Birds underlie a predation-starvation risk,and foraging should show a diurnal/circadian pattern.Camera traps were used to study visitation patterns and discovery of a novel food source in woodland birds in SW Germany....Birds underlie a predation-starvation risk,and foraging should show a diurnal/circadian pattern.Camera traps were used to study visitation patterns and discovery of a novel food source in woodland birds in SW Germany.A total of 18 species occurred at feeders with nine of them being exploratory species.Great Tits(Parus major)discovered novel food sources first in most instances,and first discoveries occurred on average at 10:38,while it took 97 h for the first detection of the food source.Population size was correlated with discovery.The study supports the predation-starva-tion risk hypothesis with discovery of food sources in the morning.展开更多
The outbreak of the COVID-19 pandemic has brought massive shifts in human activities through a global blockade,directly affecting wildlife survival.However,the indirect impacts of changes in human activities are often...The outbreak of the COVID-19 pandemic has brought massive shifts in human activities through a global blockade,directly affecting wildlife survival.However,the indirect impacts of changes in human activities are often easily overlooked.We conducted surveys of Reeves's Pheasant(Syrmaticus reevesii)and its sympatric species by camera traps in forest-type nature reserves in three different scenarios:pre-lockdown,lockdown and postlockdown.An increase in livestock activities observed during the lockdown and post-lockdown period in our study area provided us an opportunity to investigate the indirect impact of the lockdown on wildlife.The prelockdown period was used as a baseline to compare any changes in trends of relative abundance index,activity patterns and temporal spacing of targeted species and livestock.During the lockdown period,the relative abundance index of livestock increased by 50%and there was an increase in daytime activity.Reeves's Pheasant showed avoidance responses to almost all sympatric species and livestock in three different periods,and the livestock avoidance level of Reeves's Pheasant during the lockdown period was significantly and positively correlated with the relative abundance index of livestock.Species-specific changes in activity patterns of study species were observed,with reduced daytime activities of Hog Badger and Raccoon Dog during and after the confinement periods.This study highlights the effect of the COVID-19 lockdown on the responses of wildlife by considering the changes in their temporal and spatial use before,during and after lockdown.The knowledge gained on wildlife during reduced human mobility because of the pandemic aids in understanding the effect of human disturbances and developing future conservation strategies in the shared space,to manage both wildlife and livestock.展开更多
As part of a larger project to examine the richness and distribution of wildlife in Kumtag Desert area, we conducted camera trapping surveys during the period 2010–2012 at seven watering sites in an arid region of th...As part of a larger project to examine the richness and distribution of wildlife in Kumtag Desert area, we conducted camera trapping surveys during the period 2010–2012 at seven watering sites in an arid region of the Altun Mountains in western China. Information on activity patterns of the wild bactrian camel (Camelus ferus), kiang (Equus kiang), goitered gazelle (Gazella subgutturosa), argali (Ovis ammon), blue sheep (Pseudois nayaur), red fox (Vulpes vulpes), and wolf (Canis lupus) was obtained. We found that the wild camel, kiang, goitered gazelle, argali, and blue sheep were predominantly diurnal at watering sites, whereas red fox and wolf were nocturnal. Five herbivores partitioned the use of watering sites in a temporal manner to minimize the risk of predation by carnivores. The wild camel was the dominant herbivorous species at the watering sites. The kiang, goitered gazelle, argali, and blue sheep displayed adaptive water use by altering spatial or temporal patterns based on the presence or absence of wild camel, to minimize the risk of interspecific strife. These results are suggestive of the differences in activity patterns that might modulate water partitioning by different species, and provide insights for the development of conservation strategies for integrated species and decisions regarding water development in the Altun Mountains.展开更多
The composition of animal species and interactions among them are widely known to shape ecological communities and fine-scale(e.g.,<1 km)monitoring of animal communities is essential for understanding the relations...The composition of animal species and interactions among them are widely known to shape ecological communities and fine-scale(e.g.,<1 km)monitoring of animal communities is essential for understanding the relationships among animals and plants.Although the co-existence of large-and medium-sized species has been studied across different scales,research on fine-scale interactions of herbivores in deciduous broadleaf forests is limited.Camera trapping of large-and medium-sized mammals was carried out over a 1 year period within a 25 ha deciduous broadleaf forest dynamics plot in the Qinling Mountains,China.Fourteen species of large-and medium-sized mammals,including six carnivores,six ungulates,one primate and one rodent species were found.Kernel density estimations were used to analyse the diel or 24 h activity patterns of all species with more than 40 independent detections and general linear models were developed to explore the spatial relationships among the species.The combination of overlapping diel activity patterns and spatial associations showed obvious niche separation among six species:giant panda(Ailuropoda melanoleuca David),takin(Budorcas taxicolor Hodgson),Reeves’s muntjac(Muntiacus reevesi Ogilby),tufted deer(Elaphodus cephalophus Milne-Edwards),Chinese serow(Capricornis milneedwardsii David)and wild boar(Sus scrofa Linnaeus).Long-term fine-scale monitoring is useful for providing information about the co-existence of species and their interactions.The results demonstrate the importance for fine-scale monitoring of animals and plants for improving understanding of species interactions and community dynamics.展开更多
