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Kentish Plover(Charadrius alexandrinus) and Little Tern(Sternula albifrons) prefer shells for nesting:A field experiment
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作者 Macarena Castro Andrés De la Cruz +1 位作者 Nuria Martin-Sanjuan Alejandro Pérez-Hurtado 《Avian Research》 SCIE CSCD 2024年第1期55-59,共5页
Shorebird populations are declining worldwide,mainly due to human disturbances and loss of coastal wetlands.However,supratidal habitats as saltpans could play a role in buffering human impact.Saltpans have shown to be... Shorebird populations are declining worldwide,mainly due to human disturbances and loss of coastal wetlands.However,supratidal habitats as saltpans could play a role in buffering human impact.Saltpans have shown to be important as feeding or breeding sites of some shorebird species.A potential conservation strategy to increase shorebird populations in saltpans is to manipulate the cues that birds use to select optimal breeding habitat.Here it is hypothesized that shorebirds are attracted to bivalve shells due to the advantages they offer.Following this hypothesis,we supplemented a restored saltpan in 2019 and 2021 with bivalve shells,expecting an increase in the number of breeding birds’ nests.More than 75% of Kentish Plover(Charadrius alexandrinus) and Little Tern(Sternula albifrons) nests were found in patches with shells in both years.The best model for both species indicates that the presence of shells is the factor that most correlates with the location of nests.The probability of choosing one place over another to settle their nest increases in areas with an abundance of shells,double in the case of the Kentish Plover and triple in the case of the Little Tern.The result of this study may constitute a valuable tool for attracting birds to restored saltpans and could contribute to the success of expensive restoration projects where time is usually a constraint. 展开更多
关键词 Habitat management Nest site selection Saltpan restoration Shell supplementation SHOREBIRDS
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Modelling the nesting-habitat of threatened vulture species in the caucasus:An ecosystem approach to formalising environmental factors in species distribution models
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作者 Rustam Pshegusov Victoria Chadaeva 《Avian Research》 SCIE CSCD 2023年第4期572-585,共14页
Abiotic factors play an important role in species localisation,but biotic and anthropogenic predictors must also be considered in distribution modelling for models to be biologically meaningful.In this study,we formal... Abiotic factors play an important role in species localisation,but biotic and anthropogenic predictors must also be considered in distribution modelling for models to be biologically meaningful.In this study,we formalised the biotic predictors of nesting sites for four threatened Caucasian vultures by including species distribution models(wild ungulates,nesting tree species)as biotic layers in the vulture Maxent models.Maxent was applied in the R dismo package and the best set of the model parameters were defined in the R ENMeval package.Performance metrics were continuous Boyce index,Akaike's information criterion,the area under receiver operating curve and true skill statistics.We also calculated and evaluated the null models.Kernel density estimation method was applied to assess the overlap of vulture ecological niches in the environmental space.The accessibility of anthropogenic food resources was estimated using the Path Distance measure that considers elevation gradient.The availability of pine forests(Scots Pine)and wild ungulates(Alpine Chamois and Caucasian Goat)contributed the most(29.6%and 34.3%)to Cinereous Vulture(Aegypius monachus)nesting site model.Wild ungulate distribution also contributed significantly(about 46%)to the Bearded Vulture(Gypaetus barbatus)model.This scavenger nests in the highlands of the Caucasus at a minimum distance of 5–10 km from anthropogenic facilities.In contrast,livestock as a food source was most important in colony distribution of Griffon Vulture(Gyps fulvus).The contribution of distances to settlements and agricultural facilities to the model was 45%.The optimal distance from Egyptian Vulture(Neophron percnopterus)nesting sites to settlements was only 3–10 km,to livestock facilities no more than 15 km with the factor contribution of about 57%.Excluding the wild ungulate availability,the ecological niches of studied vultures overlapped significantly.Despite similar foraging and nesting requirements,Caucasian vultures are not pronounced nesting and trophic competitors due to the abundance of nesting sites,anthropogenic food sources and successful niche sharing. 展开更多
