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Flight behaviour of Honey Buzzards (Pernis apivorus) during spring migration over the sea.
No full textSpring raptor migration at Ustica, southern Italy
No full textThe island of Ustica, lying at 38°42’N 13°12’E in the Tyrrhenian Sea, is approximately 60 km north of western Sicily and 270 km northeast of the Cap Bon promontory in Tunisia (fig.1). Although covering an area of only 7,600 ha, its isolation makes it attractive to migrant birds. In order to establish the importance of Ustica for the spring migration of raptors in the Mediterranean basin, counts of migrating raptors were made from the highest point of the Falconiera promontory, which dominates the northeast coast of the island, between 22nd March and 20th May 2002.Each spring, thousands of raptors cross the Mediterranean Sea between Africa and southern Italy during their northward migration to European breeding areas. Within this region, the largest concentrations have been reported at the Strait of Messina, between southern mainland Italy and Sicily (fig. 1). Corso (2001) documented an average of 26,062 raptors migrating across the Strait of Messina each spring between 1996 and 2000 (table 1). At this site, raptors crossing the Strait of Sicily, between the Cap Bon peninsula and western Sicily, converge with those migrating northTable 1. Number of raptors observed on Ustica, southern Italy, from 22nd March to 20th May 2002. These are compared with those recorded at the Strait of Messina during spring migration 1996-2000, based on data from Corso (2001). Species Honey-buzzard Pernis apivorus Black Kite Milvus migrans Short-toed Eagle Circaetus gallicus Marsh Harrier Circus aeruginosus Hen Harrier Circus cyaneus Pallid Harrier Circus macrourus Montagu’s Harrier Circus pygargus Pallid/Montagu’s Harrier Circu
Local and regional wind patterns affect spring migration magnitude, flyways and flocking of European Honey-buzzards Pernis apivorus at the Strait of Messina
No full textSummary . During spring migration, a few tens of thousands of European Honey-buzzards wintering in sub-Saharan Africa cross the central Mediterranean to reach their breeding grounds in central-eastern Europe. In so doing they concentrate passage through the Sicilian Channel but choose different flyways in response to different wind conditions. This study investigated the influence of local and regional wind conditions on the movement patterns of this species along the Strait of Messina, a migration bottleneck located between eastern Sicily and southern continental Italy where some raptors fall victim to illegal shooting by poachers each spring. Simultaneous observations occurred at four watchpoints, three on the Sicilian side and one on the continental boundary (Calabrian side). Although northwesterly winds prevailed at the Strait during peak migration days, slightly different local patterns of both horizontal and vertical winds at each observation site affected flocking and shaped the passage of raptors through this bottleneck, broadening the migration front. The results confirm that the magnitude of Honey-buzzard spring migration at the Strait is strongly affected by wind patterns in the Sicilian Channel. In particular, migrants concentrate at this bottleneck after crossing the Channel in northwesterly winds the previous day. In conclusion, by interpreting migratory behaviour both at local and regional scales, this work can help to plan more efficient monitoring of Honey-buzzards through the Strait and improving the siting of conservationist efforts. - Agostini, N., Chiatante, G., Gustin, M., Cento, M., von Hardenberg, J., Dell'Omo, G. & Panuccio, M. (2021). Local and regional wind patterns affect spring migration magnitude, flyways and flocking of European Honey-buzzards Pernis apivorus at the Strait of Messina. Ardeola, 68: 373-390
Two different migration strategies in response to an ecological barrier: Western Marsh Harriers and juvenile European Honey Buzzards crossing the central-eastern Mediterranean in autumn
No full textEnzimi coinvolti nell'assimilazione dello azoto in plantule di grano duro (Triticum durum Desf. cv Simeto)
No full textPotential importance of wind patterns and guidance opportunities for the conservation of the Egyptian Vulture Neophron percnopterus in Italy
No full textMovement ecology and environmental factors are topics of paramount importance to consider when planning conservation programmes for target species. Here we discuss this topic by reviewing the available information related to the Egyptian Vulture Neophron percnopterus, with reference to the remnant breeding population of Southern Italy, of high conservation concern and subject of a long-term captive-breeding re-stocking programme. We describe how adverse wind conditions over the Central Mediterranean Sea make the sea-crossing challenging with detrimental effects on the survival of inexperienced birds, and coupled this information with count data of migrating Egyptian Vultures. Furthermore, we indicate how low population size and scarce opportunities in meeting migrating conspecifics could potentially lead juvenile Egyptian Vultures to follow unfavourable migratory routes, with possible repercussions on survival. We postulate how these concomitant factors could be indirectly influencing the long-term survival of this small population, principally affected by anthropogenic threats. We also discuss how the same factors could actually be affecting captive-bred young individuals released in late summer in southern continental Italy, in the framework of the restocking programme. An integrative approach with tailor-made release methods, which also takes into account the age of released birds and geographical and environmental factors, would likely be useful for a more goal-oriented and long-lasting conservation outcome, for the preservation of this endangered scavenger
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
INHIBITION BY GLUFOSINATE OF GLUTAMINE SYNTETHASE OF CULTURED CELLS OF CARROT (DAUCUS CAROTA, L.): EFFECT OF GLUTAMATE.,
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