[2] It can easily be distinguished from other brood parasitic cuckoo species by its very thick bill, which is shaped in a rather hawk-like fashion.

[3] The thick-billed cuckoo is found in humid to subhumid woodlands and gallery forests from Guinea in the northwest to Mozambique in the southeast, though it is absent from large areas of the Congo Basin.

[5] In its southernmost regions the thick-billed cuckoo is partially migratory, spending the southern dry season in East Africa.

[6] It is a typical cuckoo in terms of behaviour, feeding on hairy caterpillars, but also having a strong preference for grasshoppers and praying mantises.

This species’ parasitism of the helmetshrikes may complement the similarly sized black cuckoo which exclusively parasitises bush shrikes.