Camera traps serve as an important tool for monitoring species diversity. We used data from camera traps set for capturing snow leopards(Panthera uncia) in the Yanchiwan National Nature Reserve,Gansu Province,China,...Camera traps serve as an important tool for monitoring species diversity. We used data from camera traps set for capturing snow leopards(Panthera uncia) in the Yanchiwan National Nature Reserve,Gansu Province,China,to assess species richness with respect to mammal and birds species. We also assessed survey efficiency for species detection,and conducted an initial analysis of species interactions. The survey effort of 10,171 camera workdays yielded 2,868 suitable animal image events involving 17 mammal and 20 bird species. Among these,the dhole(Cuon alpinus) is considered to be Endangered,the snow leopard and white-lipped deer(Cervus albirostris) Vulnerable,and the Pallas' s cat(Feli smanul),mountain weasel(Mustela altaica),Himalayan griffon(Gyps himalayensis) and cinereous vulture(Aegypius monachus) Near Threatened under the IUCN red list. Fourteen species were also listed as key protected wild animals according to China national standards. Both the rarefaction curves and richness estimators suggested our sampling for mammal and pheasant species is sufficient,while more survey efforts are still needed to detect other bird species. With a focus on the dominant species Eurasian lynx(Lynx lynx),occupancy models were used to estimate site use and detection probability for selected species,and to investigate predator-prey relationships between lynx on the one hand and woolly hare(Lepus oiostolus),pika(Ochotona spp.)and Tibetan partridge(Perdix hodgsoniae) on the other. We give recommendations on how to increase efficiency in camera-based species inventory and biodiversity monitoring.展开更多
Background Setting large-and medium-sized wild mammal(≥2 kg)restoration goals is important due to their role as ecosystem engineers and generalized numeric reductions.However,determining wild mammal restoration goals...Background Setting large-and medium-sized wild mammal(≥2 kg)restoration goals is important due to their role as ecosystem engineers and generalized numeric reductions.However,determining wild mammal restoration goals is very challenging due to difficulties in obtaining data on current mammal density and due to unclear information on what mammal density values should be used as a reference.Here we chose a 154 ha conservation area within one of the last remnants of the mountainous Chaco from central Argentina.We suspected that extensive and unreported defaunation had occurred due to past human pressure and the introduction of non-native mammals.To conduct the analyses,we used a simplified technique that integrates methods used in rangeland and ecological sciences.Results Eight native mammal species including only one herbivore species,and four non-native mammal species including three herbivore species were detected during 6113 camera trap days.We used known cattle densities as estimated by droppings and direct counts,together with the relative abundance indexes obtained from camera trap photos to calculate the densities of the other species,correcting for mammal size.Densities for the least and most abundant native species were 0.2 and 1.33 individuals km^(-2),respectively;and for non-native species,0.03 and 5.00 individuals km^(-2),respectively.Native and non-native species represented 0.8%and 99.2%,respectively,of the bio-mass estimates.Reference values for native herbivore biomass,as estimated from net primary productivity,were 68 times higher than values estimated for the study area(3179 vs.46.5 kg km^(-2)).Conclusions There is an urgent need to increase native mammals,with special emphasis on herbivore biomass and richness,while non-native mammal numbers must be reduced.As cattle are widespread in large portions of the globe and there is a lot of experience estimating their abundances,the ratio method we used extrapolating from cattle to other large-and medium-sized mammals could facilitate estimating mammal restoration goals in other small and defaunated areas,where traditional methods are not feasible when target mammal densities get very low.展开更多
Lowland tapir distribution is described in northwestern Bolivia and southeastern Peru within the Greater Madidi-Tambopata Landscape,a priority Tapir Conservation Unit,using 1255 distribution points derived from cam-er...Lowland tapir distribution is described in northwestern Bolivia and southeastern Peru within the Greater Madidi-Tambopata Landscape,a priority Tapir Conservation Unit,using 1255 distribution points derived from cam-era trapping efforts,field research and interviews with park guards from 5 national protected areas and hunt-ers from 19 local communities.A total of 392 independent camera trapping events from 14 camera trap surveys at 11 sites demonstrated the nocturnal and crepuscular activity patterns(86%)of the lowland tapir and provide 3 indices of relative abundance for spatial and temporal comparison.Capture rates for lowland tapirs were not significantly different between camera trapping stations placed on river beaches versus those placed in the for-est.Lowland tapir capture rates were significantly higher in the national protected areas of the region versus in-digenous territories and unprotected portions of the landscape.Capture rates through time suggested that low-land tapir populations are recovering within the Tuichi Valley,an area currently dedicated towards ecotourism activities,following the creation(1995)and subsequent implementation(1997)of the Madidi National Park in Bolivia.Based on our distributional data and published conservative estimates of population density,we calcu-lated that this transboundary landscape holds an overall lowland tapir population of between 14540 and 36351 individuals,of which at least 24.3%are under protection from national and municipal parks.As such,the Great-er Madidi-Tambopata Landscape should be considered a lowland tapir population stronghold and priority con-servation efforts are discussed in order to maintain this population.展开更多
While there are numerous wildlife ecology studies in lowland areas of Nepal,there are no in-depth studies of the hilly Churia habitat even though it comprises 7642 km2 of potential wildlife habitat across the Terai Ar...While there are numerous wildlife ecology studies in lowland areas of Nepal,there are no in-depth studies of the hilly Churia habitat even though it comprises 7642 km2 of potential wildlife habitat across the Terai Arc.We investigated tiger,leopard and prey densities across this understudied habitat.Our camera trapping survey covered 536 km2 of Churia and surrounding areas within Chitwan National Park(CNP).We used 161 trapping locations and accumulated 2097 trap-nights in a 60-day survey period during the winter season of 2010-2011.In addition,we walked 136 km over 81 different line transects using distance sampling to estimate prey density.We photographed 31 individual tigers,28 individual leopards and 25 other mammalian species.Spatial capture-recapture methods resulted in lower density estimates for tigers,ranging from 2.3 to 2.9 tigers per 100 km2,than for leopards,which ranged from 3.3 to 5.1 leopards per 100 km2.In addition,leopard densities were higher in the core of the Churia compared to surrounding areas.We estimated 62.7 prey animals per 100 km2 with forest ungulate prey(sambar,chital,barking deer and wild pig),accounting for 47%of the total.Based on prey availability,Churia habitat within CNP could potentially support 5.86 tigers per 100 km2 but our density estimates were lower,perhaps indicating that the tiger population is below carrying capacity.Our results demonstrate that Churia habitat should not be ignored in conservation initiatives,but rather management efforts should focus on reducing human disturbance to support higher predator numbers.展开更多
