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1.
Capsule: Bearded Reedlings Panurus biarmicus show consistent nest timing, select old, compacted areas of reed when positioning their nests, and may adjust nest structure in relation to local reed characteristics and temperature.

Aims: To investigate the nest timing, nest site selection and nest structure of a rare and elusive passerine, the Bearded Reedling at the northern limit of this species’ range.

Methods: A sample of Bearded Reedling nests from the Tay Reedbeds in Scotland were located and monitored with regard to the timing of nesting, fate, fine-scale habitat characteristics and nest structure.

Results: First egg dates and brood sizes were consistent between years of the study despite variation in spring temperatures. Bearded Reedlings nested within unmanaged patches of reed, positively selecting deep leaf litters and compacted reed. Attributes of nest structure, namely internal and external diameter, were influenced by nest site characteristics and local temperature.

Conclusion: Despite a limited sample size, the study suggests that reedbed management should ensure adequate areas of old, dry and unmanaged reed are available when aiming to encourage breeding Bearded Reedlings. Additionally, the apparently flexible structure of the nest may assist this species when coping with changeable climatic conditions.  相似文献   


2.
Zusammenfassung Die Spinalflur nestjunger Bartmeisen(Panurus biarmicus) wird etwa rhombenförmig angelegt. Ihre lateralen Federn werden jedoch schwach ausgebildet und erinnern an Plumae; sie werden sehr bald abgeworfen, so daß flügge Vögel eine schmale, bandförmige Rückenflur haben, die seitlich von nackter Haut (auf der manchmal letzte Federchen sitzen) begrenzt wird. Dieser laterale Teil der Spinalflur kann dann makroskopisch von einem Rain nicht unterschieden werden.Vor Beginn der Jugendvollmauser werden in diesem lateralen Rückenflurbereich durch die Haut Federanlagen sichtbar; die Mauser der Rückenflur (und sehr oft die Mauser überhaupt) wird bei 60% der untersuchten Vögel durch gleichzeitig einsetzendes Wachstum dieser Federn eingeleitet. Die Rückenflur der vermauserten Vögel ist wieder rhombisch wie beim Nestling und bleibt dies fortan.Altvögel werfen lange vor Beginn der Mauser die meisten Plumae ab; die Unterdrückung der lateralen Rückenflur bei Jungvögeln ist wohl eine Analogie dazu.Die Mauser der Rückenflur setzt großflächig ein und unterscheidet sich dadurch von der der Schulter- und Unterflur, wo sie reihenweise, von der Flurmitte ausgehend, erfolgt.Die gesamte Mauser der Bartmeise dauert etwa 50–60 Tage.
Summary In Bearded Tits(Panurus biarmicus) which are a few days old, the dorsal feather tract is of rhombic shape. The feathers in the lateral part of this tract are feebly developed and are shed soon after the birds leave the nest. Thus the dorsal tract of these birds is in the form of a narrow stripe, flanked by naked skin on both sides. Before the onset of the complete post-juvenile moult, papillae of feathers begin to be visible again under the skin in this area. In 60% of the investigated birds, the growth of dorsal feathers began here, and in many cases this represented the start of the growth of adult plumage as well. The dorsal tract in adult birds is of rhombic shape again and remains so for the rest of their life.Adult Bearded Tits shed their down long before moult. It can, therefore, be concluded that this and the suppression of dorsolateral feathers in juvenile plumage are analogous phenomena.In the dorsal tract of moulting Bearded Tits, feather growth begins in one to three centers simultaneously, whereas moult in the ventral and shoulder tracts starts with the inner rows and proceeds towards the outer ones.Whole moult lasts about 50–60 days in Bearded Tits.


