Migration pattern of a population of Barn Swallows(Hirundo rustica)breeding in East Asian tropical region

Birds exhibit a high degree of migratory diversity,which is influenced by various ecological factors and life history strategies.Conducting studies on tropical bird migration,of which research is scarce,and comparing it with temperate birds can enhance our understanding of bird migration behaviour and its underlying mecha-nisms.In this study,we explored the migration behaviour of a breeding population of the Barn Swallow(Hirundo rustica)in Zhanjiang,southern China,a region located in the northern tropics,using light-level geolocators.From 2021 to 2023,we deployed geolocators on 92 breeding swallows and retrieved geolocators successfully from 23 individuals.These swallows all exhibited migratory behaviour,and wintering on various islands in Southeast Asia.They displayed sex differences in their wintering locations.All males concentrated in Borneo,while females primarily chose Borneo but also dispersed to the Philippines,South China Sea,and Vietnam for wintering.The studied swallow population adopted a seasonal migration pattern of“indirect in autumn,direct in spring”,bypassing the ecological barrier of the South China Sea in autumn and tending to directly cross it in spring migration.Moreover,the distance and duration of autumn migration was significantly longer than those of the spring migration.Compared to temperate Barn Swallows,the Barn Swallow population breeding in Zhanjiang adopts a pattern of“intra-tropical migration”and initiates autumn migration earlier.The formation of their migration pattern may be limited by ecological and physiological factors.

Population genomic data reveal low genetic diversity,divergence and local adaptation among threatened Reeves's Pheasant(Syrmaticus reevesii)

Population genomic data could provide valuable information for conservation efforts;however,limited studies have been conducted to investigate the genetic status of threatened pheasants.Reeves’s Pheasant(Syrmaticus reevesii)is facing population decline,attributed to increases in habitat loss.There is a knowledge gap in understanding the genomic status and genetic basis underlying the local adaptation of this threatened bird.Here,we used population genomic data to assess population structure,genetic diversity,inbreeding patterns,and genetic divergence.Furthermore,we identified candidate genes linked with adaptation across the current distribution of Reeves’s Pheasant.The present study assembled the first de novo genome sequence of Reeves’s Pheasant and annotated 19,458 genes.We also sequenced 30 individuals from three populations(Dabie Mountain,Shennongjia,Qinling Mountain)and found that there was clear population structure among those populations.By comparing with other threatened species,we found that Reeves’s Pheasants have low genetic diversity.Runs of homozygosity suggest that the Shennongjia population has experienced serious inbreeding.The demographic history results indicated that three populations experienced several declines during the glacial period.Local adaptative analysis among the populations identified 241 candidate genes under directional selection.They are involved in a large variety of processes,including the immune response and pigmentation.Our results suggest that the three populations should be considered as three different conservation units.The current study provides genetic evidence for conserving the threatened Reeves’s Pheasant and provides genomic resources for global biodiversity management.

Corrigendum to“Migration pattern of a population of Barn Swallows(Hirundo rustica)breeding in East Asian tropical region”[Avian Res.15(2024)100192]

The authors regret that the caption of Fig.4 should be replaced as below.

Achievements,challenges,and recommendations for waterbird conservation in China's coastal wetlands

China’s coastal wetlands provide breeding,migration stopover,and wintering habitats for about 230 waterbird species,which is more than a quarter of all waterbirds in the world.Large-scale and high intensity human activities have resulted in serious loss and degradation of coastal wetlands over the past half century,causing population declines in many waterbirds.Through a literature review and expert surveys,this article reviews conservation measures taken in recent decades to protect waterbirds in China’s coastal wetlands and provides recommendations for future conservation action from three aspects:policy and administration,habitat conservation and management,and multiparty participation.Over the past decades,many conservation legislation,regulations and action plans at the national level and more site-specific measures and interventions have been implemented,with notable improvement in the effectiveness in policy making and multi-stakeholder participation.Accordingly,some threats to waterbirds have been mitigated and many key sites for waterbirds have been designated as strictly protected nature reserves.However,some critical issues still remain,mostly related to habitat conservation and management,such as coastal wetland restoration,control of invasive Spartina alterniflora,control of environmental pollution,and improvement of artificial habitat quality.We highlight that protecting natural tidal wetlands and improving habitat quality are critical for the conservation of coastal waterbirds,especially those highly dependent on the intertidal wetlands.China has demonstrated strong commitment to ecological conservation and restoration for the future,in terms of both funding and policies for biodiversity and wetland ecosystems.It is important that this commitment to conserve coastal waterbirds is supported continuously by science-and evidence-based decisions and actions.

