Spatial Temporal Overlap Research Articles

Mesocarnivores in residential yards: influence of yard features on the occupancy, relative abundance, and overlap of coyotes, grey fox, and red fox

Context As conversion of natural areas to human development continues, there is a lack of information about how developed areas can sustainably support wildlife. While large predators are often extirpated from areas of human development, some medium-bodied mammalian predators (hereafter, mesocarnivores) have adapted to co-exist in human-dominated areas. Aims How human-dominated areas such as residential yards are used by mesocarnivores is not well understood. Our study aimed to identify yard and landscape features that influence occupancy, relative abundance and spatial-temporal overlap of three widespread mesocarnivores, namely, coyote (Canis latrans), grey fox (Urocyon cineroargenteus) and red fox (Vulpes vulpes). Methods Over the summers of 2021 and 2022, we deployed camera-traps in 46 and 96 residential yards, spanning from low-density rural areas (<1 home per km2) to more urban areas (589 homes per km2) in north-western Arkansas, USA. Key results We found that mesocarnivore occupancy was marginally influenced by yard-level features as opposed to landscape composition. Fences reduced the occupancy probability of coyotes, although they were positively associated with the total area of potential shelter sites in a yard. We found that relative abundance of grey fox was highest in yards with poultry, highlighting a likely source of conflict with homeowners. We found that all three species were primarily nocturnal and activity overlap between the species pairs was high. Conclusions Thus, these species may be using spatio-temporal partitioning to avoid antagonistic encounters and our data supported this, with few examples of species occurring in the same yards during the same 24-h period. Implications As the number of residential yards continues to grow, our results suggested that there are ways in which our yards can provide resources to mesocarnivores and that homeowners also have agency to mitigate overlap with mesocarnivores through management of their yard features.

Range-wide camera traps reveal potential prey species for Javan leopards

Prey depletion poses a threat to large carnivores worldwide. The Javan leopard (Panthera pardus melas), the last remaining apex predator on the Indonesian island of Java, is facing numerous threats from human activities including poaching, habitat loss and prey depletion. Despite the fact that the Javan leopard is an adaptable and opportunistic predator capable of surviving in various environments, our understanding of its prey and predator-prey interactions is still limited, which is crucial for their conservation. Using camera trap data collected from four national parks (i.e., Ujung Kulon, Gunung Gede Pangrango, Meru Betiri, Alas Purwo) that represent four distinct terrestrial ecoregions across the island of Java, we investigated the species richness, relative abundance, and spatial-temporal overlap in activity patterns between the Javan leopard and other animals that coexist in the same location. Our analysis of 7461 independent photos, covering 12,983 camera trap days, revealed that areas with the presence of Javan leopards exhibited higher species richness and abundance compared to those without the presence of Javan leopards. In addition, we found that the activities of banteng (Bos javanicus), barking deer (Muntiacus muntjak), Javan deer (Rusa timorensis), Javan mousedeer (Tragulus javanicus), wild boar (Sus scrofa), junglefowl (Gallus spp.), spangled ebony langur (Trachypithecus auratus), Javan rhino (Rhinoceros sondaicus), long-tailed macaque (Macaca fascicularis) and dhole (Cuon alpinus) were highly overlapping with those of Javan leopards in space and time, suggesting that these species are potential candidate prey for Javan leopards. To our knowledge, this is the first comprehensive investigation of potential prey for the Javan leopard that utilizes camera traps from all four types of terrestrial ecoregions on Java Island. The findings of this study may serve as essential information for the conservation of this critically endangered species.

Prokaryotic and eukaryotic skin microbiota modifications triggered by Leishmania infection in localized Cutaneous Leishmaniasis.