关键词 Caucasian vultures Ecological niche differentiation Maxent nesting sites Species distribution models
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Nesting Biology and Site Selection of Olive Ridley—A Coherence of Nature
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作者 Arun Malarvizhi P. M. Mohan 《Open Journal of Marine Science》 2023年第2期29-39,共11页
Nesting behaviour of sea turtles remains a subject to study, due to their enigmatic pattern of seasonal breeding activities. In the present study, characteristics of the breeding turtle, Olive Ridley (Lepidochely... Nesting behaviour of sea turtles remains a subject to study, due to their enigmatic pattern of seasonal breeding activities. In the present study, characteristics of the breeding turtle, Olive Ridley (Lepidochelys olivacea) at Ramnagar along N-E coast of North Andaman Islands were investigated, for the nesting periods 2016-2017. Olive Ridley is the dominant sea turtles, with more than 300 individuals nesting every season with at least a 75% hatching success rate. It is one of the conducive, highly protective and undisturbed nesting sites for Olive Ridley on North Andaman coast. In the present study an initiative is made, to identify nature’s cues and the biological characteristics of Olive Ridley, which leads it to nest at Ramnagar beach, with a high hatchling success rate. 展开更多
关键词 Sea Turtle Olive Ridley Ramnagar Beach nesting Beach Sand Grain Hatch-ling North Andaman
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The Probable Cause for Nesting Pattern of Olive Ridley (Lepidochelys olivacea) at Ramnagar Beach, North East Coast of Andaman Island, India
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作者 Arun Malarvizhi M. M. Ilaamurughu P. M. Mohan 《Open Journal of Marine Science》 2023年第1期7-27,共21页
The nesting behaviour of sea turtles remains a subject to study, due to their enigmatic pattern of seasonal breeding activities. Over a period of time, several reports have been made in this context associated with th... The nesting behaviour of sea turtles remains a subject to study, due to their enigmatic pattern of seasonal breeding activities. Over a period of time, several reports have been made in this context associated with the nesting behaviour of the Olive Ridley turtles. In the present study, characteristics of the breeding beach and nesting pattern of Olive Ridley (Lepidochelys olivacea) at Ramnagar along N-E coast of Andaman Islands were investigated, during the nesting periods 2016-2017. The study area hosts Olive Ridley, the dominant sea turtles with more than 300 individuals nesting each year. For this study, the number of sea turtles visited, nested, the sediment characters, salinity, and temperature were taken. The exposed sandy nesting beach characteristics are prone to varying degrees of morphological changes every day. The results depict that even though similar grain size (Coarse Sand to Fine Sand and Very well sorted to Poorly Sorted), with an ambient incubating temperature, pH and salinity with wide nesting area, the selective nesting in the particular location of the beach identified because of comfortable energy conditions in the waters (1.5 m/s) favours the female turtles to reach the beach at the preferable site of Ramnagar and nest. 展开更多
关键词 Sea turtle Olive Ridley Ramnagar Beach nesting Environment Morphological Changes Sand Grain HATCHLING North Andaman
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The effects of climate and land use change on the potential distribution and nesting habitat of the Lesser Adjutant in Nepal
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作者 Hem Bahadur Katuwal Hari Prasad Sharma +10 位作者 Prashant Rokka Krishna Prasad Bhusal Bishnu Prasad Bhattarai Sabina Koirala Sandeep Chhetri Luitel Shailendra Yadav Ganesh Sah Hem Sagar Baral Laxman Prasad Poudyal Lin Wang Rui-Chang Quan 《Avian Research》 SCIE CSCD 2023年第3期326-335,共10页