Corrigendum to“Achievements,challenges,and recommendations for waterbird conservation in China's coastal wetlands”[Avian Res.14(2023)100123]

The authors regret that Fig.1 and its caption should be replaced as below.

Using non-destructive sampling to evaluate the population genomic status of captive Brown Eared Pheasants

Evaluating the genetic status of threatened species is an essential task in conservation genetics.However,the genetic status of threatened species has been mostly evaluated through techniques that fail to estimate genetic diversity at the whole genomic level.Next generation sequencing can meet this demand,but high quality samples such as blood or muscle tissues are required.However,it is difficult to collect such samples from threatened species because sampling work may impact their health.Therefore,it is essential to design a workflow to evaluate the whole genomic status of threatened species using non-destructive sampling.Even though non-destructive sampling has been used in traditional barcoding technique,the barcoding technique cannot evaluate the whole genomic status.Brown Eared Pheasant(Crossoptilon mantchuricum)is an endangered species,with captive populations maintained in Taiyuan Zoo,China,and Europe.However,the genetic diversity,inbreeding pattern,and mutation load of these two populations are unclear.To uncover the genetic status of these two captive populations,we applied 2b-RAD technology to evaluate the genomic status of these populations using feathers as samples.The feathers could be collected by non-destructive sampling.The results indicate that the Taiyuan Zoo population has a lower genetic diversity and higher inbreeding coefficient than the European population.The Taiyuan Zoo population has lethal mutations when homozygous.The current project uses a non-destructive sampling technique to evaluate the whole genomic status of the two captive populations,providing a paradigm for conservation genetics,which will facilitate the development of conservation biology.

Predicting the non-breeding distributions of the two Asian subspecies of Black-tailed Godwit using morphological information

Until recently,Limosa limosa melanuroides was thought to be the only subspecies of Black-tailed Godwit in the East Asian-Australasian Flyway.For this reason,all previous occurrences and counts of Black-tailed Godwits in the flyway have been assigned to melanuroides.However,a larger-bodied subspecies,bohaii,has recently been discovered in the flyway.As a result,the occurrence of Black-tailed Godwits in the flyway needs to be reconsidered such that the specific distribution of each subspecies becomes known.To this end,we developed a simple discriminant function to assign individuals to subspecies based on their bill and wing length.Cross-validation with individuals known to be bohaii or melanuroides,based on molecular analysis,showed the developed function to be 97.7%accurate.When applied to measurements of godwits captured at 22 sites across 9 countries in East-Southeast Asia and Australia,we found that bohaii and melanuroides occurred at most sites and overlapped in their distribution from Kamchatka to Australia.We examined photos from all along the flyway to verify this surprising result,confirming that both subspecies co-occur in most locations.Based on these results,we hypothesise that bohaii and melanuroides from the west of their breeding ranges mostly migrate over Chinese mainland.Birds of both subspecies from the east of their ranges are expected to migrate along the Pacific Ocean.We encourage ringing groups in East-Southeast Asia and Australia to use this simple method to keep adding knowledge about Black-tailed Godwits in the East Asian-Australasian Flyway.

Research advances of Galliformes since 1990 and future prospects

Background: Galliformes are widely distributed throughout the world and economically important to humans as domesticated animals or gamebirds. They are at a unique position for advancing knowledge and techniques of wildlife conservation as the barometer of the status of applied ecology. Populations of many galliform species have declined mainly due to habitat loss and over-hunting. An assessment of knowledge of Galliformes could help to provide guidelines for future research and conservation strategies.Methods: Using the Web of Science search engine, we conducted a literature review of galliform-related articles published from 1990 to 2016. We used the "research area" option to filter articles focused on the zoology, environmental sciences ecology, biodiversity conservation, forestry, behavioral sciences, reproductive biology, biochemistry and molecular biology, cell biology, genetics and heredity, evolutionary biology, physiology and developmental biology. We then checked duplication based on the title, abstract and full text. In addition, we examined the reference lists of selected studies to include the publications that were missed by above searching.Results: We retained 1874 articles related to the Galliformes from the initial 243,128 publications that were found. About 91.4% focused on one or two species, and 85.0% were conducted within a short duration, typically 1–2 years. The majority of the articles concentrated on macroscopic ecology(55.5%), mainly focusing on habitat selection or habitat use. With recent advances of molecular biology, the studies of taxonomy and phylogenetics rose quickly in last two decades. The study of physiology and biochemistry was no longer limited to simple description but expanded to the mechanisms of phenotype and micro-evolutionary potential. An additional area receiving increasing attention is the conservation of Galliformes, with the assessment of the conservation status and conservation management effectiveness of Galliformes(e.g. species diversity and genetic diversity) becoming the focus.Conclusions: The studies on Galliformes have made great achievements since 1990, but there are still gaps, particularly in macroscopic ecology, molecular genetics, and conservation. There is an urgent need to enhance long-term monitoring and analysis of population dynamics, and applying different disciplines to galliform conservation. Moreover, life history information of many galliform species is still lacking, which has hindered conservation efforts and effectiveness. In addition, multidiscipline studies and new technologies are not common for galliform studies, and should be encouraged.

