Wyniki wyszukiwania

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Patagonki z kolonii w El Condor - przyszlosc i zagrozenia

100%

Masello J. F., Quillfeldt P.

Woliera

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2004

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nr 10

16-23

2

Functional characterization of begging calls in Thin-billed Prions Pachyptila belcheri chicks

80%

Duckworth A., Masello J. F., Mundry R., Quillfeldt P.

Acta Ornithologica

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2009

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tom 44

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nr 2

Chicks beg to solicit food and care from their parents. Previous studies of nocturnally feeding Thin-billed Prions (Pachyptila belcheri) showed that chicks convey information about their condition to their parents by means of begging calls. However, those studies used tape-recorders with a limited recording duration, which precluded the recording of complete nights, so only the first begging sessions per night were analysed. Here we present data on begging call intensities and the acoustic parameters of begging elements obtained using digital voice recorders, which enabled complete nights to be recorded. Chicks used from one to five begging sessions per night. We found that the parameters of the first calling sessions did not reflect body condition, whereas the duration of begging sessions and the number of begging calls over the whole night was correlated with the chicks' body condition and the sizes of the meals delivered by the parents. The acoustic parameters of begging call elements were not correlated with body condition. Chicks did not change call frequencies according to their state of nutrition. All call parameters, including the acoustic parameters of chick begging calls, were highly chick-specific. We further tested for age effects and found strong correlations between call features and the age of chicks. The results of the present study show that some begging parameters, e.g. the duration of begging sessions and the number of begging calls over the whole night, are connected with condition, while others, such as acoustic parameters, are linked with individual chick recognition.

3

Analysis of ring recoveries of European Turtle Doves Streptopelia turtur - flyways, migration timing and origin areas of hunted birds

80%

Marx M., Korner-Nievergelt F., Quillfeldt P.

Acta Ornithologica

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2016

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tom 51

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nr 1

Knowledge about flyways, breeding and overwintering sites is important for conservation efforts, but little is known about migration patterns and population connectivity of declining European Turtle Doves Streptopelia turtur. EURING ring-recovery data were used to estimate directions and proportional usage of flyways. The timing of migration was compared along these routes and breeding origins of shot individuals were determined. Ring recoveries of Czech, Hungarian, British, German and French birds suggested three main flyways with westerly, central and easterly directions. The proportional usage was estimated by multinomial mark-recovery models. Major parts of French (62%), German (92%) and British (94%) Turtle Doves followed a western flyway. Czech birds used the central route (56%) and 55% of Hungarian birds followed the eastern flyway. Thus, a migratory divide between the Czech Republic and Germany could be suggested. The timing of migration showed a similar latitudinal pattern of migration along all flyways. Birds were at the breeding grounds in June and July and from September to April in their southernmost distribution ranges. Outward migration started in August. Return migration was still evident in May. The majority of reported hunted doves were from the 1960s and 1970s. High hunting numbers were present in September, April and May. France and Spain mainly shot birds from the UK and France. In Italy predominantly Italian birds were shot. Doves shot in Greece mostly came from the Czech Republic. Given the decreasing population numbers, large ringing numbers seem unlikely in the future. Thus, low recovery numbers in recent decades parallel both, the population decrease and a lower ringing activity.

Ograniczanie wyników

2 Acta Ornithologica

1 Woliera

3 Quillfeldt P.

2 Masello J. F.

1 Duckworth A.

1 Korner-Nievergelt F.

1 Marx M.

1 Mundry R.

1 2016

1 2009

1 2004

Patagonki z kolonii w El Condor - przyszlosc i zagrozenia

Functional characterization of begging calls in Thin-billed Prions Pachyptila belcheri chicks

Analysis of ring recoveries of European Turtle Doves Streptopelia turtur - flyways, migration timing and origin areas of hunted birds