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The diet of the Common Barn-owl in a forest- and shrub-dominated hunting area in the Strandzha Mountains, southern Bulgaria, was identified from 516 prey specimens. Shrews (52.9% by number, 26.7% by biomass) and rodents (42.1% N, 71.5% B) were prevalent. Among them, White-toothed shrews, Criocidura sp., (45.3% N, 21.4% B) was the most numerous prey genus. Mice, Apodemus sp., (15.7% N, 29% B) contributed with the largest share to the food biomass due to high predation of Striped field mice, A. agrarius, (12.2% B). The proportions of forest species in diet (Apodemus sp, Sorex sp., and dormice liridae) increased with the higher proportion of forest habitats (forests and shrublands cover more than 25% of the area) in most Barn Owl hunting territories in southern Bulgaria.

Three species of Bush-crickets (Orthoptera) of conservation value or poorly known were found in the Eurasian Eagle Owl food in southeastern Bulgaria. Their localities are new country records and two of them cover Natura 2000 SCI zones. The repeated predation on Bradyporus macrogaster in UTM square MG99 confirms the potential of this area for a new Natura 2000 site.

A study of the diet of the Great Cormorant Phalacrocorax carbo sinensis (fish species and size) in (1) different seasons (years), (2) breeding stages (incubation and chick rearing), and (3) breeding areas (center and edge) in the colony in the Dzierżno-Duże Reservoir (southern Poland) was carried out. Overall, 147 pellets of the Great Cormorant were analysed. The low values of the indexes of Levin (Bi) and Shannon (H’) showed a limited trophic spectrum in the diet of the Great Cormorant. Roach (Rutilus rutilus) with a percentage index of relative importance (%IRI) of 62.89, perch (Perca fluviatilis) (%IRI = 22.63) and carp (Cyprinus carpio) (%IRI = 10.43), were the most common prey. Evident changes in the diet between 2003 and 2014, with less roach and more perch and ruffe in 2014 were found. They could be probably related to changes in the fish community. Differences in the food of cormorants between breeding stages reflected dietary requirements of the chicks. During the breeding season younger chicks require feeding with smaller fish than older chicks. The proportion of fish species found in the cormorant diet differed between the edge and the centre of the colony. We concluded that the impact of Great Cormorants on native fish assemblages may be dependent on the location within the colony, development state of the chicks and season, not just fish availability.

This study investigated the dietary niche of the Barn Owl(Tyto alba)in an intensively farmed landscape, based on pellet samples from 12 nesting pairs containing 25 animal taxa and 1,994 prey items after the breeding season in 2016. Based on land use categories of the buffer area around each nest, three landscape types (agricultural, mosaic, urban) were considered, to analyse the diet composition and food-niche parameters. Niche breadth was calculated at the local and landscape level. Small mammals were the most frequent in the diet than other prey in each of the landscape types. The Common Vole(Microtus arvalis), considered to be an important agricultural pest was the most numerous prey in all landscape groups. The trophic niche of Barn Owl varied between 0.69 – 0.86 at the local level, and the overall value of niche breadth was significantly higher in the urban than in the other two landscape types. Our results showed that the increase of Common Vole frequency lead to a decrease in niche breadth; significantly negative relationship was detected between these parameters. Despite differences in niche breadth, similarly high niche overlaps were detected by the randomisation test in the three landscapes. Our results suggest that the diet composition of Barn Owls, mainly their food-niche pattern, reflected prey availability in the comparison of the studied landscapes, which pointed out that it is necessary to examine the dietary difference of Barn Owls at the finer scale of land use.

