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
Changing landscapes and land-use practices are altering habitat for Florida wild turkeys (Meleagris gallopavo osceola). However, an understanding of habitat determinants of nest success is lacking for this unique turk...Changing landscapes and land-use practices are altering habitat for Florida wild turkeys (Meleagris gallopavo osceola). However, an understanding of habitat determinants of nest success is lacking for this unique turkey subspecies, potentially limiting conservation success. We examined female wild turkey nest site selection and nest success at microhabitat and patch levels using logistic regression in an Information-Theoretical framework in Florida, 2008-2010. We captured and radio-equipped adult female turkeys, and followed birds to nests. Nests were monitored to document success, and habitat was measured at multiple levels at nest and random sites. Females selected nest sites in dense vegetation (i.e., increased saw palmetto cover [Serenoa repens] and higher palm stem densities) that may have provided lateral and vertical cover for concealment at the microhabitat level (i.e., area within 7 m of the nest), while selecting for a more open habitat (i.e., decreasing hardwood and conifer stem densities) at the patch level (i.e., area within 28 m of the nest). Similarly, successful nests were in more dense vegetation at the nest site (i.e., increased saw palmetto cover) in an otherwise more open habitat (i.e., lower basal area) than unsuccessful nests. Habitat management that creates patches of dense shrub vegetation such as saw palmetto within an open landscape may be best for Florida wild turkey nesting habitat and success.展开更多
Background: Nest predation is usually the main cause of bird nest failure. ‘Predation avoidance hypothesis' of nestsite selection predicts that birds should prefer nest-sites with higher nesting success. We inves...Background: Nest predation is usually the main cause of bird nest failure. ‘Predation avoidance hypothesis' of nestsite selection predicts that birds should prefer nest-sites with higher nesting success. We investigated the relationship between nest height and nest fate in Silver-throated Tits(Aegithalos glaucogularis) and asked whether the seasonal change of nest height was adaptive by simultaneously analyzing the seasonal variation of predation rates of the nests.Methods: We monitored nests of the Silver-throated Tit across seven breeding seasons in the Dongzhai National Nature Reserve in Henan Province of China. We compared the difference of nesting success among nests of different heights and analyzed the effect of nesting date on nest height and nest predation rates.Results: The overall nesting success rate was 24.1%(n ds and mammals, followed by snakes(9.11%= 623). Among the failed nests(n). The average height of successf= 472), 59.75% were predated by birul nests was significantly lower than that of predated nests. As the season progresses, the height of the nests increased significantly, companied by the decrease in nesting success. Daily survival rate of the nests also decreased with the progression of the season, regardless of breeding stages.Conclusions: Our findings suggest that nest height is an important factor influencing the nesting success of Silverthroated Tits. However, the seasonal increase of nest height appears inconsistent to the ‘predation avoidance hypothesis', because it is associated with higher predation rates. The reason for this maladaptive behavior remains to be explored in future studies.展开更多
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
Background: Nest construction is a key element of avian reproductive behaviour and the result is often a complex structure that is used for incubation of eggs, which represents an extended phenotype. It is known that ...Background: Nest construction is a key element of avian reproductive behaviour and the result is often a complex structure that is used for incubation of eggs, which represents an extended phenotype. It is known that nest construction is a plastic behaviour but the extent to which plasticity is observed in a single species with a wide geographical distribution is largely unknown. This study sought to better understand variation in nest size and composition across a very wide geographical area. The hypothesis suggested that location would affect size but not composition of nests of the European Pied Flycatcher (Ficedula hypoleuca). Methods: Nests and reproductive data were collected from seventeen study sites, spread over 6° of latitude and 3.3° of longitude on the island of Great Britain. Dimensions of nests were measured before they were deconstructed to determine the masses and types materials used in the outer nest and the cup lining. Results: Geographical variation was observed in base thickness of nests but not many other dimensions. Nests varied in composition but were mainly made of leaf, moss, bark, grass, root and fern. Moss was used more to the north and east of the study area compared with more leaf mass towards