From March to August in 1993 and 1994, we studied foraging strategies of rutbusbacked shrik in Nushahu in Anhui province. The shrikes mainly forage in harmland and uncultivatedland. All the food in breeding period are...From March to August in 1993 and 1994, we studied foraging strategies of rutbusbacked shrik in Nushahu in Anhui province. The shrikes mainly forage in harmland and uncultivatedland. All the food in breeding period are animals . In different breeding stagrs, food composition had changes. Three types of foragin behavior were SP (Searching and Pecking), HP (Hiding and Pouncing)and FP (Flying and Pursing). FF and FSR chang in opposed direction during breeing period; At earlybreeding period ,the shrikes had hoarding behavior.展开更多
Identifying suitable habitats of species is essential knowledge to conserve them successfully.Human activities cause the reduction of population size and habitat suitability of many species.Red-backed Shrike is widesp...Identifying suitable habitats of species is essential knowledge to conserve them successfully.Human activities cause the reduction of population size and habitat suitability of many species.Red-backed Shrike is widespread in western Palearctic.However,the population of this specie has declined in its geographical range due to the loss of suitable habitats.Therefore,it is necessary to identify its suitable habitats and factors affecting species habitat suitability and to protect its reduction population size.The aim of the present study was to identify the suitable habitat of the Red-backed Shrike and determine the most important predictors of its suitable habitat in Irano-Anatolian biodiversity hotspot.To achieve this goal,species presence points were first collected and seven environmental variables related to climate,topography and anthropogenic activities,were used to construct the species habitat suitable model.Models were built using five distribution modeling methods:Maxent,GAP,GLM,RF and GBM in sdm package.Then the models were ensemble from 5 different models and the final model was constructed.The results of this study showed that the most suitable habitats of this species are in the western and northern parts of the area of study.The mean annual temperature with 41%contribution was the most important variable in constructing the habitat suitability model for this specie.In addition,climate variables with 75%contribution were identified as the most important habitat suitability factor for this specie.Also in relation to conservation of the Red-backed Shrike species in the Irano-Anatolian region,it can be stated that the extent of distribution and presence of this specie has been extended to the northern latitudes due to climate change.As a result,the temperature and climate factor should be given special attention in the management of bird habitats in this area.展开更多
Every spring a huge number of passerines cross the Sahara Desert and the Mediterranean Sea on their way to their breeding grounds. Stopover sites after such extended barriers where birds can rest, refuel, and find she...Every spring a huge number of passerines cross the Sahara Desert and the Mediterranean Sea on their way to their breeding grounds. Stopover sites after such extended barriers where birds can rest, refuel, and find shelter from adverse weather, are of crucial importance for the outcome of their migration. Stopover habitat selection used by migrating birds depends on landscape context, habitat patch characteristics, as well as on the particular energetic conditions and needs of individ- ual birds, but it is still poorly investigated. We focused on a long-distance migrating passerine, the woodchat shrike, in order to investigate for the first time the species＇ habitat selection at a spring stopover site （island of Antikythira, Greece） after the crossing of the Sahara Desert and Mediterranean Sea. We implemented radio-tracking, color-ringing, and visual behavioral observa- tions to collect data on microhabitat use. Generalized Linear Mixed Models were developed to identify the species＇ most preferred microhabitat during its stopover on this low human disturbed island. We found that high maquis vegetation surrounded by low vegetation was chosen as perches for hunting. Moreover, high maquis vegetation appeared to facilitate hunting attempts toward the ground, the most frequently observed foraging strategy. Finally, we discuss our find- ings in the context of conservation practices for the woodchat shrike and their stopover sites on Mediterranean islands.展开更多
Background:Parental investment by birds is limited by the habitat environment,and a male parent increases its effort to reproduce in birds that live in high-altitude areas.Methods:A study of the reproductive behaviour...Background:Parental investment by birds is limited by the habitat environment,and a male parent increases its effort to reproduce in birds that live in high-altitude areas.Methods:A study of the reproductive behaviour of the Saxaul Sparrow(Passer ammodendri)and the Isabelline Shrike(Lanius isabellinus)was carried out at the Gansu An’xi Extremely Arid Desert National Nature Reserve in northwest China to determine the reproductive input of passerine species in desert habitats.Results:In Saxaul Sparrows,compared to the female parent,the male parent exhibited a significantly higher fre-quency of nest-defense behaviour(chirping and warning)during nesting,hatching and feeding periods.In addition,in comparison to the female parent,the male parent exhibited almost equal frequencies of nesting and incubation but fed nestlings significantly more times.Similar to the male sparrows,the feeding rates of the male Isabelline Shrikes were significantly higher than those of the females.The hatching rate and fledging rate of the Saxaul Sparrow on aver-age in this study were 81.99 and 91.92%,respectively,while those of the shrike were 69.00 and 96.53%,respectively.Conclusions:These two different passerine species living in the same desert environment exhibited the same trend in their reproductive investments.Adapting to desert environments is a strategy that may have evolved in passerines where male parent birds put more effort than females into reproduction to ensure high reproductive output.展开更多
文摘From March to August in 1993 and 1994, we studied foraging strategies of rutbusbacked shrik in Nushahu in Anhui province. The shrikes mainly forage in harmland and uncultivatedland. All the food in breeding period are animals . In different breeding stagrs, food composition had changes. Three types of foragin behavior were SP (Searching and Pecking), HP (Hiding and Pouncing)and FP (Flying and Pursing). FF and FSR chang in opposed direction during breeing period; At earlybreeding period ,the shrikes had hoarding behavior.