Climate change and land use change pose a threat to the world’s biodiversity and have significant impacts on the geographic distribution and composition of many bird species,but little is known about how they affect ... Climate change and land use change pose a threat to the world’s biodiversity and have significant impacts on the geographic distribution and composition of many bird species,but little is known about how they affect threatened large-sized waterbird species that rely on agricultural landscapes.To address this gap,we investigated how climate and land use changes influence the distribution and nesting habitats of the globally vulnerable Lesser Adjutant(Leptoptilos javanicus) in Nepal.Between 2012 and 2023,we collected distribution data from 24 districts and nesting site information from 18 districts.In a nation-wide breeding survey conducted in 2020,we documented a total of 581 fledglings from 346 nests in 109 colonies.The ensemble model predicted a current potential distribution of 15%(21,637 km2) and a potential nesting habitat of 13%(19,651 km2) for the species in Nepal.The highest predicted current suitable distribution and nesting habitat was in Madhesh Province,while none was predicted in Karnali Province.The majority of this predicted distributional and nesting habitat falls on agricultural landscapes(>70%).Our model showed a likely range expansion of up to 15%(21,573 km2) for the distribution and up to 12%(17,482 km2) for the nesting habitat under SSP5-8.5 scenarios for the 2070s.The range expansion is expected to occur mainly within the current distribution and breeding range(Tarai and some regions of Siwalk),particularly in Lumbini and Sudurpashchim provinces,and extend to the northern portions(Siwalik and Mid-hill regions) in other provinces.However,the current Protected Areas and Important Bird and Biodiversity Areas are inadequate for providing optimal habitats for the species.Although the model suggests range expansion,the use of such novel habitats is primarily contingent on the availability and protection of large-sized trees(particularly Bombax ceiba,observed in 65% of colonies) in agricultural regions where nesting occurs.Therefore,our research suggests that agricultural landscapes should be prioritized in management plans for the conservation of the Lesser Adjutant in Nepal. 展开更多
关键词 Agricultural landscapes Bombax ceiba Ensemble modeling Farmland bird IBA Nest site
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一种基于NeSTiNg的TSN强实时流量调度和自动配置方法 被引量:2
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作者 王波 高文炜 +1 位作者 徐丹妮 贺新乐 《微电子学与计算机》 2022年第11期62-68,共7页
流量调度是时间敏感网络(Time Sensitive Networking, TSN)技术的核心.在大型工业嵌入式系统应用中,TSN流量调度的设计和仿真阶段需要对链路、流、门控等调度信息进行复杂且苛刻的配置.现有的基于仿真框架的配置方法多采用手动配置,这... 流量调度是时间敏感网络(Time Sensitive Networking, TSN)技术的核心.在大型工业嵌入式系统应用中,TSN流量调度的设计和仿真阶段需要对链路、流、门控等调度信息进行复杂且苛刻的配置.现有的基于仿真框架的配置方法多采用手动配置,这阻碍了这些框架对大型TSN网络的适用性.基于TSN强实时流量传输机制和NeSTiNg(Network Simulator for Time-Sensitive Networking)框架,提出一种适用于大型网络的强实时流量调度和自动配置方法.首先,该方法区别于传统的手动配置输入方式,实现了对流偏移、门状态和路由表等信息的自动配置;其次,该方法提取了流的端到端时延,验证了大型网络中TSN传输的强实时性;最后,通过计算拓扑变化后选择新路径的运算时间,评估了该方法对动态拓扑的适用性.结果表明:该方法保证了大型网络中大量流传输的强实时性,且当拓扑改变时,相比于静态路由有更低的运算时间. 展开更多
关键词 TSN IEEE 802.1Qbv nesting 流量调度 自动配置 TSN评估 运算时间
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Algorithm for 2D irregular-shaped nesting problem based on the NFP algorithm and lowest-gravity-center principle 被引量:5
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作者 LIU Hu-yao HE Yuan-jun 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2006年第4期570-576,共7页
The nesting problem involves arranging pieces on a plate to maximize use of material. A new scheme for 2D ir- regular-shaped nesting problem is proposed. The new scheme is based on the NFP (No Fit Polygon) algorithm a... The nesting problem involves arranging pieces on a plate to maximize use of material. A new scheme for 2D ir- regular-shaped nesting problem is proposed. The new scheme is based on the NFP (No Fit Polygon) algorithm and a new placement principle for pieces. The novel placement principle is to place a piece to the position with lowest gravity center based on NFP. In addition, genetic algorithm (GA) is adopted to find an efficient nesting sequence. The proposed scheme can deal with pieces with arbitrary rotation and containing region with holes, and achieves competitive results in experiment on benchmark datasets. 展开更多
