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 Nati...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.展开更多
The Great Spotted Woodpecker Dendrocopos major （L.）, one of the natural predators of Anoplophora glabripennis （Motsch.） （Coleoptera： Cerambycidae）, is resident to Wulate Qianqi County of the Inner Mongolia and ...The Great Spotted Woodpecker Dendrocopos major （L.）, one of the natural predators of Anoplophora glabripennis （Motsch.） （Coleoptera： Cerambycidae）, is resident to Wulate Qianqi County of the Inner Mongolia and widely found in shelter plantations. In August 2005 and 2006, 174 and 153 nest-cavities of Great Spotted Woodpeckers were found respectively in Wulate Qianqi County and 22 breeding nest-cavities were investigated in 2007. The results showed that mostly willow species were selected for nesting by the Great Spotted Woodpecker, but mature poplar trees also could be chosen. Nest cavities were often found with a protuberance above the cavity entrance or with a downward sloping gradient, or both. The selection of the height of the nest-cavity height was not significant. The vertical diameter of the nest-cavity entrance （VDE） and the horizontal diameter of the nest-cavity entrance （HDE） ranged from 5.0 to 5.8 cm. The results also indicated that the compass orientation of more than 60% of nest-cavities were towards the north, northeast and east. This study suggests a convergence of some nest-cavity characteristics of the Great Spotted Woodpecker in shelter plantations and will help us to make artificial nest for conserving the woodpecker and, as well, use the bird for controlling pests.展开更多
Background:Information pertaining to nest-site fidelity and breeding dispersal over successive years can help to better our understanding of how birds respond to nest predation.Methods:By using mist nets and tracking ...Background:Information pertaining to nest-site fidelity and breeding dispersal over successive years can help to better our understanding of how birds respond to nest predation.Methods:By using mist nets and tracking the color banded individuals,we investigated nest-site fidelity and breeding dispersal by Common Tailorbirds(Orthotomus sutorius)throughout a year and between successive years in 2017–2018.Results:The present study showed that Common Tailorbirds could produce up to four clutches per breeding season.When multiple broods were produced within a year,breeding pairs remained together,and the nest rebuilding rate was up to 92.2%,with only four cases(7.8%)in which birds reused their old nests.The dispersal distance between the nests during multiple breeding was found to be 10.0±10.5 m,and nest-site fidelity within the same year was 90.0%.By the second year of breeding,76.2%of individuals remained in the original breeding pairs,while for those that did switch partners,the females remained in the nest from the previous year and paired with new males.The dispersal distance between years was 26.5±41.9 m,and nest-site fidelity between different years was 80.1%.There was no significant difference between within-year and between-year dispersal distances.Moreover,there was no significant difference in the dispersal distance of rebuilt nests between birds that had experienced nest predation and those that had not.Conclusions:Our findings suggest that Common Tailorbirds maintain a high degree of fidelity to mates and nestsites,and nest predation had no significant effect on territorial changes or breeding dispersal distance between each breeding attempt.展开更多
Nest site selection is a vital component of bird reproduction success,and an adaptive behavior conducted to decrease nest predation risk with avoiding external disturbances.Understanding patterns of nest site selectio...Nest site selection is a vital component of bird reproduction success,and an adaptive behavior conducted to decrease nest predation risk with avoiding external disturbances.Understanding patterns of nest site selection can provide insights into how species adapt to changes in their habitat and has important conservation implications.In this study,we used microhabitat variables and multi-scale data with a field survey of nest occurrence to determine nest site selection patterns and adaptive strategies of the breeding Oriental Storks(Ciconia boyciana)in different nest areas.Results demonstrate that the nest site microhabitat characteristics of the breeding Oriental Storks significantly differed among the three nesting areas,and nest height was higher in the middle and lower Yangtze River floodplain than in the Northeast China and Bohai Bay nest areas.The food resources and intensity of human disturbance had the greatest effects on the nest site selection of the breeding Oriental Storks.The intensity of human disturbance was positively correlated with the nest height of the breeding Oriental Storks in Bohai Bay and the middle and lower Yangtze River floodplain;however,nest height decreased with the abundance of food resources in the Northeast China nest area.Our findings indicate that the nest site selection patterns of Oriental Storks showed flexible adaptive strategies.In safer environments,nests were lower and closer to food resources,which allows parent storks to invest more in the nestlings.However,in areas where human activity was intense,nests were higher to ensure the safety of their offspring.Some measures that could be taken to improve the breeding habitat of Oriental Storks include increasing the percentage of wetland areas in nesting areas to enhance food resources availability and setting artificial nests at suitable heights in potential nesting grounds to encourage nesting.Finally,the establishment of soft barriers around the nesting areas could increase the safety of nests.展开更多
