| Titre : | The population of Bittern Botaurus stellaris in the Diaccia Botrona marsh (central Italy): Four years of census (1991-1994) |
| Titre original: | The population of Bittern Botaurus stellaris in the Diaccia Botrona marsh (central Italy): Four years of census (1991-1994) |
| Auteurs : | L. Puglisi, Auteur ; Fontanelli A., Auteur ; A. Perfetti, Auteur ; M. Taverni, Auteur |
| Type de document : | Article |
| Dans : | Avocetta (19 1995) |
| Article en page(s) : | 182-188 |
| Mots-clés: | oiseau butor reedbed ITALIE PALEARCTIQUE census abondance citation anglais |
| Résumé : |
The Bittern population of a marshland in Central Italy was censused using a network of listening stations. This technique appears to be sufficient to quantify the population being examined, but does not allow an accurate analysis of the positions of the booming males. The data in the literature, dating from 1974, indicate that the population studied had a progressive increase up to the early 1990s (from 0-1 to 14-18 males) and then a phase of decline (with 7-9 in 1994). These variations seem mainly due to the changes in the marsh vegetation. This was positive at first, thinning out the reedbeds, then negative with their preogressive reduction. However, the role of primary importance of the studied population in Italy has been confirmed.- Etude descriptive sur butor censused pendant 4 ans le long de sentier d'écoute après l'aube. Nb de boomers diminue de 14 (1991) à 7 en (1994). Déclin associé à dégradation de la roselière du à la création de roubine et de marais de chasse qui ont éventuellement permis l'entrée d'eau de mer. Surface couverte en roselière en décroissance exponentielle. Number of audible contacts vary within and among days. "Further research on the phenology of the booming activity is therefore necessary to improve the census technique." Citations from Handbooks: Bittern needs flooded beds of not too thick vegetation interrupted by swamps, ponds and ditches. Difficult to identify feeding areas during nesting: birds more elusive or nocturnal. Home range can be defined only via telemetry. |