Cutaneous Leishmaniasis (CL) is a tropical disease characterized by cutaneous ulcers, sometimes with satellite lesions and nodular lymphangitis. Leishmania parasites, transmitted by sandfly vectors, cause this widespread public health challenge affecting millions worldwide. CL's complexity stems from diverse Leishmania species and intricate host interactions. Therefore, this study aims to shed light on the spatial-temporal distribution of Leishmania species and exploring the influence of skin microbiota on disease progression. We analyzed 40 samples from CL patients at three military bases across Colombia. Using Oxford Nanopore's Heat Shock Protein 70 sequencing, we identified Leishmania species and profiled microbiota in CL lesions and corresponding healthy limbs. Illumina sequencing of 16S-rRNA and 18S-rRNA genes helped analyze prokaryotic and eukaryotic communities. Our research uncovered a spatial-temporal overlap between regions of high CL incidence and our sampling locations, indicating the coexistence of various Leishmania species. L. naiffi emerged as a noteworthy discovery. In addition, our study delved into the changes in skin microbiota associated with CL lesions sampled by scraping compared with healthy skin sampled by brushing of upper and lower limbs. We observed alterations in microbial diversity, both in prokaryotic and eukaryotic communities, within the lesioned areas, signifying the potential role of microbiota in CL pathogenesis. The significant increase in specific bacterial families, such as Staphylococcaceae and Streptococcaceae, within CL lesions indicates their contribution to local inflammation. In essence, our study contributes to the ongoing research into CL, highlighting the need for a multifaceted approach to decipher the intricate interactions between Leishmaniasis and the skin microbiota.

Co-location of fisheries and offshore wind farms: Current practices and enabling conditions in the North Sea

Current expansion in offshore wind farm (OWF) development is resulting in increased spatial conflicts with other uses. In the North Sea, marine spatial planning (MSP) processes include co-existence strategies, with co-location between fisheries and offshore wind farms often discussed. However, current legal regulations and the lack of adequate scientific evidence to document economic viability of proposed passive gears, coupled with uncertainties regarding the implementation approach, continue to limit progress in developing co-location solutions. We synthesized current regulations and practices relevant to offshore wind farms and fisheries and conducted spatial-temporal overlap analysis of pot and trap fisheries targeting crustaceans in offshore wind farms to understand their potential for co-location. Our results showed the largest potential for co-location of pot and trap fisheries targeting crustaceans is located in OWFs that already exist or will be constructed until 2030. We also identified 1) gaps in fisheries and (OWF) regulations and 2) sector challenges that hindered the successful implementation of fisheries and offshore wind farm co-location. We discuss and recommend enabling conditions, including more science-based evidence on socio-economic and ecological viability of passive fisheries in offshore areas. Experiments on pot and trap gear safety and spillover evidence of artificial reef effects (AREs) are needed to inform the implementation of new safety distances and economically beneficial passive fisheries. Finally, we highlight needs for new insurance regimes and straightforward funding provision to support transitions to co-location and absorb the shocks from mobile fisheries displacement.

Combined and delayed impacts of epidemics and extreme weather on urban mobility recovery

The ever-increasing pandemic and natural disasters might spatial-temporal overlap to trigger compound disasters that disrupt urban life, including human movements. In this study, we proposed a framework for data-driven analyses on mobility resilience to uncover the compound effects of COVID-19 and extreme weather events on mobility recovery across cities with varied socioeconomic contexts. The concept of suppression risk (SR) is introduced to quantify the relative risk of mobility being reduced below the pre-pandemic baseline when certain variables deviate from their normal values. By analysing daily mobility data within and between 313 Chinese cities, we consistently observed that the highest SR under outbreaks occurred at high temperatures and abnormal precipitation levels, regardless of the type of travel, incidences, and time. Specifically, extremely high temperatures (at 35 °C) increased SR during outbreaks by 12.5%-120% but shortened the time for mobility recovery. Increased rainfall (at 20 mm/day) added SRs by 12.5%-300%, with delayed effects reflected in cross-city movements. These compound impacts, with varying lagged responses, were aggravated in cities with high population density and low GDP levels. Our findings provide quantitative evidence to inform the design of preparedness and response strategies for enhancing urban resilience in the face of future pandemics and compound disasters.

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.

