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This paper reported karyotypes of the Hobby and Kestrel collected from the suburb of Qiqihaer City. These karyotypes were
compared and analyzed, on the basis of the study of karyotypes of nine birds species in Falconiformes by Bian Xiaozhuang and
Li Qingwei. It was considered that differences in habits of birds and ecological environment not only cause falcons to differ
from others, but also differences in a genus, even within a species. This difference may result from fusion of microchromosomes. 相似文献
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Great Smoky Mountains National Park is using systemic imidacloprid to treat eastern hemlocks (Tsuga canadensis [L.] Carr.) infested with the exotic insect, hemlock woolly adelgid (Adelges tsugae Annand). This study investigated effects of these treatments on insectivorous birds and hemlock canopy arthropod assemblages in the context of food availability for insectivorous birds. Six pairs of treated and untreated hemlock sites were studied in 2007. Territories of three hemlock-associated Neotropical migratory foliage-gleaning bird species were mapped in these six sites, and relationships between bird territory density and hemlock foliar density were examined. Canopy arthropods were sampled by clipping mid-canopy hemlock branches in each paired site. Arthropods were identified to order or suborder and categorized into bird prey guilds and non-target herbivorous insect guilds. Despite being treated within the previous two years, there were no differences in hemlock woolly adelgid infestation between treated and untreated sites. This may reflect recovery or because the imidacloprid is slow-acting. Bird densities also did not differ between treated and untreated sites but were positively related to branch foliage mass, implying a preference in these birds for well-foliated hemlocks. A total of 10,219 hemlock woolly adelgids, and a total of 906 other arthropods from 16 orders were collected. There were no differences in species richness, abundance, or species composition between treated and untreated sites for total arthropods, or for immature arthropods ≥ 3 mm. In contrast, non-target herbivorous Hemiptera and larval Lepidoptera were significantly reduced in treated hemlocks. Although larval Lepidoptera are primary prey for insectivorous foliage-gleaning birds, the similarity in bird densities between treated and untreated sites suggests the birds are able to find other food resources in the mixed hemlock-deciduous stands where the study sites were located. Therefore, controlling hemlock woolly adelgid-induced defoliation through use of imidacloprid may have short-term benefits for hemlock-associated birds. While imidacloprid treatments did not appear to be currently affecting most arthropods, primary prey guilds should be monitored for long-term declines that could impact hemlock-associated birds. 相似文献
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福建漳江口红树林冬候鸟动态及保护 总被引：5，自引：1，他引：5
福建漳江口红树林自然保护区的冬候鸟共 8目 18科 5 1种 ,国家Ⅱ级重点保护鸟类 3种。该保护区最大数量发现时间为候鸟迁徙季节 (即 9月和 4月 ) ,迁徙季节鸟类的数量比越冬大 ,说明这些候鸟还有相当一部分继续南迁。保护区中越冬的鸟类共有 2 5种 ,约占总数的 1/ 2 ,不同生活型鸟类越冬所占比例有较大差异 ,其中以水禽和鸣禽最高 ,涉禽最低。同时对红树林鸟类保护提出建议 相似文献
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As forests undergo succession after major disturbance events their assemblages of birds also change. Thus the frequency and extent of wildfire or clearfelling in the landscape can potentially affect the species-richness and abundance of forest birds. We used a chronosequence approach to investigate succession of bird communities in Tasmanian lowland wet eucalypt forest, from shortly after disturbance through to old-growth forest aged approximately 200–250 years. The number of native bird species recorded per survey per site increased as a linear function of stand-age. However, succession did not involve a unidirectional transition in assemblage-composition because of differences in successional responses among individual species and also among guilds of birds that mostly inhabited different strata of the forest. This was exemplified by the crescent honeyeater, which was observed most frequently in the youngest (6–8 years) and oldest (200–250 years) forests that we surveyed, and by the superb lyrebird (introduced to Tasmania from mainland south-eastern Australia) which favoured mid-aged regrowth (42–43 years) after clearfelling. Forests aged 200–250 years had the greatest richness-per-survey of those native species that were observed mostly in the lower layer or mid-layer. However, the greatest richness-per-survey of canopy-dwelling species and the highest native species-richness across the survey period were found in forests aged around 150 years. Younger regrowth was generally less rich in birds, although regrowth in the first decade after clearfelling was the only seral stage inhabited by superb fairy-wrens. These results suggest that, in the Tasmanian lowland wet eucalypt forest landscape, species-richness of birds may be greatest when old-growth forest is interspersed with young regrowth forests. Hence for bird conservation, a challenge is to ensure that old-growth forest continues to prevail in the production forest landscape. 相似文献
