Hume's Pheasant(Syrmaticus humiae) and the Silver Pheasant(Lophura nycthemera) are two sympatric bird species at Dazhong Mountain of Yunnan Province,southwestern China.We investigated characteristics of roosting h...Hume's Pheasant(Syrmaticus humiae) and the Silver Pheasant(Lophura nycthemera) are two sympatric bird species at Dazhong Mountain of Yunnan Province,southwestern China.We investigated characteristics of roosting habitats of the two pheasants from February to April,2004 in this area.Multiple statistics,Matryoshka and a habitat classification-tree were used to analyze the selection of roosting habitats of these pheasants. The results of the habitat classification-tree indicated that several separations occurred in their macro and micro roosting habitats in the study area. The two pheasants had similar crucial requirements for and selection of ecological roosting factors,which allow them to live in the same macrohabitat.Competition between these two pheasants was avoided by separation of spatial elements,such as roosting trees and topographic characteristics.For safety strategy,Hume's Pheasant adopted primarily a way of'uneasily found habitat cover plus easy escape',while the Silver Pheasant employed a unique way of'uneasily found habitat cover'.For tactics of keeping warm,Hume's Pheasant selected mainly a method of'suitable vegetation supplemented with suitable topography',while the Silver Pheasant chose a unique man-ner of'suitable vegetation'.展开更多
Background:Disentangling the relative importance of environmental variables and interspecific interaction in modulating co-occurrence patterns of sympatric species is essential for understanding the mechanisms of comm...Background:Disentangling the relative importance of environmental variables and interspecific interaction in modulating co-occurrence patterns of sympatric species is essential for understanding the mechanisms of community assembly and biodiversity. For the two sympatric Galliformes, Silver Pheasants (Lophura nycthemera) and Whitenecklaced Partridges (Arborophila gingica), we know little about the role of habitat use and interspecific interactions in modulating their coexistence. Methods:We adopted a probabilistic approach incorporating habitat preference and interspecific interaction using occupancy model to account for imperfect detection,and used daily activity pattern analysis to investigate the cooccurrence pattern of these two sympatric Galliformes in wet and dry seasons. Results: We found that the detection probability of Silver Pheasant and White-necklaced Partridge were related to habitat variables and interspecific interaction. The presence of Silver Pheasant increases the detection probability of White-necklaced Partridge in both the wet and dry season. However, the presence of White-necklaced Partridges increases the detection probability of Silver Pheasants in the wet season, but decreases the probability in the dry season. Further, Silver Pheasants were detected frequently in the sites of high values of enhanced vegetable index (EVI) in both the wet and dry season, and in sites away from human residential settlement in the wet season. Whitenecklaced partridges were mainly detected in low EVI sites. The site use probabilities of two Galliformes were best explained by habitat variables, Silver Pheasants and White-necklaced Partridges preferred steeper areas during the wet and dry season. Both species mainly occurred in low EVI areas during the wet season and occupied sites away from the resident settlement during the dry season. Moreover, the site use probabilities of two species had opposite relationships with forest canopy coverage. Silver Pheasants preferred areas with high forest canopy coverage whereas White-necklaced Partridges preferred low forest canopy coverage in the dry season, and vice versa in the wet season. Species interaction factor (SIF)corroborated weak evidence of the dependence of the site use of one species on that of the other in the either dry or wet season.Temporally, high overlapping of daily activity pattern indicated no significantly temporal niche differentiation between sympatric Galliformes in both wet and dry seasons. Conclusions:Our results demonstrated that the presence of two species influenced the detection probability interactively and there was no temporal partitioning in activity time between Silver Pheasants and White-necklaced Partridges in the wet and dry seasons.The site use probability of two Galliformes was best explained by habitat variables, especially the forest canopy coverage.Therefore, environmental variables and interspecific interaction are the leading drivers regulating the detection and site use probability and promoting co-occurrence of Silver Pheasants and White-necklaced Partridges.展开更多
基金financed by the Wildlife Conservation Program of the State Forestry Administration of China in 2009
文摘Hume's Pheasant(Syrmaticus humiae) and the Silver Pheasant(Lophura nycthemera) are two sympatric bird species at Dazhong Mountain of Yunnan Province,southwestern China.We investigated characteristics of roosting habitats of the two pheasants from February to April,2004 in this area.Multiple statistics,Matryoshka and a habitat classification-tree were used to analyze the selection of roosting habitats of these pheasants. The results of the habitat classification-tree indicated that several separations occurred in their macro and micro roosting habitats in the study area. The two pheasants had similar crucial requirements for and selection of ecological roosting factors,which allow them to live in the same macrohabitat.Competition between these two pheasants was avoided by separation of spatial elements,such as roosting trees and topographic characteristics.For safety strategy,Hume's Pheasant adopted primarily a way of'uneasily found habitat cover plus easy escape',while the Silver Pheasant employed a unique way of'uneasily found habitat cover'.For tactics of keeping warm,Hume's Pheasant selected mainly a method of'suitable vegetation supplemented with suitable topography',while the Silver Pheasant chose a unique man-ner of'suitable vegetation'.
基金supported by the National Key Research and Development Program of China(2017YFC0503802)China Postdoctoral Science Foundation(2017M 620905)
文摘Background:Disentangling the relative importance of environmental variables and interspecific interaction in modulating co-occurrence patterns of sympatric species is essential for understanding the mechanisms of community assembly and biodiversity. For the two sympatric Galliformes, Silver Pheasants (Lophura nycthemera) and Whitenecklaced Partridges (Arborophila gingica), we know little about the role of habitat use and interspecific interactions in modulating their coexistence. Methods:We adopted a probabilistic approach incorporating habitat preference and interspecific interaction using occupancy model to account for imperfect detection,and used daily activity pattern analysis to investigate the cooccurrence pattern of these two sympatric Galliformes in wet and dry seasons. Results: We found that the detection probability of Silver Pheasant and White-necklaced Partridge were related to habitat variables and interspecific interaction. The presence of Silver Pheasant increases the detection probability of White-necklaced Partridge in both the wet and dry season. However, the presence of White-necklaced Partridges increases the detection probability of Silver Pheasants in the wet season, but decreases the probability in the dry season. Further, Silver Pheasants were detected frequently in the sites of high values of enhanced vegetable index (EVI) in both the wet and dry season, and in sites away from human residential settlement in the wet season. Whitenecklaced partridges were mainly detected in low EVI sites. The site use probabilities of two Galliformes were best explained by habitat variables, Silver Pheasants and White-necklaced Partridges preferred steeper areas during the wet and dry season. Both species mainly occurred in low EVI areas during the wet season and occupied sites away from the resident settlement during the dry season. Moreover, the site use probabilities of two species had opposite relationships with forest canopy coverage. Silver Pheasants preferred areas with high forest canopy coverage whereas White-necklaced Partridges preferred low forest canopy coverage in the dry season, and vice versa in the wet season. Species interaction factor (SIF)corroborated weak evidence of the dependence of the site use of one species on that of the other in the either dry or wet season.Temporally, high overlapping of daily activity pattern indicated no significantly temporal niche differentiation between sympatric Galliformes in both wet and dry seasons. Conclusions:Our results demonstrated that the presence of two species influenced the detection probability interactively and there was no temporal partitioning in activity time between Silver Pheasants and White-necklaced Partridges in the wet and dry seasons.The site use probability of two Galliformes was best explained by habitat variables, especially the forest canopy coverage.Therefore, environmental variables and interspecific interaction are the leading drivers regulating the detection and site use probability and promoting co-occurrence of Silver Pheasants and White-necklaced Partridges.