Evaluating simple measures of spatial-temporal overlap as a proxy for encounter risk between a protected species and commercial fishery

Spatial and temporal assessments of overlap are becoming increasingly popular as indicators of encounter risk. The overlap in distributions between protected species and commercial fishing effort is of interest for reducing bycatch. We explored overlap between the U.S. Atlantic sea scallop fishery and loggerhead turtles (Caretta caretta) using 2 metrics, and we assessed the ability of one of those metrics to track estimated fishery interactions over time. Moderate overlap occurred between June - September; mild overlap in the spring (May) and fall (October - November); and relatively little overlap from December to April. Qualitatively, there appeared to be some correspondence between the overlap values averaged across months for each calendar year and published annual loggerhead interaction estimates with fisheries, but the predictive performance of the overlap metric was low. When data on the relative distributions of commercial fishing effort and protected species are available, simple measures of spatial and temporal overlap can provide a quick and cost-effective way to identify when and where bycatch is likely to occur. In this case study, however, overlap was limited in helping to understand the relative susceptibility of protected species to commercial fishing (i.e., magnitude of interactions). We therefore caution against using overlap as a meaningful predictor of absolute risk unless there is direct evidence to suggest a relationship.

Niche Analysis of the Main Fish in the Lhasa River Basin

The Lhasa River is one of the five tributaries of the Yarlung Zangbo River. It is the main industrial, agricultural and animal husbandry area in Tibet. It plays an important ecological security barrier role in regulating regional climate and maintaining biodiversity. In order to understand the resource utilization ability and relationship of fish in Lhasa River, and provide basic data for the protection and sustainable utilization of fish diversity in Lhasa River, the fishery resources in September 2019 (autumn), June 2020 (summer), November 2020 (winter) and March 2021 (spring) were investigated for the first time. The main fish in the catch were determined by the Index of Relative Importance (IRI). Shannon index and Pianka’s index were used to analyze the niche breadth and overlap values of the main fish caught in Lhasa River Basin from three dimensions of time, space and space–time. The results show that a total of 1399 fish of 3 orders and 4 families were collected. Among them, there is one dominant species, Schizopygopsis younghusbandi, and five common species, Schizothorax waltoni, Schizothorax oconnori, Ptychobarbus dipogon, Triplophysa stenura and Carassius auratus. The spatial–temporal niche breadth ranges from 1.395 to 3.628. They are Schizopygopsis younghusbandi, Carassius auratus, Ptychobarbus dipogon, Schizothorax oconnori, Triplophysa stenura and Schizothorax waltoni in a declining order. The temporal niche breadth is generally small, indicating that the survival activities of the main fish are greatly affected by seasonal changes. The fluctuation range of spatial–temporal overlap value is 0–0.535, and only 20% of the total logarithm is meaningful. The species pairs with temporal niche overlap values exceeding 0.300 reached 80%, while the spatial niche overlap value is generally low. The results show that the spatial and temporal distributions of the main fish in Lhasa River were quite different, and the spatial and temporal niche overlap value of the relationship between species is obviously affected by the change in spatial distribution. This demonstrates that the competition relationship and intensity of the main fish are quite different in different spatial positions.

Forward-backward electron–proton asymmetry from a two-photon crossing of diabatic states of H[formula omitted] in linearly polarized intense laser field

Controlling spatial–temporal overlap between nuclear wave packets propagating on the coupled electronic states with opposite parity by intense laser field leads to a π periodic modulation in the symmetry breaking of the coupled forward–backward electron and proton motions. The most probable directionality of electron and proton moving simultaneously in opposite directions with total electron–proton asymmetry parameter Ae−ptot=0.62 occurs at fixed carrier-envelope phases of ϑ=15° and 195°. Analysis of the time evolution of the nuclear and the electronic-nuclear wave packets on the field-dressed potentials gives rise to newly insightful images of the nonlinear nonperturbative processes for the asymmetrical localization.

Coexistence mechanisms of sympatric ungulates: Behavioral and physiological adaptations of blue sheep (Pseudois nayaur) and red deer (Cervus elaphus alxaicus) in Helan Mountains, China

Studying the coexistence mechanisms of sympatric wildlife helps to shed light on why the earth has so many different species. When ungulates share ranges, food and habitat requirements may partially or fully overlap. Therefore, the aim of this study was to determine how sympatric ungulates share limited resources. Carcasses of 27 adult blue sheep (Pseudois nayaur) and three adult red deer (Cervus elaphus alxaicus) were collected in the Helan Mountains, China. Nutritive indices of plant species foraged and morphometric measurements of the digestive system of the two sympatric ungulates were determined. In addition, 120 passive, infrared motion-triggered cameras recorded spatial overlap and temporal overlap between the two species. Camera trapping revealed relatively limited spatial overlap and significantly different activity rhythms between blue sheep and red deer. Differences were also observed in stomach weight, surface enlargement factor of the rumen, and intestine length between the two species. However, the combined relative weight of the stomach and intestine was not different between species. The low spatiotemporal overlap decreased opportunities for encounters between sympatric blue sheep and red deer, and significant differences in digestive systems allowed the two species to consume different plant species or different parts of the same species. Thus, the two sympatric ungulates coexist harmoniously in the Helan Mountains because of long-term evolutionary behavioral and physiological adaptations that eliminate negative effects on the survival of the other species.

