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1.
A comparative analysis is performed of the polymorphism of the Pleurotus ostreatus (Fr.) Kumm naturally occurring strains isolated from the natural substrates found in two geographically remote Russian natural preserves, the Central Arboreal Biosphere Tver State Preserve (CABTSP) and the Moscow State University Zvenigorod Biological Station (ZBS, Moscow oblast), and within the city of Moscow. The results of the frequency analysis for the isozyme loci alleles and for the sexual and vegetative incompatibility groups are presented; the genetic structure and the interpopulation relations among 58 P. ostreatus dikaryotic strains are estimated. The natural samples from the Moscow and Tver oblasts are shown to have a high degree of polymorphism with a genetic differentiation of 0.743; in spite of their territorial remoteness, they are, however, actively exchanging genetic material. The natural fungal isolates form two reproductively isolated groups.  相似文献   

2.
Endophytic fungi were found in natural populations of giant fescue (Festuca gigantea (L.) Vill.) and bearded wheatgrass (Elymus caninus (L.) L.) on the territory of S.N. Skadovsky Zvenigorod Biological Station (Moscow oblast). Endophytes were isolated from infected seeds of both grass species. All isolates were identified as Epichloë festucae Leuchtm., Schardl & M.R. Siegel.  相似文献   

3.
These studies were conducted in 1999–2010 on the territory of the Zvenigorod Biological Station of Moscow State University (western Moscow suburbs, 55°44′ N, 36°51′ E). Birds (Parus ater) were caught by mist-nets. All the birds were banded and weighed, and their fat reserves were determined; then, the birds were released. A total of 85 individuals were caught. The standard metabolic rate and respiratory quotient (by the method of indirect calorimetry) were measured in 46 experiments with 16 birds. Two peaks were distinguished in the daily locomotor activity: a strongly pronounced daily peak (from 6 a.m. to 4 p.m.) and a weak evening peak (from 6 to 10 p.m.). The body mass did not change during the day. However, some trend for an increase in the mean body mass toward the middle and end of the day was noted. The fat reserves drastically changed during the day. The metabolic rate and respiratory quotient had a well-pronounced diurnal rhythm with minimal values at night (from 12 p.m. to 4 a.m.) and maximum values in the afternoon (from 12 a.m. to 4 p.m.). The total energy budget of Parus ater in the autumn-winter period, energy balance, and the maintenance of constant flying weight along with the dynamics of fat reserves are discussed.  相似文献   

4.
A comparative analysis was performed of the polymorphism of the oyster mushroom Pleurotus ostreatus (Fr.) Kumm naturally occurring strains isolated from the natural substrates from two geographically remote Russian natural preserves, the Central Forest Biosphere Tver State Preserve and the Moscow State University Zvenigorod Biological Station (Moscow oblast), and within the city of Moscow. The results of the frequency analysis for the allozyme loci alleles and for the sexual and somatic incompatibility groups are presented; the genetic structure and the interpopulation relations among 58 Pleurotus ostreatus dikaryotic strains are estimated. The natural samples from the Moscow and Tver oblasts are shown to have a high degree of polymorphism with a genetic differentiation of 0.743; in spite of their territorial remoteness, they are, however, actively exchanging genetic material. The natural fungal isolates form two reproductively isolated groups.__________Translated from Mikrobiologiya, Vol. 74, No. 2, 2005, pp. 231–238.Original Russian Text Copyright © 2005 by Shtaer, Yu. Belokon, M. Belokon, Shnyreva.  相似文献   

5.
Annual breeding productivity of Knots Calidris canutus was estimated by the proportion of first-year birds in winter ringing samples. Significant associations were found between the productivity of Knots, other species that are known to breed on the Taimyr Peninsula, and lemming abundance in that region. It is inferred from this that Knots wintering in southern Africa are of the Russian subspecies canutus unlike British wintering birds which do not show these correlations and are subspecies islandica.  相似文献   

