Identifying home ranges—those areas traversed by individuals in their normal foraging,mating,and parenting activities—is an important aspect of cetacean study.Understanding these ranges facilitates identification of...Identifying home ranges—those areas traversed by individuals in their normal foraging,mating,and parenting activities—is an important aspect of cetacean study.Understanding these ranges facilitates identification of resource use and conservation.Fin and humpback whales occur in Antarctica during the austral summer,but information regarding their home ranges is limited.Using opportunistically collected whale sighting data from eight consecutive summer seasons spanning 2010–2017,we approximate the home ranges of humpback and fin whales around Drake Passage(DRA),West of Antarctic Peninsula(WAP),South Shetland Islands(SSI),an area northwest of the Weddell Sea(WED),and around the South Orkney Islands(SOI).Approximate home ranges are identified using Kernel Density Estimation(KDE).Most fin whales occurred north and northwest of the SOI,which suggests that waters near these islands support concentrations of this species.Most humpback whales were observed around the SSI,but unlike fin whales,their distributions were highly variable in other areas.KDE suggests spatial segregation in areas where both species exist such as SOI,SSI,and WPA.Partial redundancy analysis(pRDA)suggests that the distributions of these species are more affected by spatial variables(latitude,longitude)than by local scale variables such as sea surface temperature and depth.This study presents a visual approximation of the home ranges of fin and humpback whales,and identifies variation in the effects of space and environmental variables on the distributions of these whales at different spatial scales.展开更多
Home range is an important ecological parameter reflecting the suita bility of animal habitats.To study the size and factors influencing the home ranges of the Qinghai toad-headed lizard(Phr ynocephalus vlangalii)in d...Home range is an important ecological parameter reflecting the suita bility of animal habitats.To study the size and factors influencing the home ranges of the Qinghai toad-headed lizard(Phr ynocephalus vlangalii)in different habitats,from July to September 2020,we radio-tagged and tracked 15 individuals in each of sites distributed at high(3600 m)and low(2600 m)altitudes on the Dangjin Mountain,Gansu Province,northwest China.We calculated home range size using the 100%minimum convex polygon method,and analyzed the influence of inherent lizard characteristics and external environmental factors.Our results revealed that for both high-and lowaltitude lizard populations,the sizes of home ranges were positively correlated with lizard body mass.Moreover,after eliminating the effect of body mass as a covariable,we established that the home ranges of high-altitude lizards(5255.1±1103.8 m^(2))were larger than those of the low-altitude lizards(2208.1±348.7 m^(2)).Lizards in the high-altitude population were also characterized by longer daily suitable activity times and spent significantly more time in full sunlight than those in the low-altitude population.Furthermore,the food resources for lizards in low-altitude habitats were more abundant than those in high-altitude habitats In conclusion,we established that P.vlangalii lizards inhabiting high-altitude sites had larger home ranges than conspecific lizards distributed at a lower altitude,which was associated not only with endogenous factors,such as body mass,but also with habitat-related environmental factors,such as the quality of thermal resources and availability of food.展开更多
The home ranges of the Narcissus Flycatcher(Ficedula narcissina elisae)and the Yellow-rumped Fly-catcher(F.zanthopygia)are measured by radio telemetry in a subalpine forest near Beijing,China.The home range is calcula...The home ranges of the Narcissus Flycatcher(Ficedula narcissina elisae)and the Yellow-rumped Fly-catcher(F.zanthopygia)are measured by radio telemetry in a subalpine forest near Beijing,China.The home range is calculated by 100%Minimum Convex Polygon(MCP),and the area varies from 2,000 to 5,000 m2.The majority of fly-catchers can be found in the bottom of valleys and the under-side of mountains.It is fairly rare for both Flycatcher species to leave their nests more than 70 m.Individuals of the species in pair-banding and nest-detecting periods have larger home ranges than those in incubation and rearing periods.The levels of canopy coverage in the home ranges of Narcissus Flycatchers are significantly higher than that of Yellow-rumped Flycatchers.There are also more tall trees and stumps in the home ranges of Narcissus Flycatchers than in that of Yellow-rumped Flycatchers.The dominant tree species in the home ranges of Narcissus Flycatchers is Dahurian Birch(Betula dahurica),whereas Manchurian Walnut(Juglans mandshurica)is the dominant tree species in the home ranges of Yellow-rumped Flycatchers.展开更多