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In coniferous forests of western North American, fire is an important disturbance that influences the structure and composition of floral and faunal communities. The impacts of postfire management, including salvage logging and replanting, on these forests are not well known. We compared densities and relative abundances of forest birds after fire in unsalvaged stands and stands subjected to one of two intensities of salvage logging (moderate, 30 snags retained per ha and heavy, 5–6 snags retained per ha) in mixed-conifer forests in central Oregon. We used analysis of variance with repeated measures to evaluate three hypotheses concerning the influence of different intensities of salvage on densities or relative abundances of sixteen species of birds, and two hypotheses concerning the influence of time since salvage logging on relative abundances or densities of birds. We also examined the relationship between vegetation and abundances of each bird species. We did not detect significant differences among treatments in densities or relative abundances for eight species and one genus of birds. We detected significant differences for seven species, though the patterns differed among species. Relative abundances or densities of the black-backed woodpecker (Picoides arcticus), hairy woodpecker (P. villosus), brown creeper (Certhia americana), western wood-pewee (Contopus sordidulus) and yellow-rumped warbler (Dendroica coronata) were lower in the heavy and moderate salvage treatment compared to the unsalvaged treatment, while densities of the dark-eyed junco (Junco hyemalis) and fox sparrow (Passerella iliaca) were greater in the moderately and heavily salvaged stands than in the unsalvaged treatment. We detected significant differences between years for four species of birds. Our findings suggest that both cavity-nesting and cup-nesting species respond to salvage logging, and that some species respond uniquely to habitat features influenced by salvage logging. For species that responded negatively to salvage logging, the moderate salvage intensity did not appear to mitigate the negative influence of salvage logging. Areas of unlogged burned forest appear to provide important habitat for some species of birds following forest fires. Our findings parallel those of other recent studies of these species, suggesting robust patterns that transcend particular locations. 相似文献
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为研究湖南省平江县幕阜山省级自然保护区鸟类群落结构,于2017年4月—2019年4月采用截距法对自然保护区境内鸟类资源进行调查。共记录到鸟类15目40科118种,其中国家Ⅰ级保护鸟类1种,国家Ⅱ级保护鸟类13种。雀形目鸟类物种数最多,占总数的57.6%,留鸟63种,夏候鸟28种,冬候鸟23种,旅鸟4种。 相似文献
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报道了2001年7月和2002年7月沂河流域（山东段）鸟类的数量分布状况，记录到鸟类45种，隶属于30科11目，其中食虫益鸟多达28种。提出应增加林木覆盖，改善生态环境，以便更有效地保护鸟类。 相似文献
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１９９２～１９９７年,对大围山实验林场鸟类资源进行了初步调查,共发现鸟类１１１种．隶属１４目３４科．其中东洋界种类占总种类的４６．０％;留鸟占５３．３％．属国家一级保护动物有白颈长尾雉;国家二级保护动物有白鹇、凤头鹃隼等１０种;省重点保护鸟类有环颈雉、红嘴相思鸟等１０种．其香农－维纳多样性指数为１．５１９４,均匀度指数为０．７４５５．并根据ＲＢ频率指数,确定了优势、常见、少见和偶见种．最后,就资源现状提出了保护对策 相似文献
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David I. King Richard B. Chandler Scott Schlossberg Carlin C. Chandler 《Forest Ecology and Management》2009
Many conservationists are concerned about reports of declining populations of scrub-shrub birds. Wildlife opening management, involving repeatedly burning or mechanically treating early-successional stands, is one strategy for creating habitat for these species, but this practice is costly. Some silvicultural treatments also create scrub-shrub habitat and have the advantage of potentially generating revenue, but the relative effectiveness of wildlife opening management and silviculture for creating bird habitat is not known. During 2004 and 2005, we compared scrub-shrub bird abundance, nest success, and habitat characteristics between wildlife and silvicultural openings in western Massachusetts to determine whether the habitats created by these practices are equivalent for birds. We recorded 1927 detections of 31 scrub-shrub bird species during the course of the study and monitored 368 nests. We found that although most species were present in both treatments, many differed in abundance between wildlife and silvicultural openings, including several species of high conservation concern. These differences were attributable to differences in habitat characteristics between treatments. The overall probability of a nest surviving to fledging was 0.43, and did not differ between wildlife and silvicultural openings. Our results indicate that the habitat quality of wildlife and silvicultural openings is not equivalent for scrub-shrub birds, but the two management approaches serve as complementary strategies for maintaining these declining species. 相似文献
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Max Schmid Marco Pautasso Ottmar Holdenrieder 《European Journal of Forest Research》2014,133(1):13-29
