Maziarz M., Broughton R. K. 2015. Breeding microhabitat selection by Great Tits Parus major in a deciduous primeval forest (Białowieża National Park, Poland). Bird Study 62: 358-367.

Capsule Great Tits breeding in natural cavities in a primeval forest occupied microhabitats containing larger trees, but small differences between ‘breeding’ and ‘non-breeding’ locations indicated the minor importance of microhabitat selection in nest-placement decisions.

Aims We tested whether Great Tits breeding in primeval conditions used vegetation composition to choose breeding patches.

Methods Great Tit territories and nest-trees were mapped in two study areas in deciduous, old-growth forest. We compared tree species composition, tree girth and condition between ‘breeding’ and ‘nonbreeding’ plots.

Results Great Tit territories were tightly packed, filling most of the available area. Vegetation composition in ‘breeding’ and ‘non-breeding’ plots differed only for trees that could potentially harbour Great Tit nestcavities; ‘breeding’ plots contained larger trees. The distribution of Great Tit nests varied between years, with some ‘non-breeding’ patches in one year becoming ‘breeding’ ones in another.

Conclusion It seems unlikely that nest-placement decisions by Great Tits are constrained by the microhabitat quality under primeval conditions.