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1.
采用生境套娃方法反映水禽——东方白鹳生境需求的层级系统基础上,利用GIS技术建立定量化分析模型,深入探讨了小三江平原生境丧失对东方白鹳生境空间分布的影响。结果显示:与初始状态1954年相比,东方白鹳繁殖生境丧失了81.9%,平均斑块面积缩小了88%;同时,生境面积的丧失是伴随生境破碎化过程发生的。1983之后生境破碎化明显加剧,到2005年生境连通度显著降低,生境处于高度破碎化状态。研究表明,生境丧失对东方白鹳繁殖生境的影响不仅取决于关键生境要素的变化,生境空间异质性改变更为重要。 相似文献
2.
Population dynamics of the White Stork Ciconia ciconia were studied in Charente-Maritime, France from 1978 to 1996, during which time the number of breeding pairs increased from one to 44. Modal age at first return and first breeding were 2.4 and 3.4 years, respectively. White Storks produced an average of 3.2 fledglings per nest. The average number of fledglings per nest decreased with increasing nest density, probably because of an increase in the number of interactions between breeding birds. Nests surrounded by marshes had slightly greater productivity than nests on peripheral sites. Individual White Storks followed an annual breeding cycle and attempted to breed in 97% of seasons once mature. Nest-site and mate fidelity were high (88 and 83%, respectively). Immigration rate was nearly twice that of emigration during the last few years of the study and recruitment was close to 30%, although underestimated. We modelled survival and recapture probabilities using capture-mark-recapture methods. Adult survival was found to be dependent on age, but not sex. Survival of younger birds varied greatly over the years, whereas survival of older birds was relatively constant and averaged 78%. Survival rates of young birds wintering in the Sahel zone were positively linked to the amount of rainfall in their wintering area. The proximate reason for the population increase was probably immigration of birds from other European countries, probably encouraged by a high adult survival rate. Ringing recoveries indicate that some birds winter in Spain and the high adult survival rate may reflect a change in migratory pattern in recent years. Finally, reproductive success was relatively high during the study. 相似文献
3.
To understand how a large soaring bird, the White Stork Ciconia ciconia , copes with energy constraints, we compared changes in body mass in 14 captive adult storks with the body composition of 12 free-ranging adult storks found dead from accidents. The captive storks, already in an enclosure for several years, were fed ad libitum . They were weighed daily for 1.53.5 years using an automatic device. The bodies of the accidentally killed storks were analysed to determine total water, lipid, protein and ash contents, and to assess the biochemical composition of certain organs. Females were on average 20% lighter and 24% smaller than males, but the body mass of the sexes varied in parallel throughout the year. Body mass peaked in December and January (2530% above minimal body mass), due essentially to large fat stores in subcutaneous and abdominal adipose tissues. Body mass and body lipid rapidly decreased from February to June, whether the storks reared chicks successfully or not, and remained minimal for a few days into July. In contrast to birds using flapping flight, no variation in body protein or pectoral muscle protein was observed while breeding, even though the moult occurred then, nor in August, before the time when wild storks migrate. An endogenous regulation of body fuels is discussed. 相似文献
4.
In the mid 1970s, the breeding populations of the migrant White Stork Ciconia ciconia were close to extinction in the northeastern region of France (Alsace). A re-introduction project was implemented, resulting in the year-round settlement of some individuals in the region, which rely on additional food supplied by humans during the winter. Today, both resident and migrant birds breed in the same areas and take food from rubbish dumps and humans (farmers). The effects of these anthropogenic influences, altering Stork behaviour, on Stork reproductive success are not known. The aim of this study was to test the influence of bird status (resident vs. migrant) and food availability (control nests vs. nests that benefit from high food supply) on reproductive success. In control nests, the mean laying date was earlier in resident than in migrant White Storks. There was also a clear seasonal decline in clutch size. For all nests, the numbers of eggs and hatchlings were higher in resident birds than in migrants, which can be attributed to the earlier breeding of resident Storks. The large broods of resident birds showed a high mortality rate, leading to the same fledgling success (fledglings/hatchlings) and number of fledglings as in migrants. Fledgling success and the number of fledglings were higher for nests close to a reliable food supply. In summary, although resident birds can breed earlier and produce more eggs than migrants, we found no advantage in terms of number of fledglings. The higher mortality rate of chicks found in pairs with a large brood could be caused by the deterioration of their habitat. Thus, the year-round settlement of Storks may not present a biological advantage if the quality of their habitat is not guaranteed by the conservation of their grasslands. 相似文献
5.