Nest predators, nest-site selection and nest success of the Emei Shan Liocichla(Liocichla omeiensis), a vulnerable babbler endemic to southwestern China

Background: The Emei Shan Liocichla(Liocichla omeiensis) is a globally vulnerable babbler, endemic to southwestern China. We investigated its nest predators, nest-site selection and nest success at the Laojunshan National Nature Reserve in Sichuan, China in order to identify the precise nesting-habitat requirements of the species, and to test whether the nest-site-selection cues, preferred by the Emei Shan Liocichla, are positively associated with nest success.Methods: We used infrared cameras to determine nest predators. We compared the microhabitat attributes between nest and random sites, as well as successful and failed nests. We used Binary Logistic Regression to determine the most important variables affecting nest-site selection of the Emei Shan Liocichla. We used the nest survival analysis in Program MARK to estimate daily nest survival rates(DSR). Nest success was calculated using the Mayfield method.Results: In total 56 nests were found. The DSR for all nests that contained at least one egg was 0.9564 ± 0.0091(95 % CI 0.9346–0.9711)(n = 40), while the total nest success was 27.5 %. We identified four categories of predators in 10 nest predation events, i.e. squirrels(n = 5), snakes(n = 3), raptors(n = 1) and wasps(n = 1). We found that:(1) nest predation was the primary reason for nest failure of the Emei Shan Liocichla,(2) tree cover, bamboo cover, liana abundance and distance to forest edge or gap were the most important variables affecting nest-site selection of this species, and(3) the nest-site-selection variables we measured appeared not to be positively associated with nest success.Conclusions: Our findings suggest that the Emei Shan Liocichla tended to select nest sites near forest edges or gaps with good concealment and that nest-site selection by this species was nonrandom but not necessarily adaptive. Reducing forest-edge development and protecting bamboo stands should be effective for conservation of this species.

Autumn migration routes of fledgling Chinese Egrets(Egretta eulophotes)in Northeast China and their implications for conservation

The Chinese Egret(Egretta eulophotes)is a globally threatened bird species living on the coast and islands of Liaoning,northeastern China,mainly in summer.To further protect the breeding population of Chinese Egrets,it is important to understand the current protection status of their distribution sites at pre-migration period and migration routes.Thirty-three individuals were tagged with satellite transmitters at Fantuo Island in Changhai and Xingren Island in Zhuanghe,Liaoning Province,northeastern China,in July of 2016,2017,and 2018,to identify important distribution sites during the pre-migration period,as well as detailed migration routes.The results showed that coastal mudflats in Liaoning and the west coast of North Korea were important feeding and roosting sites for fledgling Chinese Egrets from August to September.The home range sizes in August were significantly larger than in September.The eastern coast from Shandong to Guangdong,as well as Taiwan,China,and Manila Bay and Galileo Islands in the Philippines,were important stopover sites during fall migration.Specifically,we found that the egrets’autumn migration could be divided into four routes,i.e.,sea-crossing migration(SCM),coastal migration(CM),inland migration(IM),and mixed migration(MM).The migration distance,timing,speed,and straightness of the four routes also differed.The SCM routes were the straightest,and had the fastest migration speed and shortest travel time,while the IM routes had the lowest straightness and speed,and the longest duration.Manila Bay and Bohol Island in the Philippines,the west coast of Tanintharyi in Myanmar,and the Zengwun River Estuary in Taiwan,China,were wintering sites.Our findings on the key distribution sites along pre-migration and fall migration routes,including some stopover sites,have important implications for the conservation of and global action plan development for the vulnerable Chinese Egret.

