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1.

001-es BibID:BIBFORM022540
Első szerző:Pap Péter László (ökológus)
Cím:Frequency and consequences of feather holes in Barn Swallows Hirundo rustica / Péter László Pap, Jácint Tökölyi, Tibor Szép
Dátum:2005
ISSN:0019-1019
Megjegyzések:The relationship between feather quality, estimated through the prevalence and intensity of feather holes, and the breeding performance and survival of the Barn Swallow Hirundo rustica was studied over a 5-year period. In addition, we present some indirect data on the role of chewing lice in producing the feather holes. The balanced distribution of feather holes (high prevalence, low aggregation) corresponds with the pattern of distribution of lice on colonial birds, and in the Barn Swallow. Feather holes were significantly and positively associated with the arrival dates of the birds, as both males and females with an increased number of feather holes started laying later. Females that survived the winter had significantly fewer holes than non-surviving females, whereas there was no difference in feather hole number between surviving and non-surviving males. Given that there was no association between the number of feather holes and body condition indices, except for the tail length of male Barn Swallows, we suggest that the negative effect of feather holes on the fitness of the birds is mainly apparent during periods of intensive locomotor activity, such as migration. Alternatively, if feather holes are an indicator of quality, those birds with a high intensity of feather holes may have been of poor quality. These birds may have been less able to cope with the environmental conditions, resulting in the lower survival and later arrival of the birds to the breeding grounds. The negative relationship between the length of the outermost tail feathers of males and the incidence of feather holes suggests that the tail is a condition-dependent secondary sexual characteristic.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:The Ibis. - 147 : 1 (2005), p. 169-175. -
További szerzők:Tökölyi Jácint (1984-) (biológus) Szép Tibor
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
DOI
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2.

001-es BibID:BIBFORM022625
Első szerző:Pap Péter László (ökológus)
Cím:Host-symbiont relationship and abundance of feather mites in relation to age and body condition of the barn swallow (Hirundo rustica) : an experimental study / Péter László Pap, Jácint Tökölyi, Tibor Szép
Dátum:2005
Megjegyzések:We analyzed the host-symbiont relationship and factors determining the abundance of feather mites among individual barn swallows (Hirundo rustica L., 1758) in two different host populations during the breeding season and postbreeding period. By experimentally removing the feather mites from the flight feathers of the birds with an insecticide, we showed that these symbiotic organisms have neither harmful nor beneficial effects on the fitness of the host, supporting the view that mites are commensals. This was indicated by the lack of any difference in the change in wing-feather length, tail-feather length, fluctuating asymmetry in tail-feather length, breeding performance, and survival of the birds between the fumigated and control groups 1 year after the experiment. During the postbreeding period juveniles harbored fewer mites than adults and the difference was also significant between the 1-year-old birds and those over 1 year old in the breeding population. The number of mites did not change after the second year of life of the birds. We hypothesize that the difference in abundance of mites between the age classes can be explained by the low reproductive potential of the mites, which are not able to populate the exploitable space until the second year of life of the host. Alternatively, young birds might provide fewer resources than old birds. The significant negative association between the number of mites and the laying date of female barn swallows seems to support the conclusion that the abundance of mites is condition-dependent. Because there was no relationship between other condition indices for males and females and number of mites, further research is needed to confirm this conclusion.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Canadian Journal of Zoology. - 83 : 8 (2005), p. 1059-1066. -
További szerzők:Tökölyi Jácint (1984-) (biológus) Szép Tibor
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
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3.

