Navegando por Assunto "Amazona amazonica"

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Acesso aberto (Open Access)
Comportamento do papagaio-do-mangue Amazona amazonica: gregarismo, ciclos nictemerais e comunicação sonora
(Universidade Federal do Pará, 2007) MOURA, Leiliany Negrão de; SILVA, Maria Luisa da; http://lattes.cnpq.br/2101884291102108
In this study we carried through the Orange-winged-parrot Amazona amazonica census in a roosting site, the Parrots Island, located next to Belém, Pará. With the countings we verify that the total number of parrots, the number of isolated individuals, couples, groups of three, four and five individuals presented a fluctuation, indicating reproductive seasonality, that influences in the number of individuals with the reduction of its participation in the groups that sleep in the island during its reproductive period, since the species supplies parental cares to the offsprings. In relation to the nychtemeral cycle, we evaluate the influence of abiotic factors in the schedules of displacements of the individuals of this population in the roosting site. We establish a form to register the frequency of its arrival or exit from minute to minute and relate the data gotten with the sunset and sunrise schedules. We verify that the percentage average of individuals that arrives and leaves is significantly greater after sunset and before sunrise, respectively, and that adverse weathers conditions influence significantly in the daily movement of the parrots, masking the real positioning of the Sun, advancing or delaying its arrival and exit of the roosting site. Although the Orange-winged-parrot is a diurnal avian, they dislocate in schedules of low luminosity, being the photoperiodism a entrainment agent of its activities. About its acoustic communication, it presents 9 vocalizations in the vocal repertoire during the reproductive period, related to three different behavior categories. Moreover, it exists an individual difference in its flight contact call and populational dialects between the studied populations.
Acesso aberto (Open Access)
Influence of the nycthemeral cycle on the roosting behaviour of the Orange-winged Amazon
(2012-06) MOURA, Leiliany Negrão de; SILVA, Maria Luisa da; VIELLIARD, Jacques Marie Edme
Environmental stimuli exert important effects on the expression of the endogenous rhythms. Daily movements of groups of parrots in response to the light/dark cycle have been studied by several researchers. However, the factors modifying the intrinsic rhythmicity of this behaviour remain little known. This study describes how the nychthemeral/circadian periodicity of roost daily movements of the Orange-winged Amazon Amazona amazonica is modified by weather factors. Numbers of parrots arriving or leaving the roosting site Ilha dos Papagaios were determined on a minute by minute basis. More parrots have significantly arrived at the roost after sunset than before, while more parrots have significantly left the roost before sunrise than after. The peak exodus of parrots occurred at 23 ± 5.24 minutes before sunrise, when the average light intensity was 1 lux. The peak influx of parrots occurred at 6 ± 6.1 minutes after sunset, when the average light intensity was 50 lux. By altering ambient light intensity, weather conditions have significantly influenced the arrival and departure times, with parrots leaving later and arriving earlier when conditions were overcast at the roost site.