Herrn Prof. Dr. Rainer Schubert-Soldern zum 70. Geburtstag herzlichst gewidmet.  相似文献   

3.
Cercariae of the trematodeCryptocotyle concavum, which encyst in skin and/or kidney of sticklebacks and gobies, were studied in the Schlei Fjord (western Baltic Sea). Mean incidence of dermal cysts was 48 % inGasterosteus aculeatus and 37 % inPungitius pungitius. No cysts were found in the kidneys of sticklebacks. While 97 % ofPomatoschistus microps had encysted metacercariae in the kidneys, only 2 % had cysts in the skin.Pomatoschistus minutus, however, showed hardly any cyst infestation of either skin or kidney. InP. microps the intensity of infestation by metacercariae was frequently more than 50 cysts; in contrast, sticklebacks rarely exhibited more than 5 dermal cysts. Infested fish were larger than 10 mm in total length, the incidence rate increasing with growth. Parasitic infestation depends on ambient salinity:C. concavum was not found at salinities below 4 . In contrast to the high incidence in fish, the first hosts — the snailsHydrobia stagnalis andH. neglecta — showed remarkably low infection rates (3 to 5 %). The findings reported are related to the distribution ofC. concavum, the mode of life of infested fish, the feeding habits of the final hosts and the infestation ofP. microps by other parasites. Evidently,P. microps represents an optimal second host forC. concavum.  相似文献   

4.
The Yunnan red‐backed vole Eothenomys miletus (Rodentia: Cricetidae) is an endemic rodent species and reservoir host of zoonoses in southwest China. Based on a large host sample (2463 voles collected from 39 localities between 2001 and 2013), a general analysis of four categories of ectoparasite (fleas, sucking lice, chigger mites and gamasid mites) on E. miletus across its entire range of distribution was made. This analysis identified a total of 71 895 ectoparasites belonging to 320 species (30 species of flea, 9 of sucking louse, 106 of gamasid mite and 175 of chigger mite) with a high prevalence (87%), mean abundance (29.19) and mean intensity (33.69). Of the 18 vector species of zoonoses found on E. miletus, the flea Ctenophthalmus quadratus (Siphonaptera: Hystrichopsyllidae) and chigger mite Leptotrombidium scutellare (Trombidiformes: Trombiculidae) were the dominant species; these are the main vectors of zoonoses in China. All of the dominant parasite species showed an aggregated distribution pattern. Male voles harboured more species of parasite than females. Chigger mites represented the most abundant species group on voles and their prevalence was positively correlated with mean abundance (r = 0.73; P < 0.05). As a single rodent species, E. miletus has a high potential to harbour abundant ectoparasites with high species diversity and high rates of infestation. The sex of the vole affects ectoparasite infestation.  相似文献   

5.
The ectoparasitic mite, Varroa destructor, shifted host from the eastern honeybee, Apis cerana, to the western honeybee, Apis mellifera. Whereas the original host survives infestations by this parasite, they are lethal to colonies of its new host. Here, we investigated a population of A. cerana naturally infested by the V. destructor Korea haplotype that gave rise to the globally invasive mite lineage. Our aim was to better characterize traits that allow for the survival of the original host to infestations by this particular mite haplotype. A known major trait of resistance is the lack of mite reproduction on worker brood in A. cerana. We show that this trait is neither due to a lack of host attractiveness nor of reproduction initiation by the parasite. However, successful mite reproduction was prevented by abnormal host development. Adult A. cerana workers recognized this state and removed hosts and parasites, which greatly affected the fitness of the parasite. These results confirm and complete previous observations of brood susceptibility to infestation in other honeybee host populations, provide new insights into the coevolution between hosts and parasites in this system, and may contribute to mitigating the large‐scale colony losses of A. mellifera due to V. destructor.  相似文献   

6.
Some avian Harpirhynchidae mites live under the skin and develop cutaneous cysts. Despite the obvious lesions that these parasites can produce, little is currently known about the behavioural disturbances that cyst-forming mites may cause in infected wild birds. We report an infection by Harpirhynchidae mites in a hawfinch (Coccothraustes coccothraustes) in southeast Spain. The bird was easily captured due to its inability to fly. During clinical examination it was found to have multiple severe traumatic injuries, possibly due to a blow or a fall, as result of which the bird was euthanized. At necropsy, the hawfinch was found to be in good body condition. Two yellowish and friable mite-filled cysts were detected in the subalar region of both wings. Mites were morphologically identified as Harpirhynchus nidulans, and histological analysis of the cystic lesions was also performed. This is the first time that the occurrence of a hawfinch infected by H. nidulans in the Iberian Peninsula has been reported.  相似文献   

