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1.
汉江中上游河道冬季水鸟共30种,隶属7目7科。其中,冬候鸟15种,留鸟8种,占73.3%,旅鸟7种。调查分析表明:独特的动物地理区系和优越的湿地环境使汉水中上游流域成为重要的鸟类越冬地及迁徙中转地,由此形成了该地特殊的冬季鸟类结构。 相似文献
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Development and characterization of continuous avian cell lines depleted of mitochondrial DNA 总被引:6,自引:0,他引:6
Réjean Morais Paul Desjardins Chanta Turmel Karen Zinkewich-Péotti 《In vitro cellular & developmental biology. Plant》1988,24(7):649-658
Summary Populations of quail and chicken cells were treated with ethidium bromide, an inhibitor of mitochondrial DNA replication.
After long-term exposure to the drug, the cell populations were transferred to ethidium bromide (EtdBr)-free medium, and cloned.
Clones HCF7 (quail) and DUS-3 (chicken) were propagated for more than a year, and then characterized. Analysis of total cellular
DNA extracted from these cells revealed no characteristic mitochondrial DNA molecule by Southern blot hybridization of HindIII-
or AvaI-digested total cellular DNA probed with cloned mitochondrial DNA fragments. Reconstruction experiments, where a small
number of parental cells was mixed with HCF7 cells and DUS-3 cells before extraction of total cellular DNA, further strengthen
the notion that the drug-treated cells are devoid of mitochondrial DNA molecules. The cell populations were found to proliferate
at a moderately reduced growth rate as compared to their respective parents, to be auxotrophic for uridine, and to be stably
resistant to the growth inhibitory effect of EtdBr and chloramphenicol. At the ultrastructural level, mitochondria were considerably
enlarged and there was a severe reduction in the number of cristae within the organelles and loss of cristae orientation.
Morphometric analysis revealed a fourfold increase of the mitochondrial profile area along with a twofold decrease of the
numerical mitochondrial profiles. Analysis of biochemical parameters indicated that the cells grew with mitochondria devoid
of a functional respiratory chain. The activity of the mitochondrial enzyme dihydroorotate dehydrogenase was decreased by
95% and presumably accounted for uridine auxotrophy.
This work was supported by a grant from the Medical Research Council of Canada. 相似文献
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The breeding avifauna of Prespa National Park is ofnational and international importance both due to itshigh richness and the internationally importantpopulations of rare species. The latter include theDalmatian (Pelecanus crispus) and Great White(Pelecanus onocrotalus) pelicans and the PygmyCormorant (Phalacrocorax pygmaeus). Populationsof national interest include Cormorant (Phalacrocorax carbo), Greylag Goose (Anseranser), Goosander (Mergus merganser), GreatWhite Egret (Egretta alba) and six otherspecies of ardeids. Among the 261 bird speciesobserved in the area of ca 250 km2 since thelate 60s, 164 breed and 41 are very rarely observed.Passage migrants and winter visitors include 91species. Twelve breeding species became extinct in theNational Park during the last 25 years and others areendangered. Raptors and aquatic birds suffered moredue to habitat and land use alterations brought aboutby the construction of an irrigation scheme.Eighty-one species observed in the area are listed asin need of special protection in Annex I of the 79/409EEC Directive and 32 of them breed. Lake Mikri Prespais of virtually no importance for wintering waterfowlsince it is frozen every winter, but the Greek part ofLake Megali Prespa, which never freezes, concentratesamong other species the 20% and 35% respectively ofthe Great Crested Grebes and Tufted Ducks wintering inGreece. 相似文献
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Recent studies have indicated that avian social behavior is influenced by olfactory cues. During the reproductive season a change in the chemical composition of uropygial gland secretion has been reported in some species and the hypothesis that olfactory signals may be produced by this gland has been proposed. To examine this hypothesis we performed two behavioral experiments to determine whether a female’s uropygial gland produce chemical signals that stimulate mating behaviors in domestic chickens. In Experiment 1 the role of the female’s uropygial gland in male mating behavior was examined by removing and examining the female’s uropygial gland. The frequency of mounts and copulations of intact male birds with sham-operated female birds was significantly higher than with uropygial glandectomized female birds. With respect to the number of waltzing that is one of the courtship displays intact males showed no significant difference between sham-operated female birds and uropygial glandectomized female birds. In Experiment 2 the relationship between male olfaction and the female’s uropygial gland was investigated using olfactory bulbectomized male birds. The number of mounts and copulations of sham-operated male birds with sham-operated female bird was significantly higher than with uropygial glandectomized female birds. In contrast olfactory bulbectomized male birds showed no significant differences in the number of mounts and copulations between sham-operated female birds and uropygial glandectomized female birds. These results indicate that intact and sham-operated male birds prefer to mate with female birds with the uropygial gland. The number of courtship waltzing of sham-operated male birds showed no significant difference. However olfactory bulbectomized male birds significantly courted to uropygial glandectomized female birds. Summarizing our results show that while anosmic males did not have any preference both intact and sham-operated male birds chose to mate with female birds having an intact uropygial gland suggesting that mate preference involves in male olfaction and that the female’s uropygial gland acts as a source of social odor cues in domestic chickens. 相似文献
6.