The population of the White Stork Ciconin ciconia in Alsace (northeastern France) has decreased considerably since 1961. Using recent captureerecapture models, we analysed resighting data on ringed birds resulting from a long-term ringing programme carried out in 1947–1985. Time-dependence and age-dependence in annual survival rates are examined with reference to environmental variables in the Sahel wintering area. Our results show a decrease in adult annual survival rate linked to the severity of the drought in the Sahelian zone. 相似文献
6.
CapsuleFood independently affects both laying date and clutch size, suggesting that seasonal decline in clutch size is related to a decrease in food availability. Aim To test the effect of food abundance on laying date and clutch size of the White Stork and identify the cause of seasonal decline in the number of eggs laid. Methods During 1991 and 1996 we recorded clutch size and laying date of pairs breeding next to rubbish dumps (food abundant and constant throughout the breeding season) and birds breeding far from rubbish dumps (using natural food sources). Results In 1991 there was no difference in mean laying date between pairs nesting at rubbish dumps and control pairs. Clutch size was significantly larger at rubbish dump nests. In contrast, mean laying date was earlier in control pairs in 1996 and there was no significant differences in clutch sizes, even when controlling for laying date effect. Conclusion The results support the hypothesis that food availability independently affects both laying date and clutch size. The seasonal decline in clutch size close to rubbish dumps was negligible (1991) or much smaller than in the control zone (1996) suggesting that a progressive deterioration of natural food sources is the most probable reason for a decline in clutch size as the season advances. 相似文献
7.
Capsule Accessing extra food from waste dumps increases egg volume and hatching mass in White Storks. Aim To test how White Storks vary their investment in egg size, especially in last laid eggs, in relation to food availability, and to improve our understanding of the importance of extra feeding on intra-clutch variation. Methods The study was carried out in three White Stork breeding colonies in northern Algeria. Breeding performance was recorded in 70 nests over three years. White Stork colonies situated close to chicken farms were considered to be part of a ‘pseudo experiment’ where parents had access to extra food. Egg volume, laying order, hatching order and hatching weight were recorded. Results Egg volume and hatching mass in White Storks was significantly greater when they had access to extra food. The reproductive value of last laid eggs (fourth and fifth) doubled when females had access to extra food. Conclusion Laying smaller last eggs within a clutch provides a mechanism to facilitate early brood reduction in the White Stork, and so should be advantageous when food is scarce. On the contrary, when females had access to extra food, last laid eggs were as big as first eggs which suggests egg size variation is adaptable to local conditions. 相似文献
8.
The White Stork ( Ciconia ciconia) has an extensive European breeding distribution. There have been significant demographic changes since the 1930s, with country-specific extinctions throughout the western distribution since the mid-1940s. Following various reintroduction programs significant concerns have been raised about the geographic origins of introduced storks, and the effect this may have on individual biology, particularly breeding success. Here we report on seven new microsatellite markers developed for C. ciconia that have been successfully combined in a series of multiplex PCR’s with six markers previously described for the Wood Stork. 相似文献
10.
From 1998 through to 2000, we satellite-tracked the movements of 13 Oriental White Storks ( Ciconia boyciana) on their autumnal migration in order to identify their important stopover sites for preserving links from the Russian Far East breeding sites to the wintering sites in south-eastern China. New analytical methods of satellite tracking data were employed to derive robust information on the locations of stay sites, the number of stopovers made during migration, and the distance traveled without making stopovers. Based on the derived information, we modeled a stay site network as an abstraction of the storks potential migration routes from their breeding sites to wintering sites. Using network analysis techniques, we explored how the loss of stopover sites could affect the connectivity of potential migration routes. The results suggested that if the seashore stopover sites facing Bohai Bay in eastern China were lost, the storks wintering sites along the Yangtze River in south-eastern China would be isolated. Among the seashore stopover sites, Jiantuozhi Gley Mire (39.185°N, 118.627°E), located on the northern seashore of Bohai Bay, was considered particularly important for migrating storks, because it was used every year by the storks we tracked. If conservation needs of this critically located site fail to be addressed, the stay site network of storks can create weak links in the chain of migration and, if broken, storks will have great difficulties in completing their autumnal migration. 相似文献
11.
Summary Here we present a systematic application of magnetic resonance imaging (in the following called MRI) and magnetic resonance spectroscopy (MRS) to the White Stork. The main aim was to demonstrate the annual cycle of fat deposition in the same individuals for comparison to wild conspecifics, to clarify the energy metabolism of this migratory species. To obtain sharp, high-contrast images of the interior of the body, the birds were kept still by enclosing them in simple plastic tubes with additional fixation of legs and head, avoiding the problematic sedation with drugs. Altogether 12 test birds (young storks) were monitored systematically for 15 months, to follow seasonal changes in the internal organs (mainly breast muscles) and tissues (mainly fat depots). At each examination 22 high-contrast pixel images representing serial dorsoventral sections through the body were generated with the computer program MatLab, after which the pixels per section image were converted to tissue components in cm 2 and the distances between consecutive sections used to calculate the tissue volumes in cm 3. To measure the fat in the breast muscle spectroscopy was used to determine the fat : water ratio, from which changes in fat content could be derived. The study revealed pronounced seasonal changes in the visceral and cutaneous/subcutaneous fat depots, which precisely paralleled the annual variation in body weight of the birds (see also the preceding paper, Berthold et al. 2001). The breast muscles exhibited the prolonged growth typical of the juveniles of large species but no conspicuous change at the migration periods. In this project MRI and MRS proved to be successful methods that show great promise.
