A global assessment of primate responses to landscape structure

Land‐use change modifies the spatial structure of terrestrial landscapes, potentially shaping the distribution, abundance and diversity of remaining species assemblages. Non‐human primates can be particularly vulnerable to landscape disturbances, but our understanding of this topic is far from complete. Here we reviewed all available studies on primates' responses to landscape structure. We found 34 studies of 71 primate species (24 genera and 10 families) that used a landscape approach. Most studies (82%) were from Neotropical forests, with howler monkeys being the most frequently studied taxon (56% of studies). All studies but one used a site‐landscape or a patch‐landscape study design, and frequently (34% of studies) measured landscape variables within a given radius from the edge of focal patches. Altogether, the 34 studies reported 188 responses to 17 landscape‐scale metrics. However, the majority of the studies (62%) quantified landscape predictors within a single spatial scale, potentially missing significant primate–landscape responses. To assess such responses accurately, landscape metrics need to be measured at the optimal scale, i.e. the spatial extent at which the primate–landscape relationship is strongest (so‐called ‘scale of effect’). Only 21% of studies calculated the scale of effect through multiscale approaches. Interestingly, the vast majority of studies that do not assess the scale of effect mainly reported null effects of landscape structure on primates, while most of the studies based on optimal scales found significant responses. These significant responses were primarily to landscape composition variables rather than landscape configuration variables. In particular, primates generally show positive responses to increasing forest cover, landscape quality indices and matrix permeability. By contrast, primates show weak responses to landscape configuration. In addition, half of the studies showing significant responses to landscape configuration metrics did not control for the effect of forest cover. As configuration metrics are often correlated with forest cover, this means that documented configuration effects may simply be driven by landscape‐scale forest loss. Our findings suggest that forest loss (not fragmentation) is a major threat to primates, and thus, preventing deforestation (e.g. through creation of reserves) and increasing forest cover through restoration is critically needed to mitigate the impact of land‐use change on our closest relatives. Increasing matrix functionality can also be critical, for instance by promoting anthropogenic land covers that are similar to primates' habitat.     

Conserving social-ecological systems in Indonesia: human-nonhuman primate interconnections in Bali and Sulawesi

An important question asked by primatologists and conservationists alike is: what is the relevance of primates and primate conservation for ecosystem conservation? The goal of this article is to contribute to this dialogue by advocating the use of a research perspective that focuses on the dynamics of human-nonhuman primate sympatry and interaction (i.e., ethnoprimatology) in order to better understand complex social-ecological systems and to inform their conservation management. This perspective/approach is based largely on the recognition that human primates are important components of all ecological systems and that niche construction is a fundamental feature of their adaptive success. To demonstrate the relevance of the human-nonhuman primate interface for ecosystem conservation, we provide examples from our research from two islands in the Indonesian archipelago: Bali and Sulawesi. In Bali, humans and long-tail macaques coexist in a system that creates favorable environments for the macaques. This anthropogenic landscape and the economic and ecological relationships between humans and monkeys on Bali provide insight into sustainable systems of human/nonhuman primate coexistence. In Lore Lindu National Park in Central Sulawesi, villagers and Tonkean macaques overlap in their use of both forest and cultivated resources. The finding that the Arenga pinnata palm is extremely important for both villagers and macaques points to a conservation management recommendation that may help protect the overall ecosystem; the cultivation and propagation of mutually important tree species at forest-agricultural ecotone as a means to curb crop raiding and to alleviate farmer's perceived need to clear additional forest.     

Giardia sp. and Cryptosporidium sp. infections in primates in fragmented and undisturbed forest in western Uganda

In June 2005, we collected 115 fecal samples from wild primates in western Uganda and examined them for Cryptosporidium sp. and Giardia sp. with the use of immunofluorescent antibody (IFA) detection. We sampled primates from an undisturbed forest in Kibale National Park and from 3 highly disturbed forest fragments outside the park. Of disturbed forest samples, red colobus (Pilocolobus tephrosceles) and red-tailed guenons (Cercopithecus ascanius) harbored species of Cryptosporidium or Giardia, but black-and-white colobus (Colobus guereza) did not. All primate samples from undisturbed forest were negative for both parasites. Seven of 35 (20%) red colobus and 1 of 20 red-tailed guenons (5%) from forest fragments were infected with either Cryptosporidium sp. or Giardia sp. The presence of Cryptosporidium and Giardia species in primates living in forest fragments, but not in primates in undisturbed forest, suggests that habitat disturbance may play a role in transmission or persistence of these pathogens.     

