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1.
Twelve polymorphic microsatellite loci were developed for Dendrocopos medius. Polymorphism was assessed for 27 individuals from the southwesternmost population of this woodpecker species. The number of alleles per locus ranged from three to seven, with observed heterozygosity values from 0.444 to 0.852. Genotypic frequencies conformed to Hardy-Weinberg equilibrium, and no evidence for linkage disequilibrium was observed. Multilocus genotypes resulting from this set of markers will be useful to determine genetic diversity and differentiation within and among habitat patches inhabited by D. medius. Three of the loci were polymorphic for Picoides articus.  相似文献   
2.
Capsule Woodland birds were significantly less likely to occur in gardens in years of high beechmast crop.

Aim To test the hypothesis that woodland species that feed on beechmast will have significantly lower occurrence rates at garden feeders in mast years.

Methods Weekly winter occurrence rates at garden feeders between 1970/71 and 1999/2000 for 40 species were analysed in relation to annual beechmast abundance, classified into low, medium and high years. A repeated-measures logistic regression model was used to assess whether beechmast abundance explained further significant variation additional to underlying seasonal and annual trends.

Results Seven species that commonly feed on beechmast showed significantly lower occurrence in gardens in years of highest beechmast abundance: Great Spotted Woodpecker Dendrocopos major, Woodpigeon Columba palumbus, Great Tit Parus major, Coal Tit Periparus ater, Nuthatch Sitta europaea, Jay Garrulus glandarius and Chaffinch Fringilla coelebs. Blackbird Turdus merula and Siskin Carduelis spinus, which showed similar significant patterns, are likely to take beechmast as elements of their diet. Pied Wagtail Motacilla alba was the only insectivorous species to show significant effects, but occurrence was lowest in years of intermediate beechmast abundance. For the latter species, this may have been due to confounding effects of temperature, but there were no such confounding effects of either temperature, or the number of bird feeders provided in gardens, for the other nine species.