With the loss of substantial natural wetlands in coastal zones,artificial wetlands provide alternative habitats for many shorebirds.Scientific management of artificial wetlands used by shorebirds plays an important ro...With the loss of substantial natural wetlands in coastal zones,artificial wetlands provide alternative habitats for many shorebirds.Scientific management of artificial wetlands used by shorebirds plays an important role in maintaining the stability of shorebird population.Satellite tracking technique can obtain high-precision location information of individuals day and night,providing a good technical support for the study of quantitative relationship between waterfowls and their habitats.In this study,satellite tracking method,Remote Sensing(RS)and Geographic Information System(GIS)technology were used to analyze the activity pattern and habitat utilization characteristics of Pied Avocet during breeding period in an artificial wetland complex in the Yellow River Delta(YRD),China.The results showed that the breeding Pied Avocets had a small range of activity,with a total core and main home range of 33.10 km^(2) and 216.30 km^(2),respectively.This species tended to forage in the pond and salt pan during the day and night,respectively,with an unfixed staying time in the breeding ground.The distance between breeding ground and feeding ground was less than 6 km.It is emphasized that in addition to improving the conditions of the remaining natural habitats,effective managing artificial habitats is a priority for shorebird conservation.This research could provide reference for the management of artificial wetlands in coastal zones and supply technique support for the protection of shorebirds and their habitats,and alleviate human-bird conflicts and sustainable development of coastal zones.展开更多
Background:There is increasing interest in evaluating home-range overlap(or,otherwise,segregation)between bird species,and between or within bird populations,to inform spatial planning.So far,studies of home-range ove...Background:There is increasing interest in evaluating home-range overlap(or,otherwise,segregation)between bird species,and between or within bird populations,to inform spatial planning.So far,studies of home-range overlap typically make use of comparisons between pairs of individuals,populations or species,and return a matrix of pairwise overlaps(e.g.,percent overlaps).However,when the number of individuals,populations or species to be compared is elevated,an overlarge overlap matrix is difficult to interpret from an ecological viewpoint.Methods:We propose here a new,conceptually simple and computationally efficient index(general overlap index;GOI)for the ready computation within GIS of home range overlap of an arbitrarily large number(i.e.,n≥2)of individuals,populations or species.Whatever the number of home ranges to be compared,GOI always returns a single score between 0 and 100.As a case study,we applied our index to 24,074 GPS points of 10 Lesser Kestrels(Falco naumanni)in order to estimate within-colony and between-colony overlaps in two neighboring colonies in Southern Italy.Results:Within-colony overlap was elevated for both colonies(96.41%at Cassano delle Murge,n=5 individuals;81.38%at Santeramo in Colle,n=5 individuals),while between-colony overlap was low(19.12%;n=2 colonies)and,after a randomization procedure,more spatially-segregated than expected by chance.Conclusions:Modern biotelemetry offers huge amounts of data describing the space use of animal species.The use of intuitive and straightforward indices,like GOI,can be useful to promptly extract ecological information from such an amount of data(e.g.detecting change in space use over successive years,evaluating the reliability of various home-range estimators).展开更多
A critical function of animal movement is to maximize access to essential resources in temporally fluctuating and spatially heterogeneous environments.Seasonally mediated resource fluctuations may influence animal mov...A critical function of animal movement is to maximize access to essential resources in temporally fluctuating and spatially heterogeneous environments.Seasonally mediated resource fluctuations may influence animal movements,enabling them to track changing resource distributions,resulting in annual migration patterns.The conservation-dependent giant panda(Ailuropoda melanoleuca) displays seasonal movement patterns;however,the key factor driving these seasonal migration patterns remains poorly understood.Here,we used GPS tracking collars to monitor the movements of six giant pandas over a 12-year period across different elevations,and performed statistical analysis of seasonal migration directions,routes,habitat revisitation,home range overlap,first arrival events,and stability.Our results revealed a compelling pattern of seasonal migrations that facilitated the ability of the pandas to forage at the appropriate time and place to maximize nutritional intake.Our results indicated that pandas utilize spatial memory to locate reliable food resources,as evidenced by their annual return to the same or similar winter and summer home ranges and the consistently maintained percentage of home range overlap.These novel insights into giant panda foraging and movement ecology not only enhance our understanding of its ability to adapt to nutritionally poor dietary resources but also provide important information for the development of resource utilization-based protection and management strategies.展开更多
Home range studies are essential for understanding an animal’s behavioral ecology and for making wildlife conservation efficient.The home range of a group of Yunnan snub-nosed monkeys(Rhinopithecus bieti Milne-Edward...Home range studies are essential for understanding an animal’s behavioral ecology and for making wildlife conservation efficient.The home range of a group of Yunnan snub-nosed monkeys(Rhinopithecus bieti Milne-Edwards,1897)was estimated using a global positioning system collar from December 2003 to October 2004 in northern Yunnan Province,China.To measure the ranging area of the study group 1291 animal locations were fixed.Based on the 100%minimum convex polygon method,the home range size was approximately 32.8 km2;based on the grid-cell method it was approximately 17.8 km2 using a 250-m grid and 23.3 km2 using a 500-m grid.We assessed seasonal changes in the home range of this monkey population and found a different ranging pattern of from earlier studies.Daily range size was calculated as 4.80±5.81 ha(mean±standard deviation),with a range of 45.66 ha(0.01–45.67 ha).展开更多