Primate Population Densities and Sizes in Atlantic Forest Remnants of Northern Espírito Santo,Brazil

We surveyed primates in seven fragments of Atlantic forest ranging from 210 to 24,250 ha in Espírito Santo, southeastern Brazil. The objective was to assess their population densities and fragment-specific population sizes in order to discuss the survival of primates in this highly fragmented landscape. We used line-transect sampling for censusing primates and estimated densities via DISTANCE program. Alouatta fusca, Cebus apella, Callicebus personatus, and Callithrix geoffroyi live in the study area. Although variable, primate numbers were higher in larger than in smaller fragments, the likely reasons being the lack of space and food resources (fruits) and higher impact of mesopredators (small cats) in small fragments. The estimated densities are within the range reported for other Atlantic forest sites, except for brown howlers (Alouatta fusca), which were extremely rare. Estimates of population sizes were on the order of several hundreds to thousands of individuals/species in the large-sized fragments (ca. 20,000 ha), while comparable estimates for the other areas indicate <500 individuals/species in the medium-sized reserves (ca. 2,000 ha), and <50 individuals/species in the small fragments (ca. 200 ha). These estimates suggest that only Atlantic forest fragments 20,000 ha can harbor primate populations large enough to escape extinction in the long term. Given that <20% of all protected areas remaining in the Atlantic forest are 20,000 ha, management measures are urgently needed to improve primate conservation in this biome.     

Status of diurnal primate populations at the former settlement of a displaced village in Cameroon

To understand whether or not primate populations recover in areas of abandoned human settlements, data are required that allow for site‐specific comparison over time. Here, we present baseline information on the presence/absence and relative abundance of primate species at the abandoned settlement of the Ekundukundu village, relocated out of the Korup National Park in 2000. Between July 2007 and March 2008, 62 km of transects was surveyed for sightings and calls of primates. All eight species of diurnal primates reported in the KNP were confirmed: Cercopithecus nictitans ludio, C. mona, C. erythrotis camerunensis, C. pogonias, Procolobus pennantii preussi, Cercocebus torquatus, Mandrillus leucophaeus leucophaeus, and Pan troglodytes vellerosus. At old Ekundukundu, C. nictitans accounted for 65% of all primate group sightings. Overall, sighting frequency of primates (0.55 groups/km) was not significantly different from other park sectors surveyed by a previous observer (J. Linder) in 2004–2005. The data reported here will be useful in the long‐term monitoring of primate populations in regenerating forest habitats of earlier human settlements. Am. J. Primatol. 72:645–652, 2010. © 2010 Wiley‐Liss, Inc.     

Molecular characterization of nodule worm in a community of Bornean primates

Strongyles are commonly reported parasites in studies of primate parasite biodiversity. Among them, nodule worm species are often overlooked as a serious concern despite having been observed to cause serious disease in nonhuman primates and humans. In this study, we investigated whether strongyles found in Bornean primates are the nodule worm Oesophagostomum spp., and to what extent these parasites are shared among members of the community. To test this, we propose two hypotheses that use the parasite genetic structure to infer transmission processes within the community. In the first scenario, the absence of parasite genetic substructuring would reflect high levels of parasite transmission among primate hosts, as primates’ home ranges overlap in the study area. In the second scenario, the presence of parasite substructuring would suggest cryptic diversity within the parasite genus and the existence of phylogenetic barriers to cross‐species transmission. By using molecular markers, we identify strongyles infecting this primate community as O. aculeatum, the only species of nodule worm currently known to infect Asian nonhuman primates. Furthermore, the little to no genetic substructuring supports a scenario with no phylogenetic barriers to transmission and where host movements across the landscape would enable gene flow between host populations. This work shows that the parasite's high adaptability could act as a buffer against local parasite extinctions. Surveys targeting human populations living in close proximity to nonhuman primates could help clarify whether this species of nodule worm presents the zoonotic potential found in the other two species infecting African nonhuman primates.     