Conclusion Use of artificial food sources by birds in gardens is influenced by resources in the surrounding countryside, suggesting that food provided in gardens may play a significant part in the population dynamics of these species, that population monitoring without consideration of the garden habitat may be deficient, and that volunteer-based garden bird recording may provide data that can be used as an indicator of changes in the wider countryside.  相似文献   
3.
In birds, feathers and faeces can be used as a source of DNA for genetic analyses. If the materials are derived from an absentee bird(s), however, the species must first be identified. Here, we developed four pairs of primers for amplification of mitochondrial 12S ribosomal RNA fragments in the black woodpecker Dryocopus martius, a vulnerable species in Japan, and three other sympatric woodpeckers including Dendrocopos leucotos, D. major and Picus awokera. Because each primer pair gave a PCR product in only one of the examined species, these primer sets will be useful in identifying the species of woodpeckers.  相似文献   
4.
In a comparative study we investigated woodpecker abundance in forest landscapes with different proportion of native pine forest and spruce plantations in western Norway. In 100 circular study plots of 100ha each we recorded 38 white-backed –Dendrocopos leucotos, 22 grey-headed –Picus canus, 13 great spotted –Dendrocopos major, 6 green –Picus viridis, and 2 lesser spotted –Dendrocopos minor woodpeckers in the breeding season. The mean number of recorded woodpecker species peaked at 20–40% spruce plantations. The two most common species in the study, the white-backed and the grey-headed woodpeckers are both Red-listed species in Norway and among the rarest woodpeckers in Europe. The white-backed woodpecker preferred plots with higher than average proportions of standing dead trees and deciduous trees, and low proportions of spruce plantations in the plots. The grey-headed woodpecker preferred plots in the western (coastal) parts of the study area with presence of large aspen Populus tremula trees. Logistic regression models did not reveal any clear threshold values with respect to proportion of spruce plantations in plots, although both woodpecker species were extremely rare in plots with >60% spruce plantations. We recommend spruce plantations to be kept at moderate levels to ensure viable populations of woodpeckers in western Norway.  相似文献   
5.
斑块质量对大斑啄木鸟冬季觅食行为的影响   总被引:2,自引:0,他引:2  
为了解大斑啄木鸟(Dendrocopos major)冬季对食物斑块的利用对策,2011年1月和2012年2~3月,在内蒙古乌拉特前旗的农田防护林中,采用目标动物取样法和全事件记录法,观察了大斑啄木鸟在食物斑块的觅食行为,利用主成分分析方法对斑块质量进行评价,通过比较不同质量斑块中大斑啄木鸟的觅食频次、停留时间、觅食成功频次及觅食成功率等指标,分析斑块质量对其觅食行为的影响。结果显示,在不同质量斑块中大斑啄木鸟的觅食频次、停留时间、觅食成功频次差异都极显著,但觅食成功率差异不显著;除停留时间外,不同性别间觅食差异不显著。大斑啄木鸟的觅食频次、停留时间、觅食成功频次与斑块质量呈显著正相关,觅食成功率与斑块质量相关性不显著。大斑啄木鸟倾向于在质量水平高的斑块觅食,表现为在这些斑块停留时间更长、往返次数更频繁;但觅食成功率不受斑块质量影响,这可能是大斑啄木鸟适应不同觅食环境的一种生存本能。  相似文献   
6.
Many species are locally adapted to decreased habitat quality at their range margins, and therefore show genetic differences throughout their ranges. Under contemporary climate change, range shifts may affect evolutionary processes at the expanding range margin due to founder events. In addition, populations that are affected by such founder events will, in the course of time, become located in the range centre. Recent studies investigated evolutionary changes at the expanding range margin, but have not assessed eventual effects across the species' range. We explored the possible influence of range shift on the level of adaptation throughout the species' total range. For this we used a spatially explicit, individual‐based simulation model of a woodland bird, parameterized after the middle spotted woodpecker ( Dendrocopos medius) in fragmented habitat. We simulated its range under climate change, and incorporated genetic differences at a single locus that determined the individual's degree of adaptation to optimal temperature conditions. Generalist individuals had a large thermal tolerance, but relatively low overall fitness, whereas climate specialists had high fitness combined with a small thermal tolerance. In equilibrium, the populations in the range centre were comprised of the specialists, whereas the generalists dominated the margins. In contrast, under temperature increase, the generalist numbers increased at the expanding margin and eventually also occupied the centre of the shifting range, whereas the specialists were located in the retracting margins. This was caused by founder events and led to overall maladaptation of the species, which resulted in a reduced metapopulation size and thus impeded the species' persistence. We therefore found no evidence for a complementary effect of local adaptation and range shifts on species' survival. Instead, we showed that founder events can cause local maladaptation which can amplify throughout the species' range, and, as such, hamper the species' persistence under climate change.  相似文献   
7.
ABSTRACT.   We present the first report of population density and home range estimates for the Chestnut Wood-quail ( Odontophorus hyperythrus ), an endemic and nearly threatened species of the Colombian Andes. Density estimates were obtained using playbacks and spot mapping and point transect methods. Home range sizes were estimated by radio tracking five wood-quail. Estimated densities varied from 0.3 to 0.4 groups per hectare. These densities are similar to those reported for other mountain wood-quail, but higher than those for lowland wood-quail and other species in the family Odontophoridae. Estimates of home range size varied from 2.6 to 9.0 hectares per group, and seemed to be correlated with group size. We also found evidence of overlap in the home ranges of neighboring groups. Population densities may vary with factors such as habitat type, but our estimates allow a first approximation of the population sizes of Chestnut Wood-quail in forest fragments.  相似文献   
8.
<正>2013年4月24日、6月9日和6月27日,在青海省三江源国家级自然保护区玛可河地区友谊林场(32°40′N,101°2′E,海拔3 240 m)、格日则沟原始林区(32°44′N,101°10′E,海拔3 480 m)针叶树干以及玛可河干流岸边(32°40′N,100°57′E,海拔3 270 m)杨树上共观察到7只?形目鸟类,并拍摄到清晰数码照片。该鸟体形中等,  相似文献   
9.
2011年6~8月,在北京市野生动物救护中心露天笼舍内,采用瞬时扫描法对笼养条件下的4只大斑啄木鸟(Dendrocopos major)行为时间分配和活动节律进行了研究,利用单因素方差分析来说明不同性别大斑啄木鸟间行为时间分配差异以及研究对象在日间不同时间段行为节律差异.结果显示,笼养条件下大斑啄木鸟的各种行为活动具有一定的时间分配特点和日行为节律.大斑啄木鸟的行为主要表现为休息和飞行走动,占全部行为的36.24%和26.96%,其次为觅食行为,占17.69%.除觅食、理羽和其他行为外,雌雄间行为时间分配差异不显著(P>0.05).大斑啄木鸟昼间活动的高峰期出现在上午,中午有午休现象,日间行为节律明显.飞行走动、休息、理羽、跳跃行为的发生频次在雌雄间无显著差异(P>0.05),而雄性觅食的发生频次显著地大于雌性的(P<0.05).  相似文献   
10.
同域分布3种啄木鸟冬季取食的生态位差异   总被引:1,自引:0,他引:1  
戎可  司雨蕙  潘麒嫣  王欢 《生态学报》2018,38(23):8314-8323
为了掌握黑啄木鸟、三趾啄木鸟和大斑啄木鸟的冬季取食行为特征,特别是三者之间取食生态位的差异,于2016年1月5-13日,在黑龙江省凉水国家级自然保护区以样线法结合样方法对3种啄木鸟的取食生境和取食行为进行了系统调查,收集了15个生境和行为特征变量数据。共布设45条样线,484个对照样方,收集312组啄木鸟取食数据,其中黑啄木鸟73组,三趾啄木鸟97组,大斑啄木鸟142组。多变量回归树和多分类逻辑斯谛分析结果显示,3种啄木鸟在所调查的15项特征上存在显著分异。采用基于利用-可利用方法的Bailey''s方法和双因子方差分析,分别对3种啄木鸟的生境选择和行为特征进行分析,结果显示:黑啄木鸟和三趾啄木鸟偏好在郁闭度较高的原始云、冷杉林中取食,而大斑啄木鸟则随机地在各种林型、生境中取食。黑啄木鸟、三趾啄木鸟多在树干取食,黑啄木鸟更常在倒木上取食,而大斑啄木鸟则多在树冠层取食。黑啄木鸟基本只在主干上凿洞,其他两种特别是大斑啄木鸟则可以在侧枝上取食。与黑啄木鸟和大斑啄木鸟凿洞取食昆虫不同,三趾啄木鸟多通过扒去树皮获得食物。黑啄木鸟的取食树基本为死树,单树取食时间最长,大斑啄木鸟多在活树上取食,单树取食时间最短,经常更换取食树,而三趾啄木鸟的取食树则死活参半,单树取食时间也较长。黑啄木鸟的冬季取食行为节律表现为双峰形,日出后和日落前各有一个活动高峰,其他两种则于白天持续取食。3种啄木鸟取食生境和行为生态位的差异,使它们能够更有效地利用有限的食物资源,共存于同一森林。  相似文献   
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