6.
Long-distance migrants have evolved complex strategies for the timing of their annual moult, fattening and migration cycles. These strategies are likely to vary at different stages of a bird's life. Ringing data on 6079 Grey Plovers Pluvialis squatarola , caught on the Wash, England, between 1959 and 1996, were analysed to relate migratory strategies to patterns of primary moult and body mass changes. Adults returning from breeding grounds had a shorter and delayed primary moult (duration 90 days, starting date 19 August) in comparison with over-summering birds (duration 109 days, starting date 5 June). Three categories of migrant adults were identified on the basis of primary moult and body mass: (1) birds which did not moult, but increased body mass and migrated further south; (2) birds which moulted 1–3 inner primaries, suspended moult, increased body mass and migrated; and (3) birds which completed or suspended moult and wintered locally. In birds of the second category, timing of primary moult and body mass increase overlapped. Among wintering birds, 38% were in suspended moult. Ninety-six per cent of birds that suspended moult at the beginning of winter were males and almost all completed moult in spring. Grey Plovers which left Britain in autumn had an average body mass of 280 g, enough to reach southern Morocco without refuelling. Both wintering adults and first-year birds showed a prewinter body mass increase, peaking in December. Adults had a synchronized premigratory body mass increase in May, which suggested a negligible presence of African migrants. The average departure mass for spring migration, estimated at 316 g, would allow birds to fly non-stop to the Siberian breeding grounds in western Taymyr.  相似文献   

7.
Abstract: Migratory birds wintering at the same location are usually coming from populations of different origins, in variable proportions. Using data from individuals banded on their wintering grounds and recovered on their breeding areas, we show that such proportions are estimable given that 1) all breeding populations are identified, and 2) the wintering population can be stratified into ≥1 more site than the number of breeding populations. We applied this technique to woodcock (Scolopax rusticola) banded while wintering in France (N = 35,000) and recovered in other European countries (N = 520). We estimated that the proportion of eastern woodcock among those wintering in France varied spatially, ranging from 70% in northwest France to nearly 100% in southeast France, and increased substantially over the last 15 years. Overall, the method appears powerful to quantify spatial variation of the composition of a population receiving individuals from various origins.  相似文献   

8.
The fauna of chewing lice (Insecta: Phthiraptera) from migratory birds was studied in 2008–2009 and 2017 on the Curonian Spit, at Rybachy Biological Station of the Zoological Institute, Russian Academy of Sciences. Altogether, 35 species of chewing lice were collected off 2010 birds of 65 species. An annotated list of species is presented, including 11 species new to the Russian Federation, 29 species new to the Northwest of Russia, and 2 new host records: Menacanthus eurysternus from Carduellis carduellis and Ricinus frenatusfromCarduellis spinus.  相似文献   

9.
Ron W. Summers 《Ostrich》2013,84(2):167-173
Summers, R. W. 1994. The migration patterns of the Purple Sandpiper Calidris maritima. Ostrich 65: 167–173.

The Purple Sandpiper breeds largely in the Arctic, and winters (boreal season) on the rocky shores of the north Atlantic, further north than any other sandpiper. As the populations from Canada, Greenland, Iceland, Svalbard, Norway and Russia differ in wing and bill lengths it is possible to match measurements taken from breeding birds with samples of birds caught in winter. Ringing recoveries, especially from colour marked birds, have also helped to determine migration routes and wintering areas. Four populations move to the nearest ice-free coast. Two populations move south of the nearest ice-free coast, being replaced by larger birds from a more northerly population (“chain migration”). Only the north Canadian population is believed to migrate a long distance, “leap-frogging” other winter populations. These patterns are discussed in relation to theories for the migration patterns of waders.  相似文献   

10.
Dunlin Calidris alpina is one of the most abundant shorebirds using coastal habitats in the East Atlantic migratory flyway, that links arctic breeding locations (Greenland to Siberia) with wintering grounds (West Europe to West Africa). Differential migration and winter segregation between populations have been indicated by morphometrics and ringing recoveries. Here, we analyse the potential of genetic markers (mitochondrial DNA – mtDNA) to validate and enhance such findings. We compared mtDNA haplotypes frequencies at different wintering sites (from north-west Europe to West Africa). All birds from West Africa had western (European) haplotypes, while the eastern (Siberian) haplotypes were only present in European winter samples, reaching higher frequencies further north in Europe. Compilation of published results from migrating birds also confirmed these differences, with the sole presence of European haplotypes in Iberia and West Africa and increasingly higher frequencies of Siberian haplotypes from south-west to north-west Europe. Comparison with published haplotype frequencies of breeding populations shows that birds from Greenland, Iceland, and North Europe were predominant in wintering grounds in West Africa, while populations wintering in West Europe originated from more eastern breeding grounds (e.g. North Russia). These results show that genetic markers can be used to enhance the integrative monitoring of wintering and breeding populations, by providing biogeographical evidence that validate the winter segregation of breeding populations.  相似文献   

11.
Population dynamics of the White Stork Ciconia ciconia in western France   总被引:3,自引:1,他引: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   

