Gleaning (birds) World flycatchers, Tyrant flycatchers, babblers, Old World warblers, New World warblers, Vireos and some hummingbirds and cuckoos. Many birds make use of multiple feeding strategies, depending on the availability of different sources of food and opportunities of the moment. Foliage gleaning, the strategy of gleaning over the leaves and branches of trees and shrubs, can involve a variety of styles and maneuvers. Some birds, such as the common chiffchaff of Eurasia and the Wilson's warbler of North America, feed actively and appear energetic. Some will even hover in the air near a leaf or twig while gleaning from it; this
Canary Islands chiffchaff and a longer tail. Its underparts have a brownish-buff tone, especially on the flanks and breast, and the upperparts are darker brown than the common chiffchaff. Many calls are similar to the common chiffchaff but the song lacks the metronomic quality of that species and is harsher, shorter and more varied and with a faster delivery. The Canary Islands chiffchaff occurs in most habitats from coastal gardens to high altitude vegetation but is absent from semi-desert scrub at lower altitudes. In the breeding period, January to June, the Canary Islands chiffchaff is territorial and is found singly or in pairs,