针对中文汽车领域实体抽取任务中对嵌套实体、长实体识别效果差的问题,提出一种实体类别增强的嵌套实体抽取(ECE-NER)模型。首先,基于特征融合编码,提高模型对领域实体边界的感知能力;然后,尾词识别模块利用多层感知机得到实体尾词集合...针对中文汽车领域实体抽取任务中对嵌套实体、长实体识别效果差的问题,提出一种实体类别增强的嵌套实体抽取(ECE-NER)模型。首先,基于特征融合编码,提高模型对领域实体边界的感知能力;然后,尾词识别模块利用多层感知机得到实体尾词集合;最后,前向边界识别模块基于义原构造的实体类别特征和自注意力机制得到实体类别增强的候选尾词表征,融合领域实体类别特征,利用双仿射编码器计算特定尾词和实体类型的实体跨度概率,从而确定命名实体。在某汽车企业生产线故障数据集、汽车工业故障抽取评测数据集CCL2022和中文医学文本数据集CHIP2020上进行模型验证。实验结果表明,所提模型在前两个数据集上的实体识别F1值比序列标注模型(BERT+BiLSTM+CRF)、基于跨度的实体抽取模型(PURE(Princeton University Relation Extraction)、SpERT(Span-based Entity and Relation Transformer))分别提高了4.1、1.8、1.6个百分点和9.0、5.4、7.3个百分点;在第一个数据集和第三个数据集中嵌套实体识别F1值与PURE、SpERT模型相比提高了13.3、8.3个百分点和21.7、9.3个百分点,验证了所提模型在嵌套实体识别上的有效性。展开更多
The efficacy of nest-site choice ultimately determines the breeding success of birds. Comparisons of the reproductive strategies of various bird species which inhabit the same habitat may provide insights on the evolu...The efficacy of nest-site choice ultimately determines the breeding success of birds. Comparisons of the reproductive strategies of various bird species which inhabit the same habitat may provide insights on the evolution of the diverse life-history strategies in birds. In this study, nest-site choice and breeding success of four species of passerine birds that rely on reeds for reproduction were investigated in a wetland in Hebei, China. The four species were the Oriental reed warbler(Acrocephalus orientalis)(ORW), the blunt-winged warbler(Acrocephalus concinens)(BW), the reed parrotbill(Paradoxornis heudei)(RP), and the vinous-throated parrotbill(Sinosuthora webbiana)(VP). Our results showed that breeding nests of the four species were distributed in a mosaic pattern within the same habitat, with similar nest shapes/structures and nest-sites in the reeds. The only characteristics which differed significantly among the species were nest height above the water surface, height of reeds where nests were placed, and density of reeds around the nest site. In addition, the starting time of reproduction clearly differed for the four species. The breeding success rates of the four species were 34.5%(86/249) for ORW, 35.3%(6/17) for BW, 38.5%(15/39) for RP, and 40.9%(9/22) for VP in the two study years. The main factors affecting the breeding success were nest predation and poor weather conditions, like heavy rainstorms and wind, while nest parasitism by the common cuckoo(Cuculus canorus) represented an important factor for breeding failure only in the Oriental reed warbler. Our study demonstrated that these four sympatric species of passerine birds inhabiting the same wetland exhibit differences in terms of nest-site choice and breeding phenology.展开更多
The quality of a breeding site may have major fitness consequences.A fundamental step to understanding the process of nest-site selection is the identification of the information individuals use to choose high-quality...The quality of a breeding site may have major fitness consequences.A fundamental step to understanding the process of nest-site selection is the identification of the information individuals use to choose high-quality nest sites.For secondary cavity-nesting bird species that do not add nest lining material,organic remains (faeces,pellets)accumulated inside nest cavities during previous breeding events may be a cue for high-quality nest-sites,as they contain information about past successful breeding and may improve thermal insulation of eggs during incubation.However,cavities in which breeding was successful might also contain more nest-dwelling ectoparasites than unoccupied cavities, offering an incentive for prospective parents to avoid them.We exposed breeding cavity-nesting lesser kestrels (Falco naumanni)to nestbox dyads consisting of a dirty (with a thick layer of organic substrate) and a clean nestbox (without organic material).Dirty nestboxes were strongly preferred,being occupied earlier and more frequently than clean ones.Hatching success in dirty nestboxes was significantly higher than in clean ones,suggesting a positive effect of organic nest material on incubation efficiency, while nestbox dirtiness did not significantly affect clutch and brood size.Nestlings from dirty nestboxes had significantly higher ectoparasite load than those from clean nestboxes soon after egg hatching,but this difference was not evident a few days later.Nest substrate did not significantly affect nestling growth.We concluded that nest substrate is a key driver of nest-site choice in lesser kestrels,although the adaptive value of such a strong preference appears elusive and may be context-dependent.展开更多
基金supported by the National Natural Science Foundation of China(No.31272330)the Scientific Research Innovation Team Projects of Leshan Normal University
文摘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.