7.
Summary

The intensity and timing of infestation events of caligid copepods in wild or cultured fish populations may be predicted from previous local production of nauplius I of the parasite. However, this relationship is not well established, the spatial scales over which it operates are unclear, and the role of host reactions to the invading copepodid is unknown. Rate of development (and population structure), generation time and rate and actual reproductive output are temperature-dependent. In Ireland between five and seven generations of Lepeophtheirus salmonis (Krøyer) can develop annually and generation time varies from over 120 days in winter to 23 days in summer. Host reactions may affect the rate of development of the parasite but are less important than temperature. Host reactions may also cause parasite mortality, but this effect is specific for individual host parasite associations. The distribution of L. salmonis in cultured host populations is typically normal but is very over-dispersed in wild populations with heavy infestations. Parasiteinduced morphological damage to the host is correlated with physiological impacts. Physiological effects are present even when morphological damage is slight and so intermittent chemotherapeutic control of infestations cannot prevent some parasite impact from occurring.  相似文献   

8.
Summary It is discussed whether the hybridization theory ofSpitzer (1973) with respect to the Bearded Tit populations of The Netherlands and England has been posed on accurate grounds.Apart from the fact thatSpitzer only examined a small number of English specimens, it has been shown that the so-called hybrid characters fall within the range of variation as described for the nominate race in the 18th and 19th century literature. Four skins of nominatebiarmicus collected ca. 1820 near Brunsbüttel (Holstein, FRG) and two Dutch skins collected in 1852 and 1862 confirmed the conclusion that the distinctionsSpitzer made between hybrid features and characteristics of the nominate race were based on an erroneous interpretation. Furthermore it is shown thatrussicus has no selective advantage at all;biarmicus too, is capable of changing its diet from insects to seeds by adaptation of the gizzard.It is concluded that on the grounds advanced bySpitzer Bearded Tits in The Netherlands and England cannot be considered as hybrids.
Bartmeisen in den Niederlanden und Großbritannien: Bemerkungen zur Hybridisationstheorie
Zusammenfassung Es wird diskutiert, obSpitzers (1973) Hybridisationstheorie für die englisch-holländische Population der Bartmeise Gültigkeit hat. Die von ihm vorgetragenen Argumente werden kritisch geprüft. Abgesehen von der Tatsache, daßSpitzer nur eine kleine Anzahl englischer Bartmeisen untersuchte, konnte gezeigt werden, daß die sogenannten Hybridmerkmale innerhalb der Grenzen der Variationsbreite liegen, die bereits aus der Literatur des 18. und 19. Jh. ersichtlich sind. Vier Exemplare der Nominatform, gesammelt um 1820 bei Brunsbüttel (Holstein), und zwei holländische Stücke von 1852 und 1862 bestätigen die Schlußfolgerung, daßSpitzers Unterschiede zwischen Hybrid- und Nominatmerkmalen auf einer fehlerhaften Interpretation beruhen.Russicus hat keinen Selektionsvorteil, denn auchbiarmicus ist zur Umstellung von Insekten- auf Schilfsamenkost durch Umstrukturierung des Muskelmagens imstande.Spitzers Argumente reichen also nicht aus, um Bartmeisen der englisch-holländischen Population als Hybriden einzustufen.
  相似文献   

9.
ABSTRACT

Capsule: We document previously undescribed nocturnal flight behaviour by Bearded Vultures Gypaetus barbatus using a combination of accelerometer and global positioning system (GPS) information.

Aims: To study the nocturnal flight activity of the Bearded Vulture and determine whether nocturnal flights could be linked to foraging behaviour.

