Volume 48
2024


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Volume 48 continuous publishing



  1. Editorial - The pitfalls and potential of citizen science in ornithology

    Arianna Passarotto & Alessandra Costanzo

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    234 264
  2. The humble Stonechat Saxicola rubicola and the species neglected by ornithological research in Italy

    Maurizio Sarà

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    198 266

    The query of one of the major online scientific research databases returned quite worrying data, because a large group of species breeding in Italy, 47 out of 270 (17%) has never been studied and this number grows further (56 species, 20.7% of the total) if we consider that 9 species with published papers have 0 h-index (i.e. do not yet have any citations). These species neglected by Italian ornithological research have been called ‘zero species’. Bird species without indexed studies are 87.2% native and mostly migratory (66.0%). They live mainly in wetlands (36.2%) and forest habitats (27.7%) and generally have an increasing population trend (44.7%). Furthermore, the majority of these species are classified as least concern by the Italian Red List (44.7%), with a lower percentage of threatened species (34.0%). Zero species are more unprotected than protected ones (61.7% vs 38.3%). Finally, 42.6% of them belong to passerines and have a very restricted geographical range (83.0%). Some examples of zero species are reported and discussed, such as the Stonechat Saxicola rubicola, the Common redpoll Acanthis flammea or the Red Kite Milvus milvus, highlighting some of their interesting traits that could stimulate research aimed at conservation.

  3. Territory selection of breeding Golden Eagles Aquila chrysaetos in a low-density population

    Andrea Mazzarano, Riccardo Mattea, Gianluca Damiani

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    180 221

    Territory selection by birds of prey is an essential process influencing survival and productivity. For Golden Eagle Aquila chrysaetos, research in Europe has focused primarily upon migrating and high-density populations, and rarely on the territory selection in low-density populations. We analysed Golden Eagle breeding sites in Central Apennines (Italy), spanning from 29 sites in 1980 up to 38 sites in 2020, verifying in 4 different years (1980, 1990, 2000 and 2020) their status of occupancy or vacancy, through cross-checking data from available literature and field observations. In the chosen years, each site was characterized by land use and neighbouring distances variables, to individuate the presence of a possible common selection process. The different protection status of each area (unprotected or Natural/National Parks) was tested, assuming that habitat protection could have positive effects on Eagles’ territory selection. The so obtained panel data was statistically analysed by means of t-test, χ2 test and probit models. In one hand, Golden Eagles in the Apennines showed a continuous recolonization of territories, including seven previously vacant and two undiscovered sites. On the other hand, half of the vacant sites remain unoccupied. Our results suggest that Golden Eagles, in a low-density population, tend to minimize the effect of lower quality habitats by choosing a breeding territory which can guarantee low intra-specific interferences: 35% of 2020 breeding pairs have, at least, one nearby vacant territory. Depending on the quality of the available breeding habitat, Individual Adjustment Hypothesis (IAH) supports or replaces Habitat Heterogeneity Hypothesis (HHH).

  4. Diet of Golden Eagle (Aquila chrysaethos) nestlings in Central Apennines, Italy

    Gianluca Damiani, Andrea Mazzarano, Silvia Dancali, Paolo Forconi

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    67 96

    The diet of animal species reflects important evolutionary and behavioural adaptations that may affect the viability of populations. The reproductive success, the habitat selection, and the spatial distribution of individuals are often related to trophic resources. By studying the diet of a predator, it is possible to better understand the ecological interactions between different species at a local scale. We studied the nestlings’ diet of six Golden Eagle (Aquila chrysaetos) breeding pairs in Central Apennines (Italy), through the analysis of pellets and prey remains (2000-2004) and integrated them with visual observations (2000-2022). While data from pellets and prey remains allowed for estimates in biomass and diet breadth, nest visual observations provided new qualitative insights into the species’ hunting behaviour. We were able to identify 16 species of mammals, 14 species of birds and 2 species of reptiles among prey items. The application of the Levins index on the 21 families detected produced a value of 8.45, indicating a rather wide trophic niche. The dominant preys were hares (Lepus europaeus and Lepus corsicanus), with a 25% frequency and 43% of the total estimated biomass. Notably, it appears that wild boars and corvids are becoming more important for the diet of the golden eagle’s nestlings, which is in agreement with the recent expansion of such species in the study regions, coupled with the decline of hares and Phasianids.