In order to investigate the feasibility of reintroducing the South China tiger (Panthera tigris amoyensis) in the Jiangxi Matoushan National Nature Reserve, field surveys were conducted to assess prey distribution i...In order to investigate the feasibility of reintroducing the South China tiger (Panthera tigris amoyensis) in the Jiangxi Matoushan National Nature Reserve, field surveys were conducted to assess prey distribution in the reserve. Twelve permanent transects were set in three distinct functional zones from February to April 2012 and May to July 2013. A total of 112 ungulate signs were recorded on these transects. In addition, 20 camera traps were used to survey ungulates and predators in 2012, while the following year we extended the survey site by using 30 cameras. Overall, 6641 capture events on 2930 camera days were obtained, presenting a variety of ungulate spe- cies: muntjak (Muntiacus muntjak), tufted deer (Elaphodus cephalophus), serow (Capricornis sumatraensis) and wild boar (Sus scrofa). Population structure and composition of ungulates was compared in different functional zones using a single factor of variance analysis in SPSS software. Significant differences in the distribution of un- gulates were recognized between the core zone and experimental zone, but not in other zones due to differences in habitat types and management practices of the nature reserve. Using ArcGIS analysis and Salford Predictive Modeler software, we ran several predictive models to understand which areas are most suitable for ungulates. We conclude that muntjac and wild boar are mainly distributed in the experimental zone, serow are more common in the core zone, while tufted deer are located evenly in the three functional zones. Finally, suggestions for effective and feasible management strategies and techniques for Matoushan National Nature Reserve were recom- mended based on the results and analysis in this study.展开更多
As an apex predator the Amur tiger(Panthera tigris altaica)could play a pivotal role in maintaining the integrity of forest ecosystems in Northeast Asia.Due to habitat loss and harvest over the past century,tige...As an apex predator the Amur tiger(Panthera tigris altaica)could play a pivotal role in maintaining the integrity of forest ecosystems in Northeast Asia.Due to habitat loss and harvest over the past century,tigers rapidly declined in China and are now restricted to the Russian Far East and bordering habitat in nearby China.To facilitate restoration of the tiger in its historical range,reliable estimates of population size are essential to assess effectiveness of conservation interventions.Here we used camera trap data collected in Hunchun National Nature Reserve from April to June 2013 and 2014 to estimate tiger density and abundance using both maximum likelihood and Bayesian spatially explicit capture-recapture(SECR)methods.A minimum of 8 individuals were detected in both sample periods and the documentation of marking behavior and reproduction suggests the presence of a resident population.Using Bayesian SECR modeling within the 11400 km2 state space,density estimates were 0.33 and 0.40 individuals/100 km^(2) in 2013 and 2014,respectively,corresponding to an estimated abundance of 38 and 45 animals for this transboundary Sino-Russian population.In a maximum likelihood framework,we estimated densities of 0.30 and 0.24 individuals/100 km^(2) corresponding to abundances of 34 and 27,in 2013 and 2014,respectively.These density estimates are comparable to other published estimates for resident Amur tiger populations in the Russian Far East.This study reveals promising signs of tiger recovery in Northeast China,and demonstrates the importance of connectivity between the Russian and Chinese populations for recovering tigers in Northeast China.展开更多
The coalescence time between two contacting bubbles was measured experimentally in different acoustic pressures and frequencies using an imaging system with a high-speed video camera,and taken an analysis to the influ...The coalescence time between two contacting bubbles was measured experimentally in different acoustic pressures and frequencies using an imaging system with a high-speed video camera,and taken an analysis to the influence of the secondary Bjerknes force and maximum oscillation velocity on the coalescence time of two contacting bubbles in this paper.It showed that under the action of different acoustic pressures and frequencies,the coalescence time increases with secondary force and maximum oscillation velocity.The analysis and comparison of the secondary Bjerknes force and maximum oscillation velocity for the effect of bubble coalescence time showed that the secondary Bjerknes force is the critical factor to influence the bubble coalescence.展开更多
With the extirpation of apex predators from many North American systems, coyotes Canis latrans have become the de facto top predator and are ubiquitous members of most ecosystems. Keystone predators aid in maintaining...With the extirpation of apex predators from many North American systems, coyotes Canis latrans have become the de facto top predator and are ubiquitous members of most ecosystems. Keystone predators aid in maintaining ecosystem function by regulating the mammal community through direct predation and instilling the landscape of fear, yet the value of coyotes regulating systems to this capacity is understudied and likely variable across environments. Since coyotes are common in the Midwestern United States, we utilized camera traps and occupancy analyses to as- sess their role in regulating the distribution of mammalian herbivores in a fragmented suburban ecosystem. Forest cover was a strong positive predictor of white-tailed deer Odocoileus virginianus detection, while coyote occurrence had a negative effect. Coyotes exerted a negative effect on squirrel (Sciurus spp.) and eastern cottontail rabbit Sylvilagus floridanus occurrence, while urban cover was a positive predictor for the prey species' occurrence. These results suggest all 3 species behaviorally avoid coyotes whereby deer seek denser forest cover and squirrels and cottontails mitigate risk by increasing use of urban areas. Although previous studies reveal limited influence of coyote on the rest of the carnivore guild in suburban systems, we suggest coyotes play an important role in regulating the herbivorous mammals and hence may provide similar eco- logical, benefits in urban/suburban forest fragments through trophic cascades. Furthermore, since hunting may not be allowed in urban and suburban habitats, coyotes might also serve as the pri- mary regulator of nuisance species occurring at high abundance such as white-tailed deer and squirrels.展开更多
Baird’s tapir(Tapirus bairdii)is currently endangered throughout its neotropical range with an expected popula--lished in Valle del Silencio within Parque Internacional La Amistad(PILA).Seventy-seven tapi...Baird’s tapir(Tapirus bairdii)is currently endangered throughout its neotropical range with an expected popula--lished in Valle del Silencio within Parque Internacional La Amistad(PILA).Seventy-seven tapir pictures of 15 individuals comprising 25 capture-recapture events were analyzed using mark-recapture techniques.The 100%minimum convex polygon of the sampled area was 5.7 km2 and the effective sampled area using half mean max-imum distances moved by tapirs was 7.16 km2.We estimated a tapir density of 2.93 individuals/km2 which rep-resents the highest density reported for this species.Intermountain valleys can represent unique and important habitats for large mammal species.However,the extent of isolation of this population,potentially constrained by steep slopes of the cordillera,remains unknown.Further genetic and movement studies are required to un-derstand meta-population dynamics and connectivity between lowland and highland areas for Baird’s tapir con-servation in Costa Rica.展开更多