Magnet-Resonanz-Tomographie und -Spektroskopie der jahreszeitlichen Muster der Körperzusammensetzung: Eine methodische Pilotstudie am Weißstorch (Ciconia ciconia) Zusammenfassung In der vorliegenden Arbeit stellen wir eine systematische Anwendung der Magnet-Resonanz-Tomographie (Kernspin-Tomographie, im Folgenden MRT) und der Magnet-Resonanz-Spektroskopie (im Folgenden MRS) am Weißstorch vor. Hauptaufgabe war es, die Jahresperiodik der Fettdeposition an denselben Individuen zu ermitteln, um Aufschluss über den Energiehaushalt dieser Zugvogelart durch Vergleiche mit freilebenden Vögeln zu bekommen. Die erforderliche Ruhigstellung der Vögel zum Erreichen scharfer kontrastreicher Bilder des Körperinneren war in einfachen Plastikröhren mit zusätzlicher Fixierung von Beinen und Kopf möglich, so dass auf die problematische Sedierung mit Narkotika verzichtet werden konnte. Insgesamt 12 Versuchsvögel (Jungstörche) wurden 15 Monate lang systematisch auf jahresperiodische Veränderungen von inneren Organen (v. a. Brustmuskeln) und Geweben (v. a. Fettdepots) untersucht. Aus je 22 seriellen kontrastreichen dorsoventralen Schnittbildern durch den Vogelkörper ließen sich mit dem Computerprogramm MatLab Pixelbilder erstellen und dann die Pixel pro Schnittbild in Gewebeanteile in cm2 umrechnen und anschließend aus den aufeinander folgenden Schnittbildern die Gewebevolumina in cm3 ermitteln. Für die Fettbestimmung im Brustmuskel wurde durch Spektroskopie das Verhältnis von Fett: Wasser bestimmt, aus dem Veränderungen des Fettgehalts abgeleitet wurden. Die Studie ergab ausgeprägte jahresperiodische Änderungen der viszeralen und kutanen/subkutanen Fettdepots, die genau parallel zum Jahresgang des Körpergewichts der Vögel verliefen (s. auch die vorangehende Arbeit, Berthold et al. 2001). Für die Brustmuskeln ergab sich ein für Jungvögel großer Arten typisches lang anhaltendes Wachstum, aber keine auffallende Veränderung zu den Zugperioden. MRT und MRS erwiesen sich in dieser Arbeit als erfolgreich und vielversprechend. 相似文献
12.
Five new locality records for Artemia in Algeria are given. Some physical and chemical characteristics of their environment are recorded. Predation on Artemia by the fish Aphanius fasciatus occurs where the river Khrouf debouches in Chott Merouan but not elsewhere. 相似文献
13.
The relation between wind, latitude and daily migration speed along the entire migration route of white storks was analysed. Mean daily migration speed was calculated using satellite telemetry data for autumn and spring migration of white storks from their breeding grounds in Germany and Poland to wintering grounds in Africa and back. The National Center for Environmental Prediction (NCEP) reanalysis data were used to systematically fit 850 mb wind vectors to daily migration speed along the migration route. White storks migrated significantly faster and had a shorter migration season in autumn (10 km/h) compared to spring (6.4 km/h). In autumn mean daily migration speed was significantly slower in Europe (8.0 km/h) than in the Middle East (11.1 km/h) and Africa (11.0 km/h). In spring mean daily migration speed was significantly faster in Africa (10.5 km/h) as birds left their wintering grounds than in the Middle East (4.3 km/h). Migration speed then increased in Europe (6.5 km/h) as birds approached their breeding grounds. In both spring and autumn tailwind (at 850mb) and latitude were found to be significant variables related to daily migration speed. 相似文献
14.
黑鹳Ciconia nigra是世界濒危鸟类之一,在我国数量稀少,被列为国家I级保护物种.我们通过监测尕海-则岔国家级自然保护区黑鹳活动情况(2005~2007),发现其具有明显的年活动节律和日活动节律.黑鹳的数量在该保护区呈逐年上升的趋势.另外,也对我国近几年黑鹳记录情况进行了总结,发现2007年所记录的最大数量是中国发现的最大黑鹳群体. 相似文献
15.