the south and west. The species of leaf and bark used in the nests varied between geographical locations. Additionally, the use of leaves or bark from a particular tree species did not reflect the incidence of the tree species in the immediate territory. Conclusions: This study showed that nest composition was affected by geographical location over a wide area. Variation between nests at each location was high and so it was concluded that differences in nest composition reflect individual selection of materials but evidence is such that it remains unclear whether this is deliberate to fulfil a specific role in the nest, or simply opportunistic with birds simply picking up materials with the appropriate characteristics as they find them outside their nestbox.展开更多
Endemic to eastern Asia, the Japanese marsh warbler Megalurus pryeri is classified as “vulnerable” in the IUCN Red Data List. Very little information is available concerning the breeding biology of this species. Fro...Endemic to eastern Asia, the Japanese marsh warbler Megalurus pryeri is classified as “vulnerable” in the IUCN Red Data List. Very little information is available concerning the breeding biology of this species. From April to July 2004, we studied the breeding ecology of M.pryeri sinensis in Zhalong Nature Reserve, in northeastern China. The breeding season extended from late May until early August, with a peak in mid-June. Nest building and care of the young was undertaken primarily by females. Males defended their nesting territories, and drove away male intruders. The eggs of the Japanese marsh warbler are white, with tiny fawn spots (greatest diameter=16.88±0.86 mm,n=14); shortest diameter=12.76±0.51 mm,n=14). Clutch size averaged 5.4±1.2 (range 4-7 eggs, n=38 clutches). Incubation lasted for 10-13 days (Mean=11.9±0.8 days, n=18), with a hatching success of 59.9%. The nestling period (range 9-12 days, Mean 10.1±0.9 days, n=15) resulting in a fledgling success rate of 67.5%. Total breeding success was 41.4%. The main cause of nesting failure include human disturbance (cutting reeds), predation, and effects of grazing and flooding.展开更多
Background:The Maghreb Magpie(Pica mauritanica)is an endemic North African species.Available knowledge on this species is limited to historic descriptive data with no ecological information provided.Populations contin...Background:The Maghreb Magpie(Pica mauritanica)is an endemic North African species.Available knowledge on this species is limited to historic descriptive data with no ecological information provided.Populations continue to dramatically decline in Tunisia,where only one relic population survives.Investigating the breeding biology of this species is essential for conservation purposes.The purpose of this study was to increase our understanding of the Tunisian relic population and provide detailed data on breeding biology over two breeding seasons(2017 and 2018).Methods:This study occurred on a private farm of 650 ha,located 10 km from Dhorbania village at Kairouan Governorate,in central Tunisia.Active nests were monitored weekly during egg laying period and twice a week during hatching period.The Ivlev's electivity index was used to assess whether the frequency of use of nesting trees and bushes matched their availability in the study area.We recorded nest measurements and positions,and compared them using Wilcoxon signed-rank test.Variations of breeding parameters as number of eggs laid,hatchlings,and fledglings over years were performed using Mann–Whitney U-test andχ^(2) tests.We used a Generalized Linear Mixed Model(GLMM)to investigate how egg volume varied with clutch size and laying date.Results:We investigated clutch size,egg size,hatching and fledging success,and evaluated how these parameters varied according to laying date and nest characteristics.Clutch size averaged 5.00±0.19 but was significantly greater nest.Causes of nest failure included the depredation of nestlings by shrikes,cobras and rats(e.g.Lanius meridionalis,Naja haje and Rattus rattus),death of parents by the Black-shouldered Kite(Elanus caeruleus)and nest parasitism by the Great Spotted Cuckoo(Clamator glandarius).Clutch size,brood size and fledgling success were unaffected by laying date,nest volume and nest elevation.Egg volume decreased with laying date but was unaffected by clutch.Conclusion:Our study provides the first and only detailed data on reproductive parameters of the Maghreb Magpie in its entire geographic range(North Africa).Information gleaned from this study provides valuable information for monitoring and long-term conservation plans of the endangered Tunisian Magpie population.Additionally,our data provide an avenue of large-scale comparative studies of the reproductive ecology of the magpie complex.