Southeast Asia’s tropical forests suffer the highest rates of deforestation and disturbance of any on Earth,with poorly understood impacts on native fauna.Asian tapirs(Tapirus indicus)are among the least studied of t...Southeast Asia’s tropical forests suffer the highest rates of deforestation and disturbance of any on Earth,with poorly understood impacts on native fauna.Asian tapirs(Tapirus indicus)are among the least studied of the large mammals in these forests.Using records from 9 camera trap surveys in 7 of the largest(>1000 km2)pro-tected area complexes,we assessed the influence of environmental variation and human-induced disturbance on tapir occurrence.Tapirs were detected at 13%of locations sampled,significantly associated with evergreen for-est(P<0.001).A multiple logistic regression model predicted tapir presence 87%of the time.According to this model,tapir occurrence was positively influenced by annual rainfall and proximity to the forest edge.Howev-er,tapirs may not avoid edges but instead prefer wetter evergreen forest,a habitat type that tended to occur fur-ther from the forest edge at higher elevations in our particular study sites(P<0.001).By comparison,4 other wild ungulate species that share habitats with tapirs showed a range of differing responses.Tapirs are expect-ed to be less sensitive to disturbance because they are not targets for hunting and trade,and are almost entire-ly active at night,so avoid peak traffic periods in parks.Tapir populations in Thailand may be more stable than in other parts of their global range because rates of forest loss have decreased>40%over the past 20 years.We recommend surveys to fill gaps in the understanding of the status in lesser-known protected areas,research to better understand the fine-scale environmental influences on behavior and habitats of tapirs,and other forest un-gulates,and continued legal status for tapirs in the highest category of protection.展开更多
The endangered Asian tapir(Tapirus indicus)is threatened by large-scale habitat loss,forest fragmentation and increased hunting pressure.Conservation planning for this species,however,is hampered by a severe paucity o...The endangered Asian tapir(Tapirus indicus)is threatened by large-scale habitat loss,forest fragmentation and increased hunting pressure.Conservation planning for this species,however,is hampered by a severe paucity of information on its ecology and population status.We present the first Asian tapir population density estimate from a camera trapping study targeting tigers in a selectively logged forest within Peninsular Malaysia using a spatially explicit capture-recapture maximum likelihood based framework.With a trap effort of 2496 nights,17 individuals were identified corresponding to a density(standard error)estimate of 9.49(2.55)adult ta-pirs/100 km2.Although our results include several caveats,we believe that our density estimate still serves as an important baseline to facilitate the monitoring of tapir population trends in Peninsular Malaysia.Our study also highlights the potential of extracting vital ecological and population information for other cryptic individual-ly identifiable animals from tiger-centric studies,especially with the use of a spatially explicit capture-recapture maximum likelihood based framework.展开更多
Appropriate temporal and spatial scales are important prerequisites for obtaining reliable results in studies of wildlife activity patterns and interspecific interactions.The spread of camera-trap technology has incre...Appropriate temporal and spatial scales are important prerequisites for obtaining reliable results in studies of wildlife activity patterns and interspecific interactions.The spread of camera-trap technology has increased interest in and feasibility of studying the activity patterns and interspecific interactions of wildlife.However,such studies are often conducted at arbitrary spatial and temporal scales,and the methods used impose scale on the study rather than determining how activity and species interactions change with spatial scale.In this study,we used a waveletbased approach to determine the temporal and spatial scales for activity patterns and interspecific interactions on Amur leopard and their ungulate prey species that were recorded using camera traps in the main Amur leopard occurrence region in northeast China.Wavelets identified that Amur leopards were more active in spring and fall than summer,and fluctuated with periodicities of 9 and 17 days,respectively.Synchronous relationships between leopards and their prey commonly occurred in spring and fall,with a periodicity of about 20 days,indicating the appropriate seasons and temporal scales for interspecific interaction research.The influence of human activities on the activity patterns of Amur leopard or prey species often occurred over longer time periods(60–64 days).Twodimensional wavelet analyses showed that interactions between leopard and prey were more significant at spatial scales of 1 km2.Overall,our study provides a feasible approach to studying the temporal and spatial scales for wildlife activity patterns and interspecific interaction research using camera trap data.展开更多
Background:Grazing is an important management tool for maintaining healthy ecosystems and improving rangelands productivity.However,its effectiveness for this purpose is dependent on timing and frequency of grazing,as...Background:Grazing is an important management tool for maintaining healthy ecosystems and improving rangelands productivity.However,its effectiveness for this purpose is dependent on timing and frequency of grazing,as well as the type of animal.Understanding the effects of grazing management on rangeland ecosystems is critical in ensuring sustainable use of grazing resources and enhanced livestock production.This study assessed the effects of holistic grazing on animal productivity and range use pattern in Laikipia County of Kenya.Results:The results revealed that the average milk yields(106±20.1)of animals in holistic grazing areas(HGA)were significantly(p<0.05)higher than those in traditional grazing areas(TGA)(101±20.1).Weight gain of animals in HGA was significantly(0.13±0.01)higher as compared to those in TGA(0.07±0.01).The number of livestock grazing was significantly(p<0.05)higher in HGA(74±10%)than those in TGA(57±10%).In addition,the number of wildlife grazing was significantly(p<0.05)higher in HGA(74±18%)than in TGA(32±18%).Conclusions:The results indicate that holistic grazing management has the potential to improve animal performance,as well as condition of range areas as evident in the preference shown by frequent visits to HGA by both livestock and wildlife.展开更多
基金The study was partially funded by the Gips-Schüle-Stiftung,Stuttgart(Code:Stiftungsprofessur Didaktik der Biologie 27386).
