Diet of Blackbird nestlings in orange groves: seasonal and age-related variation.

Full article

Published:

Volume 40(2), December 1993. Pages 113-119.

Language:

English

Keywords:

Blackbird, diet diversity, eastern Spain, nestling diet, orange groves, Turdus merula.

Abstract:

The study was carried out in an extensive orange monoculture in easten Spain, using the neck-collar method. Lumbricidae, snails of the genus Helix and Peridroma saucia (Lepidoptera, Noctuidae) were the most abundant prey in the diet of nestling Blackbirds (Turdus merula). P. saucia was consumed as caterpillars, pupae or imagines. Secondary prey included Dermaptera, Orthoptera, Coleoptera, Hemiptera, Formicidae, Miriapoda, Araneidae and fragments of oranges as plant food. The diet was more diverse in April than in May and June, due to quantitative changes in the prey types consumed. The diet of the nestlings was more diverse in old nestlings (9-12 days) than in young (2-4 days) or middle-aged (5-8 days) ones. This was caused by a decrease in the proportion of earthworms and an increase of Lepidoptera and secondary prey late in the nestling period.