12.
There is an overdue and urgent need to establish patterns of migratory connectivity linking breeding grounds, stopover sites, and wintering grounds of migratory birds. Such information allows more effective application of conservation efforts by applying focused actions along movement trajectories at the population level. Stable isotope methods, especially those using stable hydrogen isotope abundance in feathers (δ2Hf) combined with Bayesian assignment techniques incorporating prior information such as relative abundance of breeding birds, now provide a fast and reliable means of establishing migratory connectivity, especially for Neotropical migrants that breed in North America and molt prior to fall migration. Here we demonstrate how opportunistic sampling of feathers of 30 species of wintering birds in Cuba, Venezuela, Guatemala, Puerto Rico, and Mexico, regions that have typically been poorly sampled for estimating migratory connectivity, can be assigned to breeding areas in North America through both advanced spatial assignment to probability surfaces and through simpler map lookup approaches. Incorporating relative abundance information from the North American Breeding Bird Survey in our Bayesian assignment models generally resulted in a reduction in potential assignment areas on breeding grounds. However, additional tools to constrain longitude such as DNA markers or other isotopes would be desirable for establishing breeding or molt origins of species with broad longitudinal distributions. The isotope approach could act as a rapid means of establishing basic patterns of migratory connectivity across numerous species and populations. We propose a large‐scale coordinated sampling effort on the wintering grounds to establish an isotopic atlas of migratory connectivity for North American Neotropical migrants and suggest that isotopic variance be considered as a valuable metric to quantify migratory connectivity. This initiative could then act as a strategic template to guide further efforts involving stable isotopes, light‐sensitive geolocators, and other technologies.  相似文献   

13.
Abstract The Beringia region of the Arctic contains 2 colonies of lesser snow geese (Chen caerulescens caerulescens) breeding on Wrangel Island, Russia, and Banks Island, Canada, and wintering in North America. The Wrangel Island population is composed of 2 subpopulations from a sympatric breeding colony but separate wintering areas, whereas the Banks Island population shares a sympatric wintering area in California, USA, with one of the Wrangel Island subpopulations. The Wrangel Island colony represents the last major snow goose population in Russia and has fluctuated considerably since 1970, whereas the Banks Island population has more than doubled. The reasons for these changes are unclear, but hypotheses include independent population demographics (survival and recruitment) and immigration and emigration among breeding or wintering populations. These demographic and movement patterns have important ecological and management implications for understanding goose population structure, harvest of admixed populations, and gene flow among populations with separate breeding or wintering areas. From 1993 to 1996, we neckbanded molting birds at their breeding colonies and resighted birds on the wintering grounds. We used multistate mark-recapture models to evaluate apparent survival rates, resighting rates, winter fidelity, and potential exchange among these populations. We also compared the utility of face stain in Wrangel Island breeding geese as a predictor of their wintering area. Our results showed similar apparent survival rates between subpopulations of Wrangel Island snow geese and lower apparent survival, but higher emigration, for the Banks Island birds. Males had lower apparent survival than females, most likely due to differences in neckband loss. Transition between wintering areas was low (<3%), with equal movement between northern and southern wintering areas for Wrangel Island birds and little evidence of exchange between the Banks and northern Wrangel Island populations. Face staining was an unreliable indicator of wintering area. Our findings suggest that northern and southern Wrangel Island subpopulations should be considered a metapopulation in better understanding and managing Pacific Flyway lesser snow geese. Yet the absence of a strong population connection between Banks Island and Wrangel Island geese suggests that these breeding colonies can be managed as separate but overlapping populations. Additionally, winter population fidelity may be more important in lesser snow geese than in other species, and both breeding and wintering areas are important components of population management for sympatric wintering populations.  相似文献   

14.
In migratory birds, the place and time of pair formation are important parameters for population structure and dynamics. Geese are not only migratory but also exhibit long-term monogamy, and therefore the first pairing event in a bird's lifetime is of particular importance. Through behavioural observations of young, known-age, marked birds conducted on the wintering grounds during three winter seasons we investigated two aspects of the timing of first pair formation in the Wrangel Island population of Snow Geese Anser caerulescens : (1) the age at which birds first form pair bonds, and (2) the seasonal pattern of first pair formation. Wrangel Island Snow Geese paired considerably later in life than Snow Geese from a low-Arctic population: almost none of the birds formed pairs in their second winter, and many were still in sibling groups for at least part of that season. The proportion of birds in pairs continued to increase until at least 5 years of age. Most pairing took place during the observation periods, and in general the proportion of birds in pair bonds increased gradually throughout the winter season. The amount of pairing during spring migration or summer varied annually and among cohorts, indicating that even very young birds may be able to form pair bonds quickly if conditions on the breeding grounds are unusually favourable. Pairing later and remaining in family groups longer may be a response to breeding conditions in this high-Arctic colony. Here, productivity is typically low due to harsh weather and predation, whereas Snow Geese breeding in the low Arctic are less restricted and form pairs and start to breed when younger. The fact that most, but not all, pairing takes place on the wintering grounds helps explain why a previous study found a certain amount of gene flow between the two Wrangel Island subpopulations with separate wintering grounds.  相似文献   

