The Beijing Swift(Apus apus pekinensis)is a typical cavity-nesting bird that often nests inside holes and crevices in old architectures.Direct observation of their breeding behaviour is challenging and their breeding ...The Beijing Swift(Apus apus pekinensis)is a typical cavity-nesting bird that often nests inside holes and crevices in old architectures.Direct observation of their breeding behaviour is challenging and their breeding ecology is thus poorly studied.In this study,we analysed light-level geolocation data collected from six Beijing Swifts for the first time.Our results showed that geolocators can make comprehensive inference of their incubation period and behaviour.As a cost-effective and non-invasive method,geolocators can not only facilitate discovering migration routes,but also can be widely applied in the study of avian reproductive behaviour,especially in cavity-nesting bird species.We further discussed the characteristics and merits of this method and compared with other conventional nest-monitoring methods in recording birds.展开更多
Pallid Swifts(Apus pallidus),as other swifts,are birds extremely adapted to an aerial lifestyle,showing unique adaptations that allow them to fly almost continuously.The diet of these non-stopping high-altitudinal aer...Pallid Swifts(Apus pallidus),as other swifts,are birds extremely adapted to an aerial lifestyle,showing unique adaptations that allow them to fly almost continuously.The diet of these non-stopping high-altitudinal aerial birds has been mostly studied through techniques that fail to produce highly resolved prey identifications,and for that have been replaced by molecular techniques,such as DNA metabarcoding.Faecal samples of Pallid Swifts were monthly collected from a colony in the north of Portugal during the breeding season.DNA from the faecal samples was used to sex the birds and to identify the arthropods present in the diet through DNA metabarcoding.From the detected prey items,74 families were identified belonging to 16 orders,with Hymenoptera and Hemiptera being the most frequently consumed.There were seasonal variations in diet richness,composition and prey size.Regarding the diet of males and females,although no differences were found between the diet of males and females in terms of composition and richness,there were differences in the size of arthropods preyed by the different sexes,with males feeding on larger arthropods.The large seasonal variation in Pallid Swifts’diet during the breeding season is probably a result of spatiotemporal variation in aerial prey,of which swifts likely predate opportunistically.Although no significant differences were detected in diet richness and composition between sexes,the fact that males consumed larger prey may suggest the existence of sexual dietary segregation in this group of birds.At last,several pest species were found in these swifts’diet,which,if studied through DNA metabarcoding,can be used to monitor small arthropods,including airborne pests.展开更多
主发起动试验时,由于辅助动力装置(auxillary power units,APU)输出轴功率在主发指令发出时刻无法与电力加载功率同步响应而出现超转现象,设计了一种以可编程逻辑控制器(programmable logic controller,PLC)为控制器,西门子视窗控制中心...主发起动试验时,由于辅助动力装置(auxillary power units,APU)输出轴功率在主发指令发出时刻无法与电力加载功率同步响应而出现超转现象,设计了一种以可编程逻辑控制器(programmable logic controller,PLC)为控制器,西门子视窗控制中心(windows control center,WinCC)组态软件为上位机的主发联动试验系统。通过分析超转现象原因指出了主发起动系统存在不足,然后着重阐述了改进后的主发联动试验系统,主要采用主发指令与加载指令联动方式、预加载控制策略及调节加载完成与主发起动完成之间的时滞差,解决了主发起动试验过程中存在的超转问题。经过长时间试验运行表明:该系统及方法是一种解决APU超转现象的有效途径,且运行稳定可靠,具有推广应用价值。展开更多
基金funded by SHAN SHUI Conservation Centre,Beijing。
文摘The Beijing Swift(Apus apus pekinensis)is a typical cavity-nesting bird that often nests inside holes and crevices in old architectures.Direct observation of their breeding behaviour is challenging and their breeding ecology is thus poorly studied.In this study,we analysed light-level geolocation data collected from six Beijing Swifts for the first time.Our results showed that geolocators can make comprehensive inference of their incubation period and behaviour.As a cost-effective and non-invasive method,geolocators can not only facilitate discovering migration routes,but also can be widely applied in the study of avian reproductive behaviour,especially in cavity-nesting bird species.We further discussed the characteristics and merits of this method and compared with other conventional nest-monitoring methods in recording birds.
基金supported by the project TOPDEVILfinanced by Fundacão para a Ciencia e a Tecnologia(FCT)and the European Regional Development Fund(FEDER)through Portugal 2020 Competitiveness and Internationalization Operational Programme(POCI),reference POCI-01-0145-FEDER-030250 and PTDC/ASP-SIL/30250/2017funded by FCT through the research contracts 2020.02547.CEECIND and CEECIND/02064/2017,respectively。
文摘Pallid Swifts(Apus pallidus),as other swifts,are birds extremely adapted to an aerial lifestyle,showing unique adaptations that allow them to fly almost continuously.The diet of these non-stopping high-altitudinal aerial birds has been mostly studied through techniques that fail to produce highly resolved prey identifications,and for that have been replaced by molecular techniques,such as DNA metabarcoding.Faecal samples of Pallid Swifts were monthly collected from a colony in the north of Portugal during the breeding season.DNA from the faecal samples was used to sex the birds and to identify the arthropods present in the diet through DNA metabarcoding.From the detected prey items,74 families were identified belonging to 16 orders,with Hymenoptera and Hemiptera being the most frequently consumed.There were seasonal variations in diet richness,composition and prey size.Regarding the diet of males and females,although no differences were found between the diet of males and females in terms of composition and richness,there were differences in the size of arthropods preyed by the different sexes,with males feeding on larger arthropods.The large seasonal variation in Pallid Swifts’diet during the breeding season is probably a result of spatiotemporal variation in aerial prey,of which swifts likely predate opportunistically.Although no significant differences were detected in diet richness and composition between sexes,the fact that males consumed larger prey may suggest the existence of sexual dietary segregation in this group of birds.At last,several pest species were found in these swifts’diet,which,if studied through DNA metabarcoding,can be used to monitor small arthropods,including airborne pests.
文摘主发起动试验时,由于辅助动力装置(auxillary power units,APU)输出轴功率在主发指令发出时刻无法与电力加载功率同步响应而出现超转现象,设计了一种以可编程逻辑控制器(programmable logic controller,PLC)为控制器,西门子视窗控制中心(windows control center,WinCC)组态软件为上位机的主发联动试验系统。通过分析超转现象原因指出了主发起动系统存在不足,然后着重阐述了改进后的主发联动试验系统,主要采用主发指令与加载指令联动方式、预加载控制策略及调节加载完成与主发起动完成之间的时滞差,解决了主发起动试验过程中存在的超转问题。经过长时间试验运行表明:该系统及方法是一种解决APU超转现象的有效途径,且运行稳定可靠,具有推广应用价值。
