Background: The habitat features of breeding territory have important adaptive significance for the survival and reproduction of territory holders.The Chinese Grouse(Tetrastes sewerzowi) is a rare and endemic species ...Background: The habitat features of breeding territory have important adaptive significance for the survival and reproduction of territory holders.The Chinese Grouse(Tetrastes sewerzowi) is a rare and endemic species with rela?tively small distribution range and decreasing population trend.It is important to elucidate breeding territory habitat requirements of the Chinese Grouse for habitat management and conservation actions.Methods: Using radio?telemetry and field observations,we determined the core areas of 65 breeding territories of males.Two to three samples were selected in each core breeding territory as used sites and compared with nearby sites with no grouse occurrence using logistic regression.Results: Our model showed a high accuracy in prediction of core breeding territory used by males,which preferred stands with more small deciduous trees(0.5 m ≤ height < 5 m),more small willow trees(Salix spp.,0.5 m infl≤ height < 5 m),greater willow cover,and greater herb cover.The number of small willow trees had the great?estuence on males' core breeding territory selection.Dense shrubs were also chosen compared with unused sites Tall conifer trees was an important determinant in the distribution of Chinese Grouse at the landscape scale,and was relatively important in the univariate model,but not included in our final multivariable model.Conclusions: Male Chinese Grouse established territories at sites with abundant food resources.At the landscape scale,the Chinese Grouse occurred in alpine conifer forest.At the territory scale,small willow trees had the most important effect on males' core breeding territory selection.We suggest that the forest gaps in dense conifer for?est are important for improving the occurrence of willows and facilitating breeding territory establishment for the Chinese Grouse.展开更多
Background:Incubating birds must balance the conflict between thermal needs of the developing embryos and their self?maintenance needs for energy.The Chinese Grouse (Tetrastes sewerzowi) lives in high mountain conifer...Background:Incubating birds must balance the conflict between thermal needs of the developing embryos and their self?maintenance needs for energy.The Chinese Grouse (Tetrastes sewerzowi) lives in high mountain conifer forests and faces energy stress,cold environment,and predation pressure.Females might adjust incubation rhythm to adapt to these constraints. Methods:Two methods were used to investigate egg laying and incubation pattern of the Chinese Grouse;25 nests were monitored by data loggers and 12 nests by infrared video cameras. Results:Female Chinese Grouses usually laid an egg every 2 days.The incubation period was 28-31 days. Overall incubation constancy for Chinese Grouse was 93%. The females took 5.0 recesses per day and 34% of all 1696 recesses were taken in the crepuscular period. The average recess duration was 20.3 min. Females took more and shorter recesses in the latter part of incubation.The females who allocated more time to foraging had a higher reproductive success. Conclusions:Probably due to its high egg/body mass ratio,the Chinese Grouse has a long laying interval of 49 h. We suggest that,due to energy stress,females have relatively more recesses and they increase the number of recesses as incubation progresses.To compensate for the embryos'thermal needs, they extend the incubation period and shorten the recess duration in this cold environment.展开更多
Background:Forest management affects the viability of forest grouse populations,causing alterations to habitat quality.At the regional level,common targets for wood harvesting and safeguarding of specific habitats are...Background:Forest management affects the viability of forest grouse populations,causing alterations to habitat quality.At the regional level,common targets for wood harvesting and safeguarding of specific habitats are negotiated between various stakeholders.Analysing potential trade-offs between forest grouse habitats and wood production in the region could support resource-smart decision making.Methods:In this paper,we compiled trade-off curves represented as production possibility frontiers demonstrating the relationship between forest grouse habitat area and wood removal,using a Finnish forestry dynamics model and the Finnish Multi-Source National Forest Inventory.For the modelling of forest grouse habitats,a landscape-level occurrence model based on nationwide wildlife triangle census data was used.Five alternative forest scenarios in terms of wood removal were compiled for two study areas in Finland representing two different landscape structures.Results and conclusions:Results showed that impacts on forest grouse habitats were case-specific.In the southern study area,increasing the roundwood harvesting rate affected grouse habitats more strongly as forests were already fragmented for other land uses and became more spruce-dominated over time.If the maximum sustainable removal rate was implemented,predicted grouse habitat area was 55%less than in a no-removal scenario.In the eastern study area,a more heavily forested region,the decrease was far lower at 22%.Scenario results were also compared to levels of recorded(business as usual)wood removal and that envisaged by valid regional forestry programmes,and their sustainability in terms of grouse habitat area was discussed.The production possibility frontiers calculated in this study support the evaluation of the loss of suitable habitat caused by different wood harvesting rates,or vice versa,the economic cost of increasing habitat areas.展开更多
