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1.
Effective population size, levels of genetic diversity, gene flow, and genetic structuring were assessed in 205 colonial Roseate spoonbills from 11 breeding colonies from north, central west, and south Brazil. Colonies and regions exhibited similar moderate levels of diversity at five microsatellite loci (mean expected heterozygosity range 0.50–0.62; allelic richness range 3.17–3.21). The central west region had the highest Ne (59). F ST values revealed low but significant genetic structuring among colonies within the north and within the south regions. Significant global genetic structuring was found between the northern and central western populations as well as between the northern and southern populations. An individual-based Bayesian clustering method inferred three population clusters. Assignment tests correctly allocated up to 64% of individuals to their source regions. Collectively, results revealed complex demographic dynamics, with ongoing gene flow on a local scale, but genetic differentiation on a broader scale. Populations in the three regions may all be conserved, but special concern should be given to central western ones, which can significantly contribute to the species’ gene pool in Brazil.  相似文献   

2.
Five breeding colonies of the Roseate spoonbill (Aves: Platalea ajaja) from two Brazilian wetland areas (Pantanal and Taim marshes) were sampled, and domain I of the mitochondrial DNA control region (483 bp) was sequenced in 50 birds. The average haplotype diversity (h = 0.75, s = 0.071) and average nucleotide diversity (pi = 0.004, s = 0.003) were evaluated, and nonsignificant differences were found among the colonies studied. The lack of differentiation among breeding colonies revealed by AMOVA analysis was explained either as a consequence of high gene flow or recent expansion. The significantly negative results of the neutrality tests (Fu's F ( s ) = -23.271, P < 0.01; Tajima's D = -1.941, P < 0.01) associated with the star shape of the haplotype tree and mismatch distribution data are evidence supporting the idea that these populations underwent a recent demographic expansion in the Pantanal region. The average time since the expansion is estimated to be 25,773 years, and this agrees with a period of increased moisture that occurred during the last glacial period.  相似文献   

3.
Some aspects of sperm competition were studied in the white spoonbill (Platalea leucorodia) breeding in Doñana National Park (SW Spain). Shorter pair copulation intervals occurred during the prelaying period, when females were subjected to a relatively high frequency of extra-pair copulations. Pair copulation intervals with an intermediate extra-pair copulation by the male mate were longer than those without extra-pair copulation. This result indicates that males need a time of recovery between copulations before they can perform another. Extra-pair copulations by the females did not affect the length of intervals between pair copulations. There were no differences between the lengths of the intervals between an extra-pair copulation by the female and the following pair copulation for cases in which the male mate detected an intruder male attempting copulation with his mate and those in which the intruder remained undetected. However, the correlations obtained between copulatory intervals for detected and undetected cases suggest a copulatory response by their mates, although affected by the required recovery time between copulations by the males. Finally, since extra-pair copulations mainly occurred while male mates were collecting nest material, they engaged in this activity shortly after pair copulations, probably to avoid a last-male advantage under the sperm competition pressure.  相似文献   

4.
The endangered Black-faced Spoonbill Platalea minor has experienced drastic reductions in population size, geographic distribution, and habitat availability throughout East Asia. In the present study, we examined population genetic structure and genetic diversity of Black-faced Spoonbills inhabiting five sites off the west coast of South Korea encompassing a few of its major breeding sites. Ten microsatellite loci and the mitochondrial sequence were used to assess patterns of genetic variation based on 63 individuals. Three ND2 haplotypes were found among 61 individuals; the remaining two were identified as Eurasian Spoonbills, revealing an unexpected hybridization between these two species having different ecological niches in South Korea—the Eurasian Spoonbill overwinters in inland areas, whereas the Black-faced Spoonbill inhabits coastal areas during the summer. Analyses of microsatellite variation revealed no discrete population structure among the five breeding sites but very weak genetic differentiation among geographically distant regions. Assignment tests identified several possible migrants among sites. Our findings suggested that Black-faced Spoonbills from the five breeding sites could be managed as a single population and highlighted the importance of conserving the populations from Maedo, Suhaam, and Namdong reservoir, which are geographically close and have retained high levels of genetic diversity and large populations.  相似文献   

5.
Decorataria magnilabiata (Molin, 1860) n. comb. is proposed for Dispharagus magnilabiatus Molin, 1860 [= Acuaria (Cheilospirura) magnilabiata (Molin, 1860) Railliet, Henry & Sisoff, 1912; Cheilospirura magnilabiata (Molin, 1860) Stiles & Hassall, 1920; Dispharynx magnilabiata (Molin, 1860) Gendre, 1920] (Nematoda, Spirurida, Acuariidae), a parasite of the roseate spoonbill Platalea ajaja L. (Ciconiiformes, Threskiornithidae) known from Brazil, France (bird in captivity), Argentina and Cuba. The species is redescribed and illustrated on the basis of the type-series (from Brazil) in the Helminthological Collection of the Naturhistorisches Museum, Vienna. Syncuaria diacantha Petter, 1961 [= Decorataria diacantha (P.) Skryabin, Sobolev & Ivashkin, 1965], originally described from Platalea ajaja in France (bird in captivity), is recognised as a junior synonym of Decorataria magnilabiata (new synonymy).  相似文献   