Methods: We used both accelerometer and GPS location data of 11 Bearded Vultures in the Spanish Pyrenees along with 88 carcasses monitored with camera traps.

Results: Over half (55%, n?=?11) of the individuals tracked were recorded flying between 0.7 and 6.1?km on at least 19 different nights, including 37% that occurred when less than 20% of the moon was illuminated. Bearded Vultures displayed feeding activity in only 8.2% of the 146 feeding events existing during the hour after dawn and the hour before dusk.

Conclusions: Our findings suggest that foraging benefits do not explain the nocturnal flights. Disturbances or adverse weather conditions may result in the abandonment of an overnight roosting site. This could also explain why individuals recovered in the field showed impact injuries.  相似文献   

10.
P. Slater 《Bird Study》2013,60(3):361-366
Capsule Between 1981 and 2008 population size was stable, but there were negative trends in breeding parameters.

Aims To determine the current status and long‐term population trend of an isolated breeding population of Bearded Vultures Gypaetus barbatus (Corsica, Mediterranean).

Methods The total Bearded Vulture population was monitored between 1981 and 2008.

Results The current effective breeding population size of Bearded Vultures in Corsica is ten pairs/trios with a slight increase of one to two pairs since 1983. The population is currently estimated at 25 individuals. Breeding parameters (laying rate, breeding success and productivity) have decreased significantly over the full 28‐year study period, although the decrease was not significant when the data set was restricted to 1988–2008. A mean of 60.3% (n = 204) of pairs have laid, but this proportion is highly variable between years. Productivity has been very low (0.16 young/pair/year, n = 233). Breeding parameters of the Corsican population of Bearded Vultures are very low compared with those of other western European populations in the Pyrenees.

Conclusions This isolated insular population is of small size (eight to ten pairs/trios) but shows a stability of distribution and numbers, but low (and decreasing) breeding rates, making this insular population one the most threatened in Europe.  相似文献   

11.
Capsule Re-use is infrequent although birds reproduce equally well in re-used and new holes.

Aims To describe frequency of hole re-use by Marsh Tits in primeval forest with superabundant holes; to examine how depredation, disturbance, ectoparasites or the low quality of previously used holes influenced birds' decision to switch holes; to assess whether Marsh Tits benefited from re-using holes.

Methods Birds were observed living in undisturbed conditions in a strictly protected part of the Bia?owie?a National Park (Poland) during 13 breeding seasons, hole attributes were measured, and observations made of nest fate and bird survival.

Results Marsh Tits re-occupied 35.5% of available holes used the previous year (n = 214). The holes were most often re-used when both birds survived (42%) or when the surviving female was paired to a new male (35%). Holes were re-used less often after brood failure than after successful breeding (13% versus 39%). Other possible factors (ectoparasite infestation, inferior hole quality or a bird being caught at hole) had no effect on the re-occupation frequency. Birds in the retained and new holes bred at the same time, laid the same number of eggs, and had almost identical nesting success (78% versus 76%).

Conclusion Superabundant holes in the primeval forest allow Marsh Tits to change holes frequently. Similar outcomes of breeding in the re-used and new holes indicate that choices made by the birds are largely neutral, i.e. there is no strong selection pressure for or against hole re-use.  相似文献   

12.
The original function of the tail in birds is likely to be related to flight performance or bipedal locomotion. In this study, we examined the role of the long graduated tail of male Bearded Tits Panurus biarmicus , focusing on the function of the tail as a balancing organ when moving in reeds, the habitat in which this species spends its whole life. We performed an aviary experiment using males with shortened, elongated or control (unmanipulated) tails and recorded their use of different reed heights and preferences for different sitting postures. Tail manipulation did not change the use of different reed heights between treatments. The head-up posture was the preferred sitting technique and was independent of tail length. We found that males with elongated tails showed less variation in the use of different sitting postures along the reed. In addition, the use of the 'straddle' sitting technique varied in relation to tail length, tending to be less frequent when tails were experimentally shortened. These results suggest that tail length influences how Bearded Tits move and may exploit their habitat. The role of the tail as a balancing organ when using small twigs or branches may have been underestimated.  相似文献   