文摘Birds underlie a predation-starvation risk,and foraging should show a diurnal/circadian pattern.Camera traps were used to study visitation patterns and discovery of a novel food source in woodland birds in SW Germany.A total of 18 species occurred at feeders with nine of them being exploratory species.Great Tits(Parus major)discovered novel food sources first in most instances,and first discoveries occurred on average at 10:38,while it took 97 h for the first detection of the food source.Population size was correlated with discovery.The study supports the predation-starva-tion risk hypothesis with discovery of food sources in the morning.
基金supported by the National Natural Science Foundation of China(31872240)。
文摘The outbreak of the COVID-19 pandemic has brought massive shifts in human activities through a global blockade,directly affecting wildlife survival.However,the indirect impacts of changes in human activities are often easily overlooked.We conducted surveys of Reeves's Pheasant(Syrmaticus reevesii)and its sympatric species by camera traps in forest-type nature reserves in three different scenarios:pre-lockdown,lockdown and postlockdown.An increase in livestock activities observed during the lockdown and post-lockdown period in our study area provided us an opportunity to investigate the indirect impact of the lockdown on wildlife.The prelockdown period was used as a baseline to compare any changes in trends of relative abundance index,activity patterns and temporal spacing of targeted species and livestock.During the lockdown period,the relative abundance index of livestock increased by 50%and there was an increase in daytime activity.Reeves's Pheasant showed avoidance responses to almost all sympatric species and livestock in three different periods,and the livestock avoidance level of Reeves's Pheasant during the lockdown period was significantly and positively correlated with the relative abundance index of livestock.Species-specific changes in activity patterns of study species were observed,with reduced daytime activities of Hog Badger and Raccoon Dog during and after the confinement periods.This study highlights the effect of the COVID-19 lockdown on the responses of wildlife by considering the changes in their temporal and spatial use before,during and after lockdown.The knowledge gained on wildlife during reduced human mobility because of the pandemic aids in understanding the effect of human disturbances and developing future conservation strategies in the shared space,to manage both wildlife and livestock.
基金funded by National Nonprofit Institute Research Grant of Chinese Academy of Forestry (CAFYBB2011003)the Administrative Bureau of Xinjiang Lop Nur Wild Camel National Nature Reservethe Administrative Bureau of Gansu Annanba Wild Camel National Nature Reserve for their support of this study
文摘As part of a larger project to examine the richness and distribution of wildlife in Kumtag Desert area, we conducted camera trapping surveys during the period 2010–2012 at seven watering sites in an arid region of the Altun Mountains in western China. Information on activity patterns of the wild bactrian camel (Camelus ferus), kiang (Equus kiang), goitered gazelle (Gazella subgutturosa), argali (Ovis ammon), blue sheep (Pseudois nayaur), red fox (Vulpes vulpes), and wolf (Canis lupus) was obtained. We found that the wild camel, kiang, goitered gazelle, argali, and blue sheep were predominantly diurnal at watering sites, whereas red fox and wolf were nocturnal. Five herbivores partitioned the use of watering sites in a temporal manner to minimize the risk of predation by carnivores. The wild camel was the dominant herbivorous species at the watering sites. The kiang, goitered gazelle, argali, and blue sheep displayed adaptive water use by altering spatial or temporal patterns based on the presence or absence of wild camel, to minimize the risk of interspecific strife. These results are suggestive of the differences in activity patterns that might modulate water partitioning by different species, and provide insights for the development of conservation strategies for integrated species and decisions regarding water development in the Altun Mountains.
基金This work was supported by the National Natural Science Foundation of China project(No 41671183).
文摘The composition of animal species and interactions among them are widely known to shape ecological communities and fine-scale(e.g.,<1 km)monitoring of animal communities is essential for understanding the relationships among animals and plants.Although the co-existence of large-and medium-sized species has been studied across different scales,research on fine-scale interactions of herbivores in deciduous broadleaf forests is limited.Camera trapping of large-and medium-sized mammals was carried out over a 1 year period within a 25 ha deciduous broadleaf forest dynamics plot in the Qinling Mountains,China.Fourteen species of large-and medium-sized mammals,including six carnivores,six ungulates,one primate and one rodent species were found.Kernel density estimations were used to analyse the diel or 24 h activity patterns of all species with more than 40 independent detections and general linear models were developed to explore the spatial relationships among the species.The combination of overlapping diel activity patterns and spatial associations showed obvious niche separation among six species:giant panda(Ailuropoda melanoleuca David),takin(Budorcas taxicolor Hodgson),Reeves’s muntjac(Muntiacus reevesi Ogilby),tufted deer(Elaphodus cephalophus Milne-Edwards),Chinese serow(Capricornis milneedwardsii David)and wild boar(Sus scrofa Linnaeus).Long-term fine-scale monitoring is useful for providing information about the co-existence of species and their interactions.The results demonstrate the importance for fine-scale monitoring of animals and plants for improving understanding of species interactions and community dynamics.