Douglas fir (Pseudotsuga menziesii (Mirb.) Franco) was first introduced to Europe from North America more than 150 years ago, was then planted on a large scale and is now the economically most important exotic tree species in European forests. This literature review summarizes the current knowledge on the effects of Douglas fir on soil chemistry, plants, arthropods and fungi. Douglas fir shapes its abiotic environment similarly to native tree species such as Norway spruce, silver fir or European beech. In general, many organisms have been shown to be able to live together with Douglas fir and in some cases even benefit from its presence. Although the number of species of the ground vegetation and that of arthropod communities is similar to those of native conifer species, fungal diversity is reduced by Douglas fir. Special microclimatic conditions in the crown of Douglas fir can lead to reduced arthropod densities during winter with possible negative consequences for birds. The ecological impacts of Douglas fir are in general not as severe as those of other exotic tree species, e.g., Pinus spp. in South Africa and Ailanthus altissima, Prunus serotina and Robinia pseudoacacia in Europe. Nonetheless, Douglas fir can negatively impact single groups of organisms or species and is now regenerating itself naturally in Europe. Although Douglas fir has not been the subject of large-scale outbreaks of pests in Europe so far, the further introduction of exotic organisms associated with Douglas fir in its native range could be more problematic than the introduction of Douglas fir itself. 相似文献
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Survival of tanoak (Lithocarpus densiflorus) and Pacific madrone (Arbutus menziesii) seedlings was studied in order to interpret succession in conifer hardwood forests and to determine ways to suppress establishment of these species. Seed protected from rodents and birds, and unprotected seed was sown in clearcuts and in conifer stands 40 to 200+ years old. Second-year survival rates of tanoak seedlings were high (50–70%) in exposed clearcuts and conifer stands. Seed predators appear to be of prime importance in limiting tanoak establishment. Survival rates of Pacific madrone seedlings on the same sites as the tanoak were low (0–8%), and many factors caused mortality. Seedlings of both species grew slowly; after 3 years, average tanoak height was only 6.0 to 14.0 cm, average madrone height 2.0 to 6.0 cm. 相似文献
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From a sample of 665 hollows found in 154 jarrah (Eucalyptus marginata) and 85 marri (Corymbia calophylla), we identified 204 hollows in 84 trees that were potentially suited to one or more of 10 species of hollow using birds and mammals. Occurrence of these hollows increased with tree age, tree size, and species (marri bore more usable hollows than jarrah) and increased amounts of dead wood in tree crowns. Hollow occurrence was most likely in trees with moderately senescent crowns with damage to intermediate sized branches, and the largest hollows were more likely to occur in more highly senescent crowns. Evidence of termite invasion at the tree butt was not related to occurrence of hollows. For all but one of the birds and mammals we considered, dead trees were no more likely than live trees to contain hollows.
Our study indicates that for the purpose of forest management planning, 130 years can be taken as the typical minimum age for the formation of usable hollows in jarrah and marri. The current minimum prescribed diameter for “habitat trees” (trees retained in logged areas to supplement existing hollows), which corresponds to a mean age of 171 years, is thus a realistic minimum size for these retained trees. We recommend raising the prescribed range of crown senescence for retained habitat trees to increase the probability of providing large hollows suited to large species such as red-tailed black cockatoo, and common brushtail possum, and maternal hollows used by smaller species. Retaining the largest trees with appropriate crown attributes will substantially increase the probability that these trees will bear usable hollows. 相似文献
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利用样线、样点法对南通市崇川区军山自然保护地和公园进行8次鸟类调查,并结合崇川区鸟类补充调查,共记录到鸟类11目34科63属90种,包括黑鸢(Milvus migrans)、凤头鹰(Accipiter trivirgatus)、日本松雀鹰(Accipiter gularis)、苍鹰(Accipiter gentilis)、红隼(Falco tinnunculus)、小鸦鹃(Centropus bengalensis)6种国家II级保护物种;统计分析表明,军山自然保护地与公园景区鸟类群落存在一定差异,物种丰富度更高,占整个崇川区的60%,而公园景区占比在22.22%与42.22%之间;与公园景区相比,军山自然保护地鸟类群落稳定性更高,而公园景区个别种类鸟数量较高,群落稳定性相对较差;在城市环境中,军山自然保护地可作为鸟类避难所和种源地,在保护城市生物多样性方面具有重要作用;管理部门可结合鸟类季节动态,错峰进行公园景区管理活动,如减少5—8月夏季繁殖期的喷药、剪枝等活动,以保护城市生物多样性。 相似文献
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Early nineteenth-century studies of variation in the genus QuercusL., particularly those relating to Pedunculate and Sessile oakby Lasch and Greville, illustrate the confused situation thatawaited the forest botanist. Attempts of that period and laterto explain this condition led to the general acceptance of atheory of unlimited hybridization and introgression betweenthe two species. Experimentation and observations between thethirties and fifties of the present century by Dengler, Høeg,Jones, and others demonstrate the weakness of this popular concept—hence the controversy. More recent investigations by Johnssonand Krahl-Urban, supported by the biometric research of Cousens,Carlisle, and Brown, have helped in the production of a moreaccurate picture of the form and extent of hybridization. Agreat deal still remains to be done to elucidate the naturalfrequency of F1 hybrids, and backcrossea in different regions.The karyotypes of both species and hybrids have still to bedefined. 相似文献