Feeding ecology and diet

Other than that of a few larger species, such as the willie wagtail, the bill of fantails is not strong enough to handle large, robust prey. The major food is small insects and other invertebrates. Larger prey, such as moths, may be hammered on a branch to subdue and render it suitable to be eaten. The willie wagtail has captured and eaten small skinks. Most prey are caught in the air, gleaned from foliage, or, less often, pursued on the ground. The flight of a gray fantail for a flying insect can be an impressively dizzying aerial pursuit. Rapid loops and sudden changes of direction appear to threaten to break the bird apart. The tail is held cocked and spread as a

A gray fantail (Rhipidura albiscapa) at its nest. (Photo by R. Brown/ VIREO. Reproduced by permission.)

bird moves through the foliage, and it has been suggested that this may assist in flushing insects.

In a study of three coexisting Australian fantails, Elizabeth Cameron found that they partitioned the environment, each selecting different heights and sections of the substrate, and using different foraging techniques, thus reducing overlap and competition. During the summer, gray fantails fed across a broad range of elevations, occasionally in the canopy at heights of about 130 ft (40 m). The predominant foraging method was to search for prey from a lookout perch, then pursue it in the air, before returning to a new vantage point. Rufous fantails generally fed lower, in the understory and shrub strata, and spent more time actively moving through the foliage flushing insects. Willie wagtails remained within 10 ft (3 m) of the ground and often on it, either capturing prey in the air with short flights or pursuing it on foot on the ground. In winter, when the rufous fantails migrated away from the area, gray fantails became more aerial and willie wagtails more terrestrial.

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