Distribuzione, consistenza ed evoluzione dellepopolazioni di basettino Panurus biarmicus nidifcanti in Italia nel periodo 1980-2006

Brichetti P., Grattin N.

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Abstract:

Panurus biarmicus breeding population distribution, consistence, and trend in Italy. In Italy the bearded parrotbill Panurus biarmicus nests mainly in the eastern part of the Po Valley, with some localized populations near the lakes of Tuscany (Chiusi, Montepulciano, Massaciuccoli) and of Umbria (Colforito and Trasimeno); the southern limit of its breeding range is around the coastal wetlands in Apulia (Lago Salso). At present, 85% of the population is concentrated in three regions (Veneto, Friuli-Venezia Giulia and Emilia Romagna), the remaining 15% being in Lombardy, Tuscany, Umbria and Apulia. After an expansion that began in the ’70s, in the late ’90s this species has experienced a decline both in the breeding range and in the number of individuals; these phenomena got worse in the early 2000. In the period 2003-2006 the breeding population in Italy was estimated at 590-840 pairs, whereas in the mid ’80s it had been estimated at 4,000-10,000 pairs (although we think these latter fgures were too high). The negative trend could be accounted for, at least locally, the loss of suitable habitat (i.e. the burning of reedbeds in late winter, changes in water levels, and, lately, by the heavy presence of Myocastor coypus, which causes changes in the extent and structure of reedbeds). Further studies are needed to better defne the causes of the sharp decline of Bearded Parrotbill in Italy.