Coexistence Mechanism Of Sympatric Distribution Of Pheasants

Food,habitats and spatial distribution are the main drivers for the coexistence of co-distributed species.Current studies have mainly investigated the coexistence of sympatric species from multiple dimensions such as habitat selection,activity rhythms,and resource utilization.However,few studies have simultaneously examined the ecological niche delineation of sympatric related species across different ecological dimensions.Comparative studies of ecological niches at finer scales and in different dimensions are necessary to better understand the coexistence among these sympatric species with similar ecological niches.Over the period of 2017-2021,210 camera traps were deployed and installed in the Wuyi Mountains to monitor the status of pheasant species.Based on the monitoring data from the camera traps,indices of diversity and daily activity rhythms of various pheasant species were calculated.With the information gathered through field measurements and Arc GIS,habitat use patterns of four pheasant species were analyzed using single species occupancy models during breeding and nonbreeding periods.Additionally,the coexistence patterns of four pheasant species within the same geographic area of the Wuyi Mountains were systematically evaluated in respect of temporal and spatial ecological niches.The main findings were as follows:1)The survey results showed that a total of six pheasant species were monitored in the Wuyi Mountains from 2017 to 2020,including the Yellow-billed Tragopan(Tragopan caboti),Chinese Barred-backed Pheasant(Syrmaticus ellioti),silver pheasant(Lophura nycthemera),White-browed Hill Partridge(Arborophila gingica),Koklass Pheasant(Pucrasia macrolopha)and Chinese Bamboo Partridge(Bambusicola thoracica).The silver pheasant had the highest shooting rate(90.27%)and relative abundance index(66.75%).2)The results of temporal ecological niche analysis showed that the temporal ecological niche overlap was larger,and competition was intense between the silver pheasant and the yellow-bellied tragopan,the Chinese bamboo partridge,and the white-browed hill partridge.While the temporal ecological niche overlap between the silver pheasant and the white-browed hill partridge,the silver pheasant and the Chinese bamboo partridge,the yellow-bellied tragopan and the Chinese bamboo partridge and the white-browed hill partridge and the yellow-bellied tragopan was smaller and competition between them was lower.3)Interspecific association studies between the four pheasant species revealed a highly significant positive ecological association between the yellow-bellied tragopan and the white-browed hill partridge,indicating that the two species share similar habitat preferences and high encounter rates and niche overlaps.The negative ecological association between the silver pheasant and the Chinese bamboo partridge was highly significant,indicating that their overlapping ecological niches and encounter rates were low,and their interspecific competition was weak.The ecological niche results of the four pheasant species in terms of elevation and habitat use showed that the ecological niche width of the silver pheasant was the largest and significantly different from the other three pheasants,and the ecological niche overlap of the yellow-bellied tragopans,white-browed hill partridge and Chinese bamboo partridge were all nested in the ecological niche area of the silver pheasant.4)A single-season occupancy model analysis was conducted for four pheasant species: The results showed that the occupancy rate of the silver pheasant was mainly influenced by shrub cover and vegetation type during the breeding season,while shrub cover and slope were the key factors affecting the occupancy rate of the silver pheasant during the non-breeding season,and altitude was always the main factor affecting the detection rate of the silver pheasant in both seasons.The occupancy rate of yellowbellied tragopans in breeding and non-breeding seasons was not affected by covariates,while the detection rate was mainly influenced by elevation.The occupancy rate of white-browed hill partridge was influenced primarily by altitude,and the covariates did not affect the detection rate of white-browed hill partridge.The occupancy rate of Chinese bamboo partridge in breeding and non-breeding seasons was not affected by covariates,while the detection rate in the breeding season was mainly influenced by altitude but not in the non-breeding season.5)Pheasant species achieve partitioning of resources through temporal and spatial scales,and this differentiated behavior can effectively alleviate interspecific competitive pressures and thus achieve coexistence.Pheasants of four species inhabiting the Wuyi Mountains differ in their habitat use,with lower human disturbance and reduced predation pressure at higher elevations potentially facilitating breeding.In addition,steep slopes help pheasants to react promptly to predators,and they can escape from predators by rushing down the slope quickly,thus reducing the risk of predation.Human activities at middle and low altitudes have intensified competition for resources of pheasant species in the Wuyi Mountains.To minimize the effect of domesticated animals on vegetation and cognate species,managers of protected areas should develop sound management plans to control the increase in domesticated animal.