13.
Abstract

A new species of feather mite (Acari: Analgidae), Kiwialges haastii n. sp. is described from the great spotted kiwi, Apteryx haastii Potts, 1872. Four new host records are reported and a key to species of Kiwialges is presented.  相似文献   

14.
Ectoparasites have often been shown to have detrimental effects on their host. Not much is known, however, about determinants of infestation, e.g. the question of which factors affect distribution and occurrence of parasites on different host species (degree of host specificity) and their infestation rates. In this study we examine possible effects of host determinants on parasite intensity of Carnus hemapterus (Carnidae), an ectoparasitic fly on nestling birds, in the European bee-eater (Merops apiaster), which is a common host of C. hemapterus. Our results show that European bee-eaters seem to be one of the most heavily infested host species of C. hemapterus. We found that brood size, nestling age, and colony size are the most important determinants of infestation by C. hemapterus. This parasite seems to prefer medium-sized bee-eater chicks and to select them according to their condition. Our results further suggest a negative effect of C. hemapterus on chick development.  相似文献   

15.
Capsule: Blue Tits and Great Tits occupied different habitats within forests in Central Europe but their nestlings shared a similar diet.

Aims: To quantify the differences in offspring diet and territory habitat between Great Tits Parus major and Eurasian Blue Tits Cyanistes caeruleus in two European forests, and to test whether the ecological niches of the two species overlap.

Methods: Research was conducted on Great Tits and Eurasian Blue Tits, breeding in nest boxes in two forests near Kraków, Poland, during years: 2009, 2011 and 2012. Nine days after hatching, food items were collected from offspring using neck-collars. Habitat parameters surrounding each nest box were quantified.

Results: Great Tit territories were in old Oak-Hornbeam forest, whereas Blue Tits often nested in mixed forest. There were no significant differences between the two bird species in the variation in their caterpillar diets for which both species were highly variable. Great Tits collected more caterpillars of Noctuidae per nest than did Blue Tits in 2009 and 2011 in Niepo?omice Forest; Blue Tits collected more Tortricidae in 2011 and more spiders every year. In Krzyszkowice Forest in 2012, tits fed their nestlings in different periods and did not differ in the proportion of caterpillars. Habitat affected diet differently in each species.

Conclusion: Although Great Tits and Blue Tits occupied different territories in each forest and year of research, the diets of both species’ nestlings contained similar species of invertebrates. The overlaps of the birds’ environmental needs are specific at a local scale.  相似文献   

16.
Abstract

Melophagus ovinus (the sheep ked), Damalinia ovis (the sheep biting louse), and, for the first time, Chorioptes bovis (the scrotal mange mite) were found on Campbell Island on feral sheep that had never been shorn or dipped. M. ovinus was present on all animals; infestation levels were independent of the age or sex of the host. More ewes than rams were infested with D. ovis, although 4-tooth and younger rams were more frequently infested than older rams. Louse numbers were higher on older ewes (6-tooth and older) than on younger ewes, but on rams were independent of the age of the host. No other ectoparasites were found.  相似文献   