文摘The Great Spotted Woodpecker Dendrocopos major （L.）, one of the natural predators of Anoplophora glabripennis （Motsch.） （Coleoptera： Cerambycidae）, is resident to Wulate Qianqi County of the Inner Mongolia and widely found in shelter plantations. In August 2005 and 2006, 174 and 153 nest-cavities of Great Spotted Woodpeckers were found respectively in Wulate Qianqi County and 22 breeding nest-cavities were investigated in 2007. The results showed that mostly willow species were selected for nesting by the Great Spotted Woodpecker, but mature poplar trees also could be chosen. Nest cavities were often found with a protuberance above the cavity entrance or with a downward sloping gradient, or both. The selection of the height of the nest-cavity height was not significant. The vertical diameter of the nest-cavity entrance （VDE） and the horizontal diameter of the nest-cavity entrance （HDE） ranged from 5.0 to 5.8 cm. The results also indicated that the compass orientation of more than 60% of nest-cavities were towards the north, northeast and east. This study suggests a convergence of some nest-cavity characteristics of the Great Spotted Woodpecker in shelter plantations and will help us to make artificial nest for conserving the woodpecker and, as well, use the bird for controlling pests.
基金funded by the National Natural Science Foundation of China(Nos.31472013 and 31772453 to WL)
文摘Background:Information pertaining to nest-site fidelity and breeding dispersal over successive years can help to better our understanding of how birds respond to nest predation.Methods:By using mist nets and tracking the color banded individuals,we investigated nest-site fidelity and breeding dispersal by Common Tailorbirds(Orthotomus sutorius)throughout a year and between successive years in 2017–2018.Results:The present study showed that Common Tailorbirds could produce up to four clutches per breeding season.When multiple broods were produced within a year,breeding pairs remained together,and the nest rebuilding rate was up to 92.2%,with only four cases(7.8%)in which birds reused their old nests.The dispersal distance between the nests during multiple breeding was found to be 10.0±10.5 m,and nest-site fidelity within the same year was 90.0%.By the second year of breeding,76.2%of individuals remained in the original breeding pairs,while for those that did switch partners,the females remained in the nest from the previous year and paired with new males.The dispersal distance between years was 26.5±41.9 m,and nest-site fidelity between different years was 80.1%.There was no significant difference between within-year and between-year dispersal distances.Moreover,there was no significant difference in the dispersal distance of rebuilt nests between birds that had experienced nest predation and those that had not.Conclusions:Our findings suggest that Common Tailorbirds maintain a high degree of fidelity to mates and nestsites,and nest predation had no significant effect on territorial changes or breeding dispersal distance between each breeding attempt.
基金supported by the National Natural Science Foundation of China(Grant No.32171530 and 31472020)。
文摘Nest site selection is a vital component of bird reproduction success,and an adaptive behavior conducted to decrease nest predation risk with avoiding external disturbances.Understanding patterns of nest site selection can provide insights into how species adapt to changes in their habitat and has important conservation implications.In this study,we used microhabitat variables and multi-scale data with a field survey of nest occurrence to determine nest site selection patterns and adaptive strategies of the breeding Oriental Storks(Ciconia boyciana)in different nest areas.Results demonstrate that the nest site microhabitat characteristics of the breeding Oriental Storks significantly differed among the three nesting areas,and nest height was higher in the middle and lower Yangtze River floodplain than in the Northeast China and Bohai Bay nest areas.The food resources and intensity of human disturbance had the greatest effects on the nest site selection of the breeding Oriental Storks.The intensity of human disturbance was positively correlated with the nest height of the breeding Oriental Storks in Bohai Bay and the middle and lower Yangtze River floodplain;however,nest height decreased with the abundance of food resources in the Northeast China nest area.Our findings indicate that the nest site selection patterns of Oriental Storks showed flexible adaptive strategies.In safer environments,nests were lower and closer to food resources,which allows parent storks to invest more in the nestlings.However,in areas where human activity was intense,nests were higher to ensure the safety of their offspring.Some measures that could be taken to improve the breeding habitat of Oriental Storks include increasing the percentage of wetland areas in nesting areas to enhance food resources availability and setting artificial nests at suitable heights in potential nesting grounds to encourage nesting.Finally,the establishment of soft barriers around the nesting areas could increase the safety of nests.