The feeding of Little Owl (Athene noctua) was studied in a farmland area of Kiskunság, Central Hungary. For the analyses, a total of 661 Little Owl pellets were collected between February and September 2005 from three locations, corresponding known Little Owl territories situated nearby the settlements Apaj, Kunpeszér and Ladánybene. The aim of the present study was to explore the diet composition of Little Owl and to give a detailed evaluation of the arthropod diversity based on the pellet analysis. The identified prey items represented 15 vertebrate and 39 invertebrate species/taxa. In terms of prey number, dominance of small mammals was observed in two sites (Apaj – 55%, Kunpeszér – 68%), while birds and mammals shared almost equal dominance (~25%) in Ladánybene. The most numerous mammal species was the Common Vole (Microtus arvalis), while the Starling (Sturnus vulgaris) played key role among the birds. Contribution of amphibian Common Spadefoot (Pelobates fuscus) was considerable, while share of reptiles was marginal. Vertebrates also played a predominant role by contributing over 99% of the overall prey biomass in all study sites. Invertebrate prey dominance ranged from 24.8–30.0% while their contribution to the overall biomass was very low (0.14–0.34%). Large sized beetles (Pentodon idiota, Melolontha hippocastani) and orthopterans (Tettigonia viridissima, Gryllotalpa gryllotalpa) were preferred. Arthropod species richness and diversity were the highest in Kunpeszér, supposedly owing to the rich mosaic habitat structure.

Three cases of carrion-feeding with remains of artiodactyls (0.3%, n=1104 samples with food remains) have been documented in a long term diet study of Eurasian Eagle-owls (Bubo bubo) in 53 localities at Southeastern Bulgaria. Bone pieces of a sheep/goat (Ovis aries/Carpa hircus), a Fallow Deer (Dama dama) and a Domestic Pig (Sus scrofa dom.) in three Eurasian Eagle-owl breeding localities (5.7%) prove extremely rare feeding on carrion. Northern White-breasted Hedgehog (Erinaceus roumanicus), rats (Rattus sp.), waterbirds and gallinaceous birds (total 59.5-72.6% by biomass) constituted the main portion of the diets with carrion remains. The comparisons between food niche breadths, diet composition, average prey biomass and values of superpredation of the annual diets in the three localities have not supported the carrion-feeding of the Eurasian Eagle-owl as a result of food shortages.

Background and purpose: The assumption that the species composition and the relative abundance of small mammals in pellets of Barn Owls reflects the landscape structure of the hunting area is tested, based on habitat preferences of small mammals identified from pellets collected in the hilly and lowland parts of Baranja county (Croatia). Materials and methods: During 2007 we collected 2395 whole pellets and their fragments in 21 localities, from which 6613 prey remains were identified as belonging to small mammals (99.5%) of 23 species. The correlation between the relative abundance of mammal species and landscape structures (habitat types and landscape features) was tested. Results: There was a significant correlation between the relative abundance of seven small mammal species and the proportion of particular landscape structure classes. The number of small mammal species showed a negative correlation with the area of inland marshes. The evenness of the small mammal fauna grew with the mosaicity of landscape and the length of the borders in the owl’s hunting area. In the total prey the Common Vole (Microtus arvalis) dominated with more than 62%, which indicates its population outbreak. The diversity and evenness of small mammals in the hilly and lowland regions did not differ. Conclusions: We found significant correlations between the relative abundance of some small mammal species and the landscape structure classes in the owls’ hunting area. Our results suggested that the diversity of small mammals increases as the mosaic of the landscape increases, while the degree of population outbreak of the Common Vole decreases. These relationships should be taken into consideration when designing landscapes or changing land use.

We examined changes in diet composition during the breeding period for the endangered Lesser Kestrel (Falco naumanni). Pellets were collected weekly from the last week of March until the first week of July in a colony located in southwestern Spain. Diet composition was evaluated in terms of frequency of occurrence of different prey, mean prey weight, and prey richness of each pellet. Generalized additive models were used to analyze the predictive ability of calendar week (as an index to prey availabil- ity), reproductive week (as an index to breeding demands), and nest identity (as a proxy for individual preferences/abilities) on the above dietary metrics. Primary prey species were the mole cricket (Gryllotalpa gryllotalpa) during courtship, the saddle-backed bush cricket (Ephippiger ephippiger) during incubation, and the migratory locust (Locusta migratoria) and the white-faced bush-cricket (Decticus albifrons) during the nestling phase. Small mammals were only important during some particular weeks at the beginning of the nestling period. Mean prey weight increased as the breeding season advanced, while species richness tended to decline. This was mainly due to the decreasing contribution of small prey items such as beetles to the diet and the greater incidence of large prey species. Calendar week and reproductive week had similar abilities to predict diet composition, and were better predictors than nest identity. Models fitted to particular prey species had greater explanatory power than models fitted to prey groups. Likewise, models fitted to those prey species that we considered ‘‘preferred’’ fitted better than those considered ‘‘refuge’’ prey.

