6 research outputs found

    Doñana. Acta vertebrata. vol 22 (1/2)

    Get PDF
    Relación entre el uso del espacio del mito (Aeghitalos caudatus) y la disponibilidad de artrópodos durante el periodo primavera-veranoHábitos frugívoros de la corzuela parda (Mazama gouazoubira, Ficher, 1814) (Mammalia: Cervidae), en un ambiente secundario de yungasComparación entre varias técnicas de estimación de la edad en zorros, Vulpes vulpes, de Doñana (sur de la Península Ibérica)Características morfológicas de los corzos (Capreolus capreolus) de las sierras de Cádiz-Málaga.Etograma y relación de la conducta con el hábitat y con la edad en el ñandú (Rhea americana)Variación estacional del área de campeo de Oxymycterus rufus (Rodentia: Cricetidae), en el delta del rio Paraná, ArgentinaTracking of a female american mink (Mustela vison, Schreber, 1777) in NE Spain.Nidificación de láridos en la provincia de Almeria (SE Ibérico)Expansión del área de distribución de Microtus arvalis asturianus Miller, 1908 (Rodentia, Arvicolidae) en la meseta norte (España)Diet of the thekla lark, Galerida theklae, in a shrubsteppe of southeastern SpainAlimentación de la lechuza campestre (Asio flammeus) en la submeseta norte (España), durante el periodo reproductorUso de cajas anidaderas por lirones grises (Glis glis) y ratones leonados (Apodemus flavicollis) en el norte de la Península Ibérica.Theoretical flight ranges of waders resting in the Ebro Delta during autumn migrationPeer reviewe

    Cooperative breeding between males in the Greater Rhea Rhea americana

    Get PDF
    Peer Reviewe

    Adoption of unrelated young by greater rheas

    No full text
    The benefits, if any, of the adoptive behavior of male Greater Rheas (Rhea americana) towards unrelated young while leading their offspring are not known. Therefore, we quantified adoption by Rheas in an agricultural area of Rio Grande do Sul, Brazil, in order to quantify the potential benefits and the recipients of these benefits. Adult males frequently adopted (23%), were more vigilant and protective than non-adopters, and ended up leading larger groups of young than non-adopting males. The adopted chicks were usually not more than 1-wk old and survived in greater proportion than the adopter's own offspring.Peer Reviewe

    Mating behavior of the male Greater Rhea

    No full text
    During mating, and during the phases known as solitary male, harem formation, and harem, male Greater Rheas (Rhea americana) became vigilant to assure the elimination of competitors. High rates of harem defense and male expulsion were observed at the start, with levels decreasing gradually through the phases of mating, and male-male fighting mainly limited to the phase of harem formation. Courtship was nonexistent early in the mating period, reached a high level during the phases of harem formation and harem, then declined markedly just before harem breaking. The rates of all male social activities decreased significantly just before harem breaking.Peer Reviewe

    Behavioural responses of captive-born greater rheas Rhea americana Linnaeus (Rheiformes, Rheidae) submitted to antipredator training

    No full text
    Human activities have been diminishing greater rhea Rhea americana (Linnaeus, 1758) populations throughout their natural distribution. The reintroductions of captive-born greater rheas have been tried but without success; since the individuals reintroduced were killed by predators. Captive-born animals that have been isolated from predators for many generations can lose their predator recognition abilities. To enhance the survival rates of the reintroduced animals, researchers are now using antipredator training techniques. We studied the response of 15 zoo-borne greater rheas to antipredator training. The animals were divided into three groups: two test groups and one control group. We ran 15 antipredator tests and four control testes with each group. Antipredator tests consisted of pairing a taxidermized predator model or a real predator (domestic dog) with a simulation of a capture procedure. Control tests consisted of presenting the predator model (jaguar) to the birds, after training but not associating it with an aversive event and recording behavioural responses. All tests were video-recorded and analysed a posteriori. Results showed that the trained rheas responded appropriately to the predators, becoming more vigilant and that there was considerable individual differences in response to antipredator training. The results demonstrated that antipredator training is effective and therefore an invaluable tool for reintroduction projects involving greater rheas. Furthermore, the methods employed in this research project should be applicable to other species of flightless birds.<br>As atividades humanas têm diminuído as populações de emas Rhea americana (Linnaeus, 1758) por toda sua área de distribuição. Reintroduções de emas nascidas em cativeiro têm sido tentadas, mas sem sucesso, uma vez que os indivíduos reintroduzidos são mortos por predadores. Animais nascidos em cativeiro que foram isolados de seus predadores por várias gerações podem se tornar incapacitados do seu reconhecimento. Para aumentar as taxas de sobrevivência dos animais reintroduzidos, pesquisadores têm utilizado técnicas de treinamento anti-predação. O objetivo deste trabalho foi a aplicação de treinamento anti-predação em emas nascidas em cativeiro e avaliação de suas respostas comportamentais. Foram treinadas 15 emas adultas. Os animais foram divididos em três grupos: dois grupos-teste e um grupo controle. Foram realizados 15 testes anti-predação e quatro testes-controle com cada grupo. O teste anti-predação consistia em parear um modelo taxidermizado de predador (onça-pintada) ou um predador real (cachorro doméstico) com uma simulação de captura. Os testes-controle consistiram na apresentação do modelo do predador (onça empalhada) às aves, depois do treinamento, mas sem a associação com o estímulo aversivo. As respostas comportamentais foram filmadas e os comportamentos anotados posteriormente. Os resultados mostraram que as emas responderam apropriadamente aos predadores, se tornando mais vigilantes, e que existem diferenças individuais evidentes em resposta ao treinamento anti-predação. Os resultados demonstraram que o treinamento anti-predação pode ser uma ferramenta valiosa para futuros projetos de reintrodução envolvendo emas. Além disso, os métodos empregados nesta pesquisa podem ser aplicados a outras espécies de aves não-voadoras
    corecore