Rodents are reservoirs of various types of hantavirus,some of which are agents of hantavirus pulmonary syndrome in humans.Each hantavirus is associated with a single rodent host species but successive spill-over event...Rodents are reservoirs of various types of hantavirus,some of which are agents of hantavirus pulmonary syndrome in humans.Each hantavirus is associated with a single rodent host species but successive spill-over events may eventually lead to host-switching and new species’becoming host of a given pathogen.This study aims to gain an understanding of the spatial ecology of two hantavirus-host species,Akodon azarae,and Oligoryzomys flavescens,by identifying factors modulating their home range sizes and stability,and by evaluating intra-and interspecific spatial aggregation for these species and a third one—Oxymycterus rufus—living in sympatry.For this,eleven capture-mark-recapture surveys were carried out,spanning 22 months.We found that A.azarae males have larger and more mobile home ranges than females,independently of the season.Consequently,males could likely have a more relevant role in the transmission of hantavirus because of their greater exposure both to a higher number of contacts between individuals and viral contamination of the environment.Contrasting,O.flavescens individuals showed negligible displacements of their home range through time,which could limit the range of hantavirus spread in host populations.Since O.flavescens is host to Lechiguanas hantavirus(pathogenic to humans)this result encompasses epidemiological relevance,for it may imply the existence of local foci of infection.Additionally,individuals of both species performed excursions outside their home ranges.These events could enable hantavirus spread over distances beyond the normal range of movements and lead to new hantavirus outbreaks in formerly non-infected rodent populations,favoring the persistence of the virus in nature.展开更多
Home range and habitat use of male Reeves’s pheasant(Syrmaticus reevesii)were studied during winter of 2001~2002 and 2002~2003 in the Dongzhai National Nature Reserve,Henan Province.Results from five individuals of R...Home range and habitat use of male Reeves’s pheasant(Syrmaticus reevesii)were studied during winter of 2001~2002 and 2002~2003 in the Dongzhai National Nature Reserve,Henan Province.Results from five individuals of Reeves’s pheasant with over 30 relocations,indicated that the average size of home range was 10.03±1.17 hm^(2) by Minimum Convex Polygon method,8.60±0.35 hm^(2) by 90%Harmonic Mean Transformation method,and 9.50±1.90 hm^(2) by 95%Fixed Kernel method.It was observed that the winter range is smaller than that in the breeding season.The mean core area of the home range was found to be 1.88±0.37 hm^(2).Although the habitat composition of the core area varied greatly for individuals,a large part of the habitats used were composed of conifer and broadleaf mixed forests,masson pine forests,fir forests,and shrubs.Habitat use within the study area was non-random,while habitats within home ranges were randomly used.Habitat use was dictated by tree diameter at breast height,shrub height and coverage at 2.0 m.The proximity between forests and shrubs were also found to be important in providing refuge for the birds during winter.Recommendations for conservation management include protecting the existing habitats in Dongzhai National Nature Reserve,increasing suitable habitat for Reeves’s Pheasant through artificial plantations(e.g.firs),and restoring some parts of the large shrub area into forests.展开更多
Hainan gibbons are among the world’s most critically endangered primates,with a remaining population of only 35 individuals distributed across 5 social groups in the Bawangling Branch of the Hainan Tropical Rainfores...Hainan gibbons are among the world’s most critically endangered primates,with a remaining population of only 35 individuals distributed across 5 social groups in the Bawangling Branch of the Hainan Tropical Rainforest National Park,China.Habitat conversion and forest fragmentation over the past 40 years have reduced their geographical distribution by 95%.In the absence of a quantitative assessment of the availability of remaining suitable habitat,it is unclear whether this species can survive to the end of this century.We used behavioral observations,ArcGIS,remote sensing,stereo optical imagery,and MaxEnt modeling to identify patterns of Hainan gibbon range use and compare changes in the distribution of suitable forest types and areas of forest fragmentation over the past 20 years(2000–2020).The results indicate that the combined range of the 5 extant Hainan gibbon groups totaled 14.89 km2.The home range of the smallest group(Group E,3 individuals)was 1.51 km2,which likely represents the minimum home range size for this species.The remaining area of highly suitable and moderately suitable habitat totals 26.9 km2.However,habitat connectivity across the gibbon range is very low(less than 0.5),limiting the ability of Hainan gibbons to move between forest patches.The results of this study indicate that the availability of suitable habitat in Bawangling is insufficient to allow for future Hainan gibbon population growth.Therefore,immediate action must be taken to restore,reforest,and establish ecological corridors to reconnect areas of suitable habitat for these critically endangered gibbons.展开更多