001-es BibID:BIBFORM021607
Első szerző:Pap Péter László (ökológus)
Cím:Habitat preference, escape behavior, and cues used by feather mites to avoid molting wing feathers / Péter László Pap, Tibor Szép, Jácint Tökölyi, Steven Piper
Dátum:2005
Megjegyzések:We analyzed the pattern of distribution and the effect of molting on the escape behavior of feather mites on the wing feathers during the nonmolting and molting season of the barn swallow Hirundo rustica. Feather mites showed consistent preference for the second outermost primary, with a steady decrease in proximal distance and avoidance of the outermost primary. Several explanations are suggested to explain this unusual distribution. Further, analyzing the escape behavior of feather mites on molting primaries, we show that mites avoid the feathers destined to be dropped next on molting barn swallows, and in the case of the outermost primary, mites use the ♭♭last moment'' strategy, namely, leaving feathers shortly before it is dropped. Next, we performed an experiment in which we simulated shedding feathers or feathers about to be shed on nonmolting barn swallows, in order to test cues used by feather mites in avoiding molting primaries. Both the vibration of the incised feather and the gap of the pulled feather induced mites to leave primaries situated distally, at two-feathers distance from the manipulated primary, related to the control group. Our results show that feather mites have the ability to perceive the signal produced by the feather that will drop next and by the gap of the missing feather. It remains to be demonstrated, whether feather mites have the ability to perceive the vibration of the feather per se or they perceive the altered airflow caused by the vibrating feathers
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
barn swallow
distribution
Hirundo rustica
symbionts
vibration hypothesis
window hypothesis.
Megjelenés:Behavioral Ecology. - 17 : 2 (2005), p. 277-284. -
További szerzők:Szép Tibor Tökölyi Jácint (1984-) (biológus) Piper, Steven
Internet cím:DOI
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4.

001-es BibID:BIBFORM018803
Első szerző:Pap Péter László (ökológus)
Cím:Increase of feather quality during moult : a possible implication of feather deformities in the evolution of partial moult in the great tit Parus major / Péter L. Pap, Zoltán Barta, Jácint Tökölyi, Csongor I. Vágási
Dátum:2007
Megjegyzések:Here we investigate the change in feather quality during partial post-juvenile and complete post-breeding moult in great tit Parus major by measuring the change in the number of fault bars and feather holes on wing and tail feathers. Feathers grown during ontogeny usually are of lower quality than feathers grown following subsequent moults at independence. This is reflected by higher number of fault bars and feather holes on juveniles compared to adults. Fault bars are significantly more common on tail and proximal wing feathers than on the distal remiges, indicating a mechanism of adaptive allocation of stress induced abnormalities during ontogeny into the aerodynamically less important flight feathers. On the contrary, feather holes produced probably by chewing lice have a more uniform distribution on wing and tail feathers, which may reflect the inability of birds to control their distribution, or the weak natural selection imposed by them. The adaptive value of the differential allocation of fault bar between groups of feathers seems to be supported by the significantly higher recapture probability of those juvenile great tits which have fewer fault bars at fledging on the aerodynamically most important primaries, but not on other groups of flight feathers. The selection imposed by feather holes seems to be smaller, since except for the positive association between hatching date, brood size and the number of feather holes at fledging, great tits' survival was not affected by the number of feather holes. During post-juvenile moult, the intensity of fault bars drops significantly through the replacement of tail feathers and tertials, resulting in disproportional reduction of the total number of fault bars on flight feathers related to the number of feathers replaced. The reduction in the number of fault bars during post-juvenile moult associated with their adaptive allocation to proximal wing feathers and rectrices may explain the evolution of partial post-juvenile moult in the great tit, since the quality of flight feathers can be increased significantly at a relatively small cost. Our results may explain the widespread phenomenon of partial post-juvenile moult of flight feathers among Palearctic passerines. During the next complete post-breeding moult, the total number of fault bars on flight feathers has remained unchanged, indicating the effectiveness of partial post-juvenile moult in reducing the number of adaptively allocated fault bars. The number of feather holes has also decreased on groups of feathers replaced during partial post-juvenile moult, but the reduction is proportional with the number of feathers moulted. In line with this observation, the number of feather holes is further reduced during post-breeding moult on primaries and secondaries, resulting in an increase in feather quality of adult great tits.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Journal of Avian Biology. - 38 : 4 (2007), p. 471-478. -
További szerzők:Tökölyi Jácint (1984-) (biológus) Vágási Csongor István Barta Zoltán (1967-) (biológus, zoológus)
Pályázati támogatás:OTKA
T046661
OTKA
NF061143
Internet cím:DOI
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5.

