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Abstract Studies show that birds cognize human disturbance as a potential predation risk. However, the responses of breeding birds to long‐term continuous disturbance by research activities and whether researcher disturbance affects the fitness of target species remain poorly understood. In this study, we used field observation data collected over 6 years to assess the potential impacts of research activities on nest‐site selection and nest success of the Emei Shan Liocichla (Liocichla omeiensis), a vulnerable babbler species endemic to Southwest China. Our results showed that Emei Shan Liocichlas tended to nest in taller nesting plants or the higher parts of nesting plants to increase nest‐site height following researcher disturbance. The average height of Emei Shan Liocichla nests increased by 52.2% over the 6‐year study period, from 129.8 ± 9.2 cm in 2009 (n = 11) to 197.5 ± 12.1 cm in 2015 (n = 18). While some pairs adopted a different strategy, placing their nests in Rosaceae plants with thorns instead of the bamboo Chimonobambusa szechuanensis (the favored nesting plant of the Emei Shan Liocichla) under high interference pressure, which made it more difficult for researchers to approach their nests. There were no significant differences both in clutch size and nest success between the low‐ and high‐disturbance groups. The study revealed the behavioral response pattern of breeding Emei Shan Liocichlas to researcher disturbance, which will contribute to conservation of this threatened songbird and the knowledge of reproductive strategies of birds. Developing specific guidelines for fieldwork and strengthening visitor management within its core habitat of Emei Shan Liocichla during breeding period should be considered.

Abstract 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 approximate 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 background 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.

Abstract In this study, we reported a case of insect‐plant‐bird interactions under climate warming. With a succession of warmer winters from 2013 to 2015, successive outbreaks of the moth Pantana phyllostachysae, a common defoliator for most bamboo species, occurred in the Wawushan Nature Reserve of Southwest China, leading to a rapid altitudinal range expansion from 1650 to 2050 m in P. phyllostachysae. The bamboo Chimonobambusa szechuanensis that is largely distributed at moderate altitudes consequently suffered much loss. Accumulated infested area of C. szechuanensis within the reserve during the 3 years covered ~90% of the suitable breeding habitats of Emei Shan Liocichla Liocichla omeiensis, a threatened songbird preferring to nest in the bamboo, which led to diversified nesting‐plant selection and a significant reduction in nesting success of the babbler. Our findings provide new evidence of the plasticity of avian breeding behavior, and of the impact of climate change on ecological communities through multi‐species interactions. The study has important conservation implications.

Abstract 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.

Abstract 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.

In some oscine birds, individually distinctive vocalisations are thought to be more pronounced allowing individual recognition based on songs. In this study, we explore individual identification in the songs of male Emei Shan Liocichla, a vulnerable babbler that inhabits dense vegetation. We recorded territorial songs of male Emei Shan Liocichla from Laojunshan National Nature Reserve during the breeding season of 2016, in southern Sichuan, China. We used three methods to compare the acoustic difference among and within individuals. The results demonstrated that male Emei Shan Liocichlas had individually distinct songs and can be used to identify individuals. We also found that 4 to 5 songs were relatively certain of an individual identity. Our findings indicated that individual distinctiveness by vocalisation was reliable in the Emei Shan Liocichla. Monitoring song therefore provides a potential method to follow individuals in the field and thus facilitate ecological research of this secretive species. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Host-associated microbiotas are known to influence host health by aiding digestion, metabolism, nutrition, physiology, immune function, and pathogen resistance. Although an increasing number of studies have investigated the avian microbiome, there is a lack of research on the gut microbiotas of wild birds, especially endangered pheasants. Owing to the difficulty of characterizing the dynamics of dietary composition, especially in omnivores, how the gut microbiotas of birds respond to seasonal dietary changes remains poorly understood. The Sichuan partridge (Arborophila rufipectus) is an endangered pheasant species with a small population endemic to the mountains of southwest China. Here, 16S rRNA sequencing and Tax4Fun were used to characterize and compare community structure and functions of the gut microbiota in the Sichuan partridges across three critical periods of their annual life cycle (breeding, postbreeding wandering, and overwintering). We found that the microbial communities were dominated by Firmicutes, Proteobacteria, Actinobacteria, and Cyanobacteria throughout the year. Diversity of the gut microbiotas was highest during postbreeding wandering and lowest during the overwintering periods. Seasonal dietary changes and reassembly of the gut microbial community occurred consistently. Composition, diversity, and functions of the gut microbiota exhibited diet-associated variations, which might facilitate host adaptation to diverse diets in response to environmental shifts. Moreover, 28 potential pathogenic genera were detected, and their composition differed significantly between the three periods. Investigation of the wild bird gut microbiota dynamics has enhanced our understanding of diet-microbiota associations over the annual life cycle of birds, aiding in the integrative conservation of this endangered bird. IMPORTANCE Characterizing the gut microbiotas of wild birds across seasons will shed light on their annual life cycle. Due to sampling difficulties and the lack of detailed dietary information, studies on how the gut microbiota adapts to seasonal dietary changes of wild birds are scarce. Based on more detailed dietary composition, we found a seasonal reshaping pattern of the gut microbiota of Sichuan partridges corresponding to their seasonal dietary changes. The variation in diet and gut microbiota potentially facilitated the diversity of dietary niches of this endangered pheasant, revealing a seasonal diet-microbiota association across the three periods of the annual cycle. In addition, identifying a variety of potentially pathogenic bacterial genera aids in managing the health and improving survival of Sichuan partridges. Incorporation of microbiome research in the conservation of endangered species contributes to our comprehensive understanding the diet-host-microbiota relationship in wild birds and refinement of conservation practices. [ABSTRACT FROM AUTHOR]