A multi-hazard framework for spatial-temporal impact analysis

This paper aims to provide a five-step conceptual framework to analyze the impacts to the built environment from multi-hazard interactions. Our methodology includes a critical literature review and stakeholder workshops. This framework's five steps are the following: (I) identify hazards and their interactions, (II) multi-hazard modelling, (III) analysis of the hazards' spatio-temporal evolution of impacts, (IV) identification of impact interactions, (V) a multi-hazard risk or impact assessment. Our approach is based on the systematic analysis of the spatial and temporal evolution of hazards to determine potential impact interactions. In Step IV, we classify the spatial-temporal overlap of hazard impacts into four types: (i) spatial-temporal overlapping, (ii) temporal (but not spatial) overlapping, (iii) spatial overlapping (with residual and subsequent damage), (iv) independent single hazards. Building on current multi-hazard approaches and guidelines, this framework is generally applicable to a broad range of hazards, includes both hazard and impact interactions, and considers residual damage and recovery processes. The framework is applied to a real-world case study in Po Valley, Italy, of a hypothetical damage scenario from an earthquake shock that weakens the levee system, and then combined with intense rain results in a levee collapse and flood. The framework application is supported by a visualization of each step, useful to identify key elements for multi-hazard impact modelling. Practical uses of the framework include the creation of checklists for decision-making, narrowing future research needs in multi-hazard risk, and integrating multi-hazard aspects into international disaster risk management guidelines.

Interactions Between an Apex Predator and Mesopredators Across a Landscape with Human Interference

Photo 1. In the Caldén forest region of central Argentina, we installed 16 camera traps in each of 45 10 × 10-km grid cells, covering 61,611 km2, to determine interactions between carnivores and explore contributions of habitat, biotic, and anthropic factors on co-occurrence. The carnivore guild was constituted of the puma, Puma concolor (top predator; upper center of photograph), and subordinate predators (under puma, from left to right: pampas fox, Pseudalopex gymnocercus; pampas cat, Leopardus colocolo; Geoffroy's cat, Leopardus geoffroyi; and Molina's hog-nosed skunk, Conepatus chinga). Geoffroy's cats and skunks spatially avoided pumas (negative sign), but pumas did not influence pampas fox or pampas cat space use (equal sign). Photograph credits: José H. Sarasola and Juan I. Zanón Martínez. Photo 2. The study area corresponds to the Espinal phytogeographic province, mainly occupied by the Caldén forest (left), but includes interspersed sand grasslands and salt deposits (right). This forest is a xerophilic forest ecosystem dominated by Caldén trees (Prosopis caldenia), covering from 30% to 50%, and grasslands predominating over bushes. The topography is characterized by plateaus, valleys, hills, and low-altitude plains (<200 m). Photograph credit: José H. Sarasola. These photographs illustrate the article “Assessing carnivore spatial co-occurrence and temporal overlap in the face of human interference in a semiarid forest” by Juan I. Zanón Martínez, Javier Seoane, Marcella J. Kelly, José Hernán Sarasola, and Alejandro Travaini published in Ecological Applications. https://doi.org/10.1002/eap.2482.

