Feeding ecology and diet

All types of shrikes feed on a large variety of arthropods and are largely insectivorous. Small vertebrates and birds' eggs are also on the menu for the larger Malaconotus species and the true shrikes. At least some of the true shrikes occasionally indulge in small fruits and berries.

Bush-shrikes most often feed by gleaning the vegetation inside branches, trunks, and foliage, and have been compared to oversized warblers. Prey is taken at various forest levels according to the species. Some, like the rare Uluguru bush-shrike (Malaconotus alius), appear to be confined to the canopy; while others, like the gray-headed bush-shrike, forage at all levels. Where two related species come into contact, there might be an ecological segregation, and each shrike keeps to its preferred level. Some species, like the tchagras, some boubous, gonoleks, and the white-tailed shrike, pick much of their captures off the ground, where they hop about in the vegetation.

Helmet-shrikes search for food in noisy, sometimes mixed, groups. They may forage from ground to canopy, but seem to prefer middle or lower levels; at least some Prionops, when perched on a branch and looking for prey, tilt their heads on one side as if they were listening to their future victims.

True shrikes are "sit and wait" predators that spend a lot of time on a variety of perches. Prey is mainly caught on the ground, but in fair weather a lot of insects are hawked in the air. Impaling or wedging of prey is regular in Lanius, but has not been recorded in all species. It is regular in larger species like the northern shrike, which must anchor its small vertebrate victims in order to dismember and eat them. Impaled prey can serve as a larder available in bad weather, when insects are not very active. The habit of impaling for a few days may enable species like the loggerhead shrike to consume toxic prey once it has degraded. Impaling may also serve as mate attraction. The more prey that is impaled in a territory, the better the male may appear to a female, but this point needs further research. Impaling or wedging is not entirely confined to Lanius; it is regularly recorded in the gray-headed bush-shrike and may occur in other Malaconotus; it has occasionally been recorded in Laniarius, but so far only in captivity.

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