Seasonal and population differences in migration of Whimbrels in the East Asian–Australasian Flyway

Background:Conserving migratory birds is challenging due to their reliance on multiple distant sites at different stages of their annual life cycle.The concept of“flyway”,which refers to all areas covered by the breeding,nonbreeding,and migrating of birds,provides a framework for international cooperation for conservation.In the same flyway,however,the migratory activities of the same species can differ substantially between seasons and populations.Clarifying the seasonal and population differences in migration is helpful for understanding migration ecology and for identifying conservation gaps.Methods:Using satellite‑tracking we tracked the migration of Whimbrels(Numenius phaeopus variegatus)from nonbreeding sites at Moreton Bay(MB)and Roebuck Bay(RB)in Australia in the East Asian-Australasian Flyway.Mantel tests were used to analyze the strength of migration connectivity between the nonbreeding and breeding sites of MB and RB populations.Welch’s t test was used to compare the migration activities between the two populations and between northward and southward migration.Results:During northward migration,migration distance and duration were longer for the MB population than for the RB population.The distance and duration of the first leg flight during northward migration were longer for the MB population than for the RB population,suggesting that MB individuals deposited more fuel before departing from nonbreeding sites to support their longer nonstop flight.The RB population exhibited weaker migration connectivity(breeding sites dispersing over a range of 60 longitudes)than the MB population(breeding sites concentrating in a range of 5 longitudes in Far Eastern Russia).Compared with MB population,RB population was more dependent on the stopover sites in the Yellow Sea and the coastal regions in China,where tidal habitat has suffered dramatic loss.However,RB population increased while MB population decreased over the past decades,suggesting that loss of tidal habitat at stopover sites had less impact on the Whimbrel populations,which can use diverse habitat types.Different trends between the populations might be due to the different degrees of hunting pressure in their breeding grounds.Conclusions:This study highlights that conservation measures can be improved by understanding the full annual life cycle of movements of multiple populations of Whimbrels and probably other migratory birds.

Characterization of novel microsatellite markers of the Emei Shan Liocichla using restriction site-associated DNA sequencing

Background:The Emei Shan Liocichla(Liocichla omeiensis) is an endemic bird species to southwestern China with a small geographic range. However, little was known about the genetic status of this threatened species.Methods:We applied restriction-site-associated DNA sequencing(RAD-Seq) for rapid mass identification of microsatellite markers of the Emei Shan Liocichla.Results:A total of 11,564 microsatellite sequences were obtained, 600 random loci were designed for screening and 24 polymorphic microsatellite loci were selected for further validation. The average allele number, average observed heterozygosity and average expected heterozygosity were relatively low in our samples, which were 6.08, 0.6618 and 0.7048, respectively, indicating that the Emei Shan Liocichla might have lost some genetic diversity. Further analyses suggested that the populations distributed on two mountains(Daxiangling and Xiaoliangshan) showed a modest degree of genetic differentiation.Conclusions:These novel microsatellite markers provided valuable preliminary knowledge regarding the genetic status of the Emei Shan Liocichla and can be useful in further studies, as well as in the management and conservation of this species.

Saltmarsh vegetation and social environment influence flexible seasonal vigilance strategies for two sympatric migratory curlew species in adjacent coastal habitats

Background:Animals need to adjust their vigilance strategies when foraging between physically contrasting veg-etated and non-vegetated habitats.Vegetated habitats may pose a greater risk for some if vegetation characteristics function as a visual obstruction but benefit others if they serve as protective shelter.Variation in group size,presence of similar species,along with variation in environmental conditions and anthropogenic disturbance can also influence vigilance investment.Methods:In this study,we quantified the vigilance behaviour of two large-bodied,sympatric migratory curlew species-Far Eastern Curlew(Numenius madagascariensis)and Eurasian Curlew(N.arquata)-in vegetated Suaeda salsa saltmarsh and non-vegetated mudflat habitat in Liaohekou National Nature Reserve,China.We used linear mixed models to examine the effects of habitat type,season,tide time,flock size(conspecific and heterospecific),and human disturbance on curlew vigilance investment.Results:Both species spent a higher percentage of time under visual obstruction in S.salsa habitat compared to mudflat habitat but in response,only Far Eastern Curlew increased their percentage of vigilance time,indicating that visual obstruction in this habitat is only a concern for this species.There was no evidence that S.salsa vegetation served as a form of cryptic background colouration since neither species decreased their vigilance effect in S.salsa habitat in spring compared to the autumn migration season.The effect of curlew social environment(i.e.flock size)was habitat dependent since percentage of vigilance time by curlews in saltmarsh increased with both the number of individual curlews and number of other birds present,but not in mudflat habitat.Conclusions:We conclude that both migratory curlew species exhibit a flexible vigilance adjustment strategy to cope with the different environmental and social conditions of adjacent and sharply contrasting coastal habitats,and that the trade-off between the risks of foraging and the abundance of prey may be a relatively common phenom-enon in these and other shorebird populations.