呼中林区火烧点格局分析及影响因素

林火是森林生态系统景观格局、动态和生态过程的重要自然驱动力,理解林火发生空间格局与影响因素对于林火安全管理具有重要的作用。采用点格局分析方法,以黑龙江大兴安岭呼中林区1990-2005年火烧数据为研究案例,分析了火烧点空间格局及其影响因素。结果表明,火烧点在空间上的分布是不均匀的,呈现聚集分布,存在一些火烧高发区和低发区。呼中林区火烧概率是0.004-0.012次/(km² · a),平均火烧概率为0.0077次/(km² · a)。人类活动因子、地形因子和植被因子对林火的发生均具有重要作用。应用空间点格局分析方法表明,距离居民点和道路的距离、高程、坡度和林型是影响林火发生的显著因子。因此在进行森林防火管理时,仅仅通过控制人类活动对于降低林火火险的效果是有限的,地形和林型也是林火防控时重点要考虑的因素。     

High density of white-faced capuchins (Cebus capucinus) and habitat quality in the Taboga Forest of Costa Rica

Across the globe, primates are threatened by human activities. This is especially true for species found in tropical dry forests, which remain largely unprotected. Our ability to predict primate abundance in the face of human activity depends on different species' sensitivities as well as on the characteristics of the forest itself. We studied plant and primate distribution and abundance in the Taboga Forest, a 516-ha tropical dry forest surrounded by agricultural fields in northwestern Costa Rica. We found that the density of white-faced capuchins (Cebus capucinus) at Taboga is 2–6 times higher than reported for other long-term white-faced capuchin sites. Using plant transects, we also found relatively high species richness, diversity, and equitability compared with other tropical dry forests. Edge transects (i.e., within 100 m from the forest boundary) differed from interior transects in two ways: (a) tree species associated with dry forest succession were well-established in the edge and (b) canopy cover in the edge was maintained year-round, while the interior forest was deciduous. Sighting rates for capuchins were higher near water sources but did not vary between the edge and interior forest. For comparison, we also found the same to be true for the only other primate in the Taboga Forest, mantled howler monkeys (Alouatta palliata). Year-round access to water might explain why some primate species can flourish even alongside anthropogenic disturbance. Forest fragments like Taboga may support high densities of some species because they provide a mosaic of habitats and key resources that buffer adverse ecological conditions.     

Resource separation analysis with moose indicates threats to caribou in human altered landscapes

Species recovery is often impeded by inadequate knowledge on mechanisms of community interactions that cause and exacerbate species endangerment. Caribou and wild reindeer Rangifer tarandus are declining in many regions of their circumpolar range likely because of human‐induced landscape changes. In general, their niche specialization enables Rangifer to survive in nutrient‐poor habitats spatially separated from other ungulates and their shared predators. Research has indicated that shifts in primary prey distribution following human landscape alteration may result in spatial overlap with Rangifer. We studied overlap relationships of woodland caribou R. t. caribou and moose Alces alces, quantified by their differential use of environmental resources, and evaluated the role of human landscape alteration in spatial separation in south‐western Canada. Anthropogenic conversion of old‐growth forests to early seral stands is hypothesized to decrease the spatial separation between caribou and moose, the dominant prey for wolves Canis lupus, contributing to increased caribou mortality. Redundancy analysis (RDA) was first used to examine coarse scale resource separation across our study area. Second, at a finer spatial scale, we used logistic regression to compare resource‐ and spatial separation of sympatric pairs of 17 moose and 17 caribou. Finally, we tested if the frequency of predator‐caused caribou mortalities was higher in regions with higher moose resource use. Although environmental resource separation was strong at the coarser scale, we observed substantial spatial overlap (>50%) at the finer scale. In summer we reported a significant positive relationship between spatial overlap of moose and caribou and the degree of human landscape alteration. Most importantly, locations of caribou mortalities corresponded with areas of high resource use by moose in summer. Thus, consistent with the spatial separation hypothesis, our research suggests that early successional forest stages may decrease spatial separation between caribou and moose, resulting in increased mortality risk for threatened caribou.     

Nodular Worm Infections in Wild Non-human Primates and Humans Living in the Sebitoli Area (Kibale National Park,Uganda): Do High Spatial Proximity Favor Zoonotic Transmission?