  5. Moult strategies and morphometric precisions in the Lilford's woodpecker Dendrocopos leucotos lilfordi

    Patrice Urbina-Tobias, Jean-Louis Grangé

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    58 75

    This article presents a study of the plumage of the Lilford’s woodpecker Dendrocopos leucotos lilfordi. The species performs a partial post-juvenile moult for the first-year birds and a complete post-nuptial moult regularly arrested for adults. The criteria presented make it possible to differentiate the two age-classes of a bird in hand. Furthermore, a difference in wing shape via the wing formula appears between females and males, suggesting a different internuptial or post-juvenile dispersal behaviour depending on the sexes.

  6. Occurrence of Laminosioptes cysticola (Acariformes: Laminosioptidae) in Ardea alba egretta from the peri-urban area of Belém, Pará-Brazil

    David F. Conga, Gerson B. Oliveira, Amanda A. Figueiredo, Ana Sílvia S. Ribeiro, Washington L.A. Pereira

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    64 78

    Mites of the genus Laminosioptes have been reported in domestic Galliformes birds and pigeons in some countries. They specifically infest the subcutaneous tissue of the host generating granulomatous lesions. In the current study, we reported the presence of Laminosioptes cysticola in the pectoral muscle of a specimen of Great Egret, Ardea alba egretta, found in the peri-urban area of Belém, Pará, Brazil. We discuss the role of this individual as vector of mites between domestic and wild birds and we recommend ornithologists and veterinaries to carry out careful observations of live and dead birds because small parasites such as the mites L. cysticola can easily remain undetected.

  7. The State of Sombre Tit Poecile lugubris Temminck, 1820 in Armenia

    Karen Aghababyan, Gurgen Khanamirian, Viktorya Gevorgyan, Asya Ghazaryan

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    42 72

    The Sombre Tit Poecile lugubris is very little studied species, and within Armenia, it occurs only in the south-eastern regions of the country. The current study aims at providing data for the next assessment of the conservation status of Sombre Tit in Armenia, based on the data collected from 2003-2019. The obtained data show that Sombre Tits have slightly expanded their distribution to the north; their current Area of Occupancy makes 94 km2, while the Extent of Occurrence covers 1,065 km2. The population of Sombre Tit makes from 910 to 1,350 breeding pairs. During observed 17 years (2003-2019), the population trend of the species computed for the Meghri region of Armenia can be considered stable (Imputed Overall Slope: Additive = 0.0017 ± 0.0109; Multiplicative = 1.0017 ± 0.0109; P > 0.05), although demonstrates relatively strong fluctuations. The conservation status of Sombre Tit in Armenia should be revised, as it can correspond to the category Endangered, according to criteria C2a(ii). The main factors that can influence the species in Armenia are forest fires, which are relatively common in south-eastern Armenia, and the use of pesticides for forest pest control.

  8. Laying eggs on the same nest: unusual mixed-species clutch among three colonial shorebirds

    Paolo Salvador, Stefano Sponza

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    58 64

    Mixed clutches are relatively uncommon among colonial shorebirds and challenging to document. Here, we report the co-occurrence of three species’ eggs, belonging to Pied Avocet Recurvirostra avosetta, Little Tern Sternula albifrons and Common Tern Sterna hirundo, in the same nest within a large colony in the Marano and Grado Lagoon, Friuli Venezia Giulia. To our knowledge, it is the first record with more than two species among Charadriiformes. We discuss the possible explanation concerning the limited suitable nesting space in a human-made breeding habitat. These findings are rarely reported despite their importance for comprehending the phenomenon from an ecological perspective.