基金National Natural Science Foundation of China(31470567)
文摘Camera traps serve as an important tool for monitoring species diversity. We used data from camera traps set for capturing snow leopards(Panthera uncia) in the Yanchiwan National Nature Reserve,Gansu Province,China,to assess species richness with respect to mammal and birds species. We also assessed survey efficiency for species detection,and conducted an initial analysis of species interactions. The survey effort of 10,171 camera workdays yielded 2,868 suitable animal image events involving 17 mammal and 20 bird species. Among these,the dhole(Cuon alpinus) is considered to be Endangered,the snow leopard and white-lipped deer(Cervus albirostris) Vulnerable,and the Pallas' s cat(Feli smanul),mountain weasel(Mustela altaica),Himalayan griffon(Gyps himalayensis) and cinereous vulture(Aegypius monachus) Near Threatened under the IUCN red list. Fourteen species were also listed as key protected wild animals according to China national standards. Both the rarefaction curves and richness estimators suggested our sampling for mammal and pheasant species is sufficient,while more survey efforts are still needed to detect other bird species. With a focus on the dominant species Eurasian lynx(Lynx lynx),occupancy models were used to estimate site use and detection probability for selected species,and to investigate predator-prey relationships between lynx on the one hand and woolly hare(Lepus oiostolus),pika(Ochotona spp.)and Tibetan partridge(Perdix hodgsoniae) on the other. We give recommendations on how to increase efficiency in camera-based species inventory and biodiversity monitoring.
基金CONICET-Argentina under Grant PIP#11220170100143C which funded 4 of the camera trapsCONCYTEC-Peru under grant contract No.187-2019-FONDECYT which funded the stay of HRQM in Córdoba,Argentina.
文摘Background Setting large-and medium-sized wild mammal(≥2 kg)restoration goals is important due to their role as ecosystem engineers and generalized numeric reductions.However,determining wild mammal restoration goals is very challenging due to difficulties in obtaining data on current mammal density and due to unclear information on what mammal density values should be used as a reference.Here we chose a 154 ha conservation area within one of the last remnants of the mountainous Chaco from central Argentina.We suspected that extensive and unreported defaunation had occurred due to past human pressure and the introduction of non-native mammals.To conduct the analyses,we used a simplified technique that integrates methods used in rangeland and ecological sciences.Results Eight native mammal species including only one herbivore species,and four non-native mammal species including three herbivore species were detected during 6113 camera trap days.We used known cattle densities as estimated by droppings and direct counts,together with the relative abundance indexes obtained from camera trap photos to calculate the densities of the other species,correcting for mammal size.Densities for the least and most abundant native species were 0.2 and 1.33 individuals km^(-2),respectively;and for non-native species,0.03 and 5.00 individuals km^(-2),respectively.Native and non-native species represented 0.8%and 99.2%,respectively,of the bio-mass estimates.Reference values for native herbivore biomass,as estimated from net primary productivity,were 68 times higher than values estimated for the study area(3179 vs.46.5 kg km^(-2)).Conclusions There is an urgent need to increase native mammals,with special emphasis on herbivore biomass and richness,while non-native mammal numbers must be reduced.As cattle are widespread in large portions of the globe and there is a lot of experience estimating their abundances,the ratio method we used extrapolating from cattle to other large-and medium-sized mammals could facilitate estimating mammal restoration goals in other small and defaunated areas,where traditional methods are not feasible when target mammal densities get very low.
文摘Lowland tapir distribution is described in northwestern Bolivia and southeastern Peru within the Greater Madidi-Tambopata Landscape,a priority Tapir Conservation Unit,using 1255 distribution points derived from cam-era trapping efforts,field research and interviews with park guards from 5 national protected areas and hunt-ers from 19 local communities.A total of 392 independent camera trapping events from 14 camera trap surveys at 11 sites demonstrated the nocturnal and crepuscular activity patterns(86%)of the lowland tapir and provide 3 indices of relative abundance for spatial and temporal comparison.Capture rates for lowland tapirs were not significantly different between camera trapping stations placed on river beaches versus those placed in the for-est.Lowland tapir capture rates were significantly higher in the national protected areas of the region versus in-digenous territories and unprotected portions of the landscape.Capture rates through time suggested that low-land tapir populations are recovering within the Tuichi Valley,an area currently dedicated towards ecotourism activities,following the creation(1995)and subsequent implementation(1997)of the Madidi National Park in Bolivia.Based on our distributional data and published conservative estimates of population density,we calcu-lated that this transboundary landscape holds an overall lowland tapir population of between 14540 and 36351 individuals,of which at least 24.3%are under protection from national and municipal parks.As such,the Great-er Madidi-Tambopata Landscape should be considered a lowland tapir population stronghold and priority con-servation efforts are discussed in order to maintain this population.
文摘While there are numerous wildlife ecology studies in lowland areas of Nepal,there are no in-depth studies of the hilly Churia habitat even though it comprises 7642 km2 of potential wildlife habitat across the Terai Arc.We investigated tiger,leopard and prey densities across this understudied habitat.Our camera trapping survey covered 536 km2 of Churia and surrounding areas within Chitwan National Park(CNP).We used 161 trapping locations and accumulated 2097 trap-nights in a 60-day survey period during the winter season of 2010-2011.In addition,we walked 136 km over 81 different line transects using distance sampling to estimate prey density.We photographed 31 individual tigers,28 individual leopards and 25 other mammalian species.Spatial capture-recapture methods resulted in lower density estimates for tigers,ranging from 2.3 to 2.9 tigers per 100 km2,than for leopards,which ranged from 3.3 to 5.1 leopards per 100 km2.In addition,leopard densities were higher in the core of the Churia compared to surrounding areas.We estimated 62.7 prey animals per 100 km2 with forest ungulate prey(sambar,chital,barking deer and wild pig),accounting for 47%of the total.Based on prey availability,Churia habitat within CNP could potentially support 5.86 tigers per 100 km2 but our density estimates were lower,perhaps indicating that the tiger population is below carrying capacity.Our results demonstrate that Churia habitat should not be ignored in conservation initiatives,but rather management efforts should focus on reducing human disturbance to support higher predator numbers.
