Vol. 78 2026

ARTICLES

New Data on the Diet of the Tawny Owl Strix aluco (Aves: Strigiformes) from Bulgaria

Nedko Nedyalkov1,*, Zlatozar Boev1 & Ilcho Kolev2

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*,1National Museum of Natural History, Bulgarian Academy of Sciences, 1 Tsar Osvoboditel Blvd, 1000 Sofia, Bulgaria; E-mail: nnedko@gmail.com, zlatozarboev@gmail.com
2Studen Kladenets Str., Vh. №1, PO 1,7001 Russe, Bulgaria; E-mail:ilchokolev@abv.bg

https://doi.org/10.71424/azb78.3.003137

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Abstract

We present new data on the diet of the tawny owl (Strix aluco), collected from eight locations over the past 20 years. In total, 759 prey items of 77 taxa were identified, with small mammals comprising approximately 75% of the diet. Field mice (Apodemus spp.) were the most common mammalian prey, representing about 50 % (by frequency, out of 569 mammal items). The second most important prey group was dormice (family Gliridae), represented by three species (out of four found in Bulgaria): fat dormouse (Glis glis), forest dormouse (Dryomys nitedula) and common dormouse (Muscardinus avellanarius). Ten bat species were also identified among the prey, with bats being significantly predominant at a single site, which may indicate behavioural specialisation or targeted hunting of bats by the owl. Birds made up 18.97% of the diet, with 32 species identified. Amphibians and reptiles comprised 4.6% of the total prey. A significant shift was observed in the diet of the tawny owl in comparison to previous studies.

Key words

Bat predation, feeding biology, diet shift, small mammals, tawny owl

How to Cite
Nedyalkov N., Boev Z. & Kolev I. 2026. New Data on the Diet of the Tawny Owl Strix aluco (Aves: Strigiformes) from Bulgaria. Acta zoologica bulgarica 78.

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