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11.
ABSTRACT Gamebird chick survival is dependent on invertebrate availability, and the ability to access insect prey is an important characteristic defining brood habitat quality. Different mixes of warm-season grasses and forbs were established to improve the habitat quality of fields enrolled in the Conservation Reserve Program (CRP) for gamebirds in the Southern Plains. We analyzed the feeding ecology of human-imprinted, 4- to 10-day-old ring-necked pheasant (Phasianus colchicus) and northern bobwhite (Colinus virginianus) chicks in wheat fields and 4 types of conservation practices (CP) fields enrolled in CRP (CP10, improved CP10, CP2, and CP25) in western Kansas, USA, during June and July, 2004 and 2005. Foraging rates were greatest for bobwhite chicks in improved CP10 and CP25 fields and greatest for pheasant chicks in CP10 and CP25 fields. Vegetation characteristics such as bare ground cover appear to have a significant impact on insect selection, because the diet was more diverse for both species in fields with more bare ground. The CP25 fields provided the best combination of mobility and diet breadth for both species. Although herbicide-treated wheat fields had low feeding rates, we determined non-herbicide-treated fields (i.e., weedy wheat) provided easy mobility and feeding rates similar to CRP fields. We suggest that management of vegetation to benefit gamebirds does not affect species equally. Feeding rates of bobwhite chicks were sensitive to vegetation-influenced mobility. Management of CRP fields for both pheasant and bobwhite chicks can be reconciled by practices that permit more open space at ground level, such as light disking or burning, to permit easier movement for chicks.  相似文献   
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13.
We isolated eight microsatellite loci from genomic DNA in Elliot's pheasant Syrmaticus ellioti using streptavidin‐coated magnetic beads. In the analyses of 53 individuals sampled, these loci displayed polymorphism varying from six to nine alleles per locus and observed heterozygosities ranging from 0.174 to 0.430. The results suggested that these novel microsatellite markers could become useful molecular tools for genetic studies of S. ellioti.  相似文献   
14.
血雉繁殖期活动区与栖息地特征   总被引:4,自引:1,他引:3  
采用无线电追踪技术并结合野外观察,对血雉繁殖期活动区与栖息地特征进行了研究。孵卵期(5月)雄鸟的活动区面积为31.90hm^2,雌鸟为8.67hm^2。育雏期一个家族的活动区面积为15.45hm^2(6月)和17.33hm^2(7月)。繁殖季节相邻两个繁殖对的活动区有重叠。血雉繁殖季节喜欢在北坡和东坡活动,这种选择与食物的分布有关。倒木在繁殖期栖息地选择中占有一定地位。用多元总体假设检验、单变量F检验及主成分分析法对实验样方与对照样方间进行了比较分析。结果表明,繁殖期喜选择山脊附近下层空间较为斤阔的灌木林或林间空地。  相似文献   
15.
暂时与群体分离的个体藏马鸡的反捕食警戒   总被引:3,自引:0,他引:3  
卢欣 《动物学报》2004,50(1):32-36
通过与同伴分担捕食风险 ,生活在稳定群体中的个体动物可以获得长期的适合度利益 ,但同时它们不得不承担食物竞争所带来的潜在代价。这种代价常常取决于食物资源的类型。当好的食物资源出现时 ,一些个体可以离开群体而独享这种资源。了解这些临时游离者如何组织其反捕食行为 ,在进化生态学上是有意义的。藏马鸡 (Crossoptilonharmani)是西藏雅鲁藏布江中游高山灌丛植被的一种典型的非繁殖季节集群鸟类。野外观察表明 ,为了独享好的食物资源 ,一些个体常常远离当前群体的活动范围。分离事件更可能发生于大的群体 ,但其发生率与参与者的数量呈负相关 ;而参与分离的个体愈多 ,分离持续的时间就愈长。分离者的个体警惕水平随着临时群体大小的增加而下降 ,遵从在其它自然大小鸟类群体所发现的一般性规律。分离行为的发生和持续时间被认为是个体对当前食物回报和捕食风险进行权衡的结果。这种利益 -代价权衡也可以解释藏马鸡所具有的强烈集群行为  相似文献   
16.