A Hazard Identification Approach of Integrating 4D BIM and Accident Case Analysis of Spatial–Temporal Exposure

Construction sites are considered as complicated work environments. Various concurrent activities may overlap apropos to time and workspace, predisposing them to spatial–temporal exposure and repetitive accidents. Detecting the characteristics of repetitive accidents before the construction stage contributes to prevent injuries and fatalities caused by spatial—temporal conditions at construction job sites. To resolve this problem, this study proposes a novel hazard identification approach through spatial–temporal exposure analysis called HISTEA, which integrated scenario analysis of accident cases into 4D building information modeling (BIM). The proposed approach consists of three modules: (1) spatial–temporal hazard investigation (SHI) to analyze the accident cases and develop the hazard database of the spatial–temporal overlap condition of pair-wise activities; (2) spatial–temporal condition identification (SCI) to determine the conflict among different activities, considering the workspace and time overlap from the 4D BIM model; and (3) safety information integration (SII) to deliver safety knowledge to the project team through a web-based application. To illustrate and validate this approach, a HISTEA prototype for foundation work has been developed to be used at the pre-construction stage. The developed prototype is based on the analysis of 496 accident reports extracted from the integrated management information system (IMIS) of the Occupational Safety and Health Administration for the SHI module database. The proposed approach is expected to proactively aid project teams in detecting hazards that ultimately reduce repetitive accidents caused by overlapping activities.

Spatial and temporal overlaps of top predators: Dhole, tiger and leopard, and their potential preys in Huai Kha Khaeng Wildlife Sanctuary, Thailand

Abstract. Charaspet K, Sukmasuang R, Khoewsree N, Pla-Ard M, Paansri P, Keawdee B, Chanachai Y, Bhumpakphan N. 2021. Spatial and temporal overlaps of top predators: Dhole, tiger and leopard, and their potential prey in Huai Kha Khaeng Wildlife Sanctuary, Thailand. Biodiversitas 22: 580-592. The study of the spatial-temporal overlap of top predators and their prey is important to understand competition among predators and predator-prey relationships so that the viable populations of predators and other animals can be sustained. This research aimed to study the abundance of three top predators: Dhole (Cuon alpinus), tiger (Panthera tigris) and leopard (Panthera pardus), and their potential wild prey in Huai Kha Khaeng Wildlife Sanctuary, Thailand, and to investigate the spatial-temporal overlap between those three predators, and their potential wild prey. We tested two significant hypotheses: (i) tiger and leopard had the highest spatial-temporal overlap and the spatial overlap of dhole and leopard was higher in comparison to dhole and tiger due to a higher prey overlap; (ii) the three species of large carnivore avoided spatial-temporal overlap even if they were in the same area. The study was conducted using camera traps. In addition, the spatial-temporal overlap of large carnivores and their potential prey was studied to understand the important species of prey of these large carnivores. The results showed that the spatial overlap of tiger and leopard was the highest. Dhole had significant spatial overlap with leopard, which was higher in comparison to dhole and tiger. A significant temporal overlap of dhole and leopard was not found. Also, a significant temporal overlap of tiger and leopard was not found. The results were based on hypotheses that conformed to the niche overlap index of the potential prey and the temporal overlap coefficient. There were ten important species of potential prey of large carnivores: Sambar deer (Rusa unicolor), red muntjac (Muntiacus muntjak), gaur (Bos gaurus), banteng (Bos javanicus), wild boar (Sus scrofa), Malayan porcupine (Hystrix brachyura), large Indian civet (Viverra zibetha), Asiatic black bear (Ursus thibetanus), pig-tailed macaque (Macaca nemestrina) and red jungle fowl (Gallus gallus). The important recommendation is the protection of the sanctuary from wildfires which spread from the outside in, especially in dry evergreen forest. Food resources of herbivores in the area must be managed, as well as the prevention of epidemics from livestock to wild animals.

Decadal population dynamics of an intertidal bivalve (Austrovenus stutchburyi) bed: pre- and post- a mass mortality event

ABSTRACT Three independent annual surveys with some spatial–temporal overlap were amalgamated to describe the population dynamics of the New Zealand intertidal cockle (Austrovenus stutchburyi) at Lews Bay, Whangateau Harbour from 1997–2018. After more than a decade of relative stability there was a dramatic decline in the biomass (from 7.4 to 1.8 kg wet weight m−2), density (1049 to 409 individuals m−2) and mean length (22.5 to 17.7 mm) of cockles following a mass mortality event in 2009. Large (≥30 mm) cockles were more severely impacted by the die-off, suffering mortality rates of more than 80%, compared with approximately 44–55% for cockles <30 mm. Since 2009 the density of A. stutchburyi at two survey sites has steadily increased, and at one of these sites has recovered close to pre-2009 densities. However, the density of large cockles has not increased since 2009, and the mean shell length has remained stable at 17.9 mm despite protection from harvesting. This hysteresis in the recovery of population size structure suggests exceptionally slow growth rates, high mortality of young adult cockles or a change in environmental conditions that no longer supports large individuals.