To better understand the spatial structure of Amur tigers(Panthera tigris altaica)at the southern edge of their range we fitted 14 tigers(6♀♀and 8♂♂)with 15 GPS-Argos collars between 2008 and 2011 in 2 study sites...To better understand the spatial structure of Amur tigers(Panthera tigris altaica)at the southern edge of their range we fitted 14 tigers(6♀♀and 8♂♂)with 15 GPS-Argos collars between 2008 and 2011 in 2 study sites:the Ussuriskii Reserve of southern Sikhote-Alin and the Land of the Leopard National Park in southwest Primorye,Russian Far East.Fixed kernel estimates of male home ranges were larger than those of female home ranges(P<0.05[mean 95%fixed kernel♀=401±205 km2;mean 95%fixed kernel♂=778±267 km2]).The home range size of females varied greatly,but on average was similar to estimates derived from earlier work further north.Low overlap of adjacent home ranges suggested that females retained exclusive territories.Real core areas of females overlapped only slightly,and remained stable over multiple years.The home ranges of adult males were smaller than those of males to the north,and in contrast to previous studies,high overlap among males indicated the absence of territoriality.Nonetheless,real core areas of males did not overlap,suggesting some spatial separation.In comparison to other tiger populations and other areas of the Russian Far East,the sex ratio in our 2 study areas was highly skewed towards males.We believe this skewed sex ratio resulted in the dissolution of territoriality of males due to an inability to defend individual females,with males resorting to scramble competition for mates.Continued monitoring of these sites to determine whether shifts in the sex ratio might result in a return to male territoriality would provide confirmation of our tentative hypothesis.展开更多
Sleeping site locations are important to free-ranging primate groups.Sites are strategically selected by primates so as to optimize security,comfort and foraging efficiency.Data were collected on the distribution of s...Sleeping site locations are important to free-ranging primate groups.Sites are strategically selected by primates so as to optimize security,comfort and foraging efficiency.Data were collected on the distribution of sleeping sites of the Yunnan snub-nosed monkey(Rhinopithecus bieti)between Sep 2005 and Sep 2006 at Gehuaqing in Baimaxueshan Nature Reserve,China.We identified 54 sleeping sites,which were used 137 times during the study period.These sleeping sites were distributed throughout the monkey group’s total home range.R.bieti preferred certain sleeping sites over others:63%of the sleeping sites were used 2 or more times in 13 months.Groups reused locations in an unpredictable long-term pattern,but avoided using the same sleeping site on consecutive nights.To reduce the time and energetic costs of travel,monkeys preferred sleeping near commonly used feeding sites.We recorded 124 feeding sites in the home range,which were used 174 times.A total of 27 sleeping sites were also feeding sites,and all remaining sleeping sites were close to feeding sites.There was a positive correlation between the intensity of use of sleeping sites and feeding sites.The present study suggests that the availability and the location of immediate sources of food is a key factor in the choice of sleeping sites.展开更多
Telemetry studies that track animals through space and time can lead to advances in scientific understanding that are vital in conservation efforts.For example,telemetry studies of the giant panda(Ailuropoda melano...Telemetry studies that track animals through space and time can lead to advances in scientific understanding that are vital in conservation efforts.For example,telemetry studies of the giant panda(Ailuropoda melanoleuca)have shed light on many aspects of panda biology,but small sample sizes in each separate study make it difficult to draw broad conclusions.To overcome this problem we conducted the first synthesis of all 5 panda telemetry studies conducted to date.Using these data we investigated patterns in 6 main topics:home range,space-use interactions,core areas,movement patterns,seasonal migration and natal dispersal.We found that panda home range sizes do not vary between 2 main mountain ranges(Qionglai and Qinling),as was previously believed.Our results also suggest that female pandas increase their movement in the mating season:a behavior typically attributed only to males.We found and summarized telemetry and genetic evidence for female natal dispersal in the giant panda.Our synthesis highlights the need for additional research relating panda behavior to human disturbance factors,and can aid future studies on giant pandas as well as other species.展开更多
The existence of a trans-boundary population of the snow leopard(Panthera uncia)that inhabits the massifs of Tsagaanshuvuut(Mongolia)-Tsagan-Shibetu(Russia)was determined through non-invasive genetic analysis of scat ...The existence of a trans-boundary population of the snow leopard(Panthera uncia)that inhabits the massifs of Tsagaanshuvuut(Mongolia)-Tsagan-Shibetu(Russia)was determined through non-invasive genetic analysis of scat samples and by studying the structure of territory use by a collared female individual.The genetic analysis included species identification of samples through sequencing of a fragment of the cytochrome b gene and individual identification using a panel of 8 microsatellites.The home range of a female snow leopard marked with a satellite Global Positioning System(GPS)collar was represented by the minimum convex polygon method(MCP)100,the MCP 95 method and the fixed kernel 95 method.The results revealed insignificant genetic differentiation between snow leopards that inhabit both massifs(minimal fixation index[FST]),and the data testify to the unity of the cross-border group.Moreover,5 common individuals were identified from Mongolian and Russian territories.This finding clearly shows that their home range includes territories of both countries.In addition,regular movement of a collared snow leopard in Mongolia and Russia confirmed the existence of a cross-border snow leopard group.These data support that trans-boundary conservation is important for snow leopards in both countries.We conclude that it is crucial for Russia to study the northern range of snow leopards in Asia.展开更多
基金This work was conducted with logistical and financial support of the Instituto Antártico Argentino.
