Seasonal changes in nectar‐feeding by birds at zaria, nigeria

Nectar‐feeding of birds was recorded during a phenological study of the woody vegetation at Zaria in the Northern Guinea Savanna of Nigeria. Throughout the dry season when it is in a non‐breeding state, the Scarlet‐breasted Sunbird Nectarinia senegalensis concentrates on the ornithophilous plants which flower in an overlapping sequence, and exploits the smaller‐flowered species less frequently. As the flowering of the ornithophilous species decreases at the end of the dry season, the range of other plants exploited increases but, in the early rains as the flowering of the indigenous plants tails off, the sunbird switches to ornamental exotics and the indigenous, shrubby parasite, Tapinanthus globiferus. The bird is more conspicuously insectivorous during the wet season when it breeds. The Pygmy Sunbird Anthreptes platura is a breeding, dry‐season visitor which exploits a somewhat different range of small‐flowered, mainly entomophilous species and some exotics but also takes nectar from those ornithophilous species it can exploit, as well as the chiropterophilous Parkia clappertoniana. The bulk of the breeding population leaves the district before the flowering of the indigenous plant tails off. The five other species of sunbird recorded in the district are either very rare residents or more numerous wet‐season visitors and passage migrants for which records of nectar‐feeding are too few to draw conclusions about seasonal changes but the wet‐season visitors appear to rely on the garden exotics in the comparative absence of flowering indigenous plants. Nectar‐feeding on Bombax costatum and Parkia clappertoniana, where nectar is readily accessible and present in relatively large quantities, was noted for IS species of non‐nectariniid birds, some of which were regular visitors. Some examples of flower consumption probably related to nectar‐feeding are also mentioned.