Volume 33 - N. 1
June 2009

Avocetta
Volume 33 - N. 1



  1. La lista CISO-COI degli Uccelli italiani – Parte prima: liste A, B e C

    Fracasso G., Baccetti N., Serra L.

    Abstract     Read Article       Download
    56 233

    The CISO-COI list of Italian birds – The A, B and C lists. The Italian Ornithological Committee (COI) works within the Italian
    Centre for Ornithological Studies (CISO) with the specifc assignment of compiling and updating the list of Italian birds. Three codes have
    been attributed to each species belonging to the list of Italian birds: an alphabetic code referred to the origin of the species in the territory
    (AERC code from A to E) and two codes referred respectively to the status of occurrence and breeding. Codes for the last two categories
    vary from 1 to 4 and are determined by the frequency of respective records within given time intervals. For the taxonomy, we adhered to
    the scientifc nomenclature and systematic order applied by AERC and BOU for the compilation of the respective lists and following taxonomic recommendations. Some Italian common names have been changed in accordance with the CISO working group committed to
    review the Italian nomenclature of the birds of the world.

  2. Breeding biology of the Long-legged Buzzard Buteo rufnusin SE Bulgaria, nesting also in quarries

    Milchev B.

    Abstract     Read Article       Download
    25 125

    Long-legged Buzzard Buteo rufnus breeding numbers have not undergone any signifcant changes in four gorges in SE Bulgaria during the time period 1994-2007. Between 12 and 16 pairs have nested there, which makes one pair per 0.8 – 2.8 km gorge length,
    with minimum 0.9 km distance between neighbouring nests. In the absence of natural rocks the birds prefer rock quarries to trees. They
    build their nests on massive rocks (min 15 m length; min 10 m height), predominantly with southern and western exposition (78 %, n =
    32). Nests are usually located on rock terraces, without any prominent shelter (87 %, n = 21). The nests vary between 0.5 -1.1 m (mean
    0.71, sd 0.18) in diameter and 0.15 – 0.25 m (mean 0.20, sd 0.04) in height (n = 21 nests on rocks). The clutch size has been 2 – 3 eggs
    (1 – 4; n = 12 nests) and the brood size has ranged between 1 – 3 young, mostly 2 (50 %, n = 16 nests). The pairs nesting in the quarries
    feed mainly on small and average-sized mammals and lizards from the open areas, the voles Microtus spp. and European souslik Spermophilus citellus constituting 41 % of the prey. No signifcant changes have been observed in their diet throughout years, but differences
    between different nests are signifcant (χ²[32] = 67.58, p < 0.001). In fve locations they bred jointly with the Eagle Owl Bubo bubo, with a distance of 60 - 650 m from their nests. The Eagle Owl seems not to challenge the breeding of the Long-legged Buzzard in quarries and natural rocks.

  3. Agro-biodiversity evaluation in Sicilian farmlands entered into agri-environment scheme agreements

    Massa B., Siracusa M.

    Abstract     Read Article       Download
    24 64

    To test if the application of Rural Development Regulation 1257/1999 played a possible role in maintaining or increasing biodiversity, monitoring of the avifauna has been carried out in 2004-2005. On the whole, 836 point counts were carried out, 418 in spring
    and 418 in winter, evenly shared between 16 farmlands entered into F2 and F4 agri-environmental measures, and an equal number of “not
    enhanced” farmlands, which represented test-farms and control-farms, respectively. Between bird frequencies within test-farms and control-farms statistical differences have been dected; farms entered into agri-environmental measures showed, on average, higher values of
    species, frequency of occurrence and “priority” species than controls, stressing a general issue: within enhanced farmlands bird communities are richer in species and priority species number. A remarkable species turnover between spring and winter communities has been
    observed. This may be due to farmland management which eventually influenced in some way the presence of more ecologically exigent
    species, through the seasons.

  4. Breeding ecology of the Pied Avocet Recurvirostra avosetta in AghGol wetland, Hamedan Province, Iran

    Barati A., Nouri V. S.

    Abstract     Read Article       Download
    24 138

    The breeding ecology of the Pied Avocet Recurvirostra avosetta was studied during the 2008 breeding season in AghGol wetland, Hamedan province, western Iran. The breeding parameters, i.e. laying date, clutch size, brood size, nest site characteristics, breeding
    success and nestling body mass at hatching were taken into consideration. Egg laying occurred from 10 May to 9 June. Mean clutch size
    was 3.13 ± 0.74 (sd) eggs and the mean distance between nests was 2.74 ± 1.01 meters. Nesting occurred in places with vegetation cover
    of about 40% and at a mean distance of 7.24 ± 2.31 m to water edge. Nests often were built among vegetation, but some occurred on dry
    mud (25%). Hatching success was 23% and mean net productivity was 0.33 ± 0.19 chicks per nest. The mass of hatchlings was 21.5 ±
    3.2 g at the frst day. Whole nest failure from human predation and sheep grazing was responsible for most egg losses. About 75% of the
    nests failed, being destroyed before hatching. Some conservation measures for this breeding colony are discussed.