15.
Genetic variability of yellow potato cyst nematode G. rostochiensis from three Russian populations (Karelia, Vladimir oblast, and Moscow oblast) was investigated using two types of nuclear markers. Using RAPD markers identified with the help of six random primers (P-29, OPA-10, OPT-14, OPA-11, OPB-11, and OPH-20), it was possible to distinguish Karelian population from the group consisting of the populations from two adjacent regions (Moscow oblast and Vladimir oblast). Based on the combined matrix, containing 294 RAPD fragments, dendrogram of genetic differences was constructed, and the indices of genetic divergence and partition (P, H, and G(st)), as well as the gene flow indices N(m) between the nematode samples examined, were calculated. The dendrogram structure, genetic diversity indices, and variations of genetic distances between single individuals in each population from Karelia and Central Russia pointed to genetic isolation and higher genetic diversity of the nematodes from Karelia. Based on polymorphism of rDNA first intergenic spacer ITS1, attribution of all populations examined to the species G. rostochiensis was proved. Small variations of the ITS1 sequence in different geographic populations of nematodes from different regions of the species world range did not allow isolation of separate groups within the species. Possible factors (including interregional transportations of seed potato) affecting nematode population structure in Russia are discussed.  相似文献   

16.
Summary Blackcaps (Sylvia atricapilla) that breed in central Europe have usually migrated to Mediterranean or African wintering grounds. In the past several decades, a portion of this breeding population has started migrating to the British Isles to overwinter and this population has increased dramatically. Several factors, including higher annual survivorship (due to supplemental feeding and reduced migratiry distance), assortative mating, and enhanced reproductive success may be involved in this rapid population growth. As part of an intensive, long-term study of this population, we tested the hypothesis that the differences in photoperiod experienced by British-wintering versus Mediterranean-wintering blackcaps might lead to relatively early vernal (i.e., migratory and/or reproductive) physiological condition in members of the former group. We found that birds exposed to photoperiodic conditions that simulated migration to Britain to overwinter generally initiated vernal migratory activity earlier than birds held under conditions simulating migration to traditional wintering areas in central Spain. This difference, coupled with the shorter migratory distance to the British Isles, leads to significantly earlier estimated arrival dates for blackcaps that winter in Britain compared to central Spain. Bimodality in arrival times suggests that assortative mating on central European breeding grounds might occur between members of the different wintering populations. Males exposed to British-winter photoperiods showed significantly earlier testicular development than males kept under Spanish-winter photoperiods. Early arrival on the breeding grounds, coupled with accelerated reproductive condition, should lead to a relatively early reproductive effort, perhaps increasing average reproductive success. In general, these results support the hypothesis that differences in photoperiod on the wintering grounds may play an important role in the dynamic state of this population.  相似文献   

17.
Most of the known wintering areas of Piping Plovers (Charadrius melodus) are along the Atlantic and Gulf coasts of the United States and into Mexico, and in the Caribbean. However, 1066 threatened/endangered Piping Plovers were recently found wintering in The Bahamas, an area not previously known to be important for the species. Although representing about 27% of the birds counted during the 2011 International Piping Plover Winter Census, the location of their breeding site(s) was unknown. Thus, our objectives were to determine the location(s) of their breeding site(s) using molecular markers and by tracking banded individuals, identify spring and fall staging sites, and examine site fidelity and survival. We captured and color‐banded 57 birds in January and February 2010 in The Bahamas. Blood samples were also collected for genetic evaluation of the likely subspecies wintering in The Bahamas. Band re‐sightings and DNA analysis revealed that at least 95% of the Piping Plovers wintering in The Bahamas originated on the Atlantic coast of the United States and Canada. Re‐sightings of birds banded in The Bahamas spanned the breeding distribution of the species along the Atlantic coast from Newfoundland to North Carolina. Site fidelity to breeding and wintering sites was high (88–100%). Spring and fall staging sites were located along the Atlantic coast of the United States, with marked birds concentrating in the Carolinas. Our estimate of true survival for the marked birds was 0.71 (95% CI: 0.61–0.80). Our results indicate that more than one third of the Piping Plover population that breeds along the Atlantic coast winters in The Bahamas. By determining the importance of The Bahamas to the Atlantic subspecies of Piping Plovers, future conservation efforts for these populations can be better focused on where they are most needed.  相似文献   