Background

Nodular Oesophagostomum genus nematodes are a major public health concern in some African regions because they can be lethal to humans. Their relatively high prevalence in people has been described in Uganda recently. While non-human primates also harbor Oesophagostomum spp., the epidemiology of this oesophagostomosis and the role of these animals as reservoirs of the infection in Eastern Africa are not yet well documented.

Methodology/Principal Findings

The present study aimed to investigate Oesophagostomum infection in terms of parasite species diversity, prevalence and load in three non-human primates (Pan troglodytes, Papio anubis, Colobus guereza) and humans living in close proximity in a forested area of Sebitoli, Kibale National Park (KNP), Uganda. The molecular phylogenetic analyses provided the first evidence that humans living in the Sebitoli area harbored O. stephanostomum, a common species in free-ranging chimpanzees. Chimpanzees were also infected by O. bifurcum, a common species described in human populations throughout Africa. The recently described Oesophagostomum sp. found in colobine monkeys and humans and which was absent from baboons in the neighboring site of Kanyawara in KNP (10 km from Sebitoli), was only found in baboons. Microscopic analyses revealed that the infection prevalence and parasite load in chimpanzees were significantly lower in Kanyawara than in Sebitoli, an area more impacted by human activities at its borders.

Conclusions/Significance

Three different Oesophagostomum species circulate in humans and non-human primates in the Sebitoli area and our results confirm the presence of a new genotype of Oesophagostomum recently described in Uganda. The high spatiotemporal overlap between humans and chimpanzees in the studied area coupled with the high infection prevalence among chimpanzees represent factors that could increase the risk of transmission for O. stephanostomum between the two primate species. Finally, the importance of local-scale research for zoonosis risk management is important because environmental disturbance and species contact can differ, leading to different parasitological profiles between sites that are close together within the same forest patches.     

The Maturation of Ethnoprimatology: Theoretical and Methodological Pluralism

Most remaining populations of primates live in environments that have been influenced in some way by humans (e.g., protected forests bisected by major roads, forest–farm edges, and urban centers). The field of ethnoprimatology has made these environments where humans and other primates interface its primary concern, recognizing that to fully understand primate behavior, our research objectives and practice cannot be disengaged from the human dimension. During the field’s initial years, scholars drew largely from theory and technique in primate ecology and sociocultural anthropology. The contributions to this Special Issue, which include empirical research and review papers, exemplify how the ethnoprimatologist’s toolkit has since expanded to include concepts, frameworks, and methods from the natural sciences (evolutionary biology, conservation ecology, epidemiology), and the social sciences and humanities (anthropology, geography, philosophy, and science studies). Moreover, the settings in which to examine the human–primate interface have diversified to include rural, urban, mixed-landscape, and captive spaces. In this introduction, I review the emergence and scope of ethnoprimatology. I then challenge some of the critiques leveled against ethnoprimatology and highlight its broader conceptual contributions, key elements of the field’s maturation, and recent trends in theoretically and methodologically integrative scholarship in ethnoprimatology. I conclude by offering a set of postulates to guide future ethnoprimatological work that is theoretically and methodological pluralistic and positioned to advance effective primate conservation efforts and facilitate sustainable human–primate coexistence.     

Brown Bear Den Habitat and Winter Recreation in South-Central Alaska

ABSTRACT Increasing demand for backcountry recreation opportunities during winter (e.g., snowshoeing, helicopter-assisted skiing, snowmobiling) in steep, high-elevation terrain has elevated concern about disturbance to brown bears (Ursus arctos) denning on the Kenai Peninsula, Alaska, USA. To help identify areas where such conflicts might occur, we developed a spatially explicit model to predict potential den habitat. The model indicated brown bears selected locations for den sites with steep slopes, away from roads and trails. Den sites were associated with habitat high in elevation and away from potential human contact. We then compared areas with the highest probability of providing den habitat with patterns of snowmobile and nonmotorized recreation on a portion of the Kenai Peninsula. We found limited overlap between the 2 recreation activities and potential den habitat for brown bears. At the landscape scale, however, backcountry skiing overlapped more high-quality den habitat than did snowmobile riding. Our results may be used by land management agencies to identify potential conflict sites and to minimize the potential effects of recreation activities on brown bears in dens.     