关键词 nesting Cutting stock No Fit Polygon (NFP) Genetic algorithm (GA) Lowest gravity center
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眼针对脑缺血再灌注损伤大鼠Nesting、GAP43蛋白表达影响 被引量:4
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作者 宓丹 潘冲 陈雪 《辽宁中医药大学学报》 CAS 2018年第10期119-122,共4页
目的:通过观察眼针治疗对脑缺血再灌注损伤大鼠大脑皮层巢蛋白(Nesting)、生长相关蛋白43(Growth associated protein 43,GAP43)蛋白表达的影响,探讨眼针治疗对脑缺血后神经再生作用。方法:SD大鼠随机分为空白组、假手术组、模型... 目的:通过观察眼针治疗对脑缺血再灌注损伤大鼠大脑皮层巢蛋白(Nesting)、生长相关蛋白43(Growth associated protein 43,GAP43)蛋白表达的影响,探讨眼针治疗对脑缺血后神经再生作用。方法:SD大鼠随机分为空白组、假手术组、模型组(3 h、24 h、72 h)、眼针组(3 h、24 h、72 h),每组6只。采用改良线栓法制备大脑中动脉缺血2 h再灌注损伤模型,眼针组给予眼针治疗方法,每12 h 1次,每次20 min。各组大鼠在治疗点结束后,对大鼠神经功能缺损进行评分,用Westblot法检测缺血侧大脑皮层Nesting、GAP43蛋白含量。结果:(1)眼针组24 h、72 h神经功能评分低于同时间点的模型组(P〈0.05)。(2)脑缺血后模型组Nesting蛋白表达升高并随着缺血时间延长持续升高,与空白组比较,P〈0.05;眼针组Nesting蛋白表达趋势与模型组相似,与模型组同时间点比较,眼针组Nesting蛋白表达升高更明显(P〈0.05)。(3)脑缺血后模型组GAP43蛋白表达升高并随着缺血时间延长持续升高,与空白组比差异明显(P〈0.05);眼针组GAP43蛋白表达趋势与模型组相似,与模型组同时间点比较,眼针组GAP43蛋白表达升高更明显(P〈0.05)。结论:眼针治疗可以促进脑缺血后Nesting、GAP43蛋白的表达,从而具有促进脑缺血后神经发生的作用。 展开更多
关键词 脑缺血 眼针 神经发生 nesting GAP43
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HABITAT SUITABILITY INDEX MODELS: GREY HERON NESTING IN ZHALONG NATIONAL NATURE RESERVE 被引量:1
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作者 孙洪志 高中信 王丹 《Journal of Northeast Forestry University》 SCIE CAS CSCD 1995年第2期61-64,共4页
Grey heron (Ardea cimerca) is one kind of the great birds which are often seen in the northeast marsh area of P.R.China, and there are many grey herons to reproduce in Zhalong Nature Reserve from March to August annua... Grey heron (Ardea cimerca) is one kind of the great birds which are often seen in the northeast marsh area of P.R.China, and there are many grey herons to reproduce in Zhalong Nature Reserve from March to August annually. In this paper, through the inveingation of the grey herons nesting habitat and according to the water depth, vegetation type, cover density and plan heigh of the nesting place, the grey heron’s nesting habitat suitability index medes are established. The main model is s=(s1xs2xs3xs4)1/4,where s1 is the water depth suitability index, s2 is the vegetation type suitability index, s3 is the cover density index, sa is the plant height suitability index. These models provide a kind of reliable method for evaluating the habitat quality of the grey heron’s nesting. 展开更多
关键词 GREY HERON nesting HABITAT INDEX MODEL
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Green Turtle, <i>Chelonia mydas</i>, Nesting and Temperature Profile of the Nesting Beach at Huyong Island, the Similan Islands in Andaman Sea 被引量:1
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作者 Sarawoot Gomuttapong Winai Klom-In +3 位作者 Jirarach Kitana Putsatee Pariyanonth Kumthorn Thirakhupt Noppadon Kitana 《Natural Resources》 2013年第4期357-361,共5页
Global change in temperature is regarded as a serious natural disaster that may cause extinction of organisms. Green turtle, Chelonia mydas, is not only an endangered species but also a species with temperature depend... Global change in temperature is regarded as a serious natural disaster that may cause extinction of organisms. Green turtle, Chelonia mydas, is not only an endangered species but also a species with temperature dependent sex determination that could be affected by the global warming. In this study, nesting and temperature profile of C. mydas nesting beach at HuyongIsland, the most important nesting site of C. mydas in Andaman Sea of Thailand, were studied in order to monitor a potential effect of regional climate change on the green turtle nesting activity and habitat. Nesting activities were surveyed during May-August 2011 and temperature profiles of the nesting beach were monitored for 58 days during the normal incubation period of this species. The total of 25 nests with clutch size of 105 ± 25 eggs was found during this study period suggesting normal nesting activity of the green turtle. Temperature profile of the nesting beach showed similar trend among nests with no clear influence of the vegetation cover. Mean nest temperature at the middle-third period, corresponding to the temperature-sensitive period of C. mydas, ranged from 28.3°C to 28.9°C, suggesting a slightly male-biased sex ratio of the offspring. Overall, temperature profile of the nesting beach showed little or no indication of adverse effects of regional increase in temperature on nesting activity and egg incubation of the green turtle at this period. 展开更多