文摘Identifying home ranges—those areas traversed by individuals in their normal foraging,mating,and parenting activities—is an important aspect of cetacean study.Understanding these ranges facilitates identification of resource use and conservation.Fin and humpback whales occur in Antarctica during the austral summer,but information regarding their home ranges is limited.Using opportunistically collected whale sighting data from eight consecutive summer seasons spanning 2010–2017,we approximate the home ranges of humpback and fin whales around Drake Passage(DRA),West of Antarctic Peninsula(WAP),South Shetland Islands(SSI),an area northwest of the Weddell Sea(WED),and around the South Orkney Islands(SOI).Approximate home ranges are identified using Kernel Density Estimation(KDE).Most fin whales occurred north and northwest of the SOI,which suggests that waters near these islands support concentrations of this species.Most humpback whales were observed around the SSI,but unlike fin whales,their distributions were highly variable in other areas.KDE suggests spatial segregation in areas where both species exist such as SOI,SSI,and WPA.Partial redundancy analysis(pRDA)suggests that the distributions of these species are more affected by spatial variables(latitude,longitude)than by local scale variables such as sea surface temperature and depth.This study presents a visual approximation of the home ranges of fin and humpback whales,and identifies variation in the effects of space and environmental variables on the distributions of these whales at different spatial scales.
基金supported by the Strategic Priority Research Program of the Chinese Academy of Sciences (XDA20050201)the National Natural Science Fund of China (31861143023).
文摘Home range is an important ecological parameter reflecting the suita bility of animal habitats.To study the size and factors influencing the home ranges of the Qinghai toad-headed lizard(Phr ynocephalus vlangalii)in different habitats,from July to September 2020,we radio-tagged and tracked 15 individuals in each of sites distributed at high(3600 m)and low(2600 m)altitudes on the Dangjin Mountain,Gansu Province,northwest China.We calculated home range size using the 100%minimum convex polygon method,and analyzed the influence of inherent lizard characteristics and external environmental factors.Our results revealed that for both high-and lowaltitude lizard populations,the sizes of home ranges were positively correlated with lizard body mass.Moreover,after eliminating the effect of body mass as a covariable,we established that the home ranges of high-altitude lizards(5255.1±1103.8 m^(2))were larger than those of the low-altitude lizards(2208.1±348.7 m^(2)).Lizards in the high-altitude population were also characterized by longer daily suitable activity times and spent significantly more time in full sunlight than those in the low-altitude population.Furthermore,the food resources for lizards in low-altitude habitats were more abundant than those in high-altitude habitats In conclusion,we established that P.vlangalii lizards inhabiting high-altitude sites had larger home ranges than conspecific lizards distributed at a lower altitude,which was associated not only with endogenous factors,such as body mass,but also with habitat-related environmental factors,such as the quality of thermal resources and availability of food.
基金We wish to thank the managers of Xiaolongmen Forestry Garden for accommodation,Zhang Jie,Sun Yue,and Dong Lu for field assistance.Financial support was provided by the National Sciences Foundation of China(Grant No.30170115).
文摘The home ranges of the Narcissus Flycatcher(Ficedula narcissina elisae)and the Yellow-rumped Fly-catcher(F.zanthopygia)are measured by radio telemetry in a subalpine forest near Beijing,China.The home range is calculated by 100%Minimum Convex Polygon(MCP),and the area varies from 2,000 to 5,000 m2.The majority of fly-catchers can be found in the bottom of valleys and the under-side of mountains.It is fairly rare for both Flycatcher species to leave their nests more than 70 m.Individuals of the species in pair-banding and nest-detecting periods have larger home ranges than those in incubation and rearing periods.The levels of canopy coverage in the home ranges of Narcissus Flycatchers are significantly higher than that of Yellow-rumped Flycatchers.There are also more tall trees and stumps in the home ranges of Narcissus Flycatchers than in that of Yellow-rumped Flycatchers.The dominant tree species in the home ranges of Narcissus Flycatchers is Dahurian Birch(Betula dahurica),whereas Manchurian Walnut(Juglans mandshurica)is the dominant tree species in the home ranges of Yellow-rumped Flycatchers.
基金Under the auscpices of Shandong Provincial Natural Science Foundation (No.ZR2020QD090)Research Funds of Beijing VMinFull Limted (No.VMF2021RS)+1 种基金National Natural Science Foundation of China (No.42176221)Seed Project of Yantai Institute of Coastal Zone Research,Chinese Academy of Sciences (No.YICE351030601)。
文摘With the loss of substantial natural wetlands in coastal zones,artificial wetlands provide alternative habitats for many shorebirds.Scientific management of artificial wetlands used by shorebirds plays an important role in maintaining the stability of shorebird population.Satellite tracking technique can obtain high-precision location information of individuals day and night,providing a good technical support for the study of quantitative relationship between waterfowls and their habitats.In this study,satellite tracking method,Remote Sensing(RS)and Geographic Information System(GIS)technology were used to analyze the activity pattern and habitat utilization characteristics of Pied Avocet during breeding period in an artificial wetland complex in the Yellow River Delta(YRD),China.The results showed that the breeding Pied Avocets had a small range of activity,with a total core and main home range of 33.10 km^(2) and 216.30 km^(2),respectively.This species tended to forage in the pond and salt pan during the day and night,respectively,with an unfixed staying time in the breeding ground.The distance between breeding ground and feeding ground was less than 6 km.It is emphasized that in addition to improving the conditions of the remaining natural habitats,effective managing artificial habitats is a priority for shorebird conservation.This research could provide reference for the management of artificial wetlands in coastal zones and supply technique support for the protection of shorebirds and their habitats,and alleviate human-bird conflicts and sustainable development of coastal zones.