6.
M. P. Kahl 《Ibis》1983,125(3):324-338
Breeding colonies of the African Spoonbill Platalea alba were studied in Kenya and South Africa during 1980. In Kenya nesting was in trees and in South Africa in reedbeds; the nesting area in both colonies was shared with other species of waterbirds.
During the breeding season, adult African Spoonbills acquire a more immaculate plumage and brighter soft-part coloration. Sexes are distinguishable by the larger size and more robust proportions of males.
Males are more sedentary and aggressive during pair formation, and females are more mobile and submissive. The general pattern of pair formation is described, with a variety of ritualized courtship displays acting to bring and keep the sexes together.
Comfort movements, vocalizations, and 14 distinct ritualized social displays are described and illustrated for the African Spoonbill. Some similarities and possible homologies with displays of other ciconiiform birds are mentioned. This paper represents the first part of a continuing study of the comparative ethology of the five species of spoonbills of the world.  相似文献   

7.
白琵鹭雏鸟的生长和恒温能力的发育   总被引:1,自引:0,他引:1  
1994年和 1995年 4~ 6月在扎龙自然保护区 (4 7°2 9′N ,12 4°0 2′E)测定了 13只白琵鹭 (Platalealeucorodia)雏鸟的体重、体长、翅长、跗长和体温 ,以及环境温度。雏鸟生长符合逻辑斯谛模型 ,而 4~ 8日龄相对生长率最大。随着雏鸟日龄增大 ,体温稳步增加而且不随环境温度局部波动改变 ;冷暴露 2 5min后体温下降的幅度减小。孵出至 2 8日 ,雏鸟的体重与在巢内和冷暴露后的体温正相关 ,其体重和体长也与恒温指数正相关 ,雏鸟身体生长和恒温能力发育有某种同步关系 ,体现了晚成鸟的发育特点。  相似文献   

8.
1999年6月15日在中国黄海北部辽宁省大连市长海县石城乡一个无人居住的岛屿上,首次发现了3对黑脸琵鹭的繁殖个体(在观察时还见到另外3只黑脸琵鹭)。该岛屿位于石城乡东侧,北纬39°31′,东经123°02′,面积约025km2,海拔高46m。鸟的群落结构主要以黑尾鸥数量最多,约有800只左右,其次为黄嘴白鹭约400只左右,还有少量的银鸥、海鸥等在岛上繁殖。  相似文献   

9.
Grzegorz Kopij 《Ostrich》2013,84(2-4):77-79
Kopij, G. 1997. Breeding ecology of the African Spoonbill Platalea alba in the Free State, South Africa. Ostrich 68 (2–4): 77–79.

The breeding ecology of the African Spoonbill is surprisingly little known. In the Free State, the number of nesting African Spoonbills appears to have declined; 120 nests in 11 colonies were located in 1972–1973, compared to 32 nests in four colonies in 1993–1996 (though this later survey may have missed a few small colonies). In 1976–1977, a colony with 15 active spoonbill nests was monitored for an entire breeding season. Mean clutch size was 2.6 (n = 15); 56% of eggs hatched; 91% of hatched eggs resulted in fledglings; and chicks fledged from 53% of nests. The main food of spoonbill chicks was frogs, mainly Rana angolensis and Xenopus laevis, and aquatic invertebrates.  相似文献   

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14.
A total of 123 nests of the Cinereous Vulture, Aegypius monachus, was found in three different nesting areas in Middle Sakarya Region, Western Turkey, during three years. The number of breeding pairs was 32 in 2010, 46 in 2011 and 42 in 2012. This is the largest Cinereous Vulture colony in Turkey and the most important breeding area in the western part of its distribution outside Spain. Breeding success was 0.78 fledgling per occupied nest in 2010, 0.73 in 2011 and 0.54 in 2012. The most unsuccessful breeding occurred mostly between May and July, when recreational activities and various economic human activities increased in the area.  相似文献   