关键词 Conservation nesting Ecology Sea TURTLE Thermal Profile
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Monitoring hawksbill turtle nesting sites in some protected areas from the Persian Gulf
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作者 Majid Askari Hesni Mohsen Rezaie-Atagholipour +7 位作者 Somaye Zangiabadi Mohammad Amin Tollab Mostafa Moazeni Hosein Jafari Mohammad Talebi Matin Ghasem Ghorbanzadeh Zafarani Mahtab Shojaei Abbas Motlaghnejad 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第12期43-51,共9页
Iranian nesting populations of the critically endangered hawksbill turtle(Eretmochelys imbricate) are some of the most important in the Indian Ocean. In this study, four of the most important hawksbill nesting grounds... Iranian nesting populations of the critically endangered hawksbill turtle(Eretmochelys imbricate) are some of the most important in the Indian Ocean. In this study, four of the most important hawksbill nesting grounds in the Persian Gulf, situated within three Iranian marine protected areas, were surveyed during nesting season,including Nakhiloo, Ommolgorm and Kharko Islands and the mainland beaches of the Naiband Marine-Coastal National Park(NMCNP). We present GIS maps of these key nesting grounds and describe sand texture of key nesting zones, along with conservation recommendations. About 9.2(28.3%) out of 32.5 km of all shores surveyed in this study were used by nesting hawksbill turtles follows: Nakhiloo: 1.4 km(52% of potential nesting area);Ommolgorm: 1.94 km(40%);Kharko: 3.4 km(28%), and NMCNP: 2.46 km(18.9%). The average nesting density was calculated as 131 nests/km at Nakhiloo, 76 nests/km at Ommolgorm, 7 nests/km at Kharko, and 15 nests per km at NMCNP. Highest nesting density was observed in Nakhiloo and Ommolgorm. It is thought that high hawksbill nesting density in these islands seems likely a result of limiting adequate nesting shores rather than the size of population, and also low density in Kharko and NMCNP more related to past and current pressures and low population density. With the exception of Ommolgorm Island, sands at the nesting grounds were well sorted.Grain size indicated that female hawksbill turtles in the Iranian Persian Gulf nest in sands that are generally mixed, with mean grain size ranging from coarse sands(0.4Φ;~0.5–1 mm) to fine sands(2Φ;~0.25 mm). We provide and discuss conservation recommendations and suggestions for future. 展开更多
关键词 marine protected areas marine turtles nesting sand texture GIS maps
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Genetic Algorithms to the Nesting Problem in the Leather Manufacturing Industry
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作者 张玉萍 蒋寿伟 尹忠慰 《Journal of Donghua University(English Edition)》 EI CAS 2005年第1期90-96,共7页
The nesting problem in the leather manufacturing is the problem of placing a set of irregularly shaped pieces (called stencils) on a set of irregularly shaped surfaces (called leathers sheets). This paper presents a n... The nesting problem in the leather manufacturing is the problem of placing a set of irregularly shaped pieces (called stencils) on a set of irregularly shaped surfaces (called leathers sheets). This paper presents a novel and promising processing approach. After the profile of leather sheets and stencils is obtained with digitizer, the discretization makes the processing independent of the specific geometrical information. The constraints of profile are regarded thoroughly. A heuristic bottom-left placement strategy is employed to sequentially locate stencils on sheets. The optimal placement sequence and rotation are deterimined by genetic algorithms (GA). A natural concise encoding method is developed to satisfy all the possible requirements of the leather nesting problem. The experimental results show that the proposed algorithm can not only be applied to the normal two-dimensional nesting problem, but also especially suitable for the placement of multiple two-dimensional irregular stencils on multiple two-dimensional irregular sheets. 展开更多
关键词 leather nesting genetic algorithms two-dimensional geometry IRREGULAR discretization.
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Is nesting in closed nestboxes advantageous for the European Robin(Erithacus rubecula)?