Primate response to natural gas pipeline construction in the Peruvian Amazon

While natural resource exploration and extraction activity is expanding in the Neotropics, our understanding of wildlife response to such activity is almost non‐existent. Primates, which fulfill important ecological roles and face numerous anthropogenic threats, are of particular concern. We studied primate group distribution before, during, and after natural gas pipeline construction in the Peruvian Amazon to investigate whether primates spatially avoid areas of disturbance. We monitored primates on eight transects 20 times per annual sampling period in three consecutive years and analyzed changes in group observations relative to the pipeline right‐of‐way in a multi‐season occupancy modeling framework. Overall primate group encounter rates were low (<half) compared to a nearby protected area. Contrary to expectations, we did not see clear evidence of spatial avoidance of the pipeline area. Although higher overall encounter rates before construction suggested lower primate use of the area during and following construction, this pattern could not be confirmed statistically, and probability of colonization and extinction of transect sections in the occupancy analysis could not be differentiated from zero. These results are probably attributable to a combination of low numbers of primate encounters and high spatial variability in primate use of different transects. This study provides valuable preliminary data and a methodological framework for understanding the response of an ecologically important group of mammals to anthropogenic activity. We encourage other researchers to continue exploring the impacts of natural resource exploration‐ and extraction‐related activities in the tropics, as such activities are likely to have a growing effect on ecosystems.     

Spatial Ecology of Raccoons Related to Cattle and Bovine Tuberculosis in Northeastern Michigan

ABSTRACT In 1995, Mycobacterium bovis, the causative bacterium of bovine tuberculosis (bTB), was detected in 5 beef cattle operations in Alcona County, Michigan, USA. In accordance with Federal law, the operations were depopulated to prevent the spread of bTB. Subsequent wildlife surveillance programs identified high prevalence of M. bovis in mesocarnivores, including raccoons (Procyon lotor), which suggested that raccoons may be complicit in vectoring the pathogen among livestock operations. Our goal was to develop an empirical basis for generating hypotheses about the likelihood for raccoons to mediate the transmission of bTB to livestock. We found intersexual differences in scale-dependent resource selection and probability of spatial interaction that, under certain circumstances, may form the foundation for a sex-bias in disease transmission. Spatial dispersion of mixed-forest patches facilitated overlap of adjacent males, whereas female overlap zones included pastures. Within overlap zones, probabilities of interaction for male-male and male-female dyads were greater than for female-female dyads, although we documented an elevated likelihood of spatial interaction between raccoons and livestock around cattle-feeding troughs and water sources, regardless of sex. Partial regressions generated by linear models indicated that distance between nearest-neighbor mixed-forest patches explained most of this observed variation. These results supported our prediction that forest patches juxtaposed with anthropogenic features fostered social tolerance between males and, thus, facilitated spatial interaction and exploitation of anthropogenic features. In raccoons, sex and landscape composition influenced pathogen transmission potential. We suggest that livestock producers locate livestock feeding and watering features away from forest patches to mitigate future outbreaks of bTB in endemic areas.     

Measuring Microhabitat Temperature in Arboreal Primates: A Comparison of On-Animal and Stationary Approaches

Arboreal primates actively navigate a complex thermal environment that exhibits spatial, daily, and seasonal temperature changes. Thus, temperature measurements from stationary recording devices in or near a forest likely do not reflect the thermal microenvironments that primates actually experience. To better understand the thermal variation primates encounter, we attached automated temperature loggers to anklets worn by free-ranging mantled howling monkeys (Alouatta palliata) to record near-animal ambient temperatures. We compared these measures to conventional, stationary temperature measurements taken from within the forest, in nearby open fields, and at a remote weather station 38.6 km from the field site. We also measured temperatures across vertical forest heights and assessed the effects of wind speed, solar radiation, rain, and vapor pressure on primate subcutaneous temperatures (collected via implanted loggers). Ambient temperatures at measurement sites commonly used by researchers differed from those experienced by animals. Moreover, these differences changed between seasons, indicating dynamic shifts in thermal environment occur through space and time. Temperatures increased with height in the forest, with statistically significant, albeit low magnitude, differences between vertical distances of one meter. Near-animal temperatures showed that monkeys selected relatively warmer microhabitats during nighttime temperature lows and relatively cooler microhabitats during the day. Lastly, the thermal variables wind speed, solar radiation, vapor pressure, and rain were statistically associated with primate subcutaneous temperatures. Our data indicate that the temperatures arboreal primates experience are not well reflected by stationary devices. Attaching automated temperature loggers to animals provides a useful tool for more directly assessing primate microhabitat use.     