Dingo Density Estimates and Movements in Equatorial Australia: Spatially Explicit Mark-Resight Models.

Simple SummaryAustralia is historically canine rabies-free but faces the threat of a rabies incursion due to the current spread of rabies through eastern Indonesia. To address this genuine concern, it is necessary to acquire further ecological knowledge on dingo populations in northern Australia to improve our predictions on the potential spread of rabies within dingoes, should an incursion occur. A one-year camera trap study was conducted in northern Australia, where the risk of the introduction of rabies is highest. Our resulting estimates of population density and home range sizes of dingoes in the study area varied according to seasons. Additionally, based on an analysis of spatial use and daily activity patterns from the camera trap pictures, a large spatial correlation and temporal overlap between dingoes and free-roaming community dogs was observed, suggesting a potential risk of disease transmission at the wild–domestic interface. This information will help improve preparedness planning for a rabies incursion in Australia.Australia is currently free of canine rabies. Spatio-ecological knowledge about dingoes in northern Australia is currently a gap that impedes the application of disease spread models and our understanding of the potential transmission of rabies, in the event of an incursion. We therefore conducted a one-year camera trap survey to monitor a dingo population in equatorial northern Australia. The population is contiguous with remote Indigenous communities containing free-roaming dogs, which potentially interact with dingoes. Based on the camera trap data, we derived dingo density and home range size estimates using maximum-likelihood, spatially explicit, mark–resight models, described dingo movements and evaluated spatial correlation and temporal overlap in activities between dingoes and community dogs. Dingo density estimates varied from 0.135 animals/km2 (95% CI = 0.127–0.144) during the dry season to 0.147 animals/km2 (95% CI = 0.135–0.159) during the wet season. The 95% bivariate Normal home range sizes were highly variable throughout the year (7.95–29.40 km2). Spatial use and daily activity patterns of dingoes and free-roaming community dogs, grouped over ~3 month periods, showed substantial temporal activity overlap and spatial correlation, highlighting the potential risk of disease transmission at the wild–domestic interface in an area of biosecurity risk in equatorial northern Australia. Our results have utility for improving preparedness against a potential rabies incursion.

Potential pesticide exposure during the post-breeding migration of the common toad (Bufo bufo) in a vineyard dominated landscape

Two important drivers of the global amphibian decline are habitat destruction due to an intensification of farming and a related increase of pesticide applications. Recent studies have shown that there might be an underestimated risk of pesticides on terrestrial amphibians. However, there are too few data on the terrestrial habitat use of amphibians in agricultural landscapes to estimate the exposure risk. To fill this knowledge gap, we used telemetry to investigate the post-breeding migration of 51 common toads (Bufo bufo) from a breeding pond in a vineyard-dominated landscape in Southern Palatinate (Germany). We expected most toads to migrate to the nearby Palatinate Forest as a terrestrial habitat. However, only four individuals reached the forest, suggesting that a part of the population is inhabiting the agricultural landscape over large parts of the year. Individuals were also found directly in the vineyards (15% of all relocations), but 23% less often than expected from a random choice and therefore tend to avoid vineyards as terrestrial habitat. To estimate a possible spatial–temporal overlap of toad migration and pesticide application, we combined telemetry data with information about pesticide applications from local wine growers. Seven individuals had a high probability (>75%) of being directly exposed to a pesticide application. Taking spray drift and the half-life values of applied pesticides into account, the number of toads potentially exposed raised to 15 individuals. We estimated that, on a single day up to 24% of the whole breeding population came in contact with pesticides, resulting in a high overall exposure risk. Pesticides can have negative effects on amphibians, and toads try to avoid vineyards as habitats. Therefore, we conclude that a heterogeneous cultural landscape, with buffer strips around ponds, uncultivated patches and migration corridors, might be the best management measure for sustaining amphibians in the agricultural landscape.

Local drivers of the structure of a tropical bird-seed dispersal network.

