Volume 30 - N. 1/2
1/2 2006

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Volume 30 - N. 1/2



  1. Biological significance and conservation of biogeographical bird populations as shown by selected Mediterranean species

    Massa B.

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    14 33

    From the conservation point of view there is an important difference between species that are treated as whole and species
    considered as separate subspecies; these represent important components of biodiversity and deserve conservation for their potential evolution and their characteristics. EU Bird Directive shows an attempt to protect subspecific taxa, when really necessary for conservation
    purposes. There are some examples of species regarded as secure, if considered as whole, that turn out to be endangered or critically
    endangered when treated as subspecies (e.g. Mediterranean storm petrel, lanner falcon, rock partridge, Andalusian hemipode, long-tailed tit and crossbill). Status of some species should have to be modified, basing information on more objective comparison with those
    available for related species (e.g. the pairs Manx and Yelkouan shearwaters, European and spotless starling, and North African blue tit).
    Moreover, some species have a very restricted distribution, that might be considered an endemic bird area, holding two or more species
    with a range covering less than 50,000 km2 (e.g.: Marmora’s warbler, Cyprus warbler, Cyprus wheatear and Corsican citril finch). Here
    I suggest to reconsider, among future conservation priorities, the status of a number of S European species in the light of previous considerations, avoiding some paradoxes, such as incongruity of risk level, when compared to other bird species.

  2. La cicogna nera Ciconia nigra  in Italia: tendenze storiche,biologia riproduttiva e fenologia

    BORDIGNON L., BRUNELLI M. , VISCEGLIA M.

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    3 31

    The black stork Ciconia nigra in Italy: historical trends, breeding biology and phenology. During the first national survey on
    black storks (1800-2005), 3727 records were collected from bibliography and direct observations. The species is present mainly during
    migration in spring generally in southern regions and along the eastern coast of the country and in autumn in northern regions and along
    the Tyrrhenian coast. Altough rare, wintering is increasing, and 4-6 breeding pairs has been recorded since 1994 in Piedmont, Latium,
    Basilicata and Calabria. Habitat deterioration, poaching and electrocution are the main threats in Italy for the species.

  3. Alimentazione frugivora  autunno-invernale dell’occhiocotto Sylvia melanocephala  e della capinera Sylvia atricapilla  in aree costiere del Lazio

    CASTALDI A., GUERRIERI G.

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    8 36

    Autumn-winter consumption of fruits by Sardinian warbler Sylvia melanocephala and blackcap Sylvia atricapilla in coastal
    areas of Latium (central Italy). We studied for five years (1996-2000) the autumn-winter consumption of fruits by the Sardinian warbler
    and blackcap in Mediterranean scrubs of the Latium coast. The number of Sardinian warblers and blackcaps feeding on different fruiting species changed in different study area and months. The most used fruiting plants by Sardinian warbler and blackcap were Pistacia
    lentiscus and, in some areas, Olea europaea europaea. In most cases, the fruiting species preferred by Sardinian warbler or blackcap were
    different. In general, Sardinian warbler used the fruiting plants at smaller extent than the blackcap. The number of blackcaps feeding on
    fruits was maximum in autumn, whereas the number of Sardinian warblers was maximum in some areas in winter. The major consumption of fruits observed in the blackcap is probably related to its higher migratory

  4. Ecologia riproduttiva del cuculo Cuculus canorus  in una zona umida  dell’Italia Centrale

    Quaglierini A.

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    5 29

    Breeding ecology of the cuckoo Cuculus canorus in Central Italy. In this study I present the results of a 14-years survey (1992-
    2005) of cuckoo parasitism towards breeding warblers in the lake of Massaciuccoli, a large wetland area in Central Italy. Data about density of singing cuckoo males, characteristics of parasitized nests, parasite eggs, and breeding success have been collected. A mean density of 4.2 singing males/km2 was found. Cuckoo exclusively parasitized nests built on Phragmites australis. Parasitized nests were mainly sited in dense reed-beds close to open water. Minimum distance between two active and parasitized nests was 350 m. Cuckoo egglaying, occurring between April 28th and July 27th (median date 4th June), coincided with the laying period of selected host species. Parasitism frequencies resulted to be 8.9% for the reed warbler Acrocephalus scirpaceus, 13.9% for great reed warbler A. arundinaceus and
    0.8% for moustached warbler A. melanopogon. A single cuckoo egg was found in 93.5% of parasitized nests and two eggs in the remaining 6.5%. The eggs laid in great reed warbler’s nests were larger than the ones laid in reed warbler’s nests. Mean duration of incubation
    of cuckoo eggs was 11.7 days. Hatching success was 63.6%, breeding success was 56.1%. Mean fledging period was equal to 19.9 days.
    Feeding rates of cuckoo nestlings varied from 20.6/h for 10-day old nestlings to 51.4/h for 20-day old nestlings.