Patricia Manzano-Fischer Rurik List Gerardo Ceballos Jean-Luc E. Cartron 《Biodiversity and Conservation》2006,15(12):3801-3825
From February 1994 to January 2004, we studied the avifauna of a 25,000-ha area centered on the Janos-Casas Grandes Prairie
Dog Complex of Northwestern Chihuahua, Mexico. Avian diversity totalled 227 species, of which 86 (38%) were residents, 78
(35%) winter migrants, 30 (14%) summer migrants, 27 (11%) transients, and 6 (2%) accidental vagrants. Around 84 (38%) species
were observed in at least two habitat types, with riparian areas supporting the highest observed diversity of birds (112 species).
Of the 143 species observed in only one habitat type, 44 (30%) occurred in riparian areas, 35 (26%) in association with ponds
and aquatic vegetation, 28 (20%) in grasslands, 16 (11%) in the oak woodland–grassland ecotone, 12 (9%) in mesquite scrubland,
5 (3%) around human settlements, and 3 (2%) in crop fields. In particular, summer rains influenced the abundance and/or distribution
of several species in grasslands such as the long-billed curlew (Numenius americanus). The present study, which was part of a larger effort to document the merits of establishing a large biosphere reserve in
the area, confirmed the importance of the prairie dog complex and grasslands to many species of conservation concern, including
the threatened mountain plover (Charadrius montanus), a winter resident. With the␣higher-elevation habitats yet to be surveyed, the local diversity of bird species here already
places the proposed reserve among the most important protected areas in all of Mexico. The establishment of the reserve is
urgently needed, especially for the protection of grasslands and their associated fauna. 相似文献
7.
Abstract Ten species of cestodes are reported from aquatic birds in New Zealand. All are new records for the country. 相似文献
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The main processes that determine the behaviour ofheavy metals in the Scheldt estuary are tidalhydrodynamics, sediment transport,
and sorption ofheavy metals on suspended matter. The water qualitymodel WASP is applied to simulate the spatialdistribution
of five heavy metals in the estuary,under average hydrodynamic and suspended sedimenttransport regimes. First, the hydrodynamical
part ofthe model is constructed and the results are verifiedby comparison with measured water levels and flowvelocities. Secondly,
a salt transport model is set upin order to evaluate the hydrodynamical dispersivemixing characteristics. Thirdly, a suspended
sedimenttransport model is constructed and finally a transportmodel for heavy metals.
The simulated distributions of the sorbedamounts of heavy metals, suspended sediment andsalinity in the estuary agree well
with observations.The calculated profiles of dissolved and sorbedconcentrations of heavy metals in the water columnindicate
an accumulation of heavy metals in the zoneof the turbidity maximum, while closer to the sea theconcentrations diminish due
to mixing of the pollutedfluvial sediments with unpolluted marine sediments andbecause of sediment deposition in the estuary.