基金supported by grants from the National Natural Science Foundation of China(NSFC,31520103903)
文摘Background: The habitat features of breeding territory have important adaptive significance for the survival and reproduction of territory holders.The Chinese Grouse(Tetrastes sewerzowi) is a rare and endemic species with rela?tively small distribution range and decreasing population trend.It is important to elucidate breeding territory habitat requirements of the Chinese Grouse for habitat management and conservation actions.Methods: Using radio?telemetry and field observations,we determined the core areas of 65 breeding territories of males.Two to three samples were selected in each core breeding territory as used sites and compared with nearby sites with no grouse occurrence using logistic regression.Results: Our model showed a high accuracy in prediction of core breeding territory used by males,which preferred stands with more small deciduous trees(0.5 m ≤ height < 5 m),more small willow trees(Salix spp.,0.5 m infl≤ height < 5 m),greater willow cover,and greater herb cover.The number of small willow trees had the great?estuence on males' core breeding territory selection.Dense shrubs were also chosen compared with unused sites Tall conifer trees was an important determinant in the distribution of Chinese Grouse at the landscape scale,and was relatively important in the univariate model,but not included in our final multivariable model.Conclusions: Male Chinese Grouse established territories at sites with abundant food resources.At the landscape scale,the Chinese Grouse occurred in alpine conifer forest.At the territory scale,small willow trees had the most important effect on males' core breeding territory selection.We suggest that the forest gaps in dense conifer for?est are important for improving the occurrence of willows and facilitating breeding territory establishment for the Chinese Grouse.
基金supported by grants of the National Natural Science Foundation of China(31520103903,31172099)CAS Innovation Program and Deutsche Forschungs-emeinschaft and World Pheasant Association
文摘Background:Incubating birds must balance the conflict between thermal needs of the developing embryos and their self?maintenance needs for energy.The Chinese Grouse (Tetrastes sewerzowi) lives in high mountain conifer forests and faces energy stress,cold environment,and predation pressure.Females might adjust incubation rhythm to adapt to these constraints. Methods:Two methods were used to investigate egg laying and incubation pattern of the Chinese Grouse;25 nests were monitored by data loggers and 12 nests by infrared video cameras. Results:Female Chinese Grouses usually laid an egg every 2 days.The incubation period was 28-31 days. Overall incubation constancy for Chinese Grouse was 93%. The females took 5.0 recesses per day and 34% of all 1696 recesses were taken in the crepuscular period. The average recess duration was 20.3 min. Females took more and shorter recesses in the latter part of incubation.The females who allocated more time to foraging had a higher reproductive success. Conclusions:Probably due to its high egg/body mass ratio,the Chinese Grouse has a long laying interval of 49 h. We suggest that,due to energy stress,females have relatively more recesses and they increase the number of recesses as incubation progresses.To compensate for the embryos'thermal needs, they extend the incubation period and shorten the recess duration in this cold environment.
文摘Background:Forest management affects the viability of forest grouse populations,causing alterations to habitat quality.At the regional level,common targets for wood harvesting and safeguarding of specific habitats are negotiated between various stakeholders.Analysing potential trade-offs between forest grouse habitats and wood production in the region could support resource-smart decision making.Methods:In this paper,we compiled trade-off curves represented as production possibility frontiers demonstrating the relationship between forest grouse habitat area and wood removal,using a Finnish forestry dynamics model and the Finnish Multi-Source National Forest Inventory.For the modelling of forest grouse habitats,a landscape-level occurrence model based on nationwide wildlife triangle census data was used.Five alternative forest scenarios in terms of wood removal were compiled for two study areas in Finland representing two different landscape structures.Results and conclusions:Results showed that impacts on forest grouse habitats were case-specific.In the southern study area,increasing the roundwood harvesting rate affected grouse habitats more strongly as forests were already fragmented for other land uses and became more spruce-dominated over time.If the maximum sustainable removal rate was implemented,predicted grouse habitat area was 55%less than in a no-removal scenario.In the eastern study area,a more heavily forested region,the decrease was far lower at 22%.Scenario results were also compared to levels of recorded(business as usual)wood removal and that envisaged by valid regional forestry programmes,and their sustainability in terms of grouse habitat area was discussed.The production possibility frontiers calculated in this study support the evaluation of the loss of suitable habitat caused by different wood harvesting rates,or vice versa,the economic cost of increasing habitat areas.