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作者 Rimvydas Juškaitis 《Avian Research》 CSCD 2021年第2期208-217,共10页
Background:The European Robin(Erithacus rubecula)is eurytopic in its choice of nest site,which can be either half-open or closed,and situated either on the ground or at a height of several meters.On occasion,robins al... Background:The European Robin(Erithacus rubecula)is eurytopic in its choice of nest site,which can be either half-open or closed,and situated either on the ground or at a height of several meters.On occasion,robins also nest in closed nestboxes,though generally only solitary such cases are documented,albeit that dozens of such events can be recorded during the course of some long-term studies.However,until now,nobody has summarised the peculiarities of robins nesting in closed nestboxes.Methods:In the period 1978-2020,wooden tit and starling nestboxes were inspected regularly at five study sites in Lithuania,this totaling more than 18,000 nestbox-seasons.During these inspections,90 cases of robins nesting in the nestboxes were recorded.Publications on this topic from the entire robin distribution range were reviewed.Results:Robins prefer to nest in old large-sized fairly shallow nestboxes with wide entrance holes,for example starling nestboxes or tit nestboxes with enlarged entrance holes.Increased numbers of nestboxes being occupied by robins were recorded for 3-8 years in row.In Lithuania,nesting success in nestboxes is not higher than compared with nesting on the ground.Tree climbing mammals,Pine Martens(Martes martes),Hazel Dormice(Muscardinus avellanarius),Edible Dormice(Glis glis)and Forest Dormice(Dryomys nitedula),are the main predators of robin nests in nestboxes.Conclusions:Some geographic variation was found in the occurrence of robins nesting in nestboxes with more such cases recorded in central and southern parts of the range.Possibly robins are more philopatric in these parts of the range,with the same females or their offspring nesting in nestboxes for several years in row.In areas inhabited by dormice,nesting in closed nestboxes is not advantageous for robins. 展开更多
关键词 Erithacus rubecula European Robin Nestbox dimensions nesting success Predators
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A high incidence of non-cavity nesting in an introduced population of House Sparrows suggests that the species should not be constrained by cavity-nest site availability
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作者 Elizabeth Louise Sheldon Simon Charles Griffith 《Avian Research》 CSCD 2017年第4期202-209,共8页
Background: The House Sparrow(Passer domesticus) has undergone dramatic population declines in many parts of Europe.It has been widely hypothesised that a lack of cavity nest sites has contributed to this decline.Howe... Background: The House Sparrow(Passer domesticus) has undergone dramatic population declines in many parts of Europe.It has been widely hypothesised that a lack of cavity nest sites has contributed to this decline.However the idea of the House Sparrow being nest site limited is somewhat incompatible with the long history of nest site plasticity in the species.Methods: The nest-site selection in a population of non-native House Sparrows introduced to Australia from Europe just over 150 years ago was characterised.The prevalence of non-cavity nesting was quantified,and nest-site selection in terms of landscape and nesting structure were described.Results: Flexible nesting behaviors were reported over a range of different landscapes and a surprisingly high rate of nesting in vegetation(43%) was documented.Most nests found in vegetation were not in cavities,but were woven into the foliage and supported by branches and stems.Conclusion: The high rate of vegetation nesting indicates that in this introduced population,the House Sparrow is unlikely to be constrained by cavity-nest site availability.The high degree of nest site plasticity in the Australian population may suggest that European House Sparrows have the potential to shift away from their proclivity for cavity nests.Future work in Europe should examine the incidence of non-cavity nesting in House Sparrows more closely,and perhaps reconsider the idea that House Sparrows are nest-site constrained. 展开更多
关键词 Passer domesticus Cavity nests House Sparrow decline nesting plasticity
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Breeding Status, Nesting Densities & Diet Trends of Two Endangered California Least Tern Colonies
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作者 David L. Riensche Meredith L. Elliott Susan H. Euing 《Journal of Environmental Science and Engineering(B)》 2012年第10期1135-1145,共11页
The California least tern (Sternula antillarum browni) is an endangered species. The two largest colonies of this bird species in the San Francisco Bay, California, USA, are located 23 km apart at Alameda Point and ... The California least tern (Sternula antillarum browni) is an endangered species. The two largest colonies of this bird species in the San Francisco Bay, California, USA, are located 23 km apart at Alameda Point and Hayward Regional Shoreline. The Alameda Point colony, on the former Naval Air Station, Alameda, has grown at an average rate of 9.2% per year since its discovery in 1976 and has a nesting density ranging from 1-153 nests per ha. Long-term breeding success at Alameda has averaged 0.86 fledglings per breeding pair. Least tems began appearing in 2003, at an island in Hayward enhanced with substrate mediums and social attraction devices. Successful breeding attempts have been observed at the Hayward colony since 2006. The Hayward colony has grown at an average rate of 51.5% per year, has a nesting density ranging from 33-333 nests per ha and long-term breeding success average of 0.87 fledglings per breeding pair. Dropped fish have been collected from both colonies, and silversides (family Atherinopsidae) are the dominant prey. Alameda terns forage on a greater variety of species than the Hayward terns. The regression results indicate the importance of Northern anchovy (Engraulis mordax) to the breeding success of the Alameda colony. 展开更多
关键词 California least tern endangered species breeding status nesting densities diet trends.