One of the major challenges in ecology is to understand the relative importance of neutral- and niche-based processes structuring species interactions within communities. The concept of neutral-based processes posits that network structure is a result of interactions between species based on their abundance. On the other hand, niche-based processes presume that network structure is shaped by constraints to interactions. Here, we evaluated the relative importance of neutral-based process, represented by species' abundance (A) and fruit production (F) models, and niche-based process, represented by spatial overlap (S), temporal overlap (T) and morphological barrier (M) models, in shaping the structure of a bird-seed dispersal network from the Brazilian Atlantic Forest. We evaluated the ability of each model, singly or in combination, to predict the general structure [represented by connectance, nestedness (NODF), weight nestedness (WNODF), interaction evenness and complementary specialization] and microstructure of the network (i.e., the frequency of pairwise interactions). Only nestedness (both NODF and WNODF) was predicted by at least one model. NODF and WNODF were predicted by a neutral-based process (A), by a combination of niche-based processes (ST and STM) and by both neutral- and niche-based processes (AM). NODF was also predicted by F and FM model. Regarding microstructure, temporal overlap (T) was the most parsimonious model able to predict it. Our findings reveal that a combination of neutral- and niche-based processes is a good predictor of the general structure (NODF and WNODF) of the bird-seed dispersal network and a niche-based process is the best predictor of the network's microstructure.

Periodic resource scarcity and potential for interspecific competition influences distribution of small carnivores in a seasonally dry tropical forest fragment

Small, isolated, and disturbed forest fragments potentially offer valuable habitats for small carnivore conservation. Yet the influence of resource availability—critical for survival and reproduction—on small carnivore habitat use within these modified environments is poorly understood. We conducted camera-trap surveys within a seasonally dry tropical forest fragment (148 km2) in northeastern Thailand to better understand the influence resource availability has on small carnivore habitat use within fragmented areas. Species occupancy models including both habitat and resource variables were assessed across periods of high and low resource availability (fruit abundance and rodent biomass). Species with similar resource or habitat preferences may also compete when resources are low. Therefore, we tested species with shared preferences for patterns of spatial co-occurrence and temporal overlap. Fruit availability influenced the distribution of common palm civet (Paradoxurus hermaphroditus), while rodent biomass influenced Asiatic jackal (Canis aureus), leopard cat (Prionailurus bengalensis), and small Indian civet (Viverricula indica), but only during annual periods of scarcity. In contrast, small Asian mongoose (Herpestes javanicus) was highly selective for a specific habitat (dry dipterocarp forest) regardless of seasonal fluctuations in food availability. Occupancy increased for all species during periods of resource scarcity, with leopard cat and Asiatic jackal experiencing the greatest increases (139% and 58%, respectively). Species with shared resource and habitat preferences appeared to avoid each other, either spatially or temporally. For example, leopard cat and Asiatic jackal co-occurred spatially less than would be expected, though only when rodents were scarce. Similarly, small Indian civet and small Asian mongoose, which used the same habitat and co-occurred spatially at a rate greater than expected, were active at different times. Our results indicate that seasonal resource fluctuations and interspecific interactions strongly influence the distribution of sympatric small carnivores in a fragmented forest.

Spatiotemporal patterns of Amur leopards in northeast China: Influence of tigers, prey, and humans

The Amur leopard Panthera pardus orientalis is one of the most endangered cat subspecies in the world. The rare leopard is sympatric with Amur tiger Panthera tigris altaica and their prey in human dominated landscape. To conserve the felid species, it is important to understand the activity patterns of Amur leopards, including its interactions with Amur tigers, prey, and human activities. We used a data set from 163 camera traps to quantify the spatial-temporal overlap between Amur leopards, Amur tigers, prey species, and human disturbances (e.g., humans presence on foot, vehicles, domestic dogs, and cattle grazing) from January to December 2013 in the Hunchun Nature Reserve, NE China. Our results indicated that leopards were more active in daytime and twilight; the seasonal spatial-temporal overlaps between leopards and tigers were lower than that between leopards and their prey species. Human activities and cattle grazing could influence the spatial distribution and activity patterns of the leopards, and therefore, the conservation actions should focus on reduction of human disturbances to minimize the impacts to Amur leopard activity patterns.