It canbe concluded that only a small part of the heavymetals reaches the sea.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
We assessed the capacity of three species of disturbance‐sensitive understory birds to traverse a highway (50–75 m width) and large farm clearing (250 m width), by radio‐tracking translocated individuals in central Amazonia, Brazil. Most individuals translocated across the highway (eight of nine birds) or moved within continuous forest (five of seven birds) returned to their home ranges, whereas none of five birds moved across the large clearing returned. Our results suggest that large clearings (>250 m width) can significantly reduce the movements of some understory rainforest birds. 相似文献
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M. V. Arruga E. Hadjisterkotis L. V. Monteagudo M. T. Tejedor 《European Journal of Wildlife Research》2007,53(1):47-51
The aim of the present work is to estimate the usefulness of microsatellite genetic markers analysis to characterize and analyze
the possible differences between a captive reared population and a wild one from the same species. The first sample consists
of 27 chukar partridges (Alectoris chukar) bred in one farm in Argentina. The second one is composed of 31 chukar partridges coming from a wild Cyprus population (A. chukar cypriotes). We analyzed seven microsatellite loci: MCW135, MCW225, MCW276, MCW280, MCW295, LEI31, and ADL0142. The Argentina group
showed higher genetic variation than the Cyprus did. Significant global F
IS value was found in the Argentina sample. Significant genetic differentiation exists between both groups (F
ST=0.394; p<0.01). The Argentina group did not show any signs of bottleneck. Results from Factorial Correspondence Analysis (FCA) suggest
that the 58 partridges could be split into two distinct genetic clusters (Cyprus and Argentina). Nevertheless, in the light
of PARTITION results, three Argentina individuals might be related to Cyprus. STRUCTURE is unable to assign these three animals
to any of the two groups. This could be due to a single or repeated introduction of external individuals into the original
Argentina group, so that these results would point to more than one origin for this population. This admixture of individuals
could explain the high genetic variation observed in the Argentina farm. Global F
IS value would probably be higher without these immigrations; on the other hand, these admixtures could have prevented bottlenecks. 相似文献
13.
Mexico has a megadiverse avifauna that includes many endemic elements, as well as rich sets of species ranging farther north or farther south in the Americas. This avifauna, nonetheless, has suffered considerable losses as a consequence of long‐term, intensive human activity across the landscape. We review what is known about the Mexican avifauna, specifically its diversity and endemism, and how that knowledge has and has not turned into effective conservation measures to assure the long‐term integrity of the avifauna. 相似文献
14.
Patterns of bone microstructure have frequently been used to deduce dynamics and processes of growth in extant and fossil tetrapods. Often, the various types of primary bone tissue have been associated with different bone deposition rates and more recently such deductions have extended to patterns observed in dinosaur bone microstructure. These previous studies are challenged by the findings of the current research, which integrates an experimental neontological approach and a paleontological comparison. We use tetracycline labeling and morphometry to study the variability of bone deposition rates in Japanese quail (Coturnix japonica) growing under different experimental conditions. We compare resulting patterns in bone microstructure with those found in fossil birds and other dinosaurs. We found that a single type of primary bone varies significantly in rates of growth in response to environmental conditions. Ranging between 10-50 microm per day, rates of growth overlap with the full range of bone deposition rates that were previously associated with different patterns of bone histology. Bone formation rate was significantly affected by environmental/experimental conditions, skeletal element, and age. In the quail, the experimental conditions did not result in formation of lines of arrested growth (LAGs). Because of the observed variation of bone deposition rates in response to variation in environmental conditions, we conclude that bone deposition rates measured in extant birds cannot simply be extrapolated to their fossil relatives. Additionally, we observe the variable incidence of LAGs and annuli among several dinosaur species, including fossil birds, extant sauropsids, as well as nonmammalian synapsids, and some extant mammals. This suggests that the ancestral condition of the response of bone to environmental conditions was variable. We propose that such developmental plasticity in modern birds may be reduced in association with the shortened developmental time during the later evolution of the ornithurine birds. 相似文献
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I. M. Tiunov 《Russian Journal of Marine Biology》2006,32(5):297-298
The quantity of the nesting couples of sea birds on the islands of the southern part of Amurskii Liman was determined: common heron Ardea cinerea, slaty-backed gull Larus schistisagus, black-tailed gull L. crassirostris, and sooty guillemot Cepphus carbo. 相似文献
17.