Adjakpa, J.B. 2000. The breeding biology of Abdim's Stork Ciconia abdimii in the far north of Benin. Ostrich 71 (1 & 2): 61–63. Little is known about the biology of Abdim's Stork Ciconia abdimii, in Benin. I studied the nesting of this intra- African migrant in the wet season of 1996. Breeding pairs arrived at the end of March 1996. Seven nest sites were found, involving 92 pairs; the largest colony was of 51 pairs. The storks used five different large tree species for nesting. Egg-laying began in early April and lasted until 2 July. Most clutches were of 3–4 eggs. Incubation lasted 28–29 days. A total of 196 young storks fledged (all of which were ringed), representing a success rate of 76.5% per egg laid and 86.0% per egg hatched. The last storks left the colonies on 9 September 1996, 164 days after the first ones arrived on 30 March. The species is threatened in Benin by human persecution and by widespread pesticide use: it urgently requires official protected status. 相似文献
16.
We intended to describe a case of chaunocephalosis and morphological characteristics of its causative agent, Chaunocephalus ferox, recovered from an oriental white stork, Ciconia boyciana, in the Republic of Korea. An oriental white stork was referred to the Wildlife Center of Chungbuk in Korea in February 2014 for severe depression with cachexia and it died the next day. At necropsy, the stomach was severely expanded and 7 thick-walled nodules were observed in the upper part of the intestine. Although the stomach was filled with full of foreign materials, the intestine was almost empty. The nodules were globular and total 9 flukes were recovered. They were 8,030–8,091 μm in length and 3,318–3,333 μm in maximum width. Because the flukes had bulbous forebody with short narrow subcylindrical hindbody, 27 collar spines, and vitelline follicles not reaching to the posterior end, the specimens were identified as being C. ferox. The cyst formation induced thickening of the intestinal wall with narrowing of the lumen that could have contributed to the gastric impaction to the death of the host. This is the first described case of chaunocephalosis and its causative agent C. ferox found from an oriental white stork in Korea. 相似文献
17.
Annual variations in moult, body mass, and the plasma concentrations of luteinizing hormone, prolactin and the gonadal steroids, oestradiol and testosterone, were measured in captive White storks ( Ciconia ciconia ). Data were collected at approximately monthly intervals for 13 months on storks hatched over five successive years, the youngest ones being in their first, the oldest in their fifth, year of life. Moulting of wing feathers occurred during the summer months, April through August. Young birds began to moult at least one month earlier, and replaced more wing feathers each year, than did three- to five-year-old birds. Body mass exhibited remarkably consistent annual cycles with minima of2–9-3-5 kg, during the summer months, and maxima of3–8-4-5 kg, during the winter months. Young males were heavier at all times of the year than young females, although this difference was gradually reduced to non-significant levels by four years of age. Luteinizing hormone, prolactin and the gonadal steroids, oestradiol and testosterone, exhibited annual cyclic changes, usually of a bi-modal nature. No major differences in hormone profiles, however, were found between any of the age groups. The phenomenon of deferred maturity in the stork does not parallel that of puberty found in many mammals. 相似文献
19.
The Japanese regional population of the Oriental white stork ( Ciconia boyciana) became extinct in 1986. Mitochondrial DNA (mtDNA) D-loop region from 20 mounted specimens preserved at public facilities in Toyooka City, Hyogo Prefecture, Japan and its vicinity (n = 17), the area inhabited by the last of the Japanese population, and samples originating from China (n = 3) which were kept at a zoo was analyzed. After extracting DNA from small pieces of skin from mounted specimens, a 1210-bp region of the mtDNA D-loop region was analyzed. The haplotypes among 11 specimens of storks captured or found dead at Toyooka City just before the population became extinct were completely identical. Four haplotypes observed among the mounted specimens preserved in the vicinity of Toyooka City were differentiated from those of captive storks originating from China and Russia in a previous study. Therefore, the last Japanese population might have been a genetically unique group. However, phylogenetic analysis using the maximum likelihood method showed that haplotypes found in the Japanese regional population were closely related to the Chinese and Russian lineages (sequence difference = 2.1%). One mounted specimen collected in 1935 at Izushi village, in the vicinity of Toyooka City, showed the same haplotype as the captive storks from China, suggesting that genetic flow may have historically occurred between the populations of Japan and the continent. Recently, reintroduction for the Oriental white stork has been planned in Toyooka City. The planning for the recovery of extinct populations should not only involve translocation of species to the range from which it disappeared, but also reconstruction of regional populations while considering the genetic lineage between the extinct and introduced populations. 相似文献
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