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Changing landscapes and land-use practices are altering habitat for Florida wild turkeys (Meleagris gallopavo osceola). However, an understanding of habitat determinants of nest success is lacking for this unique turkey subspecies, potentially limiting conservation success. We examined female wild turkey nest site selection and nest success at microhabitat and patch levels using logistic regression in an Information-Theoretical framework in Florida, 2008-2010. We captured and radio-equipped adult female turkeys, and followed birds to nests. Nests were monitored to document success, and habitat was measured at multiple levels at nest and random sites. Females selected nest sites in dense vegetation (i.e., increased saw palmetto cover [Serenoa repens] and higher palm stem densities) that may have provided lateral and vertical cover for concealment at the microhabitat level (i.e., area within 7 m of the nest), while selecting for a more open habitat (i.e., decreasing hardwood and conifer stem densities) at the patch level (i.e., area within 28 m of the nest). Similarly, successful nests were in more dense vegetation at the nest site (i.e., increased saw palmetto cover) in an otherwise more open habitat (i.e., lower basal area) than unsuccessful nests. Habitat management that creates patches of dense shrub vegetation such as saw palmetto within an open landscape may be best for Florida wild turkey nesting habitat and success.
基金supported by the Fundamental Research Funds for the Central Universities through Beijing Forestry University(No.2016JX06)the National Natural Science Foundation of China(Nos.3110144 and 31472011)
文摘Background: Nest predation is usually the main cause of bird nest failure. ‘Predation avoidance hypothesis' of nestsite selection predicts that birds should prefer nest-sites with higher nesting success. We investigated the relationship between nest height and nest fate in Silver-throated Tits(Aegithalos glaucogularis) and asked whether the seasonal change of nest height was adaptive by simultaneously analyzing the seasonal variation of predation rates of the nests.Methods: We monitored nests of the Silver-throated Tit across seven breeding seasons in the Dongzhai National Nature Reserve in Henan Province of China. We compared the difference of nesting success among nests of different heights and analyzed the effect of nesting date on nest height and nest predation rates.Results: The overall nesting success rate was 24.1%(n ds and mammals, followed by snakes(9.11%= 623). Among the failed nests(n). The average height of successf= 472), 59.75% were predated by birul nests was significantly lower than that of predated nests. As the season progresses, the height of the nests increased significantly, companied by the decrease in nesting success. Daily survival rate of the nests also decreased with the progression of the season, regardless of breeding stages.Conclusions: Our findings suggest that nest height is an important factor influencing the nesting success of Silverthroated Tits. However, the seasonal increase of nest height appears inconsistent to the ‘predation avoidance hypothesis', because it is associated with higher predation rates. The reason for this maladaptive behavior remains to be explored in future studies.
文摘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.
文摘Background: Nest construction is a key element of avian reproductive behaviour and the result is often a complex structure that is used for incubation of eggs, which represents an extended phenotype. It is known that nest construction is a plastic behaviour but the extent to which plasticity is observed in a single species with a wide geographical distribution is largely unknown. This study sought to better understand variation in nest size and composition across a very wide geographical area. The hypothesis suggested that location would affect size but not composition of nests of the European Pied Flycatcher (Ficedula hypoleuca). Methods: Nests and reproductive data were collected from seventeen study sites, spread over 6° of latitude and 3.3° of longitude on the island of Great Britain. Dimensions of nests were measured before they were deconstructed to determine the masses and types materials used in the outer nest and the cup lining. Results: Geographical variation was observed in base thickness of nests but not many other dimensions. Nests varied in composition but were mainly made of leaf, moss, bark, grass, root and fern. Moss was used more to the north and east of the study area compared with more leaf mass towards the south and west. The species of leaf and bark used in the nests varied between geographical locations. Additionally, the use of leaves or bark from a particular tree species did not reflect the incidence of the tree species in the immediate territory. Conclusions: This study showed that nest composition was affected by geographical location over a wide area. Variation between nests at each location was high and so it was concluded that differences in nest composition reflect individual selection of materials but evidence is such that it remains unclear whether this is deliberate to fulfil a specific role in the nest, or simply opportunistic with birds simply picking up materials with the appropriate characteristics as they find them outside their nestbox.