Evaluation of nest site preferences of a nest dismantler,the Hair-crested Drongo(Dicrurus hottentottus) in Dongzhai National Nature Reserve of central China

Background:The Hair-crested Drongo(Dicrurus hottentottus) exhibits a unique nest-dismantling behavior after the fledging of the young.One hypothesis explaining this behavior is dismantling one's own nest may reduce potential competition for nest sites in the following breeding season because suitable breeding habitat might be limited,and sites are often reused.Methods:By comparing the habitat features at nest and random locations,we determined the nest habitat preference of the Hair-crested Drongo within Dongzhai National Nature Reserve,Henan,China.We also compared habitat features with nesting success to determine if any trends could be detected.Results:We found that nest tree height,diameter at breast height,live crown ratio,tree rank,and presence of overstory were significantly higher at nesting locations than random locations;slope,leaf litter cover percentage and depth,presence of understory and midstory,and number of trees per hectare were significantly lower at nest sites than random sites.Drongos preferred to use some tree species,such as Metasequoia glyptostroboides,Castanea mollissima,and Pterocarya stenoptera for nesting.Failed nests were often associated with habitat with higher percentage of leaf litter on the ground.Conclusion:Our data support that selection of nest sites does occur for this species at this site and therefore support the hypothesis that breeding habitat limitation could be one of the driving forces for the development of the nestdismantling behavior in this species.

Multilocus phylogeography and ecological niche modeling suggest speciation with gene flow between the two Bamboo Partridges

Background:Understanding how species diversify is a long-standing question in biology.The allopatric speciation model is a classic hypothesis to explain the speciation process.This model supposes that there is no gene flow during the divergence process of geographically isolated populations.On the contrary,the speciation with gene flow model supposes that gene flow does occur during the speciation process.Whether allopatric species have gene flow during the speciation process is still an open question.Methods:We used the genetic information from 31 loci of 24 Chinese Bamboo Partridges(Bambusicola thoracicus)and 23 Taiwan Bamboo Partridges(B.sonorivox)to infer the gene flow model of the two species,using the approxi-mate Bayesian computation(ABC)model.The ecological niche model was used to infer the paleo-distribution during the glacial period.We also tested whether the two species had a conserved ecological niche by means of a back-ground similarity test.Results:The genetic data suggested that the post-divergence gene flow between the two species was terminated before the mid-Pleistocene.Furthermore,our ecological niche modeling suggested that their ecological niches were highly conserved,and that they shared an overlapping potential distribution range in the last glacial maximum.Conclusions:The allopatric speciation model cannot explain the speciation process of the two Bamboo Partridges.The results of this study supported a scenario in which speciation with gene flow occurring between the allopatric species and have contributed to our understanding of the speciation process.

Egg-spot matching in common cuckoo parasitism of the oriental reed warbler: effects of host nest availability and egg rejection

Background: The success of cuckoo parasitism is thought to depend largely on the extent of egg matching between cuckoo and host eggs, since poor-matching cuckoo egg would lead to more frequent egg rejection by the host. In this study, we investigated how egg-spot matching between the Common Cuckoo(Cuculus canorus) and its host, the Oriental Reed Warbler(Acrocephalus orientalis) is affected by the local parasitism rate, nest availability in breeding synchronization and egg rejection.Methods: We used the paired design of parasitized and their nearest non-parasitized nests where breeding occurred simultaneously to compare egg-spot matching. The image analysis was used to compare four eggshell pattern variables, namely spot size, density, coverage on the different areas of egg surface, and the distribution on the whole egg surface. Egg recognition experiments were conducted to test the effect of egg spots on egg rejection by the host.Results: Our results show that much better matching in almost all spot parameters tested on the side of the egg and the spot distribution on the whole egg occurred in parasitized nests than in non-parasitized nests. Matching of spot density between cuckoo and host eggs in parasitized nests increased with the synchronization between temporal availability of nests and the egg-laying period of female cuckoos. Egg recognition experiments in which the warbler eggs were deliberately painted with extra spots led to a significantly higher egg rejection rate(78.3%) than of unpainted eggs.Conclusion: Our data suggest that both the high temporal encounter rate between cuckoo and warbler nests as well as the high egg rejection ability of the host are important factors for egg-spot matching of the cuckoos.