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Sea Turtle Nesting: What Is Known and What Are the Challenges under a Changing Climate Scenario
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作者 Raquel A. M. São Miguel Rita Anastácio Mário J. Pereira 《Open Journal of Ecology》 2022年第1期1-35,共35页
The rate of climate change experienced globally in recent decades may compromise sea turtles’ survival;especially temperature increase, which is particularly fast, impacts life history characteristics, such as temper... The rate of climate change experienced globally in recent decades may compromise sea turtles’ survival;especially temperature increase, which is particularly fast, impacts life history characteristics, such as temperature-dependent sex determination (TSD), late maturity and sea turtles highly migratory nature. This review aims to identify and summarize the information that has been collected from 2009-2020 in order to aid future empirical studies that seek to fill these and other knowledge gaps, and subsequently assist conservationists in making multilevel decisions to protect sea turtle populations and species. In a summarized way the general knowledge acquired so far on the influence of environmental abiotic and biotic factors on nesting behaviour and hatching, emergence and survival successes of sea turtle hatchlings, was gathered. To accomplish this work, a search on Web of Science, Science Direct, NCBI/PubMed, and Google Scholar was carried out using the terms “sea turtles + climate change”. Published articles in the period 2009-2020 were selected, related to the nesting ecology of 5 species of sea turtles: <em>Caretta caretta</em>, <em>Eretmochelys imbricata</em>, <em>Dermochelys coriacea</em>,<em> Chelonia mydas</em>, <em>Lepidochelys olivacea</em>. Emphasis was also placed on geographical information and on population location (e.g. climatic conditions during the nesting season). These articles (N = 126) were analysed giving relevance to researcher’s data interpretations, comparisons with other researches, and the reached conclusions. An attempt was made to represent all 5 species of sea turtles when selecting articles on each of the environmental factors that influence sea turtle nesting: temperature, humidity, nesting substrate, gases, depth of the nest, sea surface temperature (SST), nest location on the beach, nesting phenology and geographic distribution of nesting habitats. The interaction between these parameters and their consequences on the terrestrial phase of reproduction are presented and discussed. 展开更多
关键词 Reproductive Ecology Sea Turtles Climate Change nesting Phenology and Geographic Distribution of nesting Habitats
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Diversity, Habitat Utilization and Nesting Characteristics of Waterbirds in and around Maduru Oya Reservoir in Maduru Oya National Park, Sri Lanka
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作者 Kulathungage Hiranthi Dilrangi Wathmini De Silva Dharshani Mahaulpatha 《Open Journal of Ecology》 2021年第10期664-689,共26页
Maduru Oya National Park (MONP) including its largest reservoir, Maduru Oya Reservoir (MOR), has been identified with a high waterbird density. However, a limited number of researches have been conducted on waterbirds... Maduru Oya National Park (MONP) including its largest reservoir, Maduru Oya Reservoir (MOR), has been identified with a high waterbird density. However, a limited number of researches have been conducted on waterbirds in MONP. In this study, diversity, habitat use of waterbirds at MOR and their nesting characteristics were analyzed. Bird survey was carried out using the point count method and block count method. A common ethogram was constructed to identify the behavior categories. Percentage cover of habitat types was estimated by quadrat method. A total of 30 species belonging to 15 families were recorded, including two globally threatened species and three winter visitors. Year around Shannon-Weiner index for MOR was 1.491. Little Cormorant had the highest relative abundance. Percentage coverage of grass had increased gradually from March to September with the highest in September (69.27%) while open water had the highest coverage in the other months. Significantly high number of individuals used areas of grass, open water and mud for feeding and exposed rocks, dead trees/logs for resting (One-way ANOVA, p ≤ 0.05). Four waterbird species were observed building nests. Occupied nesting tree species were <em>Senna spectabilis</em> (Kaha Kona), <em>Dymorphocalyx glabellus</em> (Weliwanna) and <em>Alstonia scholaris </em>(RukAththana). The number of nests observed in three layers of canopy was significantly different (p ≤ 0.05). The highest average number of nests was observed in middle layer (8.90 ± 2.67). Black-headed Ibises had high preference to nest in <em>Dymorphocalyx glabellus</em> (p ≤ 0.05, 3.30 ± 1.32) while Great Cormorants (p ≤ 0.05, 2.38 ± 0.74) and Grey Herons (p ≤ 0.05, 4.27 ± 2.12) in <em>Alstonia scholaris</em>. Little Cormorants had no significant difference in their preference for nesting trees. As a preliminary study, this can be used for future research on waterbirds and to compose management and conservation plans. 展开更多
