Ornis Hungarica. vol.1. (1991) p.10-28.
Guild structure and seasonal changes in foraging behaviour of birds in a Central-European oak forest
Foraging behaviour of IO resident and 4 migratory species was studied throughout a year in an oak forest of the Bükk Mts., North-Hungary. The resident species could be grouped into two guilds by Principal Component Analysis. Tits (Parus major, P. caeruleus, P. palustris), Long-tailed Tit (Aegithalos caudatus) and Goldcrest (Regulus regulus) were included in the foliage-gleaning guild, while woodpeckers (Dendrocopos major, D. medius, D. minor), Nuthatch (Sitta europaea) and Treecreeper (Certhia sp.) formed the bark-foraging guild. Chiff-chaff (Phylloscopus collybita), Wood Warbler (P. sibilatrix) and both species of flycatchers (Muscicapa striate and Ficedula albicollis) were not separated from the resident species as flycatcher guild, instead they were included in the foliage-gleaning guild.