Egg white proteins, hemoglobin, serum proteins and enzymes from Phasianus colchicus have been examined by starch gel electrophoresis. All three genetic parameters, mean proportion of loci polymorphic per population (P), mean numbers of alleles per locus (A), and mean proportion of loci heterozygous per individual (H), are given. Comparison were made between the proteins of the related species Coturnix coturnix japonica, and the variation of pheasant proteins is discussed in connexion with the genetic structure of the population studied.  相似文献   
17.
Reciprocal immunization between parents of an Illinois family of ring-necked pheasants, Phasianus colchicus, resulted in antisera detecting two pairs of alloantigens segregating among 13 progeny. The four alloantigens were tentatively designated as 1 and 2, transmitted antithetically by the sire, and 3 and 4, transmitted antithetically by the dam. Genetic segregation occurring in second-generation progeny demonstrated that these two pairs of antigens belonged to a single genetic system. This alloantigen system was shown to correspond serologically to the major histocompatibility complex (MHC) of the chicken by cross-reactivity of the antigens of this system with specific subregional chicken MHC reagents, appropriately absorbed with erythrocytes of individual pheasants. These four haplotypes of the pheasant MHC were subsequently designated as MhcPhco-B1, MhcPhco-B2, MhcPhco-B3 and MhcPhco-B4. Traditional immunogenetic analysis of 30 pheasant families produced in this study disclosed a minimum of 14 pheasant haplotypes of this alloantigen system (MHC) to be segregating in the population under evaluation.  相似文献   
18.
白冠长尾雉的越冬生态   总被引:6,自引:0,他引:6  
白冠长尾雉的越冬生态方成良丁玉华(河南省信阳林业学校,464031)Over_WinteringEcologyoftheWhite_crownedLong_TailedPheasant.FangChengliang,DingYuhua(Xinyang...  相似文献   
19.
白鹇海南亚种的生态和现状   总被引:9,自引:0,他引:9  
海南白鹇是仅分布于我国海南岛的特殊的白鹇海岛亚种。其结群个体少;雏鸟孵出后,每群雏数少;亲鸟损失严重,有极其罕见的纯雏群现象;种群繁殖力低,出生率仅77.5%;保护区核心区种群密度1978年20.2只/km~2,1992年12只/km~2。天敌、人类危害是种群数量严重下降的主要原因。目前全岛有白鹇分布的残存林区面积仅740km~2,乐观估计白鹇数量已不足8800只,白鹇海南亚种已处于渐危至濒危级别,必须尽快采取有效的保护措施。  相似文献   
20.
The foraging habitat selections of brown-eared pheasant (Crossoptilon mantchuricum) and the common pheasant (Phasianus colchicus) were studied in Huanglongshan Nature Reserve Shaanxi, China. Foraging habitat characteristics were measured on the basis of expected differences between species at 183 sites from November to December 2006 and January 2007. The results showed that both species selected foraging habitats with altitude (<1200 m), conifer forest, half sunny and half shady slope, sunny slope, density of trees (<5 individuals/100 m2), cover of shrub (>50%), visibility class (<10%) and distance to water source (<300 m). However, the brown-eared pheasant selected habitats with cover of trees (30–50%), middle or lower slope location, distance to edge of woods (<300 m) and human disturbance (<500 m), and the selection on density of shrub was not observed, compared to the selections on cover of trees (<30%), lower slope location, distance to edge of woods (<500 m) and human disturbance (<300 m), and density of shrub (>500 individuals/100 m2) for common pheasant. We also found that the common pheasant avoid predators by concealment whereas brown-eared pheasant evade predations by running away strategy.  相似文献   
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