The analysis of 1109 pellets collected between 1992 and 1994 in 2 localities of Northern Algeria : El-Harrach near Algiers (n = 615 pellets) and Boukhalfa near Tizi Ouzou (n = 494), brings some preliminary information on the diet of the north African subspecies of Tawny Owl (Strix aluco mauritanica). The breakdown of the 3694 identified prey is as follows : 3150 vertebrates (85.3 %) and 544 invertebrates (14.7 %). Among the vertebrates, mammals formed 43.6 % of the prey, birds 29.3 %, amphibians 15.2 % and reptiles 11.8 %. Insects are often captu¬ red but are of little importance in terms of biomass ; they are dominated by Orthoptera (44.1 %) and Coleoptera (35.7 %). The Tawny Owl’s diet is different in the 2 sites. At El-Harrach, a sub-urban area, the diet includes a large proportion of birds and synanthropic mammals (mice, rats) and a large number of a reptile Tarentola mauritanica. At Boukhalfa, a cultivated country area, mammals are more widely represented with a greater diversity of species, and rodents form the main prey. We can notice an important proportion of amphibians in both areas. Preliminary results are given on seasonal variation at Boukhalfa and a comparison is done with the diet composition of the Bam Owl Tyto alba at El-Harrach. Mice represent the owls’ basic prey in all the countries south of the Mediterranean sea. The originality of the Algerian analysis lies in the predominance of Mus musculus in comparison with Mus spretus., L'analyse de 1109 pelotes de réjection de Chouette hulotte (Strix aluco mauritanica) récoltées de 1992 à 1994 dans 2 sites du nord de l'Algérie (El-Harrach près d'Alger et Boukhalfa près de Tizi-Ouzou), apporte les premières informations sur le régime alimentaire de la sous-espèce maghrébine de Chouette hulotte. Les 3694 proies identifiées comprennent 3150 vertébrés et 544 invertébrés. Parmi les vertébrés on trouve 43,6 % de mammifères, 29,3 % d'oiseaux, 15,2 % d'amphibiens et 11,8 % de reptiles. La prédation d’invertébrés, uniquement des insectes, en majeure partie des Orthoptères (44,1 %) et des Coléoptères (35,7 %), est notable mais leur biomasse est négligeable. Le régime alimentaire de la Chouette hulotte diffère dans les 2 sites. A El-Harrach, en milieu sub-urbain, il comporte une forte proportion d'oiseaux et de mammifères anthropophiles (souris, rat) ainsi qu’un nombre non négligeable d’un reptile Tarentola mauritanica. A Boukhalfa, en milieu agricole, les mammifères, surtout des rongeurs, dominent très nettement. Dans les deux milieux, la proportion importante d’amphibiens est à noter. Une première approche des variations saisonnières du régime est présentée pour le site de Boukhalfa et une comparaison avec le régime de la Chouette effraie Tyto alba est faite à El-Harrach. La forte consommation de souris est un trait commun des pays du sud de la Méditerranée. L’originalité des sites algériens réside dans la prédominance de Mus musculus par rapport à Mus spretus., Hamdine Watik, Boukhemza Mohamed, Doumandji Salaheddine, Poitevin Françoise, Thevenot Michel. Premières données sur le régime alimentaire de la Chouette hulotte (Strix aluco mauritanica) en Algérie. In: Ecologia mediterranea, tome 25 n°1, 1999. pp. 111-123.