001-es BibID:BIBFORM013320
Első szerző:Pap Péter László (ökológus)
Cím:Variation in haematological indices and immune function during the annual cycle in the Great Tit Parus major / Péter L. Pap, Csongor I. Vágási, Jácint Tökölyi, Gábor Á. Czirják, Zoltán Barta
Dátum:2010
ISSN:0373-2266
Megjegyzések:We investigated seasonal variation in haematological indices and immune function in the non-migratory Great Tit Parus major over a complete annual cycle. The haematocrit value showed a marked reduction in spring and summer, reaching a lowest value during moult, after which it increased to reach a maximum in winter and spring. The peak in the heterophil to lymphocyte ratio (H/L) during July indicated that Great Tits were the most stressed during the first half of the moulting period. The increase in heterophils and H/L ratio, concurrent with a reduced number of lymphocytes during the breeding season, probably reflected the cost of reproduction in terms of physiological stress and immune suppression. After breeding the number of heterophils and the H/L ratio decreased, reaching a lowest value during winter. The concentration of immunoglobulins followed the seasonal pattern in the number of heterophils, though highest values occurred somewhat later, in July?September during the second part of the moulting period. Our observations indicated large differences in activity throughout the year of different components of the immune system. This suggests differences in function among the components and possibly differences in susceptibility to stress, parasitism and hormones during the annual cycle. When juveniles became independent of their parents, the immunoglobulin concentration increased, whereas other immune measures did not show a significant change. This indicates a rapid increase of at least one component of the immune system after the young fledge.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
Megjelenés:Ardea. - 98 : 1 (2010), p. 105-112. -
További szerzők:Vágási Csongor István Tökölyi Jácint (1984-) (biológus) Czirják Gábor Á. Barta Zoltán (1967-) (biológus, zoológus)
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6.

001-es BibID:BIBFORM030386
Első szerző:Vágási Csongor István
Cím:Correlates of variation in flight feather quality in the Great Tit Parus major / Csongor I. Vágási, Péter L. Pap, Jácint Tökölyi, Edina Székely, Zoltán Barta
Dátum:2011
Megjegyzések:The most important function of moult in birds is the renewal of deteriorated feathers. Worn and holey remiges may incur fitness costs, yet little is known about the factors responsible for the degree of feather wear and sources of variation in feather hole incidence. Here, we report results on variation in feather quality based on a study of three consecutive annual cycles of a Great Tit Parus major population. We found that month, age, sex, weight and the presence of feather holes are the main sources of variation in degree of wear. Juveniles and individuals with lower feather quality (measured through rachis diameter) and with fault bars present had higher feather hole loads. Feather abrasion peaked in the breeding season and was higher in females probably due to higher workload. The lower feather quality of juveniles compared to adults probably arises because of fast ontogeny in contrast to adults' prolonged moult. Our results indicate that feather deformities are positively interrelated and can be used as proxies of feather quality. Our findings on the correlates of feather holes seem partially contradictory with the widespread view that holes are feeding marks of chewing lice. We propose that feather holes are instead minor feather handicaps, at least in Great Tits.
Tárgyszavak:Természettudományok Biológiai tudományok idegen nyelvű folyóiratközlemény külföldi lapban
annual cycle
fault bar
feather deformities
feather hole
feather wear
flight feather quality
Parus major
Megjelenés:Ardea. - 99 : 1 (2011), p. 53-60. -
További szerzők:Pap Péter László (ökológus) Tökölyi Jácint (1984-) (biológus) Székely Edina Barta Zoltán (1967-) (biológus, zoológus)
Internet cím:Intézményi repozitóriumban (DEA) tárolt változat
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