Topcats and underdogs: intraguild interactions among three apex carnivores across Asia's forestscapes

Intraguild interactions among carnivores have long held the fascination of ecologists. Ranging from competition to facilitation and coexistence, these interactions and their complex interplay influence everything from species persistence to ecosystem functioning. Yet, the patterns and pathways of such interactions are far from understood in tropical forest systems, particularly across countries in the Global South. Here, we examined the determinants and consequences of competitive interactions between dholes Cuon alpinus and the two large felids (leopards Panthera pardus and tigers Panthera tigris) with which they most commonly co-occur across Asia. Using a combination of traditional and novel data sources (N = 118), we integrate information from spatial, temporal, and dietary niche dimensions. These three species have faced catastrophic declines in their extent of co-occurrence over the past century; most of their source populations are now confined to Protected Areas. Analysis of dyadic interactions between species pairs showed a clear social hierarchy. Tigers were dominant over dholes, although pack strength in dholes helped ameliorate some of these effects; leopards were subordinate to dholes. Population-level spatio-temporal interactions assessed at 25 locations across Asia did not show a clear pattern of overlap or avoidance between species pairs. Diet-profile assessments indicated that wild ungulate biomass consumption by tigers was highest, while leopards consumed more primate and livestock prey as compared to their co-predators. In terms of prey offtake (ratio of wild prey biomass consumed to biomass available), the three species together harvested 0.4–30.2% of available prey, with the highest offtake recorded from the location where the carnivores reach very high densities. When re-examined in the context of prey availability and offtake, locations with low wild prey availability showed spatial avoidance and temporal overlap among the carnivore pairs, and locations with high wild prey availability showed spatial overlap and temporal segregation. Based on these observations, we make predictions for 40 Protected Areas in India where temporally synchronous estimates of predator and prey densities are available. We expect that low prey availability will lead to higher competition, and in extreme cases, to the complete exclusion of one or more species. In Protected Areas with high prey availability, we expect intraguild coexistence and conspecific competition among carnivores, with spill-over to forest-edge habitats and subsequent prey-switching to livestock. We stress that dhole–leopard–tiger co-occurrence across their range is facilitated through an intricate yet fragile balance between prey availability, and intraguild and conspecific competition. Data gaps and limitations notwithstanding, our study shows how insights from fundamental ecology can be of immense utility for applied aspects like large predator conservation and management of human–carnivore interactions. Our findings also highlight potential avenues for future research on tropical carnivores that can broaden current understanding of intraguild competition in forest systems of Asia and beyond.     

Rethinking Human–Nonhuman Primate Contact and Pathogenic Disease Spillover

Zoonotic transmissions are a major global health risk, and human–animal contact is frequently raised as an important driver of transmission. A literature examining zooanthroponosis largely agrees that more human–animal contact leads to more risk. Yet the basis of this proposition, the term contact, has not been rigorously analyzed. To understand how contact is used to explain cross-species spillovers, we conducted a multi-disciplinary review of studies addressing human–nonhuman primate (NHP) engagements and pathogenic transmissions and employing the term contact. We find that although contact is frequently invoked, it is employed inconsistently and imprecisely across these studies, overlooking the range of pathogens and their transmission routes and directions. We also examine a related but more expansive approach focusing on human and NHP habitats and their spatial overlap, which can potentially facilitate pathogenic transmission. Contact and spatial overlap investigations cannot, however, explain the processes that bring together people, animals and pathogens. We therefore examine another approach that enhances our understanding of zoonotic spillovers: anthropological studies identifying such historical, social, environmental processes. Comparable to a One Health approach, our ongoing research in Cameroon draws contact, spatial overlap and anthropological–historical approaches into dialog to suggest where, when and how pathogenic transmissions between people and NHPs may occur. In conclusion, we call for zoonotic disease researchers to specify more precisely the human–animal contacts they investigate and to attend to how broader ecologies, societies and histories shape pathogen–human–animal interactions.     