We investigated the influence of social interactions on individual foraging behavior and community structure of frugivorous birds in southern Costa Rica. Detailed observations of large, heterospecific feeding assemblages at fruiting trees revealed the existence of an interspecific dominance hierarchy, largely consistent with body and bill size. Social status influenced access to food in several ways. First, subordinate species were interrupted more and tended to have shorter foraging bouts than dominant species (n > 1.000 abouts). Second, analysis of over 7,000 videotaped head movements showed that subordinate species spent a smaller fraction of their foraging bouts actually feeding (as opposed to looking about) than did dominants. Third, when many birds were in a tree simultaneously, the foraging bouts of subordinate species were shortened; this effect was less pronounced or absent for species higher in the dominance hierarchy. Fourth, subordinate species foraged less frequently in mixed-species assemblages than did dominant species. Finally, subordinate species fed disproportionately more in the late afternoon at fruiting trees. The influence of social status appeared to manifest itself at the community level. The species composition of foraging assemblages was compared at isolated fruiting trees situated in an agricultural landscape near to (< 0.5 km) and far from (> 6 km) a large tract of primary forest. Whereas the full complement of avian frugivores foraged at the near trees, visitors to the far trees were predominantly of high social status. We discuss reasons why high social status and associated traits might confer an advantage in exploiting human-dominated habitat. 相似文献
18.
Disentangling the effects of spring anomalies in climate and net primary production on body size of temperate songbirds
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Nicolas Dubos Isabelle Le Viol Alexandre Robert Céline Teplitsky Manon Ghislain Olivier Dehorter Romain Julliard Pierre Yves Henry 《Ecography》2018,41(8):1319-1330
Body size is implicated in individual fitness and population dynamics. Mounting interest is being given to the effects of environmental change on body size, but the underlying mechanisms are poorly understood. We tested whether body size and body condition are related to ambient temperature (heat maintenance hypothesis), or/and explained by variations in primary production (food availability hypothesis) during the period of body growth in songbirds. We also explored whether annual population‐level variations of mean body size are due to changes of juvenile growth and/or size‐dependent mortality during the first year. For 41 species, from 257 sites across France, we tested for relationships between wing length (n = 107 193) or body condition (n = 82 022) and local anomalies in temperature, precipitation and net primary production (NDVI) during the breeding period, for juveniles and adults separately. Juvenile body size was best explained by primary production: wings were longer in years with locally high NDVI, but not shorter in years with low NDVI. Temperature showed a slightly positive effect. Body condition and adult wing length did not covary with any of the other tested variables. We found no evidence of climate‐driven size‐dependent mortality for the breeding season. In our temperate system, local climatic anomalies explained little of the body size variation. A large part of wing length variance was site‐specific, suggesting that avian size was more dependent on local drivers than global ones. Net primary production influenced juvenile size the most through effects on body growth. We suggest that, during the breeding season in temperate systems, thermoregulatory mechanisms are less involved in juvenile growth than food assimilation. 相似文献
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Robert J. Steidl Courtney J. Conway Andrea R. Litt 《The Journal of wildlife management》2013,77(3):445-453
Standardized protocols for surveying secretive marsh birds have been implemented across North America, but the efficacy of surveys to detect population trends has not been evaluated. We used survey data collected from populations of marsh birds across North America and simulations to explore how characteristics of bird populations (proportion of survey stations occupied, abundance at occupied stations, and detection probability) and aspects of sampling effort (numbers of survey routes, stations/route, and surveys/station/year) affect statistical power to detect trends in abundance of marsh bird populations. In general, the proportion of survey stations along a route occupied by a species had a greater relative effect on power to detect trends than did the number of birds detected per survey at occupied stations. Uncertainty introduced by imperfect detection during surveys reduced power to detect trends considerably, but across the range of detection probabilities for most species of marsh birds, variation in detection probability had only a minor influence on power. For species that occupy a relatively high proportion of survey stations (0.20), have relatively high abundances at occupied stations (2.0 birds/station), and have high detection probability (0.50), ≥40 routes with 10 survey stations per route surveyed 3 times per year would provide an 80% chance of detecting a 3% annual decrease in abundance after 20 years of surveys. Under the same assumptions but for species that are less common, ≥100 routes would be needed to achieve the same power. Our results can help inform the design of programs to monitor trends in abundance of marsh bird populations, especially with regards to the amount of sampling effort necessary to meet programmatic goals. © 2013 The Wildlife Society 相似文献