文摘针对中文汽车领域实体抽取任务中对嵌套实体、长实体识别效果差的问题,提出一种实体类别增强的嵌套实体抽取(ECE-NER)模型。首先,基于特征融合编码,提高模型对领域实体边界的感知能力;然后,尾词识别模块利用多层感知机得到实体尾词集合;最后,前向边界识别模块基于义原构造的实体类别特征和自注意力机制得到实体类别增强的候选尾词表征,融合领域实体类别特征,利用双仿射编码器计算特定尾词和实体类型的实体跨度概率,从而确定命名实体。在某汽车企业生产线故障数据集、汽车工业故障抽取评测数据集CCL2022和中文医学文本数据集CHIP2020上进行模型验证。实验结果表明,所提模型在前两个数据集上的实体识别F1值比序列标注模型(BERT+BiLSTM+CRF)、基于跨度的实体抽取模型(PURE(Princeton University Relation Extraction)、SpERT(Span-based Entity and Relation Transformer))分别提高了4.1、1.8、1.6个百分点和9.0、5.4、7.3个百分点;在第一个数据集和第三个数据集中嵌套实体识别F1值与PURE、SpERT模型相比提高了13.3、8.3个百分点和21.7、9.3个百分点,验证了所提模型在嵌套实体识别上的有效性。
基金The National Natural Science Foundation of China (31672303, 31472013, 31772453)The Science and Technology Research and Development Project of Chengde (202002A088)。
文摘The efficacy of nest-site choice ultimately determines the breeding success of birds. Comparisons of the reproductive strategies of various bird species which inhabit the same habitat may provide insights on the evolution of the diverse life-history strategies in birds. In this study, nest-site choice and breeding success of four species of passerine birds that rely on reeds for reproduction were investigated in a wetland in Hebei, China. The four species were the Oriental reed warbler(Acrocephalus orientalis)(ORW), the blunt-winged warbler(Acrocephalus concinens)(BW), the reed parrotbill(Paradoxornis heudei)(RP), and the vinous-throated parrotbill(Sinosuthora webbiana)(VP). Our results showed that breeding nests of the four species were distributed in a mosaic pattern within the same habitat, with similar nest shapes/structures and nest-sites in the reeds. The only characteristics which differed significantly among the species were nest height above the water surface, height of reeds where nests were placed, and density of reeds around the nest site. In addition, the starting time of reproduction clearly differed for the four species. The breeding success rates of the four species were 34.5%(86/249) for ORW, 35.3%(6/17) for BW, 38.5%(15/39) for RP, and 40.9%(9/22) for VP in the two study years. The main factors affecting the breeding success were nest predation and poor weather conditions, like heavy rainstorms and wind, while nest parasitism by the common cuckoo(Cuculus canorus) represented an important factor for breeding failure only in the Oriental reed warbler. Our study demonstrated that these four sympatric species of passerine birds inhabiting the same wetland exhibit differences in terms of nest-site choice and breeding phenology.
文摘The quality of a breeding site may have major fitness consequences.A fundamental step to understanding the process of nest-site selection is the identification of the information individuals use to choose high-quality nest sites.For secondary cavity-nesting bird species that do not add nest lining material,organic remains (faeces,pellets)accumulated inside nest cavities during previous breeding events may be a cue for high-quality nest-sites,as they contain information about past successful breeding and may improve thermal insulation of eggs during incubation.However,cavities in which breeding was successful might also contain more nest-dwelling ectoparasites than unoccupied cavities, offering an incentive for prospective parents to avoid them.We exposed breeding cavity-nesting lesser kestrels (Falco naumanni)to nestbox dyads consisting of a dirty (with a thick layer of organic substrate) and a clean nestbox (without organic material).Dirty nestboxes were strongly preferred,being occupied earlier and more frequently than clean ones.Hatching success in dirty nestboxes was significantly higher than in clean ones,suggesting a positive effect of organic nest material on incubation efficiency, while nestbox dirtiness did not significantly affect clutch and brood size.Nestlings from dirty nestboxes had significantly higher ectoparasite load than those from clean nestboxes soon after egg hatching,but this difference was not evident a few days later.Nest substrate did not significantly affect nestling growth.We concluded that nest substrate is a key driver of nest-site choice in lesser kestrels,although the adaptive value of such a strong preference appears elusive and may be context-dependent.
