Alimentación de pichones de la paloma Zenaida auriculata

Abstract

During 1970, crop samples were taken from nestlings of the Eared Dove (Zenaida auriculata chysauchenia) in the eastern plains of Córdoba, Argentine Republic, where this dove has become a serious agricultural pest. Seeds and crop milk are the most important food items. No fruits or animal food were found. During the first days of the nestling’s life, crop milk plays an important role, which rapidly decreases afterwards (Fig. 1). The seeds of cultivated species are predominant, being mainly sorghum, millet, wheat, peanut, sunflower, and maize. Important weed seeds are Amaranthus spp. (Amaranthaceae), Chenopodium spp. (Chenopodiaceae), Argemone subfusiformis (Papaveraceae), Setaria pampeana, and Echinochloa colonum (Gramineae) (Table 1). Nestling crops have more small seeds and fewer medium and large-size seeds than the average adult crop content. Large seeds are absent during the first four days of life. Differences between adult and nestling food become less and less apparent as the nestling grows (Fig. 3). This means that availability of small seeds is necessary during the breeding period, or at least during the early part of the nestling’s life. Adults rearing chicks (as indicated by milk secretion) tend to feed on smaller food items (p < 0.01) than the rest. Nevertheless, large seeds are also found in their crops in smaller proportions. These data are consistent with the hypothesis that the greater proportion of smaller seeds in the nestling’s food is explained by both the deliberate choice by the parents and some sort of selection during the regurgitation of food from the adult to the chick.