Interactions between hooded crows (Сorvus cornix) and Eurasian magpies (Pica pica) and their nesting site preferences in anthropogenic landscapes

Abstract

ABSTRACT The interrelationships of many urban birds, especially the ones that influence other birds’ nesting populations, remain understudied. Hooded crows (Corvus cornix) and Eurasian magpies (Pica pica) are numerous in cities and are aggressive species whose habitats significantly overlap. The influence of habitat on the nesting preferences of magpies and hooded crows was studied in Poltava city (central Ukraine). Spatial and statistical tests were computed in order to analyze spatial patterns and distribution of both species, as well as the influence of crows’ presence on magpies’ nesting. Magpies preferred plots in private sectors, avoiding industrial and tall building areas, whereas the density of hooded crows was higher in parks and green spaces. The height of magpies’ nests appeared to be determined by tree height, but not by anthropogenic pressure. Crows were nesting only in high trees, which had an influence on their distribution in Poltava city. Spatial analysis of habitat preference demonstrated that magpies and crows prefer habitats dominated by lawns, roads, and other artificial surfaces, and avoid dense tree cover. Magpies avoided nesting near crow nesting sites, up to a distance of 700 m. Competition between magpies was not noticed, but rather a tendency toward aggregation of their nests.