17.
Recent climate change has affected the phenology of numerous species, and such differential changes may affect host–parasite interactions. Using information on vectors (louseflies, mosquitoes, blackflies) and parasites (tropical fowl mite Ornithonyssus bursa, the lousefly Ornithomyia avicularia, a chewing louse Brueelia sp., two species of feather mites Trouessartia crucifera and Trouessartia appendiculata, and two species of blood parasites Leucozytozoon whitworthi and Haemoproteus prognei) of the barn swallow Hirundo rustica collected during 1971–2008, I analyzed temporal changes in emergence and abundance, relationships with climatic conditions, and changes in the fitness impact of parasites on their hosts. Temperature and rainfall during the summer breeding season of the host increased during the study. The intensity of infestation by mites decreased, but increased for the lousefly during 1982–2008. The prevalence of two species of blood parasites increased during 1988–2008. The timing of first mass emergence of mosquitoes and blackflies advanced. These temporal changes in phenology and abundance of parasites and vectors could be linked to changes in temperature, but less so to changes in precipitation. Parasites had fitness consequences for hosts because intensity of the mite and the chewing louse was significantly associated with delayed breeding of the host, while a greater abundance of feather mites was associated with earlier breeding. Reproductive success of the host decreased with increasing abundance of the chewing louse. The temporal decrease in mite abundance was associated with advanced breeding of the host, while the increase in abundance of the lousefly was associated with earlier breeding. Virulence by the tropical fowl mite decreased with increasing temperature, independent of confounding factors. These findings suggest that climate change affects parasite species differently, hence altering the composition of the parasite community, and that climate change causes changes in the virulence of parasites. Because the changing phenology of different species of parasites had both positive and negative effects on their hosts, and because the abundance of some parasites increased, while that of other decreased, there was no consistent temporal change in host fitness during 1971–2008.  相似文献   

18.
Fifty specimens of Notothenia coriiceps caught in Potter Cove, King George Island, were examined for ecto- and endoparasites. Of the 22 parasite species found, 18 were helminths, 2 were hirudineans and 2 were crustaceans. The isopod Aega antarctica and an unidentified hirudinean are reported for the first time from this fish host. Dominant parasites were the adults of Aspersentis megarhynchus, the invasive stage of Corynosoma spp. (cystacanth) and the adults of Macvicaria pennelli, with respective prevalences of infestation of 94, 76 and 74%. The preferred sites of infestation were the pylorus and intestine, where five different larval (nematodes and cestodes) and eight adult (digeneans and acanthocephalans) parasite species were found. No adult nematodes and cestodes were found and no parasites could be isolated from the musculature. The results of the present study are related to previous findings on the parasite fauna of N. coriiceps. The comparison implies a high parasite diversity in this benthic Antarctic fish species. Most parasites found appear to have a wide range of distribution within Antarctic waters together with a low host specificity. Besides its role as final host for several species of trematodes and acanthocephalans, N. coriiceps serves as transmitter of parasite larvae to piscivorous birds and seals. It is concluded that the parasite fauna in Antarctic fish species provides important insights into the different habitat use and trophic relationship of their fish hosts. Received: 11 September 1997 / Accepted: 12 January 1998  相似文献   

19.
1. A simulation model investigating the co‐evolution of water mites infesting their aquatic insect hosts during emergence is presented. The model is based on field and experimental studies of the ectoparasitic water mite Arrenurus cuspidator and the damselfly Coenagrion puella. 2. Three scenarios were studied: (1) Only the host was allowed to evolve timing of emergence, while the timing of the parasites' infestation opportunity was held constant. (2) Both host and parasite were allowed to evolve. (3) Only the parasite's timing was allowed to evolve, while the host was constrained completely. 3. In the first two scenarios, parasite abundances decreased in the course of evolution and reached values well below those found in the field, whereas in the third scenario, parasite abundances were maintained at a level close to that found in the field. In the second scenario (co‐evolution), the host seemed to be the leader in the evolutionary race. 4. It is concluded that water mite parasitism is capable of shaping emergence patterns in aquatic insects and, despite the same life‐cycle length for host and parasite, the parasite evolves fast enough to shape its hatching pattern to match the emergence pattern of its host.  相似文献   

20.
Capsule Blue Tits sang their dawn song in trees that provided greater concealment.

Aims To determine if dawn singing Blue Tits select trees that increase their concealment.

Methods We compared the timing of leaf growth initiation in Blue Tit song-post trees to the average timing of leaf growth initiation for other tree species within 25 m of the song-post.

Results Most Blue Tits (96%, n = 23) sang from tree species that begin leaf growth earlier than the average tree available within 25 m. If males singing in Hawthorns Crataegus monogyna were excluded, 92% (n = 13) sang from earlier leafing trees.

Conclusion Dawn singing Blue Tits select perches that offer greater concealment.  相似文献   

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