  5. Plasma levels of Androgen, Progesterone and gonadal development of breeders and helpers in the Jungle Babbler Turdoides striatus

    Bharucha B., Padate G.

    Abstract     Read Article       Download
    23 70

    We examined the proximate causes of delayed breeding and helping (allo-parental) behaviour by measuring plasma testosterone and progesterone concentrations in female breeders, male breeders, and helpers in co-operatively breeding Jungle Babblers. No signifcant difference was noted in the body and gonadal weight of breeders and helpers females. Also testosterone levels in the blood plasma did not change signifcantly between breeding duo and helpers. This could be related to the fact that the reproductive activities (maintaining the territory, defending the nest etc.) are performed by all members of the flock. The progesterone levels and the size of oviduct
    were comparatively higher in breeding than in non-breeding females. In helper females, the level of this hormone was intermediate. This
    result suggests that helpers share all breeding activities (including parental, allo-parental behaviour) but subdued oviducal development
    prevents them from egg formation and egg laying.

  6. L’alimentazione della garzetta Egretta garzettae dell’airone bianco maggiore Ardea albanella Valle Canal Novo di Marano Lagunare (Udine)

    Privileggi N., Colla A., Vicario G.

    Abstract     Read Article       Download
    21 620

    Food of the Little Egret Egretta garzetta and of the Great Egret Ardea alba in the Valle Canal Novo (Marano Lagoon, Udine,
    Italy). The pellets of the great egret Ardea alba and the little egret Egretta garzetta collected in the Marano Lagoon (Udine, Italy) have
    been studied during a two year period, 2002 and 2004. 654 pellets, collected monthly at the roosts, have been analysed to gather information about the diet of these birds. This study shows an abundant and almost constant presence of remains of invertebrates, expecially
    insects and other arthropods. Many of them have been identifed up to generic, and sometimes to specifc level with the help of materials preserved on the Museo di Storia Naturale di Trieste. The great egrets capture mainly micromammals and insects, but also fshes and
    Polichaeta, instead of the little egrets that feed with a great variety of prey, insects, fshes, Polychaeta, crustaceans, molluscs, arachnids
    and micromammals. Some pellets made just by macroinvertebrates testify that the great egrets like best these kind of prey, when they are
    plentiful. The larvae and the adults of big dragonflies, Notonecta and also ground insects, digger insects like Gryllotalpa and cicada’s larvae represent an important component of the diet of the little egrets and contribute also to the diet of the great egrets. The more consistent chitinous fragments were still in a good condition but, because of their resistance to digestive processes, we can suppose a capture by
    amphibians or fshes plundered in their turn by the birds studied. This study gives detailed informations about the number of the taxa of
    entomological and ichthiological interest and consequently about environmental diversity.

  7. Gli uccelli acquatici svernanti nella laguna di Venezia nel periodo 1993-2007: analisi delle dinamiche temporali e spaziali

    Scarton F., Bon M.

    Abstract     Read Article       Download
    24 96

    Waterbirds wintering in the lagoon of Venice (Italy), 1993 – 2007, trends and spatial distribution. The waterbirds wintering
    in the lagoon of Venice increased from 74,462 birds (1993) to 201,717 (2007), counted during mean winter counts that encompassed
    the whole lagoon (about 55,000 ha in surface area). The peak value was attained in 2005 (214,640 birds), and the 2003-2007 mean was
    195,672 birds, which makes the lagoon of Venice the most important wintering area in Italy and one of the most important in the whole
    Mediterranean. Ducks were the majority, recently 53% of the total waterbirds; gulls (17%), waders (14%) and coots (13%) were the other most important groups. Over the last fve years, about 80% of the birds were counted inside fsh farms, which span over 9,500 ha, and
    20% in the open lagoon, with negligible percentages along the littoral strip. Inside fsh farms, where hunting occurs, density as high as 48
    birds/ha was reached during daytime. Over the whole lagoon, waders reached a density of 4.5 birds/ha of tidal flats (dunlin 3.8/ha; curlew
    0.3/ha; avocet 0.2/ha). From 1993 to 2007 and also from 1998 to 2007, most species showed stable or increasing trends, with only eight
    species, grebes and Red-breasted Merganser in particular, decreasing. Ducks showed a spectacular increase, with more than 100,000 birds
    gained in 15 years; most of these were Teals (+ 44,433 birds) and Mallards (+ 38,492 birds). Similar trends, even if less pronounced, were
    observed for three other northern Adriatic wetlands. On the other hand, in the rest of the Mediterranean many species did not show trends
    comparable to those observed in the Venice lagoon.