基金Conservation and monitoring technology research on wild tigers in China(2011-LYSJWT-08)
文摘In order to investigate the feasibility of reintroducing the South China tiger (Panthera tigris amoyensis) in the Jiangxi Matoushan National Nature Reserve, field surveys were conducted to assess prey distribution in the reserve. Twelve permanent transects were set in three distinct functional zones from February to April 2012 and May to July 2013. A total of 112 ungulate signs were recorded on these transects. In addition, 20 camera traps were used to survey ungulates and predators in 2012, while the following year we extended the survey site by using 30 cameras. Overall, 6641 capture events on 2930 camera days were obtained, presenting a variety of ungulate spe- cies: muntjak (Muntiacus muntjak), tufted deer (Elaphodus cephalophus), serow (Capricornis sumatraensis) and wild boar (Sus scrofa). Population structure and composition of ungulates was compared in different functional zones using a single factor of variance analysis in SPSS software. Significant differences in the distribution of un- gulates were recognized between the core zone and experimental zone, but not in other zones due to differences in habitat types and management practices of the nature reserve. Using ArcGIS analysis and Salford Predictive Modeler software, we ran several predictive models to understand which areas are most suitable for ungulates. We conclude that muntjac and wild boar are mainly distributed in the experimental zone, serow are more common in the core zone, while tufted deer are located evenly in the three functional zones. Finally, suggestions for effective and feasible management strategies and techniques for Matoushan National Nature Reserve were recom- mended based on the results and analysis in this study.
基金supported by grants from the Natural Science Foundation of China(31270567,31210103911,31421063,31200410 and 31470566)the National Scientific and Technical Foundation Project of China(2012FY112000).
文摘As an apex predator the Amur tiger(Panthera tigris altaica)could play a pivotal role in maintaining the integrity of forest ecosystems in Northeast Asia.Due to habitat loss and harvest over the past century,tigers rapidly declined in China and are now restricted to the Russian Far East and bordering habitat in nearby China.To facilitate restoration of the tiger in its historical range,reliable estimates of population size are essential to assess effectiveness of conservation interventions.Here we used camera trap data collected in Hunchun National Nature Reserve from April to June 2013 and 2014 to estimate tiger density and abundance using both maximum likelihood and Bayesian spatially explicit capture-recapture(SECR)methods.A minimum of 8 individuals were detected in both sample periods and the documentation of marking behavior and reproduction suggests the presence of a resident population.Using Bayesian SECR modeling within the 11400 km2 state space,density estimates were 0.33 and 0.40 individuals/100 km^(2) in 2013 and 2014,respectively,corresponding to an estimated abundance of 38 and 45 animals for this transboundary Sino-Russian population.In a maximum likelihood framework,we estimated densities of 0.30 and 0.24 individuals/100 km^(2) corresponding to abundances of 34 and 27,in 2013 and 2014,respectively.These density estimates are comparable to other published estimates for resident Amur tiger populations in the Russian Far East.This study reveals promising signs of tiger recovery in Northeast China,and demonstrates the importance of connectivity between the Russian and Chinese populations for recovering tigers in Northeast China.
基金supported by the National Natural Science Foundation for Young Scholars of China(11504173)by the Self-determined Research Program of Nanjing University of Science&Technology(No.30915118806)
文摘The coalescence time between two contacting bubbles was measured experimentally in different acoustic pressures and frequencies using an imaging system with a high-speed video camera,and taken an analysis to the influence of the secondary Bjerknes force and maximum oscillation velocity on the coalescence time of two contacting bubbles in this paper.It showed that under the action of different acoustic pressures and frequencies,the coalescence time increases with secondary force and maximum oscillation velocity.The analysis and comparison of the secondary Bjerknes force and maximum oscillation velocity for the effect of bubble coalescence time showed that the secondary Bjerknes force is the critical factor to influence the bubble coalescence.
文摘With the extirpation of apex predators from many North American systems, coyotes Canis latrans have become the de facto top predator and are ubiquitous members of most ecosystems. Keystone predators aid in maintaining ecosystem function by regulating the mammal community through direct predation and instilling the landscape of fear, yet the value of coyotes regulating systems to this capacity is understudied and likely variable across environments. Since coyotes are common in the Midwestern United States, we utilized camera traps and occupancy analyses to as- sess their role in regulating the distribution of mammalian herbivores in a fragmented suburban ecosystem. Forest cover was a strong positive predictor of white-tailed deer Odocoileus virginianus detection, while coyote occurrence had a negative effect. Coyotes exerted a negative effect on squirrel (Sciurus spp.) and eastern cottontail rabbit Sylvilagus floridanus occurrence, while urban cover was a positive predictor for the prey species' occurrence. These results suggest all 3 species behaviorally avoid coyotes whereby deer seek denser forest cover and squirrels and cottontails mitigate risk by increasing use of urban areas. Although previous studies reveal limited influence of coyote on the rest of the carnivore guild in suburban systems, we suggest coyotes play an important role in regulating the herbivorous mammals and hence may provide similar eco- logical, benefits in urban/suburban forest fragments through trophic cascades. Furthermore, since hunting may not be allowed in urban and suburban habitats, coyotes might also serve as the pri- mary regulator of nuisance species occurring at high abundance such as white-tailed deer and squirrels.