15.
Canine herpesvirus-1 (CHV-1) is presumed to be enzootic in the dog population and is associated with reproductive disorders and neonatal mortality. To advise dog breeders towards an effective management of CHV-1 infected colonies, 27 breeding bitches were studied during one reproductive cycle in field conditions: the effect of cycle stage, kennel size, initial antibody titre, mating and gestation on serologic and viral excretion patterns was evaluated, while the association between reproductive disorders and CHV-1 antibody titres and viral excretion was also analysed. All initially seronegative bitches seroconverted, while 40% of the initially seropositive bitches became seronegative at one or two occasions. No difference in antibody patterns was observed between mated and unmated bitches. Of the mated bitches, 46% experienced infertility, foetal resorption or mummification. No difference in antibody patterns was observed depending on the occurrence of reproductive disorders even if a decrease in antibody titres during early or late-di-oestrus was often present. Significantly higher titres were observed at all cycle stages in large kennels. None of the vaginal and nasal samples or buffy coats tested positive for CHV-1 DNA. The mixed image of clinical and sub-clinical carriage in this study demonstrated CHV-1 has a complex and difficult to predict clinical behavior. Preventive management with vaccination of reproducing bitches in kennels with reproductive disorders should therefore be advised.  相似文献   

16.
The productivity of breeding colonies of Mongolian gerbils can be substantially enhanced by using as breeding stock only the 40% of females that exhibit vaginal opening before reaching 25 days of age. Early-maturing females are more likely to breed successfully on first pairing. The lifetime fecundity of early-maturing females is more than twice that of their late-maturing sisters. In those cases in which early-maturing females fail to breed with the first male with which they are paired, they (but not late-maturing females) can be mated with a second male with a high probability of success. Two-thirds of the early-maturing females that failed to reproduce following a first pairing became pregnant following a second. Only 11% of late-maturing females did so.  相似文献   

17.
Determining the genetic structure of tropical bird populations is important for assessing potential genetic effects of future habitat fragmentation and for testing hypotheses about evolutionary mechanisms promoting diversification. Here we used 10 microsatellite DNA loci to describe levels of genetic differentiation for five populations of the lek-mating blue manakin (Chiroxiphia caudata), sampled along a 414-km transect within the largest remaining continuous tract of the highly endangered Atlantic Forest habitat in southeast Brazil. We found small but significant levels of differentiation between most populations. F(ST) values varied from 0.0 to 0.023 (overall F(ST)=0.012) that conformed to a strong isolation by distance relationship, suggesting that observed levels of differentiation are a result of migration-drift equilibrium. N(e)m values estimated using a coalescent-based method were small (相似文献   

18.
Strange visitors to the pied flycatcher nest-boxes during the brood-rearing period were investigated in the Moscow oblast during 15 seasons. The total amount of visits was 760. Most of the visits (94%) were made by males and 5% and 1% were made by females and young birds with juvenile plumage, respectively. Both bachelor and paired males of various ages were among the visitors. Most of the adult birds and all young ones behaved as ??inspectors??; a part of the visitors tried to feed nestlings. Among them, only nine males and a female were constant ??helpers.??  相似文献   

19.
Euterpe edulis (Arecaceae) Mart has high ecological and economic importance providing food resources for more than 58 species of birds and 20 species of mammals, including humans. E. edulis is the second most exploited nontimber product from Brazilian Atlantic Forest. Due to overexploitation and destruction of habitats, E. edulis is threatened by extinction. Euterpe edulis populations have large morphological variations, with individuals having green, red, or yellow leaf sheath. However, no study has related phenotypic distinctions between populations and their levels of genetic structure. Thus, this study aimed to evaluate the diversity and genetic structure of different E. edulis morphotypes. We sampled 250 adult individuals in eight populations with the different morphotypes. Using 14 microsatellite markers, we access genetic diversity through population genetic parameters calculated in the GenAlex program and the diveRsity package in R. We used the Wilcoxon test to verify population bottlenecks and the genetic distance of Nei and Bayesian analysis for genetic clusters. The eight populations showed low allele richness, low observed heterozygosity, and high inbreeding values (f). In addition, six of the eight populations experienced genetic bottlenecks, which would partly explain the low genetic diversity in populations. Cluster analysis identified two clusters (K = 2), with green morphotype genetically distinguishing from yellow and red morphotypes. Thus, we show, for the first time, a strong genetic structure among E. edulis morphotypes even for geographically close populations.  相似文献   

20.
Large areas with hydrocarbon prospects offshore northwest Greenland necessitate seabird studies in this region. The little auk population breeding in Thule District is the largest seabird population in northwest Greenland, as well as the largest known population of this species. In 1994 and 1995 we mapped the distribution of little auk colonies in Thule District during aerial surveys. Most colonies are situated in sloping screes facing the sea, some as far as 11 km from the coast in valleys or facing glaciers. The total horizontal extent of the colonies is about 400 km. Our surveys generally confirm previous and local knowledge, although the information obtained is more detailed. Received: 11 November 1996 / Accepted: 21 September 1997  相似文献   

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