Investigation of roadkilled Western Barn Owls (Tyto alba) in Csanádi-hát region (SE Hungary)

Abstract

The Western Barn Owl (Tyto alba) is a common breeder in Hungary. It is a resident bird of open areas, staying near nesting sites in winter. Its population is strongly influenced by food availability, weather conditions and several anthropogenic activities. One of the most important factors of these in recent decades has been road mortality. In this work, we processed data of roadkilled individuals and field observation records in the Csanádihát region in south-eastern Hungary from the period 1995–2022. In Battonya, we have been recording roadkill individuals since 1995, while observations of Barn Owl individuals from Kevermes have been available since 2005. The species is a regular, but scarce breeder in the area, so both the number of roadkilled individuals and the number of field observations were relatively low. Nevertheless, we had the opportunity to examine how the number of individuals of the species that were killed in the traffic varied over time and within years. According to our data, more birds collided during the winter, and also between July and November. This can be explained mostly by the seasonal lack of food and the fledging time of inexperienced juveniles. The temporal distribution of field observations were different from the dynamics of the roadkills, as the species was mainly observed during the breeding season. The exact population size of the area can be difficultly estimated, as it breeds mainly in attics of stable, granary and church buildings. The breeding population of Kevermes was estimated at 3–4 pairs and did not change significantly in the studied period. Over the same 28-year period, using the same methods to the two other most common nesting owl species of the region, we found that the within-year roadkill dynamics of the Little Owl (Athene noctua) and the Northern Long-eared Owl (Asio otus) differed from that of the Western Barn Owls, which may be due to the different feeding habits of the species. We can conclude that the number of roadkilled birds was proportional to the local population of the species.