was 928 m and mean (100% minimum convex polygon) home range size was 15.2 ha. Though we are cautious in drawing conclusions from only 2 groups, the larger group traveled further per day and occupied a larger home range, patterns suggesting scramble competition may be occurring in Bale monkey groups at Odobullu. The dietary specialization of Bale monkeys on bamboo makes them unique among Chlorocebus spp. and suggests an intriguing ecological convergence with the golden monkeys (Cercopithecus mitis kandti) of Uganda and bamboo lemurs (Hapalemur spp.) of Madagascar. Their narrow ecological niche, limited geographic distribution, and bamboo harvesting by local people for commercial purposes place Bale monkeys at risk of extinction. To ensure the long-term survival of Bale monkeys, appropriate management action should be taken to conserve the species and the bamboo forests upon which it depends.     

The fine-scale utilization of forest edges by mammalian mesopredators related to patch size and conservation issues in Central European farmland

The marked negative impact of habitat fragmentation and the edge effect on many populations of bird species is a recent major concern in conservation biology. Here, we focus on the edge effect in different sized forest patches in Central European farmland. In particular, we tested whether the distribution of mammalian mesopredators is related to fragment size and distance to habitat edge, and whether the contribution of these factors is additive or interactive. To assess fine-scale utilization of forest edges, we established transects of four scent stations at different distances from forest edges into the interior (0, 25, 50, 100 m) in 146 forest fragments of variable patch size (3.2–5099.6 ha) from May to June, 2008–2009. This large sample size allowed us to perform detailed analyses separately for all detected species. Our findings confirm that mammalian mesopredators strongly prefer habitat edges and small forest fragments. The probability of occurrence tended to decrease with increasing distance from the edge for all seven carnivore species detected. The carnivores’ occurrence was also negatively correlated with forest fragment area. All detected species tended to prefer small fragments, with the exception of the Eurasian badger (showing the reverse but non-significant pattern) and the red fox (no effect of fragment size). In addition, the non-significant interaction between fragment size and distance to edge suggests that both of these factors contribute independently and additively to mesopredator-mediated effects on biota in a fragmented landscape.     

Differences in Diet Between Spider Monkey Groups Living in Forest Fragments and Continuous Forest in Mexico

Forest fragmentation can lead to reductions in food availability, especially for some large‐bodied tropical mammals such as spider monkeys. During a 15\xE2\x80\x90mo period, we assessed the diet of Geoffroyi's spider monkey (Ateles geoffroyi) in continuous forest and fragments in the Lacandona region, southern Mexico, and related differences in diet to differences in vegetation structure and composition. We found that both forest types presented top food species for monkeys (e.g., Spondias spp., Brosimum alicastrum), but the sum of the importance value index of these species and the density of large trees were lower in fragments than in continuous forest. We also found that, compared with continuous forest, monkeys in fragments diversified their overall diet, increased consumption of leaves, and reduced the time they spent feeding on trees in favor of more time feeding on hemiepiphytes (particularly Ficus spp.) and palms, both of which were common in fragments. We attribute these changes to the relative food scarcity of the most favored feeding plants in forest fragments. Overall, our findings suggest that monkeys are able to adjust their diet to food availability in fragments, and thus persist in small‐ and medium‐sized fragments. Although it is unlikely that the small size of two of the three study fragments (14 and 31 ha) can maintain viable populations of monkeys in the long term, they may function as stepping stones, facilitating inter‐fragment movements and ultimately enhancing seed dispersal in fragmented landscapes.