  8. Gregarismo e siti di alimentazione di Paridae e Aegithalidae svernanti nella pianura dell’Oltrepò Pavese

    Ferlini F.

    Abstract     Read Article       Download
    28 75

    Gregarious behaviour and feeding sites of Paridae and Aegithalidae wintering in Oltrepò Pavese plan. I have collected data
    on foraging niches of Great Tit Parus major, Blue Tit Cyanistes caeruleus and Long-tailed Tit Aegithalos caudatus in a deciduous woodland area in Oltrepò Pavese (Lombardy, N Italy) in winter 2006-2007. All species showed a high propensity to flock. The mean flock size
    was 6.1 birds. Unlike Long-tailed Tit, Great Tit and Blue Tit were more abundant in monospecifc flocks than in heterospecifc ones. The
    groups containing Blue Tits were less compact than others. The space distribution of the three species during feeding differs signifcantly. In monospecifc groups Great Tit showed a strong tendency to forage mainly on the ground. Blue Tit and Long-tailed Tit have always
    privileged the trees as feeding substrate.

  9. Song thrush Turdus philomelos winter diet in Mediterranean habitats: a case study in Greece

    Paralikidis N., Papageorgiou N., Tsiompanoudis A., Kontsiotis V.

    Abstract     Read Article       Download
    25 138

    Dieta invernale del tordo bottaccio Turdus philomelos in habitat mediterraneo: un caso di studio in Grecia. Il lavoro
    riguarda l’alimentazione del tordo bottaccio in ambiente mediterraneo, basandosi su dati raccolti in Grecia. La forte diversità floristica degli ambienti fornisce grandi opportunità alimentari per i
    numerosi tordi che giungono a metà autunno e svernano in Grecia.
    In questo periodo i tordi sono generalmente frugivori, mostrando
    forte preferenza per i frutti coltivati. Le informazioni sulla dieta
    sono state raccolte in due aree di studio in Grecia centrale. Durante la stagione venatoria i tordi sembrano preferire effettivamente i
    frutti, ma si nutrono anche di insetti Le olive sono la principale risorsa trofca del tordo bottaccio durante l’inverno. I nostri risultati
    mostrano la capacità del tordo di adattarsi ad habitat antropogeni.

  10. First winter observation of the Pallid harrier Circus macrourus in the Marche region, central Italy

    Morelli F., Giuliani A., Benedetti Y.

    Abstract     Read Article       Download
    28 70

    Vengono riportate due osservazioni invernali di albanella pallida nelle Marche (31 gennaio e 25 febbraio 2009), riguardanti entrambe maschi adulti, osservati in ambienti agricoli.
    Si tratta delle prime osservazioni invernali della specie per questa
    regione, e tra quelle a più elevata latitudine note per l’Italia. Gli
    autori inquadrano le osservazioni nel contesto corologico dello
    svernamento della specie, a scala nazionale e globale.

  11. Primi dati della comunità ornitica nidificante in tre foreste regionali del Parco Naturale dell’Aveto (Genova)

    Baghino L.

    Abstract     Read Article       Download
    27 78

    First data on the bird community living in three Re
    gional Forests of the Aveto Natural Park (East Ligurian Apen nines). During the 2007 breeding season, a sampling scheme us- ing
    a point-count method in the Zatta, Lame and Penna regional forests, has resulted in 482 birds belonging to 26 species. Abies forests give lower numbers in species richness, whilst higher values of
    both richness and diversity are recorded along the ridge meadows.
    Factors influencing bird community probably respond mainly to
    tree structure (strong proximity between individual trees, paucity
    of natural gaps and scrub vegetation), but north exposition of these mountain forests seems also play a role.

  12. Commissione Ornitologica Italiana (COI) - Report 22

    Janni O., Fracasso G.

    Abstract     Read Article       Download
    30 83
  13. Resoconto Ornitologico Italiano - anno 2007

    Sighele M., Janni O.

    Abstract     Read Article       Download
    30 68
  14. Recensioni - Book reviews

    Abstract     Read Article       Download
    26 50
  15. NEWS - Ornitho.it

    Lardelli R.

    Abstract     Read Article       Download
    26 105