The Slate-colored Boubou (Laniarius funebris) is a species of bird in the family Malaconotidae. It is found in East Africa. Its natural habitats are subtropical or tropical dry forests, dry savanna, subtropical or tropical dry shrubland, and subtropical or tropical moist shrubland.
German naturalist Gustav Hartlaub described the slate-colored boubou in 1863. The adult slate-colored boubou is 8 in long and wholly dark slate grey. The male and female are very similar.
The male's call repertoire includes a noisy shhhhh, or strong clicking and coco-weet, with a rising inflexion on the last syllable.
A 1983 study observed four types of songs sung by males in duets. Researchers concluded that one song type was for mating, two were used to indicate territory, and the final type may have been used to prevent the male Boubou's mate from singing alone, which could attract other males. The frequencies with which the male Boubou sang the territorial songs vary with the extent of threats from other Boubous and with the level of cooperation between mates. A 1992 study of its calls found that a male's likelihood of singing a mating song was correlated with his mate's estradiol levels, rather than his own testosterone levels, suggesting that behavioral cues between a mating pair, rather than hormone levels, are most important in triggering mating songs.