18.
Arctic regions are expected to experience pronounced changes in climate during the current century. Large numbers of waterfowl breed in these regions, and any climate induced changes are likely to have consequences for their demographics. Moreover, environmental changes experienced during migration and on the wintering grounds may also have impacts but remain poorly understood.
We investigate the role of climate variation during breeding, migration and wintering, while controlling for possible effects of mammalian predation and density dependence on the reproduction of Svalbard breeding barnacle geese Branta leucopsis using 40 years of observations.
Breeding success was significantly positively correlated with temperature on both the wintering grounds (Scotland) and breeding grounds (Svalbard), but negatively correlated with the number of days of strong cross-winds during the northward migration period. These factors remained significant when controlling for a strong negative effect of population size.
Goose reproduction on Svalbard was also linked to fluctuations in arctic fox Alopex lagopus populations occurring elsewhere in the arctic. This reveals the importance of mammalian predation, which may vary as a non-linear function of conditions within the wider arctic region.
Climate predictions were used to project barnacle goose reproduction and hence the population until 2050. These simulations suggest the population will grow at between 1% and 2.7% per year, in response to increasing temperatures. However, it is harder to predict how changes in other factors, such as reductions in sea ice, may impact on arctic breeding birds.  相似文献   

19.
Population limitation models of migratory birds have sought to include impacts from events across the full annual cycle. Previous work has shown that events occurring in winter result in some individuals transitioning to the breeding grounds earlier or in better physical condition than others, thereby affecting reproductive success (carry‐over effects). However, evidence for carry‐over effects from breeding to wintering grounds has been shown less often. We used feather corticosterone (CORTf) levels of the migratory Louisiana Waterthrush Parkesia motacilla as a measure of the physiological state of birds at the time of moult on the breeding territory to investigate whether carry‐over effects provide linkages across the annual cycle of this stream‐obligate bird. We show that birds arriving on wintering grounds with lower CORTf scores, indicating reduced energetic challenges or stressors at the time of moult, occupied higher quality territories, and that these birds then achieved a better body condition during the overwinter period. Body condition, in turn, was important in determining whether adult birds returned the following winter, with birds in better condition returning at higher rates. Together these data suggest a carry‐over effect from the breeding grounds to the wintering grounds that is further extended with respect to annual return rates. Very few other studies have linked conditions during the previous breeding season with latent effects during the subsequent overwintering period or with annual survival. This study shows that the effects of variation in energetic challenges or stressors can potentially carry over from the natal stream and accumulate over more than one life‐history period before being manifested in reduced survival. This is of particular relevance to models of population limitation in migratory birds.  相似文献   

20.
Events in the life cycle of migrant birds are generally time‐constrained. Moult, together with breeding and migration, is the most energetically demanding annual cycle stages, but it is the only stage that can be scheduled at different times of the year. However, it is still not fully understood what factors determine this scheduling. We compare the timing of primary feather moult in relation to breeding and migration between two populations of Eurasian golden plover Pluvialis apricaria, the continental population breeding in Scandinavia and in N Russia that migrates to the Netherlands and southern Europe, and the Icelandic population that migrates mainly to Ireland and western UK. Moult was studied at the breeding grounds (N Sweden, N Russia, Iceland) and at stopover and wintering sites (S Sweden, the Netherlands). In both populations, primary moult overlapped with incubation and chick rearing, and females started on average 9 d later than males. Icelandic plovers overlapped moult with incubation to a larger extent and stayed in the breeding grounds until primary moult was completed. In contrast, continental birds only moulted the first 5–7 primaries at the breeding grounds and completed moult in stopover and wintering areas, such as S Sweden and the Netherlands. This overlap, although rare in birds, can be understood from an annual cycle perspective. Icelandic plovers presumably need to initiate moult early in the season to be able to complete it at the breeding grounds. The latter is not possible for continental plovers as their breeding season is much shorter due to a harsher climate. Additionally, for this population, moulting all the primaries at the stopover/wintering site is also not possible as too little time would remain to prepare for cold‐spell movements. We conclude that environmental conditions and migration strategy affect the annual scheduling of primary feather moult in the Eurasian golden plover.  相似文献   

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