Original scientific paper
Diet of wintering Long-eared Owl Asio otus in Županjska Posavina
Alma Mikuška
orcid.org/0000-0002-4825-7089
; Sub-department of zoology, Department of Biology, Josip Juraj Strossmayer University of Osijek
Višnja Jovanovac
; Sub-department of zoology, Department of Biology, Josip Juraj Strossmayer University of Osijek
Tibor Mikuška
; Croatian Society for the Bird and Nature Protection
Abstract
The study presents the diet of the Long-eared Owl at wintering
roosts in rural areas of Strošinci, Drenovci, Bošnjaci and Županja in
Županjska Posavina. The total of 1,073 pellets were collected during the winter of 2014/2015; they contained remains of 2,473 specimens belonging to 13 species of small mammals and two bird species. The average number of prey per pellet was 2.36. The majority of small mammal species belonged to the Arvicolinae and Murinae subfamilies, with Common Vole Microtus arvalis being the most dominant species represented in the diet (76.1%). The food niche of the Long-eared Owl measured by standardised Levin’s index of niche breadth was the widest (0.07) in Strošinci, and the narrowest (0.02) in Bošnjaci. The Shannon–Wiener’s measure of diet niche breadth varied between 1.12 (Strošinci) and 0.58 (Bošnjaci). According to the Bray–Curtis index, the highest percentage overlap of prey composition (86.56%) was between Županja and Bošnjaci. Županjska Posavina was hit with catastrophic floods during
the summer of 2014. A comparison among flooded and not flooded areas showed no statistically significant difference in the prey composition of the wintering Long-eared Owl in studied areas.
Keywords
Hrčak ID:
153106
URI
Publication date:
18.2.2016.
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