Inter-specific and intra-specific interactions among birds feeding on nectar in Malta : winter and spring 1978

Abstract

Observations of interactions among various species of birds which were feeding on nectar of Antholyza aethiopica and Prunus domestica italica revealed the following interspecific "peck order" among the avian nectarivores. High ranking birds evicted lower ranking ones from nectar sources: (1) male Blackcap Sylvia atricapilla; (2) Sardinian Warbler Sylvia melanocephala and Subalpine Warbler Sylvia cantillans; (3) female Blackcap and Chiffchaff Phylloscopus collybita. Sardinian Warblers are resident all the year round, while the Chiffchaffs were probably all winter residents. One of the Blackcaps was a winter resident while most of the rest were probably spring passage migrants. The Subalpine Warbler is a spring passage migrant and does not breed locally. Chiffchaffs employed hovering as a means of extracting nectar rapidly from the flowers, before they could be evicted by the other birds. They were also observed hovering in order to probe flowers which could not be probed easily by climbing the peduncle. When Chiffchaffs could feed at flowers undisturbed, they generally climbed the peduncle, hovering relatively infrequently only when flowers were in an awkward position.