文摘Baird’s tapir(Tapirus bairdii)is currently endangered throughout its neotropical range with an expected popula--lished in Valle del Silencio within Parque Internacional La Amistad(PILA).Seventy-seven tapir pictures of 15 individuals comprising 25 capture-recapture events were analyzed using mark-recapture techniques.The 100%minimum convex polygon of the sampled area was 5.7 km2 and the effective sampled area using half mean max-imum distances moved by tapirs was 7.16 km2.We estimated a tapir density of 2.93 individuals/km2 which rep-resents the highest density reported for this species.Intermountain valleys can represent unique and important habitats for large mammal species.However,the extent of isolation of this population,potentially constrained by steep slopes of the cordillera,remains unknown.Further genetic and movement studies are required to un-derstand meta-population dynamics and connectivity between lowland and highland areas for Baird’s tapir con-servation in Costa Rica.
基金funded by the TRF/BIOTEC Special Program for Biodiversity Research and Training grant BRT-R353008 and BRT-R346001.
文摘Southeast Asia’s tropical forests suffer the highest rates of deforestation and disturbance of any on Earth,with poorly understood impacts on native fauna.Asian tapirs(Tapirus indicus)are among the least studied of the large mammals in these forests.Using records from 9 camera trap surveys in 7 of the largest(>1000 km2)pro-tected area complexes,we assessed the influence of environmental variation and human-induced disturbance on tapir occurrence.Tapirs were detected at 13%of locations sampled,significantly associated with evergreen for-est(P<0.001).A multiple logistic regression model predicted tapir presence 87%of the time.According to this model,tapir occurrence was positively influenced by annual rainfall and proximity to the forest edge.Howev-er,tapirs may not avoid edges but instead prefer wetter evergreen forest,a habitat type that tended to occur fur-ther from the forest edge at higher elevations in our particular study sites(P<0.001).By comparison,4 other wild ungulate species that share habitats with tapirs showed a range of differing responses.Tapirs are expect-ed to be less sensitive to disturbance because they are not targets for hunting and trade,and are almost entire-ly active at night,so avoid peak traffic periods in parks.Tapir populations in Thailand may be more stable than in other parts of their global range because rates of forest loss have decreased>40%over the past 20 years.We recommend surveys to fill gaps in the understanding of the status in lesser-known protected areas,research to better understand the fine-scale environmental influences on behavior and habitats of tapirs,and other forest un-gulates,and continued legal status for tapirs in the highest category of protection.
文摘The endangered Asian tapir(Tapirus indicus)is threatened by large-scale habitat loss,forest fragmentation and increased hunting pressure.Conservation planning for this species,however,is hampered by a severe paucity of information on its ecology and population status.We present the first Asian tapir population density estimate from a camera trapping study targeting tigers in a selectively logged forest within Peninsular Malaysia using a spatially explicit capture-recapture maximum likelihood based framework.With a trap effort of 2496 nights,17 individuals were identified corresponding to a density(standard error)estimate of 9.49(2.55)adult ta-pirs/100 km2.Although our results include several caveats,we believe that our density estimate still serves as an important baseline to facilitate the monitoring of tapir population trends in Peninsular Malaysia.Our study also highlights the potential of extracting vital ecological and population information for other cryptic individual-ly identifiable animals from tiger-centric studies,especially with the use of a spatially explicit capture-recapture maximum likelihood based framework.
基金This study was funded by the Fundamental Research Funds for the Central Universities(2572017PZ14)the National Key Programme of Research and Development,Ministry of Science and Technology(2016YFC0503200)+1 种基金NSFC(31872241,31572285)to G.J.full-time postdoctoral support program of Northeast Forestry University(60201103)to J.Q.
文摘Appropriate temporal and spatial scales are important prerequisites for obtaining reliable results in studies of wildlife activity patterns and interspecific interactions.The spread of camera-trap technology has increased interest in and feasibility of studying the activity patterns and interspecific interactions of wildlife.However,such studies are often conducted at arbitrary spatial and temporal scales,and the methods used impose scale on the study rather than determining how activity and species interactions change with spatial scale.In this study,we used a waveletbased approach to determine the temporal and spatial scales for activity patterns and interspecific interactions on Amur leopard and their ungulate prey species that were recorded using camera traps in the main Amur leopard occurrence region in northeast China.Wavelets identified that Amur leopards were more active in spring and fall than summer,and fluctuated with periodicities of 9 and 17 days,respectively.Synchronous relationships between leopards and their prey commonly occurred in spring and fall,with a periodicity of about 20 days,indicating the appropriate seasons and temporal scales for interspecific interaction research.The influence of human activities on the activity patterns of Amur leopard or prey species often occurred over longer time periods(60–64 days).Twodimensional wavelet analyses showed that interactions between leopard and prey were more significant at spatial scales of 1 km2.Overall,our study provides a feasible approach to studying the temporal and spatial scales for wildlife activity patterns and interspecific interaction research using camera trap data.
基金funded by Princeton University and Mpala Research Center.
文摘Background:Grazing is an important management tool for maintaining healthy ecosystems and improving rangelands productivity.However,its effectiveness for this purpose is dependent on timing and frequency of grazing,as well as the type of animal.Understanding the effects of grazing management on rangeland ecosystems is critical in ensuring sustainable use of grazing resources and enhanced livestock production.This study assessed the effects of holistic grazing on animal productivity and range use pattern in Laikipia County of Kenya.Results:The results revealed that the average milk yields(106±20.1)of animals in holistic grazing areas(HGA)were significantly(p<0.05)higher than those in traditional grazing areas(TGA)(101±20.1).Weight gain of animals in HGA was significantly(0.13±0.01)higher as compared to those in TGA(0.07±0.01).The number of livestock grazing was significantly(p<0.05)higher in HGA(74±10%)than those in TGA(57±10%).In addition,the number of wildlife grazing was significantly(p<0.05)higher in HGA(74±18%)than in TGA(32±18%).Conclusions:The results indicate that holistic grazing management has the potential to improve animal performance,as well as condition of range areas as evident in the preference shown by frequent visits to HGA by both livestock and wildlife.