文摘Endemic to eastern Asia, the Japanese marsh warbler Megalurus pryeri is classified as “vulnerable” in the IUCN Red Data List. Very little information is available concerning the breeding biology of this species. From April to July 2004, we studied the breeding ecology of M.pryeri sinensis in Zhalong Nature Reserve, in northeastern China. The breeding season extended from late May until early August, with a peak in mid-June. Nest building and care of the young was undertaken primarily by females. Males defended their nesting territories, and drove away male intruders. The eggs of the Japanese marsh warbler are white, with tiny fawn spots (greatest diameter=16.88±0.86 mm,n=14); shortest diameter=12.76±0.51 mm,n=14). Clutch size averaged 5.4±1.2 (range 4-7 eggs, n=38 clutches). Incubation lasted for 10-13 days (Mean=11.9±0.8 days, n=18), with a hatching success of 59.9%. The nestling period (range 9-12 days, Mean 10.1±0.9 days, n=15) resulting in a fledgling success rate of 67.5%. Total breeding success was 41.4%. The main cause of nesting failure include human disturbance (cutting reeds), predation, and effects of grazing and flooding.
文摘Background:The Maghreb Magpie(Pica mauritanica)is an endemic North African species.Available knowledge on this species is limited to historic descriptive data with no ecological information provided.Populations continue to dramatically decline in Tunisia,where only one relic population survives.Investigating the breeding biology of this species is essential for conservation purposes.The purpose of this study was to increase our understanding of the Tunisian relic population and provide detailed data on breeding biology over two breeding seasons(2017 and 2018).Methods:This study occurred on a private farm of 650 ha,located 10 km from Dhorbania village at Kairouan Governorate,in central Tunisia.Active nests were monitored weekly during egg laying period and twice a week during hatching period.The Ivlev's electivity index was used to assess whether the frequency of use of nesting trees and bushes matched their availability in the study area.We recorded nest measurements and positions,and compared them using Wilcoxon signed-rank test.Variations of breeding parameters as number of eggs laid,hatchlings,and fledglings over years were performed using Mann–Whitney U-test andχ^(2) tests.We used a Generalized Linear Mixed Model(GLMM)to investigate how egg volume varied with clutch size and laying date.Results:We investigated clutch size,egg size,hatching and fledging success,and evaluated how these parameters varied according to laying date and nest characteristics.Clutch size averaged 5.00±0.19 but was significantly greater nest.Causes of nest failure included the depredation of nestlings by shrikes,cobras and rats(e.g.Lanius meridionalis,Naja haje and Rattus rattus),death of parents by the Black-shouldered Kite(Elanus caeruleus)and nest parasitism by the Great Spotted Cuckoo(Clamator glandarius).Clutch size,brood size and fledgling success were unaffected by laying date,nest volume and nest elevation.Egg volume decreased with laying date but was unaffected by clutch.Conclusion:Our study provides the first and only detailed data on reproductive parameters of the Maghreb Magpie in its entire geographic range(North Africa).Information gleaned from this study provides valuable information for monitoring and long-term conservation plans of the endangered Tunisian Magpie population.Additionally,our data provide an avenue of large-scale comparative studies of the reproductive ecology of the magpie complex.
