Trophic links of the song thrush (Turdus philomelos) in transformed forest ecosystems of North-Eastern Ukraine

Abstract

The diet spectrum of the song thrush (Turdus philomelos Brehm, 1831; Passeriformes, Turdidae) was studied with the aim of supporting the population of the species in transformed forests of North-Eastern Ukraine. Four forest ecosystems were surveyed: three model sites in oak woodlands with different stages of recreational digression, and the fourth model site in a pine-oak forest. A total of 45 invertebrate taxa with the dominance of Insecta (64.6%, n = 1321), Oligochaеta (16.7%), and Gastropoda (12.0%) were revealed in the diet of the song thrush. At the level of orders, Lepidoptera (66.2%) was dominant. In the qualitative structure of the song thrush nestling diet, the highest number of taxa (40.5–59.1%) was represented by phytophages. Phytophagous species also comprised the majority of the consumed prey items (44.7–80.3%). Environmental conditions are an important factor, affecting the diet composition of birds. The most favourable foraging conditions for the thrushes were revealed in natural protected areas. The analysis has shown a fairly even foraging efficiency of the thrushes in all the studied sites. The highest biodiversity indices were found in a protected area of the National Nature Park “Homilshanski Forests”. The results of the research indicate an important role of T. philomelos in the population management of potentially dangerous agricultural pests.