基金supported by LIPU-UK(GIS and modelling work)by the Alta Murgia National Park(biotelemetry and field work)。
文摘Background:There is increasing interest in evaluating home-range overlap(or,otherwise,segregation)between bird species,and between or within bird populations,to inform spatial planning.So far,studies of home-range overlap typically make use of comparisons between pairs of individuals,populations or species,and return a matrix of pairwise overlaps(e.g.,percent overlaps).However,when the number of individuals,populations or species to be compared is elevated,an overlarge overlap matrix is difficult to interpret from an ecological viewpoint.Methods:We propose here a new,conceptually simple and computationally efficient index(general overlap index;GOI)for the ready computation within GIS of home range overlap of an arbitrarily large number(i.e.,n≥2)of individuals,populations or species.Whatever the number of home ranges to be compared,GOI always returns a single score between 0 and 100.As a case study,we applied our index to 24,074 GPS points of 10 Lesser Kestrels(Falco naumanni)in order to estimate within-colony and between-colony overlaps in two neighboring colonies in Southern Italy.Results:Within-colony overlap was elevated for both colonies(96.41%at Cassano delle Murge,n=5 individuals;81.38%at Santeramo in Colle,n=5 individuals),while between-colony overlap was low(19.12%;n=2 colonies)and,after a randomization procedure,more spatially-segregated than expected by chance.Conclusions:Modern biotelemetry offers huge amounts of data describing the space use of animal species.The use of intuitive and straightforward indices,like GOI,can be useful to promptly extract ecological information from such an amount of data(e.g.detecting change in space use over successive years,evaluating the reliability of various home-range estimators).
基金supported by the National Natural Science Foundation of China (31821001)Strategic Priority Research Program of the Chinese Academy of Sciences (XDB3100000)。
文摘A critical function of animal movement is to maximize access to essential resources in temporally fluctuating and spatially heterogeneous environments.Seasonally mediated resource fluctuations may influence animal movements,enabling them to track changing resource distributions,resulting in annual migration patterns.The conservation-dependent giant panda(Ailuropoda melanoleuca) displays seasonal movement patterns;however,the key factor driving these seasonal migration patterns remains poorly understood.Here,we used GPS tracking collars to monitor the movements of six giant pandas over a 12-year period across different elevations,and performed statistical analysis of seasonal migration directions,routes,habitat revisitation,home range overlap,first arrival events,and stability.Our results revealed a compelling pattern of seasonal migrations that facilitated the ability of the pandas to forage at the appropriate time and place to maximize nutritional intake.Our results indicated that pandas utilize spatial memory to locate reliable food resources,as evidenced by their annual return to the same or similar winter and summer home ranges and the consistently maintained percentage of home range overlap.These novel insights into giant panda foraging and movement ecology not only enhance our understanding of its ability to adapt to nutritionally poor dietary resources but also provide important information for the development of resource utilization-based protection and management strategies.
基金funded by the National Basic Research Program of China(973 Program:2007CB411600)the key project of the Natural Science Foundation of China(No.30630016)and the China Program of The Nature Conservancy.
文摘Home range studies are essential for understanding an animal’s behavioral ecology and for making wildlife conservation efficient.The home range of a group of Yunnan snub-nosed monkeys(Rhinopithecus bieti Milne-Edwards,1897)was estimated using a global positioning system collar from December 2003 to October 2004 in northern Yunnan Province,China.To measure the ranging area of the study group 1291 animal locations were fixed.Based on the 100%minimum convex polygon method,the home range size was approximately 32.8 km2;based on the grid-cell method it was approximately 17.8 km2 using a 250-m grid and 23.3 km2 using a 500-m grid.We assessed seasonal changes in the home range of this monkey population and found a different ranging pattern of from earlier studies.Daily range size was calculated as 4.80±5.81 ha(mean±standard deviation),with a range of 45.66 ha(0.01–45.67 ha).
基金the University of Buenos Aires for financial support UBACYT 20020170100235BA.
