Resumen

The survey was conducted in two test areas in Wólka Kątna and Zemborzyce in Eastern Poland in winter 2012/2013. The winter diet of Long-eared Owl Asio otus in the test areas differed significantly. In Zemborzyce the Levins food niche breadth index and the Wiener-Shannon biodiversity index were strongly correlated with the average temperature and the snow depth, and not correlated with the precipitation. In Wólka Kątna no correlation was found. No correlation between the weather factors and the number of each prey species was found, except the Tundra Vole Microtus oeconomus in Zemborzyce, which occurrence in owls’ pellets was positively correlated with the temperature and negatively correlated with the snow depth. Seven factors describing the owls’ diet was chosen: average number of prey in one pellet, average number of prey per bird per day, share of Arvicolidae and Muridae in prey number and prey biomass, and the biomass of prey per bird per day. The share of Arvicolidae in biomass negatively correlated with the precipitation on the Zemborzyce test area and no other dependency between diet factors and weather conditions was found.

Palabras clave: Long-eared Owl winter diet Asio otus weather.

2018-10-24   |   192 visitas   |   Evalua este artículo 0 valoraciones

Vol. 6 Núm.1. Enero 2014 Pags. 103-108 Ecologia Balkanica 2014; 6(1)