Predator–Primate Distribution,Activity, and Co-occurrence in Relation to Habitat and Human Activity Across Fragmented and Contiguous Forests in Northeastern Madagascar

Predator–primate interactions are understudied, yet predators have been shown to influence primate behavior, population dynamics, and spatial distribution. An understanding of these interactions is important for the successful management and conservation of these species. Novel approaches are needed to understand better the spatial relationships between predators and primates across changing landscapes. We combined photographic surveys of predators and humans with line-transect sampling of lemurs across contiguous and fragmented forests in Madagascar to 1) compare relative activity; 2) estimate probability of occupancy and detection; 3) estimate predator–primate and local people–primate co-occurrence; and 4) assess variables influencing these parameters across contiguous and fragmented forests. In fragmented (compared to contiguous) forest sites endemic predator and lemur activity were lower whereas introduced predator and local people activity were higher. Our two-species interaction occupancy models revealed a higher number of interactions among species across contiguous forest where predator and lemur occupancy were highest. Mouse lemurs show evidence of “avoidance” (SIF < 1.0) with all predator species (endemic and introduced) in contiguous forest whereas white-fronted brown lemurs show “attraction” (SIF > 1.0) with feral cats and local people in contiguous forest. Feral cats demonstrated the highest number of interactions with lemurs, despite their distribution being limited to only contiguous forest. Distance to forest edge and distance to nearby villages were important in predicting predator occupancy and detection. These results highlight the growing threat to endemic predators and lemurs as habitat loss and fragmentation increase throughout Madagascar. We demonstrate the effectiveness of a novel combination of techniques to investigate how predator species impact primate species across a gradient of forest fragmentation.     

Living in forest fragments reduces group cohesion in diademed sifakas (Propithecus diadema) in eastern Madagascar by reducing food patch size

Forest fragmentation is thought to threaten primate populations, yet the mechanisms by which this occurs remain largely unknown. However, fragmentation is known to cause dietary shifts in several primate species, and links between food resource distribution and within-group spatial dynamics are well documented. Thus, fragmentation has the potential to indirectly affect spatial dynamics, and these changes may present additional stresses to fragmented populations. I present the results from a 12-month study of Propithecus diadema at Tsinjoarivo, eastern Madagascar, including two groups in fragments and two in continuous forest. Instantaneous data on activity and spatial position were collected during all-day focal animal follows. Fragment groups had much lower cohesion, being more likely to have no neighbor within 5 and 10 m. For continuous forest groups, cohesion was highest in the rainy season (when food patches are large) and lowest in winter (when the animals rely on small-crowned mistletoes), and the chance of having no neighbor within 5 m was positively correlated with mistletoe consumption. Thus their decreased cohesion in fragment groups is inferred to result from their increased reliance on mistletoes and other small resources, which causes them to spread out among multiple patches. This scenario is consistent with the reduced body mass of subordinate individuals (males and immatures) in fragments, and suggests the occurrence of steeper within-group fitness gradients. Further research is necessary to determine whether these patterns apply to other primates; however, since fragmentation tends to cause the loss of the largest trees, many primates in fragments may lose their largest food resources and undergo similar behavioral shifts.     

Using landscape history to predict biodiversity patterns in fragmented landscapes

Landscape ecology plays a vital role in understanding the impacts of land‐use change on biodiversity, but it is not a predictive discipline, lacking theoretical models that quantitatively predict biodiversity patterns from first principles. Here, we draw heavily on ideas from phylogenetics to fill this gap, basing our approach on the insight that habitat fragments have a shared history. We develop a landscape ‘terrageny’, which represents the historical spatial separation of habitat fragments in the same way that a phylogeny represents evolutionary divergence among species. Combining a random sampling model with a terrageny generates numerical predictions about the expected proportion of species shared between any two fragments, the locations of locally endemic species, and the number of species that have been driven locally extinct. The model predicts that community similarity declines with terragenetic distance, and that local endemics are more likely to be found in terragenetically distinctive fragments than in large fragments. We derive equations to quantify the variance around predictions, and show that ignoring the spatial structure of fragmented landscapes leads to over‐estimates of local extinction rates at the landscape scale. We argue that ignoring the shared history of habitat fragments limits our ability to understand biodiversity changes in human‐modified landscapes.