关键词 Aquatic Avifauna CONSERVATION WETLANDS nesting Ecology
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Nesting Activity and Conservation Status of the Hawksbill Turtle (Eretmochelys imbricata) in Persian Gulf
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作者 Seyyed Mohammad Bagher Nabavi Ruhollah Zare Mahdieh Eftekhar Vaghefi 《Journal of Life Sciences》 2012年第1期74-79,共6页
Nesting activity, declining factors and conversation strategy of hawksbill turtle (Eretmochelys imbricata) in Persian Gulf islands investigated. Nesting analysis and hatchability has been monitored by counting. Our ... Nesting activity, declining factors and conversation strategy of hawksbill turtle (Eretmochelys imbricata) in Persian Gulf islands investigated. Nesting analysis and hatchability has been monitored by counting. Our management strategy has been useful significantly in preserving hawksbill turtle existence. Depletion prevented, nesting habitats protected and better conservative programs designed. 展开更多
关键词 Hawksbill turtle (Eretmochelys imbricata) Persian Gulf nesting season conservation.
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Nesting and Berth Allocation by an Expert System Using Heuristic Search
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作者 Dongmok Sheen Yoonho Seo 《Journal of Software Engineering and Applications》 2017年第4期311-323,共13页
Nesting is a common problem in industries such as shipbuilding, auto-maker, clothing, shoe-making, and furniture, in which various parts are cut off from a stock or stocks while minimizing the wastes or maximizing the... Nesting is a common problem in industries such as shipbuilding, auto-maker, clothing, shoe-making, and furniture, in which various parts are cut off from a stock or stocks while minimizing the wastes or maximizing the utilization of the stock. Berth allocation at seaside is also considered one form of two dimensional nesting problems, in which a ship is assigned a location for service during a certain time slot. This paper presents an expert system using a heuristic search method for nesting problems. The parts and stocks are represented by pixels with which utility function is used to evaluate current state in search tree. The system is developed in CLIPS, an expert system shell and applied to various example problems with different constraints and to a berth allocation example to illustrate its applicability under different conditions. 展开更多
关键词 nesting BERTH ALLOCATION HEURISTIC Search CLIPS
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Nesting Orientalisms:Case of Hungary,Its Imaginary Occidentalisation Process,and Inconsistencies
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作者 Cemre Aydogan 《International Relations and Diplomacy》 2020年第1期22-28,共7页
What is the border between Central and Eastern Europe?This is an unanswered question in the literature of contemporary European history and politics.In the modern state system,imaginary boundaries are products of the ... What is the border between Central and Eastern Europe?This is an unanswered question in the literature of contemporary European history and politics.In the modern state system,imaginary boundaries are products of the imagined communities,and these boundaries also cause either to occidentalize or to orientalize the lands due to its top-down/elitist imagination procedure.During the Cold War years,anti-USSR voices are important to see the certain demand for Europeanization among people in today’s Central Europe where there especially had the communist legacy.In general,the ultimate goal is to identify themselves as more western among Central and Eastern European states for the sake of civilizational values of the Enlightenment and to reach today’s contested Neoliberal welfare.This desire causes Nesting Orientalisms,Milica Bakic-Hayden’s concept.Nesting Orientalisms are about re-constructing new Orient in the same region to hierarchizeitself as occidental.Through the process of mapping its location and construction of occidental identity,Hungary defines itself as a part of Central Europe.But what are the legitimated reasons of Hungary to define itself as Central European instead of Eastern Europe?Do these reasons perfectly fit in today’s Central European formulation and stereotype?What are the possible reasons to reject Hungary’s Central European self-definition?Moreover,under the shadow of the discussion on Central Europe vs.Eastern Europe,to what extent does the rise of authoritarianism block ongoing occidentalisation process of Hungary?In this research,I will answer these questions by analyzing modern political history of Hungary by the method of interpretivist process tracing. 展开更多
关键词 nesting Orientalisms Central Europe Eastern Europe Hungary Cold War occidentalisation
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