The diet spectrum of the great tit (Parus major L., 1758) was studied in transformed forests of northeastern Ukraine. Four forest ecosystems were surveyed: four model sites in oak woodlands and in a pine–oak forest with different stages of recreational digression. Forty-seven taxa of invertebrates (n = 325) were detected in the ration of great tit chicks. Insecta (72.4%): Lepidoptera (seven families, 35.9%), Hymenoptera (two families, 21.0%), Diptera (seven families, 2.7%) and Coleoptera (four families, 1.8%) were among them. In terms of the qualitative composition of invertebrates (20 species, 42.6%) and the proportion of seized food objects (159 objects), phytophages prevailed. The food composition of great tit chicks was the most similar in territories MS1 and MS4. It contained six common taxa for these territories (Stugren–Radulescu Index = 0.7, Jaccard = 0.2, Sorensen = 0.3).