  5. Evoluzione delle popolazioni di Laridae  e  Sternidae  nidificanti nelle Valli di Comacchio nel periodo 1977-2001

    Brichetti P., Foscolo Foschi U.

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    3 30

    Population trends of Laridae and Sternidae breeding in the Comacchio Lagoon (NE Italy) between 1977 and 2001. The
    Comacchio Lagoon represents one of the most important breeding areas in the Mediterranean for Laridae and Sternidae and, at a national level, on area of concentration and propagation of several species of conservation interest. Censuses of nests were made on foot or by
    boat during peak colony occupancy, whereas the estimated size of the Larus michahellis population has been partly based on the count
    of adults showing reproductive behaviour. Between 1977 and 2001, 96897 breeding pairs were counted, with an average of 3876 pairs
    per year, of which 41636 belonged to four species of Laridae and 55261 to five species of Sternidae, excluding a single case of nesting
    by Hydroprogne caspia. In the first five years, there was a progressive increase in the Laridae and Sterindae population, followed by a
    long period of marked fluctuation which gave way to five to six years of clear decline, with evidence of a slight recovery in numbers in
    2000-01. The negative trend, which was recorded as from 1993-95, may be related to environmental changes in the breeding habitats and
    to the marked increase and range expansion of Larus michahellis. Around 1991-92, a redistribution of the colonies occurred and, following this, the populations of some species, particularly Larus melanocephalus and Sterna sandvicensis, started to colonize new costal
    wetlands in the upper Adriatic Sea. Such changes may be directly related to the concomitant population increase of Larus michahellis.
    In the course of the last decade, the percentage in numbers of the local populations with respect to the national ones has overall decreased
    except for Larus genei and, above all, Larus michahellis, the only species to have shown a continuous increase from 1977-2001, which
    lead to the progressive colonization of the whole lagoon area.

  6. Densità e biologia riproduttiva del grillaio  Falco naumanni nella piana di Gela (Sicilia)

    Mascara R.,, Sarà M.

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    12 40

    Density and breeding biology of the lesser kestrel Falco naumanni in the Gela Plain (southern Sicily). The lesser kestrel Falco naumanni population of the Gela Plain (southern Sicily) has been monitored for three years (2003-2005) in a study area of 450 km2.
    The results were compared with those from two earlier censuses (1981 e 2001). In the study period, 48 colonies were recorded, 83.3%
    of them in rural houses, and the population reached 260 (range 233-287) pairs. The lesser kestrel in the Gela Plain was continuously
    increasing since 1981, when only 17-21 pairs were present in 7 colonies. During the 2004-2005, 135 nests were detected and 339 birds
    (330 nestlings and 9 adults) were ringed. The mean clutch, brood and fledgling sizes and productivity were among the highest so far
    recorded in the European species’ range. Nonetheless, in 2005, the 9.1% of colonies were destroyed by black rats Rattus rattus and the
    7.8% by men. The area hosts nearly one-third of the whole Sicilian population and represents one of the most important Italian populations. Current land use, based on traditional cereal and semi-intensive farming, is the main reason for the observed population increase.
    The species avoids the coastal part of the study area due to industrial farming (green-houses) and urbanization. The planned agricultural turn-over under the auspices of the CAP, which includes the development of irrigation schemes and expansion of industrial farming
    toward inland, seriously threatens the whole Gela Plain and urges for the implementation of conservation measures.

  7. Assessment of raptor migration and status along the Tsangpo-Brahmaputra  corridor (India) by a local communities participatory survey

    CHETTRI N., RASTOGI A., SINGH O. P.

