824 resultados para MIGRATORY BIRDS


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Teoksen Finska fogelägg tekstiosan saksan- ja englanninkielinen laitos. Ilmestynyt ilmeisesti 2 vihkona: I-III vihko 1881: XXXII s., IV vihko [1881?]: s. XXXIII-XL. - Julkaiseminen nähtävästi jäänyt kesken. - Teoksen kuvalehtiä ei ole painettu erikseen saksan- ja englanninkielisinä.

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In recent years haemosporidian infection by protozoa of the genus Plasmodium and Haemoproteus, has been considered one of the most important factors related to the extinction and/or population decline of several species of birds worldwide. In Brazil, despite the large avian biodiversity, few studies have been designed to detect this infection, especially among wild birds in captivity. Thus, the objective of this study was to analyze the prevalence of Plasmodium spp. and Haemoproteus spp. infection in wild birds in captivity in the Atlantic Forest of southeastern Brazil using microscopy and the polymerase chain reaction. Blood samples of 119 different species of birds kept in captivity at IBAMA during the period of July 2011 to July 2012 were collected. The parasite density was determined based only on readings of blood smears by light microscopy. The mean prevalence of Plasmodium spp. and Haemoproteus spp. infection obtained through the microscopic examination of blood smears and PCR were similar (83.19% and 81.3%, respectively), with Caracara plancus and Saltator similis being the most parasitized. The mean parasitemia determined by the microscopic counting of evolutionary forms of Plasmodium spp. and Haemoproteus spp. was 1.51%. The results obtained from this study reinforce the importance of the handling of captive birds, especially when they will be reintroduced into the wild.

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The semipalmated sandpiper Calidris pusilla and the spotted sandpiper Actitis macularia are long- and short-distance migrants, respectively. C. pusilla breeds in the sub-arctic and mid-arctic tundra of Canada and Alaska and winters on the north and east coasts of South America. A. macularia breeds in a broad distribution across most of North America from the treeline to the southern United States. It winters in the southern United States, and Central and South America. The autumn migration route of C. pusilla includes a non-stop flight over the Atlantic Ocean, whereas autumn route of A. macularia is largely over land. Because of this difference in their migratory paths and the visuo-spatial recognition tasks involved, we hypothesized that hippocampal volume and neuronal and glial numbers would differ between these two species. A. macularia did not differ from C. pusilla in the total number of hippocampal neurons, but the species had a larger hippocampal formation and more hippocampal microglia. It remains to be investigated whether these differences indicate interspecies differences or neural specializations associated with different strategies of orientation and navigation.

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Tiene como objeto explorar los pájaros y ofrecer respuestas a muchos de los qué, por qué y cómo que los niños pequeños preguntan sobre el mundo que les rodea. Para ayudar a los niños a entenderpor qué los pájaros tienen plumas,cómo las aves migratorias encuentran su camino. Cada dos páginas hay tres secciones organizadas por temas:un Ahora sé, es una revisión de los principales aspectos que refuerza lo aprendido. Eso es asombroso, ofrece características destacadas de la costa. Mira y encuentra sirve para alentar a los niños a identificar y asociar nombres con imágenes.

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The recovery of vegetation in Mediterranean ecosystems after wildfire is mostly a result of direct regeneration, since the same species existing before the fire regenerate on-site by seeding or resprouting. However, the possibility of plant colonization by dispersal of seeds from unburned areas remains poorly studied. We addressed the role of the frugivorous, bird-dependent seed dispersal (seed rain) of fleshy-fruited plants in a burned and managed forest in the second winter after a fire, before on-site fruit production had begun. We also assessed the effect on seed rain of different microhabitats resulting from salvage logging (erosion barriers, standing snags, open areas), as well as the microhabitats of unlogged patches and an unburned control forest, taking account of the importance of perches as seed rain sites. We found considerable seed rain by birds in the burned area. Seeds, mostly from Olive trees Olea europaea and Evergreen pistaches Pistacia lentiscus, belonged to plants fruiting only in surrounding unburned areas. Seed rain was heterogeneous, and depended on microhabitat, with the highest seed density in the unburned control forest but closely followed by the wood piles of erosion barriers. In contrast, very low densities were found under perches of standing snags. Furthermore, frugivorous bird richness seemed to be higher in the erosion barriers than elsewhere. Our results highlight the importance of this specific post-fire management in bird-dependent seed rain and also may suggest a consequent heterogeneous distribution of fleshy-fruited plants in burned and managed areas. However, there needs to be more study of the establishment success of dispersed seeds before an accurate assessment can be made of the role of bird-mediated seed dispersal in post-fire regeneration

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En aquest treball s'exposen els resultats obtinguts en la campanya 1994 d'anellament d'ocells inclosa dins del projecte italià Piccole Isole. Es demostra que el factor meteorològic afecta directament la fenologia migratòria de diferents espècies d'ocells. Es pretén també estudiar la influència dels diferents hàbitats en el nombre i en la diversitat de captures. Es recullen també en aquest treball les principals espècies visualitzades durant la campanya, com també l'elevat nombre de controls estrangers recuperats. Dintre de les captures i l'anellament posterior, destaca sobretot la d'un becadell gros (Gallinago media) fets per primera vegada a la peninsula Ibèrica

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Birds, both companion and wild, have become frequent patients in veterinary clinics and hospitals as well in wildlife rehabilitation centers in the last two decades. In emergency situations, it is imperative to give the best critical care to these patients, which frequently implies reversing shock and re-establishing homeostasis. In order to do so, a blood transfusion can be life-saving. It is important to the clinician to properly evaluate these critical patients and decide when to administer blood or blood products.