文摘Rodents are reservoirs of various types of hantavirus,some of which are agents of hantavirus pulmonary syndrome in humans.Each hantavirus is associated with a single rodent host species but successive spill-over events may eventually lead to host-switching and new species’becoming host of a given pathogen.This study aims to gain an understanding of the spatial ecology of two hantavirus-host species,Akodon azarae,and Oligoryzomys flavescens,by identifying factors modulating their home range sizes and stability,and by evaluating intra-and interspecific spatial aggregation for these species and a third one—Oxymycterus rufus—living in sympatry.For this,eleven capture-mark-recapture surveys were carried out,spanning 22 months.We found that A.azarae males have larger and more mobile home ranges than females,independently of the season.Consequently,males could likely have a more relevant role in the transmission of hantavirus because of their greater exposure both to a higher number of contacts between individuals and viral contamination of the environment.Contrasting,O.flavescens individuals showed negligible displacements of their home range through time,which could limit the range of hantavirus spread in host populations.Since O.flavescens is host to Lechiguanas hantavirus(pathogenic to humans)this result encompasses epidemiological relevance,for it may imply the existence of local foci of infection.Additionally,individuals of both species performed excursions outside their home ranges.These events could enable hantavirus spread over distances beyond the normal range of movements and lead to new hantavirus outbreaks in formerly non-infected rodent populations,favoring the persistence of the virus in nature.
基金Funding was provided by the National Natural Sciences Foundation of China (No.30070117 and 30330050)State Key Basic Research Program Plan (G2000046805).
文摘Home range and habitat use of male Reeves’s pheasant(Syrmaticus reevesii)were studied during winter of 2001~2002 and 2002~2003 in the Dongzhai National Nature Reserve,Henan Province.Results from five individuals of Reeves’s pheasant with over 30 relocations,indicated that the average size of home range was 10.03±1.17 hm^(2) by Minimum Convex Polygon method,8.60±0.35 hm^(2) by 90%Harmonic Mean Transformation method,and 9.50±1.90 hm^(2) by 95%Fixed Kernel method.It was observed that the winter range is smaller than that in the breeding season.The mean core area of the home range was found to be 1.88±0.37 hm^(2).Although the habitat composition of the core area varied greatly for individuals,a large part of the habitats used were composed of conifer and broadleaf mixed forests,masson pine forests,fir forests,and shrubs.Habitat use within the study area was non-random,while habitats within home ranges were randomly used.Habitat use was dictated by tree diameter at breast height,shrub height and coverage at 2.0 m.The proximity between forests and shrubs were also found to be important in providing refuge for the birds during winter.Recommendations for conservation management include protecting the existing habitats in Dongzhai National Nature Reserve,increasing suitable habitat for Reeves’s Pheasant through artificial plantations(e.g.firs),and restoring some parts of the large shrub area into forests.
基金supported by the project of the National Natural Science Foundation(No.3207030491,No.31770456)the Hainan Gibbon Conservation Research(No.KY-2000105-KT)。
文摘Hainan gibbons are among the world’s most critically endangered primates,with a remaining population of only 35 individuals distributed across 5 social groups in the Bawangling Branch of the Hainan Tropical Rainforest National Park,China.Habitat conversion and forest fragmentation over the past 40 years have reduced their geographical distribution by 95%.In the absence of a quantitative assessment of the availability of remaining suitable habitat,it is unclear whether this species can survive to the end of this century.We used behavioral observations,ArcGIS,remote sensing,stereo optical imagery,and MaxEnt modeling to identify patterns of Hainan gibbon range use and compare changes in the distribution of suitable forest types and areas of forest fragmentation over the past 20 years(2000–2020).The results indicate that the combined range of the 5 extant Hainan gibbon groups totaled 14.89 km2.The home range of the smallest group(Group E,3 individuals)was 1.51 km2,which likely represents the minimum home range size for this species.The remaining area of highly suitable and moderately suitable habitat totals 26.9 km2.However,habitat connectivity across the gibbon range is very low(less than 0.5),limiting the ability of Hainan gibbons to move between forest patches.The results of this study indicate that the availability of suitable habitat in Bawangling is insufficient to allow for future Hainan gibbon population growth.Therefore,immediate action must be taken to restore,reforest,and establish ecological corridors to reconnect areas of suitable habitat for these critically endangered gibbons.
基金This study was part of the long-term“Program of Studying the Amur Tiger in the Russian Far East”within the framework of the Permanent Expedition of RAS for the Study of Animals Listed of the Red Data Book of the Russian Federation and Other Highly Important Animals of the Russian Fauna as well as within the Siberian Tiger Project of the Wildlife Conservation Society(WCS-Russia).The authors are grateful to the staff of the V.L.Komarov“Ussuriskii”State Nature Reserve,FEB RAS and the Land of the Leopard National Park for fruitful support in data collection,to Dr Andrey D.Poyarkov from the A.N.Severtsov Institute of Ecology and Evolution,RAS and to Mr Alexander L.Salman for discussion and technical support.This research was made within the framework of the Program for the Study of the Amur Tiger in the Russian Far East and was supported by the Russian Geography Society。
文摘To better understand the spatial structure of Amur tigers(Panthera tigris altaica)at the southern edge of their range we fitted 14 tigers(6♀♀and 8♂♂)with 15 GPS-Argos collars between 2008 and 2011 in 2 study sites:the Ussuriskii Reserve of southern Sikhote-Alin and the Land of the Leopard National Park in southwest Primorye,Russian Far East.Fixed kernel estimates of male home ranges were larger than those of female home ranges(P<0.05[mean 95%fixed kernel♀=401±205 km2;mean 95%fixed kernel♂=778±267 km2]).The home range size of females varied greatly,but on average was similar to estimates derived from earlier work further north.Low overlap of adjacent home ranges suggested that females retained exclusive territories.Real core areas of females overlapped only slightly,and remained stable over multiple years.The home ranges of adult males were smaller than those of males to the north,and in contrast to previous studies,high overlap among males indicated the absence of territoriality.Nonetheless,real core areas of males did not overlap,suggesting some spatial separation.In comparison to other tiger populations and other areas of the Russian Far East,the sex ratio in our 2 study areas was highly skewed towards males.We believe this skewed sex ratio resulted in the dissolution of territoriality of males due to an inability to defend individual females,with males resorting to scramble competition for mates.Continued monitoring of these sites to determine whether shifts in the sex ratio might result in a return to male territoriality would provide confirmation of our tentative hypothesis.