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    4 34

    A raptor survey based on local knowledge was undertaken in 45 villages along Siang River valley, a part of Tsangpo-Brahmaputra corridor in Arunachal Pradesh, India during summer and autumn in 1999 and a comprehensive list of raptors of the area was
    prepared. The list was prepared involving the local people through systematic questionnaire using participatory processes. Elders and
    knowledgeable persons of the villages were involved in the process to get the best baseline information on raptors of the study area. The
    questionnaire was designed to address the status of raptors, their habitat use patterns, and migratory habits. The results were then compared with recent studies made by different experts from the region. Most survey records and previously documented data were found to
    be similar to each other, suggesting reliability of local knowledge. The study is a model for similar local-population-based research either
    for gap analysis, rapid environmental assessment or in areas where there is limitation for exclusive study and need for immediate effective conservation measures. We suggest to undertake a systematic survey and monitoring to confirm the presence of those species which
    were uncertain in the local knowledge. This research shows the importance of local participation, community involvement, and traditional knowledge in raptor conservation.

  8. Variazioni stagionali di abbondanza dell’allodola Alauda arvensis  in un’area agricola lombarda

    Ferlini F.

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    7 32

    Seasonal variations of abundance of the skylark Alauda arvensis in an agricultural area of Lombardy (N Italy). I collected data on the skylark’s abundance in an agricultural area in
    Lombardy between December 2004 and November 2005. Skylark
    reached the maximum density (6.2 birds/10 ha) in the second half
    of December. In winter the number of birds per flock averaged
    14.4 with a strong preference for crop-rotated meadows. During
    the breeding season the skylark’s density was stable, but decreased in summer. The number of birds per flock (6.6) in autumn was
    less than in winter.

  9. Indagine su alcuni roost invernali di smeriglio Falco columbarius  in provincia di Mantova

    GRATTINI N., LONGHI D., NOVELLI F.

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    12 35

    Winter roosts of merlin Falco columbarius in the Province of Mantua. In Italy, the merlin Falco columbarius is a regular migrant and wintering species. However, data on distribution
    and behaviour in our country are scarce. For instance, very little
    is known about winter roosts, which have been described in other
    countries. From 2002 to 2005 winters, three roosts were monitored in the Province of Mantua (Northern Italy). The number of
    individuals at roosts reached the maximum between December
    and February. Relative peaks were in late October-early November and in March, probably because the arrivals of migratory
    birds. In the three years of this study, the maximum number of
    merlins in the Province of Mantua was 40-50 individuals, representing about 3% of the whole Italian wintering population
    (approx. 1500 individuals). The results of the present work confirm the importance of these wintering roosts for this falcon.

  10. Esperienza di monitoraggio su vasta  scala della migrazione autunnaledel biancone Circaetus gallicus  in Italia e  nel  Mediterraneo centrale

    RUGGIERI L., PREMUDA G., BAGHINO L., GIRAUDO L.

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    4 23

    A large-scale survey of the autumn migration of shorttoed eagles Circaetus gallicus across Italy and the Central Mediterranean. In the present study, we report the results of a 5-year
    survey of the short-toed eagle Circaetus gallicus autumn migration from 41 watchsites. Of the 2761 individuals observed in active migration, 89.9% passed by 3 main watchsites (39.8% on the
    Apuane Alps, 33.5% at Arenzano and 16.5% in Stura Valley).
    Flight direction analysis at 14 minor watchsites located along the
    western slope of Apennines shows that the migratory route is
    directed mainly from SE to WNW in order to avoid the crossing
    of the northern Tyrrhenian Sea. Seventy percent of the migrants
    were adults, 20% were juveniles, and 10% older immatures.
    Analyses of 227 different migrating flocks where ageing was possible showed that 49.7% of the adult birds migrated alone, 31.6%
    together with other adults and 18.7% together with juveniles.
    Conversely, 30.7% of juveniles migrated alone, 6.4% together
    with other juveniles, and 61.2% together with one or more adults.
    This confirms that short-toed eagles migrate across Mediterranean basin by making a circuitous route towards France to avoid
    extensive sea crossing; moreover, our data suggest information
    transmission about the migration route, since a proportion of the
    juveniles appear to learn the migratory route by migrating together with the adults.

  11. Resoconto Ornitologico Italiano – Anno 2004

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    16 32
  12. Resoconto Ornitologico Italiano – Anno 2005RecensioniOrnitologia italiana su riviste straniere

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    8 40