文摘Identifying suitable habitats of species is essential knowledge to conserve them successfully.Human activities cause the reduction of population size and habitat suitability of many species.Red-backed Shrike is widespread in western Palearctic.However,the population of this specie has declined in its geographical range due to the loss of suitable habitats.Therefore,it is necessary to identify its suitable habitats and factors affecting species habitat suitability and to protect its reduction population size.The aim of the present study was to identify the suitable habitat of the Red-backed Shrike and determine the most important predictors of its suitable habitat in Irano-Anatolian biodiversity hotspot.To achieve this goal,species presence points were first collected and seven environmental variables related to climate,topography and anthropogenic activities,were used to construct the species habitat suitable model.Models were built using five distribution modeling methods:Maxent,GAP,GLM,RF and GBM in sdm package.Then the models were ensemble from 5 different models and the final model was constructed.The results of this study showed that the most suitable habitats of this species are in the western and northern parts of the area of study.The mean annual temperature with 41%contribution was the most important variable in constructing the habitat suitability model for this specie.In addition,climate variables with 75%contribution were identified as the most important habitat suitability factor for this specie.Also in relation to conservation of the Red-backed Shrike species in the Irano-Anatolian region,it can be stated that the extent of distribution and presence of this specie has been extended to the northern latitudes due to climate change.As a result,the temperature and climate factor should be given special attention in the management of bird habitats in this area.
文摘Every spring a huge number of passerines cross the Sahara Desert and the Mediterranean Sea on their way to their breeding grounds. Stopover sites after such extended barriers where birds can rest, refuel, and find shelter from adverse weather, are of crucial importance for the outcome of their migration. Stopover habitat selection used by migrating birds depends on landscape context, habitat patch characteristics, as well as on the particular energetic conditions and needs of individ- ual birds, but it is still poorly investigated. We focused on a long-distance migrating passerine, the woodchat shrike, in order to investigate for the first time the species＇ habitat selection at a spring stopover site （island of Antikythira, Greece） after the crossing of the Sahara Desert and Mediterranean Sea. We implemented radio-tracking, color-ringing, and visual behavioral observa- tions to collect data on microhabitat use. Generalized Linear Mixed Models were developed to identify the species＇ most preferred microhabitat during its stopover on this low human disturbed island. We found that high maquis vegetation surrounded by low vegetation was chosen as perches for hunting. Moreover, high maquis vegetation appeared to facilitate hunting attempts toward the ground, the most frequently observed foraging strategy. Finally, we discuss our find- ings in the context of conservation practices for the woodchat shrike and their stopover sites on Mediterranean islands.
基金Financial support was provided by the National Natural Science Foundation of China(Grants 31672296 and 31172104).
文摘Background:Parental investment by birds is limited by the habitat environment,and a male parent increases its effort to reproduce in birds that live in high-altitude areas.Methods:A study of the reproductive behaviour of the Saxaul Sparrow(Passer ammodendri)and the Isabelline Shrike(Lanius isabellinus)was carried out at the Gansu An’xi Extremely Arid Desert National Nature Reserve in northwest China to determine the reproductive input of passerine species in desert habitats.Results:In Saxaul Sparrows,compared to the female parent,the male parent exhibited a significantly higher fre-quency of nest-defense behaviour(chirping and warning)during nesting,hatching and feeding periods.In addition,in comparison to the female parent,the male parent exhibited almost equal frequencies of nesting and incubation but fed nestlings significantly more times.Similar to the male sparrows,the feeding rates of the male Isabelline Shrikes were significantly higher than those of the females.The hatching rate and fledging rate of the Saxaul Sparrow on aver-age in this study were 81.99 and 91.92%,respectively,while those of the shrike were 69.00 and 96.53%,respectively.Conclusions:These two different passerine species living in the same desert environment exhibited the same trend in their reproductive investments.Adapting to desert environments is a strategy that may have evolved in passerines where male parent birds put more effort than females into reproduction to ensure high reproductive output.