Research activity does not affect nest predation rates of the Silver-throated Tit,a passerine bird building domed nests

Background:Research activities have often been thought to potentially influence avian nesting success by increasing nest predation rates.Although recent studies of species building open nests and cavity nests suggest that research disturbance does not generally induce nest predation,whether it is also the case in species building domednests remains unknown.In birds,domed-nest species exist in about half of the passerine families,and research disturbance to the domed nests may differ from that to the nests of other types for their different nest structures.Methods:We investigated if research activities affected nest predation rate by analyzing the relationships of the daily nest survival rate with the research activities at the egg and nestling stages of a domed-nest species,the Silverthroated Tit(Aegithalos glaucogularis).Results:Our results showed that nest daily survival rate was significantly affected by the laying date and nest age during the egg stage,and by the hatching date only during the nestling stage.By contrast,there were no significant effects of research activities,in terms of visiting nests and filming nests,on the nest survival of the Silver-throated Tit at both the egg and nestling stages.Conclusions:Our results coincide with the findings in species building other types of nests that research activities do not always have negative effects on avian nesting success.

The allocation between egg size and clutch size depends on local nest survival rate in a mean of bet-hedging in a shorebird

Background:The allocation of resources between offspring size and number is a central question of life-history theory.Although several studies have tested the existence of this trade-off,few studies have investigated how environmental variation influences the allocation of resources to offspring size and offspring number.Additionally,the relationship between population dynamics and the offspring size and number allocation is far less understood.Methods:We investigate whether resource allocation between egg size and clutch size is influenced by the ambient temperature and whether it may be related to apparent nest survival rate.We measured 1548 eggs from 541 nests of two closely related shorebird species,the Kentish Plover(Charadrius alexandrinus)and the White-faced Plover(C.dealbatus)in China,in four populations that exhibit contrasting ambient environments.We weighed females,monitored nest survival,and calculated the variance of ambient temperature.Results:Although we found that egg size and clutch size were all different between the four breeding populations,the reproductive investment(i.e.total clutch volume)was similar between populations.We also found that populations with a high survival rate had relatively larger eggs and a smaller clutch than populations with a low nest survival rate.The latter result is in line with a conservative/diversified bet-hedging strategy.Conclusions:Our findings suggest that plovers may increasing fitness by investing fewer,larger or many,small according local nest survival rate to make a similar investment in reproduction,and thereby may have an impact on population demography.

Identification of annual routines and critical stopover sites of a breeding shorebird in the Yellow Sea,China

Pied Avocets(Recurvirostra avosetta)are common migratory shorebirds in the East Asian–Australasian Flyway.From 2019 to 2021,GPS/GSM transmitters were used to track 40 Pied Avocets nesting in northern Bohai Bay to identify annual routines and key stopover sites.On average,southward migration of Pied Avocets started on 23 October and arrived at wintering sites(mainly in the middle and lower reaches of the Yangtze River and coastal wetlands)in southern China on 22 November;northward migration started on 22 March with arrival at breeding sites on 7 April.Most avocets used the same breeding sites and wintering sites between years,with an average migration distance of 1124 km.There was no significant difference between sexes on the migration timing or distance in both northward and southward migration,except for the departure time from the wintering sites and winter distribution.The coastal wetland of Lianyungang in Jiangsu Province is a critical stopover site.Most individuals rely on Lianyungang during both northward and southward migration,indicating that species with short migration distances also heavily rely on a few stopover sites.However,Lianyungang lacks adequate protection and is facing many threats,including tidal flat loss.We strongly recommend that the coastal wetland of Lianyungang be designated as a protected area to effectively conserve the critical stopover site.

An unusual homing behavior found in the Sichuan Partridge during the early brooding period

In this study,we report an unusual homing behavior of the Sichuan Partridge(Arborophila rufipectus)at the Laojunshan National Nature Reserve,Sichuan Province,China.Hen Sichuan Partridges led the chicks back to the nests where they hatched in the evening and roosted there over night.This behavior lasted 6.7±4.3 nights(range=1–15;n=13)after the chicks hatched.At this stage,the hens became very vigilant to predators and human disturbance.If disturbed,they often abandoned the nests immediately and no longer returned thereafter.The ambient temperature at night during the early brooding period of Sichuan Partridge at our study site was^12.4°C.Our findings suggest that hen Sichuan Partridges may make trade-offs between nest predation risks versus the thermoregulatory needs of their young.