  9. Long-term population trends of bird communities in artificially-protected wetlands of Northern Italy

    Stefano Borghi, Carlo Giannella, Andrea Ravagnani, Rossella Casari, Alessio Farioli, Giuseppe Rossi, Matteo Dal Zotto, Nunzio Grattini, Daniela Campobello

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    63 110

    Artificial wetlands have become a common conservation approach to contrast the decline of biodiversity globally, as a result of the ongoing loss and fragmentation of natural habitats. Assessments on the trend of the avian biodiversity in artificial wetlands are essential to understand their conservation value. This study aims to analyse temporal changes in the abundance of bird guilds and species in small artificial wetlands in Northern Italy. We surveyed bird populations over the 2005-2019 period from three adjacent wetlands, and examined temporal trends of species as both single species and grouped in guilds. We found the water systems analysed supported a high diversity of species. Overall, we found Swans and Geese, Cormorants, Raptors and Large wading birds had an increasing trend between 2005 and 2019, while Gulls and Terns were stable, Ducks, Rails and Cranes, and Grebes and Divers were uncertain, and Shorebirds decreased. Species-specific trends were revealed: Circus cyaneus (+13.40%) and Falco vespertinus (+21.32%) increased, while Calidris pugnax decreased (-7.91%) and Aythya nyroca was uncertain (+6.30%). Furthermore, dominant species had mainly a stable abundance (e.g. Larus ridibundus and Anas platyrhynchos), while Anas crecca increased (+2.97%), Vanellus vanellus decreased (-3.65%), and Fulica atra had an uncertain trend. We described these local systems as of vital importance to sustain the local and regional avian biodiversity, also urging to ensure national and international functional connectivity between natural and artificial systems.

  10. New extra-Amazonian records of the Black-billed Cuckoo Coccyzus erythropthalmus (Cuculidae) for Brazil

    Fabio Schunck, Luis Katsumi Yabase, Marta Yabase, Guilherme Alves Serpa, Mateus Rocha Ribas, Pedro Scherer-Neto, Gérard Baudet, Eduardo Carrano, Tomas Sigrist, Guilherme Renzo Rocha Brito

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    44 67

    The breeding grounds of the Black-billed Cuckoo Coccyzus erythropthalmus encompass a wide area in northern North America. During the austral winter individuals migrate to non-breeding areas in South America. There had been only three known locations for the species in Brazil, two in the Amazon Forest and one in the Atlantic Forest. Here, we aim to present new records in Brazil and to organize the available literature recovering historical data. The new records are in the Southeast and South regions and thus represent the first documented records outside the Brazilian Amazon. These findings indicate an expansion of the area considered nomadic for the species. All extra-Amazonian records were made in strong El Niño years, a climate phenomenon that may be changing bird migration patterns in South America, which requires further investigation.

  11. To change not to drown: Eurasian Oystercatchers Haematopus ostralegus adopt pole tops as safe nesting sites in the Lagoon of Venice

    Roberto G. Valle, Francesco Scarton

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    48 74

    Eurasian Oystercatchers have increasingly adopted pole tops in the last decade in the Lagoon of Venice (NE Italy). At the end of the study, 7% of the breeding population of the Lagoon (n = 180) nested on pole tops. Nests built in these structures are safe from flooding due to extremely high tides, thus allowing a high hatching success: 42 clutches out of 43 (97.7%) hatched. We hypothesise that this is an adaptive behaviour to the increased frequency of extreme high tides in the last decade and is a good omen for the species. The good availability of pole tops suitable for nesting in the Lagoon allows breeding in areas otherwise unsuitable for nesting due to the lack of sites safe from flooding. Placement of artificial nests on pole tops is also feasible and could be an easy and cheap strategy for the conservation of the breeding population of Oystercatchers in the Lagoon of Venice as extreme high tides and spring storms will likely increase in the future