Occupation and breeding parameters in the Great Tit Parus major and the Italian Sparrow Passer italiae in nest-boxes of different size

Abstract

This study examined the preference for nest-boxes of two different dimensions (14x14x22 cm, hole diameter 3.7 cm, 'normal'; 25x25x35 cm, hole diameter 6 cm, 'large') for three breeding seasons in the Great Tit and the Italian Sparrow together with specific reproductive parameters. Sparrows showed a significant preference for normal boxes while tits seemed not to discriminate between large and normal boxes although in the large ones the breeding success was impaired by higher predation rates. For both species no differences between the two kinds of boxes were found for date of laying. As regards clutch size, data suggest that in large boxes tits laid larger clutches.