Spanish sparrows dismembering flowers

Abstract

Over several years in late March to May, Spanish Sparrows Passer hispaniolensis have been watched dismembering the flowers of Orange trees (Citrus sinensis) in a private garden at Fleur de lys and at San Anton. The sparrow deliberately bites off part of the flower and chews the part in its bill. The bill movements used are similar to those used by sparrows to immobilise a large insect before swallowing it. The flower part, usually a petal or a group of stamens, is held transversely in the bill, which executes many sequential pressing movements on the flower part, as the latter gradually moves through the bill in a transverse plane. The flower parts are not swallowed, and are discarded immediately afterwards. It looks as though the sparrows are pressing the flower parts in order to extract and drink the cell sap which oozes from the pressed petals and stamens. Ilma iaghar, made by pressing orange blossoms, is a traditional Maltese medicinal drink, well known in Maltese domestic culture.