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1.
We studied the size and productivity of white stork (Ciconia ciconia) populations in eight study sites in Poland. The number of nesting pairs and the average number of chicks fledged per pair fluctuated over time, and the studied populations differed in the variance of both breeding success and number of breeding pairs. The variance of breeding success (both for the mean number of chicks and the proportion of successful nests) and the variance of the number of breeding pairs was not correlated with the extent of stable habitats (pastures, meadows, wetlands), other habitats (farmland), or with local population trends over time. We found a non-linear symmetrical relationship between annual mean reproductive success and its variance but only when considered as the proportion of successful nests (i.e., when individual nests are coded as a binary value: 0, no success; 1, success). No such relationship existed when success was expressed as the number of fledged chicks. Although a positive significant correlation occurred between fledgling numbers (discrete data) and the proportion of successful nests (binary data), we believe that the use of only binary data will be inadequate in more detailed analyses, such as population viability analysis.  相似文献   

2.
In 2002 and 2003, blood samples from white stork (Ciconia ciconia) chicks were examined for the presence of antibodies against Listeria monocytogenes. Listeria antibodies were detected in 121 (59%) of 205 chick samples. The probability of Listeria antibodies being present increased with chick age; chicks detected with Listeria antibodies were in better condition than those without the bacterium.  相似文献   

3.
马立名  殷秀琴 《蛛形学报》2011,20(2):119-122
在长岭草原共采到中气门螨9科15属20种。优势种为胸前下盾螨Hypoaspis praesternalis Willmann,1949,螨数和分布生境数最多,常见种有10种,稀有种为9种。在调查的20个生境中,羊草杂类草生境螨数和螨种数最多,碱茅生境没有采到螨,其余18个生境都采到不同数量的螨。  相似文献   

4.
During satellite-tracking investigations of 140 white storks (Ciconia ciconia), one individual, the long-term world record holder among birds, was followed along 12 migratory journeys over a period of 10 years. This long-term study confirms what previous several-year tracking studies of white storks had indicated: there can be great variability from year to year in the choice of winter quarters as well as in the routes and times of migration, intermediate destinations and stop-over periods, but constancy of winter quarters and migration routes is also possible. The variability may well be caused by external factors, of which food supply is probably predominant.Communicated by F. Bairlein  相似文献   

5.
We examined breeding dispersal directions in the white stork (Ciconia ciconia), a migratory bird breeding in large parts of Europe. We asked whether and how the direction of the major spring/autumn migration route (from south-east to north-west and vice versa) affects breeding dispersal directions. Breeding dispersal directions were clearly nonrandomly distributed and were influenced by the major spring migration direction, leading to a bias toward south-eastward and north-westward breeding dispersal.  相似文献   

6.
7.
匡毅 《蛛形学报》2011,20(1):25-26
描述簇毛巨螯螨Maerocheles penicilliger(Berlese,1904)雄螨。  相似文献   

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9.
Mites are often overlooked as vectors of pathogens, but have been shown to harbor and transmit rickettsial agents such as Rickettsia akari and Orientia tsutsugamushi. We screened DNA extracts from 27 mites representing 25 species of dermanyssoids for rickettsial agents such as Anaplasma, Bartonella, Rickettsia, and Wolbachia by PCR amplification and sequencing. DNA from Anaplasma spp., a novel Bartonella sp., Spiroplasma sp., Wolbachia sp., and an unclassified Rickettsiales were detected in mites. These could represent mite-borne bacterial agents, bacterial DNA from blood meals, or novel endosymbionts of mites.  相似文献   

10.
描述短毛下盾螨Hypoaspis brevipilis Hirschmann,1969雌螨与后若螨。  相似文献   

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