基金supported by the project of NSFC(No.30970442,31200294)Foundation of Key Laboratory of Southwest China Wildlife Resources Conservation,Ministry of Education+10 种基金funded by grants to Cyril C.Grueter from the following institutions:Janggen-Pöhn-StiftungA.H.Schultz StiftungZürcher TierschutzZoological Society of San DiegoOffield Family FoundationAmerman FoundationPrimate ConservationG.and A.Claraz-SchenkungGoethe-StiftungJane Goodall Institute SchweizPrimate Action Fund of Conservation International.
文摘Sleeping site locations are important to free-ranging primate groups.Sites are strategically selected by primates so as to optimize security,comfort and foraging efficiency.Data were collected on the distribution of sleeping sites of the Yunnan snub-nosed monkey(Rhinopithecus bieti)between Sep 2005 and Sep 2006 at Gehuaqing in Baimaxueshan Nature Reserve,China.We identified 54 sleeping sites,which were used 137 times during the study period.These sleeping sites were distributed throughout the monkey group’s total home range.R.bieti preferred certain sleeping sites over others:63%of the sleeping sites were used 2 or more times in 13 months.Groups reused locations in an unpredictable long-term pattern,but avoided using the same sleeping site on consecutive nights.To reduce the time and energetic costs of travel,monkeys preferred sleeping near commonly used feeding sites.We recorded 124 feeding sites in the home range,which were used 174 times.A total of 27 sleeping sites were also feeding sites,and all remaining sleeping sites were close to feeding sites.There was a positive correlation between the intensity of use of sleeping sites and feeding sites.The present study suggests that the availability and the location of immediate sources of food is a key factor in the choice of sleeping sites.
文摘Telemetry studies that track animals through space and time can lead to advances in scientific understanding that are vital in conservation efforts.For example,telemetry studies of the giant panda(Ailuropoda melanoleuca)have shed light on many aspects of panda biology,but small sample sizes in each separate study make it difficult to draw broad conclusions.To overcome this problem we conducted the first synthesis of all 5 panda telemetry studies conducted to date.Using these data we investigated patterns in 6 main topics:home range,space-use interactions,core areas,movement patterns,seasonal migration and natal dispersal.We found that panda home range sizes do not vary between 2 main mountain ranges(Qionglai and Qinling),as was previously believed.Our results also suggest that female pandas increase their movement in the mating season:a behavior typically attributed only to males.We found and summarized telemetry and genetic evidence for female natal dispersal in the giant panda.Our synthesis highlights the need for additional research relating panda behavior to human disturbance factors,and can aid future studies on giant pandas as well as other species.
基金This work was executed with financial support from:the Joint Russian-Mongolian complex biological expedition RAS and MASthe Russian Geographic Society+4 种基金the Snow Leopard Conservancythe Siberian Wellness Corporationthe Program Office of WWF Mongoliathe Mongolian Center,Irbisand the Russian Foundation for Basic Research jointly with the Department of Science and Technology,India(project no.19-54-45038).
文摘The existence of a trans-boundary population of the snow leopard(Panthera uncia)that inhabits the massifs of Tsagaanshuvuut(Mongolia)-Tsagan-Shibetu(Russia)was determined through non-invasive genetic analysis of scat samples and by studying the structure of territory use by a collared female individual.The genetic analysis included species identification of samples through sequencing of a fragment of the cytochrome b gene and individual identification using a panel of 8 microsatellites.The home range of a female snow leopard marked with a satellite Global Positioning System(GPS)collar was represented by the minimum convex polygon method(MCP)100,the MCP 95 method and the fixed kernel 95 method.The results revealed insignificant genetic differentiation between snow leopards that inhabit both massifs(minimal fixation index[FST]),and the data testify to the unity of the cross-border group.Moreover,5 common individuals were identified from Mongolian and Russian territories.This finding clearly shows that their home range includes territories of both countries.In addition,regular movement of a collared snow leopard in Mongolia and Russia confirmed the existence of a cross-border snow leopard group.These data support that trans-boundary conservation is important for snow leopards in both countries.We conclude that it is crucial for Russia to study the northern range of snow leopards in Asia.